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ckpts/universal/global_step80/zero/16.mlp.dense_4h_to_h.weight/exp_avg_sq.pt

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ckpts/universal/global_step80/zero/8.mlp.dense_4h_to_h.weight/exp_avg.pt

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ckpts/universal/global_step80/zero/8.mlp.dense_4h_to_h.weight/exp_avg_sq.pt

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ckpts/universal/global_step80/zero/8.mlp.dense_4h_to_h.weight/fp32.pt

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venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/api_aggregate.h

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+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Eager evaluation convenience APIs for invoking common functions, including
+// necessary memory allocations
+
+#pragma once
+
+#include <vector>
+
+#include "arrow/compute/function_options.h"
+#include "arrow/datum.h"
+#include "arrow/result.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+
+class Array;
+
+namespace compute {
+
+class ExecContext;
+
+// ----------------------------------------------------------------------
+// Aggregate functions
+
+/// \addtogroup compute-concrete-options
+/// @{
+
+/// \brief Control general scalar aggregate kernel behavior
+///
+/// By default, null values are ignored (skip_nulls = true).
+class ARROW_EXPORT ScalarAggregateOptions : public FunctionOptions {
+ public:
+  explicit ScalarAggregateOptions(bool skip_nulls = true, uint32_t min_count = 1);
+  static constexpr char const kTypeName[] = "ScalarAggregateOptions";
+  static ScalarAggregateOptions Defaults() { return ScalarAggregateOptions{}; }
+
+  /// If true (the default), null values are ignored. Otherwise, if any value is null,
+  /// emit null.
+  bool skip_nulls;
+  /// If less than this many non-null values are observed, emit null.
+  uint32_t min_count;
+};
+
+/// \brief Control count aggregate kernel behavior.
+///
+/// By default, only non-null values are counted.
+class ARROW_EXPORT CountOptions : public FunctionOptions {
+ public:
+  enum CountMode {
+    /// Count only non-null values.
+    ONLY_VALID = 0,
+    /// Count only null values.
+    ONLY_NULL,
+    /// Count both non-null and null values.
+    ALL,
+  };
+  explicit CountOptions(CountMode mode = CountMode::ONLY_VALID);
+  static constexpr char const kTypeName[] = "CountOptions";
+  static CountOptions Defaults() { return CountOptions{}; }
+
+  CountMode mode;
+};
+
+/// \brief Control Mode kernel behavior
+///
+/// Returns top-n common values and counts.
+/// By default, returns the most common value and count.
+class ARROW_EXPORT ModeOptions : public FunctionOptions {
+ public:
+  explicit ModeOptions(int64_t n = 1, bool skip_nulls = true, uint32_t min_count = 0);
+  static constexpr char const kTypeName[] = "ModeOptions";
+  static ModeOptions Defaults() { return ModeOptions{}; }
+
+  int64_t n = 1;
+  /// If true (the default), null values are ignored. Otherwise, if any value is null,
+  /// emit null.
+  bool skip_nulls;
+  /// If less than this many non-null values are observed, emit null.
+  uint32_t min_count;
+};
+
+/// \brief Control Delta Degrees of Freedom (ddof) of Variance and Stddev kernel
+///
+/// The divisor used in calculations is N - ddof, where N is the number of elements.
+/// By default, ddof is zero, and population variance or stddev is returned.
+class ARROW_EXPORT VarianceOptions : public FunctionOptions {
+ public:
+  explicit VarianceOptions(int ddof = 0, bool skip_nulls = true, uint32_t min_count = 0);
+  static constexpr char const kTypeName[] = "VarianceOptions";
+  static VarianceOptions Defaults() { return VarianceOptions{}; }
+
+  int ddof = 0;
+  /// If true (the default), null values are ignored. Otherwise, if any value is null,
+  /// emit null.
+  bool skip_nulls;
+  /// If less than this many non-null values are observed, emit null.
+  uint32_t min_count;
+};
+
+/// \brief Control Quantile kernel behavior
+///
+/// By default, returns the median value.
+class ARROW_EXPORT QuantileOptions : public FunctionOptions {
+ public:
+  /// Interpolation method to use when quantile lies between two data points
+  enum Interpolation {
+    LINEAR = 0,
+    LOWER,
+    HIGHER,
+    NEAREST,
+    MIDPOINT,
+  };
+
+  explicit QuantileOptions(double q = 0.5, enum Interpolation interpolation = LINEAR,
+                           bool skip_nulls = true, uint32_t min_count = 0);
+
+  explicit QuantileOptions(std::vector<double> q,
+                           enum Interpolation interpolation = LINEAR,
+                           bool skip_nulls = true, uint32_t min_count = 0);
+
+  static constexpr char const kTypeName[] = "QuantileOptions";
+  static QuantileOptions Defaults() { return QuantileOptions{}; }
+
+  /// probability level of quantile must be between 0 and 1 inclusive
+  std::vector<double> q;
+  enum Interpolation interpolation;
+  /// If true (the default), null values are ignored. Otherwise, if any value is null,
+  /// emit null.
+  bool skip_nulls;
+  /// If less than this many non-null values are observed, emit null.
+  uint32_t min_count;
+};
+
+/// \brief Control TDigest approximate quantile kernel behavior
+///
+/// By default, returns the median value.
+class ARROW_EXPORT TDigestOptions : public FunctionOptions {
+ public:
+  explicit TDigestOptions(double q = 0.5, uint32_t delta = 100,
+                          uint32_t buffer_size = 500, bool skip_nulls = true,
+                          uint32_t min_count = 0);
+  explicit TDigestOptions(std::vector<double> q, uint32_t delta = 100,
+                          uint32_t buffer_size = 500, bool skip_nulls = true,
+                          uint32_t min_count = 0);
+  static constexpr char const kTypeName[] = "TDigestOptions";
+  static TDigestOptions Defaults() { return TDigestOptions{}; }
+
+  /// probability level of quantile must be between 0 and 1 inclusive
+  std::vector<double> q;
+  /// compression parameter, default 100
+  uint32_t delta;
+  /// input buffer size, default 500
+  uint32_t buffer_size;
+  /// If true (the default), null values are ignored. Otherwise, if any value is null,
+  /// emit null.
+  bool skip_nulls;
+  /// If less than this many non-null values are observed, emit null.
+  uint32_t min_count;
+};
+
+/// \brief Control Index kernel behavior
+class ARROW_EXPORT IndexOptions : public FunctionOptions {
+ public:
+  explicit IndexOptions(std::shared_ptr<Scalar> value);
+  // Default constructor for serialization
+  IndexOptions();
+  static constexpr char const kTypeName[] = "IndexOptions";
+
+  std::shared_ptr<Scalar> value;
+};
+
+/// \brief Configure a grouped aggregation
+struct ARROW_EXPORT Aggregate {
+  Aggregate() = default;
+
+  Aggregate(std::string function, std::shared_ptr<FunctionOptions> options,
+            std::vector<FieldRef> target, std::string name = "")
+      : function(std::move(function)),
+        options(std::move(options)),
+        target(std::move(target)),
+        name(std::move(name)) {}
+
+  Aggregate(std::string function, std::shared_ptr<FunctionOptions> options,
+            FieldRef target, std::string name = "")
+      : Aggregate(std::move(function), std::move(options),
+                  std::vector<FieldRef>{std::move(target)}, std::move(name)) {}
+
+  Aggregate(std::string function, FieldRef target, std::string name)
+      : Aggregate(std::move(function), /*options=*/NULLPTR,
+                  std::vector<FieldRef>{std::move(target)}, std::move(name)) {}
+
+  Aggregate(std::string function, std::string name)
+      : Aggregate(std::move(function), /*options=*/NULLPTR,
+                  /*target=*/std::vector<FieldRef>{}, std::move(name)) {}
+
+  /// the name of the aggregation function
+  std::string function;
+
+  /// options for the aggregation function
+  std::shared_ptr<FunctionOptions> options;
+
+  /// zero or more fields to which aggregations will be applied
+  std::vector<FieldRef> target;
+
+  /// optional output field name for aggregations
+  std::string name;
+};
+
+/// @}
+
+/// \brief Count values in an array.
+///
+/// \param[in] options counting options, see CountOptions for more information
+/// \param[in] datum to count
+/// \param[in] ctx the function execution context, optional
+/// \return out resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Count(const Datum& datum,
+                    const CountOptions& options = CountOptions::Defaults(),
+                    ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the mean of a numeric array.
+///
+/// \param[in] value datum to compute the mean, expecting Array
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed mean as a DoubleScalar
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Mean(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the product of values of a numeric array.
+///
+/// \param[in] value datum to compute product of, expecting Array or ChunkedArray
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed sum as a Scalar
+///
+/// \since 6.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Product(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Sum values of a numeric array.
+///
+/// \param[in] value datum to sum, expecting Array or ChunkedArray
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed sum as a Scalar
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Sum(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the first value of an array
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed first as Scalar
+///
+/// \since 13.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> First(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the last value of an array
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed last as a Scalar
+///
+/// \since 13.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Last(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the min / max of a numeric array
+///
+/// This function returns both the min and max as a struct scalar, with type
+/// struct<min: T, max: T>, where T is the input type
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as a struct<min: T, max: T> scalar
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> MinMax(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Test whether any element in a boolean array evaluates to true.
+///
+/// This function returns true if any of the elements in the array evaluates
+/// to true and false otherwise. Null values are ignored by default.
+/// If null values are taken into account by setting ScalarAggregateOptions
+/// parameter skip_nulls = false then Kleene logic is used.
+/// See KleeneOr for more details on Kleene logic.
+///
+/// \param[in] value input datum, expecting a boolean array
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as a BooleanScalar
+///
+/// \since 3.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Any(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Test whether all elements in a boolean array evaluate to true.
+///
+/// This function returns true if all of the elements in the array evaluate
+/// to true and false otherwise. Null values are ignored by default.
+/// If null values are taken into account by setting ScalarAggregateOptions
+/// parameter skip_nulls = false then Kleene logic is used.
+/// See KleeneAnd for more details on Kleene logic.
+///
+/// \param[in] value input datum, expecting a boolean array
+/// \param[in] options see ScalarAggregateOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as a BooleanScalar
+
+/// \since 3.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> All(
+    const Datum& value,
+    const ScalarAggregateOptions& options = ScalarAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the modal (most common) value of a numeric array
+///
+/// This function returns top-n most common values and number of times they occur as
+/// an array of `struct<mode: T, count: int64>`, where T is the input type.
+/// Values with larger counts are returned before smaller ones.
+/// If there are more than one values with same count, smaller value is returned first.
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see ModeOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as an array of struct<mode: T, count: int64>
+///
+/// \since 2.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Mode(const Datum& value,
+                   const ModeOptions& options = ModeOptions::Defaults(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the standard deviation of a numeric array
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see VarianceOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed standard deviation as a DoubleScalar
+///
+/// \since 2.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Stddev(const Datum& value,
+                     const VarianceOptions& options = VarianceOptions::Defaults(),
+                     ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the variance of a numeric array
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see VarianceOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return datum of the computed variance as a DoubleScalar
+///
+/// \since 2.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Variance(const Datum& value,
+                       const VarianceOptions& options = VarianceOptions::Defaults(),
+                       ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the quantiles of a numeric array
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see QuantileOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as an array
+///
+/// \since 4.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Quantile(const Datum& value,
+                       const QuantileOptions& options = QuantileOptions::Defaults(),
+                       ExecContext* ctx = NULLPTR);
+
+/// \brief Calculate the approximate quantiles of a numeric array with T-Digest algorithm
+///
+/// \param[in] value input datum, expecting Array or ChunkedArray
+/// \param[in] options see TDigestOptions for more information
+/// \param[in] ctx the function execution context, optional
+/// \return resulting datum as an array
+///
+/// \since 4.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> TDigest(const Datum& value,
+                      const TDigestOptions& options = TDigestOptions::Defaults(),
+                      ExecContext* ctx = NULLPTR);
+
+/// \brief Find the first index of a value in an array.
+///
+/// \param[in] value The array to search.
+/// \param[in] options The array to search for. See IndexOptions.
+/// \param[in] ctx the function execution context, optional
+/// \return out a Scalar containing the index (or -1 if not found).
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Index(const Datum& value, const IndexOptions& options,
+                    ExecContext* ctx = NULLPTR);
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/api_scalar.h

@@ -0,0 +1,1717 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Eager evaluation convenience APIs for invoking common functions, including
+// necessary memory allocations
+
+#pragma once
+
+#include <optional>
+#include <string>
+#include <utility>
+
+#include "arrow/compute/function_options.h"
+#include "arrow/compute/type_fwd.h"
+#include "arrow/datum.h"
+#include "arrow/result.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace compute {
+
+/// \addtogroup compute-concrete-options
+///
+/// @{
+
+class ARROW_EXPORT ArithmeticOptions : public FunctionOptions {
+ public:
+  explicit ArithmeticOptions(bool check_overflow = false);
+  static constexpr char const kTypeName[] = "ArithmeticOptions";
+  bool check_overflow;
+};
+
+class ARROW_EXPORT ElementWiseAggregateOptions : public FunctionOptions {
+ public:
+  explicit ElementWiseAggregateOptions(bool skip_nulls = true);
+  static constexpr char const kTypeName[] = "ElementWiseAggregateOptions";
+  static ElementWiseAggregateOptions Defaults() { return ElementWiseAggregateOptions{}; }
+  bool skip_nulls;
+};
+
+/// Rounding and tie-breaking modes for round compute functions.
+/// Additional details and examples are provided in compute.rst.
+enum class RoundMode : int8_t {
+  /// Round to nearest integer less than or equal in magnitude (aka "floor")
+  DOWN,
+  /// Round to nearest integer greater than or equal in magnitude (aka "ceil")
+  UP,
+  /// Get the integral part without fractional digits (aka "trunc")
+  TOWARDS_ZERO,
+  /// Round negative values with DOWN rule
+  /// and positive values with UP rule (aka "away from zero")
+  TOWARDS_INFINITY,
+  /// Round ties with DOWN rule (also called "round half towards negative infinity")
+  HALF_DOWN,
+  /// Round ties with UP rule (also called "round half towards positive infinity")
+  HALF_UP,
+  /// Round ties with TOWARDS_ZERO rule (also called "round half away from infinity")
+  HALF_TOWARDS_ZERO,
+  /// Round ties with TOWARDS_INFINITY rule (also called "round half away from zero")
+  HALF_TOWARDS_INFINITY,
+  /// Round ties to nearest even integer
+  HALF_TO_EVEN,
+  /// Round ties to nearest odd integer
+  HALF_TO_ODD,
+};
+
+class ARROW_EXPORT RoundOptions : public FunctionOptions {
+ public:
+  explicit RoundOptions(int64_t ndigits = 0,
+                        RoundMode round_mode = RoundMode::HALF_TO_EVEN);
+  static constexpr char const kTypeName[] = "RoundOptions";
+  static RoundOptions Defaults() { return RoundOptions(); }
+  /// Rounding precision (number of digits to round to)
+  int64_t ndigits;
+  /// Rounding and tie-breaking mode
+  RoundMode round_mode;
+};
+
+class ARROW_EXPORT RoundBinaryOptions : public FunctionOptions {
+ public:
+  explicit RoundBinaryOptions(RoundMode round_mode = RoundMode::HALF_TO_EVEN);
+  static constexpr char const kTypeName[] = "RoundBinaryOptions";
+  static RoundBinaryOptions Defaults() { return RoundBinaryOptions(); }
+  /// Rounding and tie-breaking mode
+  RoundMode round_mode;
+};
+
+enum class CalendarUnit : int8_t {
+  NANOSECOND,
+  MICROSECOND,
+  MILLISECOND,
+  SECOND,
+  MINUTE,
+  HOUR,
+  DAY,
+  WEEK,
+  MONTH,
+  QUARTER,
+  YEAR
+};
+
+class ARROW_EXPORT RoundTemporalOptions : public FunctionOptions {
+ public:
+  explicit RoundTemporalOptions(int multiple = 1, CalendarUnit unit = CalendarUnit::DAY,
+                                bool week_starts_monday = true,
+                                bool ceil_is_strictly_greater = false,
+                                bool calendar_based_origin = false);
+  static constexpr char const kTypeName[] = "RoundTemporalOptions";
+  static RoundTemporalOptions Defaults() { return RoundTemporalOptions(); }
+
+  /// Number of units to round to
+  int multiple;
+  /// The unit used for rounding of time
+  CalendarUnit unit;
+  /// What day does the week start with (Monday=true, Sunday=false)
+  bool week_starts_monday;
+  /// Enable this flag to return a rounded value that is strictly greater than the input.
+  /// For example: ceiling 1970-01-01T00:00:00 to 3 hours would yield 1970-01-01T03:00:00
+  /// if set to true and 1970-01-01T00:00:00 if set to false.
+  /// This applies for ceiling only.
+  bool ceil_is_strictly_greater;
+  /// By default time is rounded to a multiple of units since 1970-01-01T00:00:00.
+  /// By setting calendar_based_origin to true, time will be rounded to a number
+  /// of units since the last greater calendar unit.
+  /// For example: rounding to a multiple of days since the beginning of the month or
+  /// to hours since the beginning of the day.
+  /// Exceptions: week and quarter are not used as greater units, therefore days will
+  /// will be rounded to the beginning of the month not week. Greater unit of week
+  /// is year.
+  /// Note that ceiling and rounding might change sorting order of an array near greater
+  /// unit change. For example rounding YYYY-mm-dd 23:00:00 to 5 hours will ceil and
+  /// round to YYYY-mm-dd+1 01:00:00 and floor to YYYY-mm-dd 20:00:00. On the other hand
+  /// YYYY-mm-dd+1 00:00:00 will ceil, round and floor to YYYY-mm-dd+1 00:00:00. This
+  /// can break the order of an already ordered array.
+  bool calendar_based_origin;
+};
+
+class ARROW_EXPORT RoundToMultipleOptions : public FunctionOptions {
+ public:
+  explicit RoundToMultipleOptions(double multiple = 1.0,
+                                  RoundMode round_mode = RoundMode::HALF_TO_EVEN);
+  explicit RoundToMultipleOptions(std::shared_ptr<Scalar> multiple,
+                                  RoundMode round_mode = RoundMode::HALF_TO_EVEN);
+  static constexpr char const kTypeName[] = "RoundToMultipleOptions";
+  static RoundToMultipleOptions Defaults() { return RoundToMultipleOptions(); }
+  /// Rounding scale (multiple to round to).
+  ///
+  /// Should be a positive numeric scalar of a type compatible with the
+  /// argument to be rounded. The cast kernel is used to convert the rounding
+  /// multiple to match the result type.
+  std::shared_ptr<Scalar> multiple;
+  /// Rounding and tie-breaking mode
+  RoundMode round_mode;
+};
+
+/// Options for var_args_join.
+class ARROW_EXPORT JoinOptions : public FunctionOptions {
+ public:
+  /// How to handle null values. (A null separator always results in a null output.)
+  enum NullHandlingBehavior {
+    /// A null in any input results in a null in the output.
+    EMIT_NULL,
+    /// Nulls in inputs are skipped.
+    SKIP,
+    /// Nulls in inputs are replaced with the replacement string.
+    REPLACE,
+  };
+  explicit JoinOptions(NullHandlingBehavior null_handling = EMIT_NULL,
+                       std::string null_replacement = "");
+  static constexpr char const kTypeName[] = "JoinOptions";
+  static JoinOptions Defaults() { return JoinOptions(); }
+  NullHandlingBehavior null_handling;
+  std::string null_replacement;
+};
+
+class ARROW_EXPORT MatchSubstringOptions : public FunctionOptions {
+ public:
+  explicit MatchSubstringOptions(std::string pattern, bool ignore_case = false);
+  MatchSubstringOptions();
+  static constexpr char const kTypeName[] = "MatchSubstringOptions";
+
+  /// The exact substring (or regex, depending on kernel) to look for inside input values.
+  std::string pattern;
+  /// Whether to perform a case-insensitive match.
+  bool ignore_case;
+};
+
+class ARROW_EXPORT SplitOptions : public FunctionOptions {
+ public:
+  explicit SplitOptions(int64_t max_splits = -1, bool reverse = false);
+  static constexpr char const kTypeName[] = "SplitOptions";
+
+  /// Maximum number of splits allowed, or unlimited when -1
+  int64_t max_splits;
+  /// Start splitting from the end of the string (only relevant when max_splits != -1)
+  bool reverse;
+};
+
+class ARROW_EXPORT SplitPatternOptions : public FunctionOptions {
+ public:
+  explicit SplitPatternOptions(std::string pattern, int64_t max_splits = -1,
+                               bool reverse = false);
+  SplitPatternOptions();
+  static constexpr char const kTypeName[] = "SplitPatternOptions";
+
+  /// The exact substring to split on.
+  std::string pattern;
+  /// Maximum number of splits allowed, or unlimited when -1
+  int64_t max_splits;
+  /// Start splitting from the end of the string (only relevant when max_splits != -1)
+  bool reverse;
+};
+
+class ARROW_EXPORT ReplaceSliceOptions : public FunctionOptions {
+ public:
+  explicit ReplaceSliceOptions(int64_t start, int64_t stop, std::string replacement);
+  ReplaceSliceOptions();
+  static constexpr char const kTypeName[] = "ReplaceSliceOptions";
+
+  /// Index to start slicing at
+  int64_t start;
+  /// Index to stop slicing at
+  int64_t stop;
+  /// String to replace the slice with
+  std::string replacement;
+};
+
+class ARROW_EXPORT ReplaceSubstringOptions : public FunctionOptions {
+ public:
+  explicit ReplaceSubstringOptions(std::string pattern, std::string replacement,
+                                   int64_t max_replacements = -1);
+  ReplaceSubstringOptions();
+  static constexpr char const kTypeName[] = "ReplaceSubstringOptions";
+
+  /// Pattern to match, literal, or regular expression depending on which kernel is used
+  std::string pattern;
+  /// String to replace the pattern with
+  std::string replacement;
+  /// Max number of substrings to replace (-1 means unbounded)
+  int64_t max_replacements;
+};
+
+class ARROW_EXPORT ExtractRegexOptions : public FunctionOptions {
+ public:
+  explicit ExtractRegexOptions(std::string pattern);
+  ExtractRegexOptions();
+  static constexpr char const kTypeName[] = "ExtractRegexOptions";
+
+  /// Regular expression with named capture fields
+  std::string pattern;
+};
+
+/// Options for IsIn and IndexIn functions
+class ARROW_EXPORT SetLookupOptions : public FunctionOptions {
+ public:
+  /// How to handle null values.
+  enum NullMatchingBehavior {
+    /// MATCH, any null in `value_set` is successfully matched in
+    /// the input.
+    MATCH,
+    /// SKIP, any null in `value_set` is ignored and nulls in the input
+    /// produce null (IndexIn) or false (IsIn) values in the output.
+    SKIP,
+    /// EMIT_NULL, any null in `value_set` is ignored and nulls in the
+    /// input produce null (IndexIn and IsIn) values in the output.
+    EMIT_NULL,
+    /// INCONCLUSIVE, null values are regarded as unknown values, which is
+    /// sql-compatible. nulls in the input produce null (IndexIn and IsIn)
+    /// values in the output. Besides, if `value_set` contains a null,
+    /// non-null unmatched values in the input also produce null values
+    /// (IndexIn and IsIn) in the output.
+    INCONCLUSIVE
+  };
+
+  explicit SetLookupOptions(Datum value_set, NullMatchingBehavior = MATCH);
+  SetLookupOptions();
+
+  // DEPRECATED(will be removed after removing of skip_nulls)
+  explicit SetLookupOptions(Datum value_set, bool skip_nulls);
+
+  static constexpr char const kTypeName[] = "SetLookupOptions";
+
+  /// The set of values to look up input values into.
+  Datum value_set;
+
+  NullMatchingBehavior null_matching_behavior;
+
+  // DEPRECATED(will be removed after removing of skip_nulls)
+  NullMatchingBehavior GetNullMatchingBehavior() const;
+
+  // DEPRECATED(use null_matching_behavior instead)
+  /// Whether nulls in `value_set` count for lookup.
+  ///
+  /// If true, any null in `value_set` is ignored and nulls in the input
+  /// produce null (IndexIn) or false (IsIn) values in the output.
+  /// If false, any null in `value_set` is successfully matched in
+  /// the input.
+  std::optional<bool> skip_nulls;
+};
+
+/// Options for struct_field function
+class ARROW_EXPORT StructFieldOptions : public FunctionOptions {
+ public:
+  explicit StructFieldOptions(std::vector<int> indices);
+  explicit StructFieldOptions(std::initializer_list<int>);
+  explicit StructFieldOptions(FieldRef field_ref);
+  StructFieldOptions();
+  static constexpr char const kTypeName[] = "StructFieldOptions";
+
+  /// The FieldRef specifying what to extract from struct or union.
+  FieldRef field_ref;
+};
+
+class ARROW_EXPORT StrptimeOptions : public FunctionOptions {
+ public:
+  explicit StrptimeOptions(std::string format, TimeUnit::type unit,
+                           bool error_is_null = false);
+  StrptimeOptions();
+  static constexpr char const kTypeName[] = "StrptimeOptions";
+
+  /// The desired format string.
+  std::string format;
+  /// The desired time resolution
+  TimeUnit::type unit;
+  /// Return null on parsing errors if true or raise if false
+  bool error_is_null;
+};
+
+class ARROW_EXPORT StrftimeOptions : public FunctionOptions {
+ public:
+  explicit StrftimeOptions(std::string format, std::string locale = "C");
+  StrftimeOptions();
+
+  static constexpr char const kTypeName[] = "StrftimeOptions";
+
+  static constexpr const char* kDefaultFormat = "%Y-%m-%dT%H:%M:%S";
+
+  /// The desired format string.
+  std::string format;
+  /// The desired output locale string.
+  std::string locale;
+};
+
+class ARROW_EXPORT PadOptions : public FunctionOptions {
+ public:
+  explicit PadOptions(int64_t width, std::string padding = " ");
+  PadOptions();
+  static constexpr char const kTypeName[] = "PadOptions";
+
+  /// The desired string length.
+  int64_t width;
+  /// What to pad the string with. Should be one codepoint (Unicode)/byte (ASCII).
+  std::string padding;
+};
+
+class ARROW_EXPORT TrimOptions : public FunctionOptions {
+ public:
+  explicit TrimOptions(std::string characters);
+  TrimOptions();
+  static constexpr char const kTypeName[] = "TrimOptions";
+
+  /// The individual characters to be trimmed from the string.
+  std::string characters;
+};
+
+class ARROW_EXPORT SliceOptions : public FunctionOptions {
+ public:
+  explicit SliceOptions(int64_t start, int64_t stop = std::numeric_limits<int64_t>::max(),
+                        int64_t step = 1);
+  SliceOptions();
+  static constexpr char const kTypeName[] = "SliceOptions";
+  int64_t start, stop, step;
+};
+
+class ARROW_EXPORT ListSliceOptions : public FunctionOptions {
+ public:
+  explicit ListSliceOptions(int64_t start, std::optional<int64_t> stop = std::nullopt,
+                            int64_t step = 1,
+                            std::optional<bool> return_fixed_size_list = std::nullopt);
+  ListSliceOptions();
+  static constexpr char const kTypeName[] = "ListSliceOptions";
+  /// The start of list slicing.
+  int64_t start;
+  /// Optional stop of list slicing. If not set, then slice to end. (NotImplemented)
+  std::optional<int64_t> stop;
+  /// Slicing step
+  int64_t step;
+  // Whether to return a FixedSizeListArray. If true _and_ stop is after
+  // a list element's length, nulls will be appended to create the requested slice size.
+  // Default of `nullopt` will return whatever type it got in.
+  std::optional<bool> return_fixed_size_list;
+};
+
+class ARROW_EXPORT NullOptions : public FunctionOptions {
+ public:
+  explicit NullOptions(bool nan_is_null = false);
+  static constexpr char const kTypeName[] = "NullOptions";
+  static NullOptions Defaults() { return NullOptions{}; }
+
+  bool nan_is_null;
+};
+
+enum CompareOperator : int8_t {
+  EQUAL,
+  NOT_EQUAL,
+  GREATER,
+  GREATER_EQUAL,
+  LESS,
+  LESS_EQUAL,
+};
+
+struct ARROW_EXPORT CompareOptions {
+  explicit CompareOptions(CompareOperator op) : op(op) {}
+  CompareOptions() : CompareOptions(CompareOperator::EQUAL) {}
+  enum CompareOperator op;
+};
+
+class ARROW_EXPORT MakeStructOptions : public FunctionOptions {
+ public:
+  MakeStructOptions(std::vector<std::string> n, std::vector<bool> r,
+                    std::vector<std::shared_ptr<const KeyValueMetadata>> m);
+  explicit MakeStructOptions(std::vector<std::string> n);
+  MakeStructOptions();
+  static constexpr char const kTypeName[] = "MakeStructOptions";
+
+  /// Names for wrapped columns
+  std::vector<std::string> field_names;
+
+  /// Nullability bits for wrapped columns
+  std::vector<bool> field_nullability;
+
+  /// Metadata attached to wrapped columns
+  std::vector<std::shared_ptr<const KeyValueMetadata>> field_metadata;
+};
+
+struct ARROW_EXPORT DayOfWeekOptions : public FunctionOptions {
+ public:
+  explicit DayOfWeekOptions(bool count_from_zero = true, uint32_t week_start = 1);
+  static constexpr char const kTypeName[] = "DayOfWeekOptions";
+  static DayOfWeekOptions Defaults() { return DayOfWeekOptions(); }
+
+  /// Number days from 0 if true and from 1 if false
+  bool count_from_zero;
+  /// What day does the week start with (Monday=1, Sunday=7).
+  /// The numbering is unaffected by the count_from_zero parameter.
+  uint32_t week_start;
+};
+
+/// Used to control timestamp timezone conversion and handling ambiguous/nonexistent
+/// times.
+struct ARROW_EXPORT AssumeTimezoneOptions : public FunctionOptions {
+ public:
+  /// \brief How to interpret ambiguous local times that can be interpreted as
+  /// multiple instants (normally two) due to DST shifts.
+  ///
+  /// AMBIGUOUS_EARLIEST emits the earliest instant amongst possible interpretations.
+  /// AMBIGUOUS_LATEST emits the latest instant amongst possible interpretations.
+  enum Ambiguous { AMBIGUOUS_RAISE, AMBIGUOUS_EARLIEST, AMBIGUOUS_LATEST };
+
+  /// \brief How to handle local times that do not exist due to DST shifts.
+  ///
+  /// NONEXISTENT_EARLIEST emits the instant "just before" the DST shift instant
+  /// in the given timestamp precision (for example, for a nanoseconds precision
+  /// timestamp, this is one nanosecond before the DST shift instant).
+  /// NONEXISTENT_LATEST emits the DST shift instant.
+  enum Nonexistent { NONEXISTENT_RAISE, NONEXISTENT_EARLIEST, NONEXISTENT_LATEST };
+
+  explicit AssumeTimezoneOptions(std::string timezone,
+                                 Ambiguous ambiguous = AMBIGUOUS_RAISE,
+                                 Nonexistent nonexistent = NONEXISTENT_RAISE);
+  AssumeTimezoneOptions();
+  static constexpr char const kTypeName[] = "AssumeTimezoneOptions";
+
+  /// Timezone to convert timestamps from
+  std::string timezone;
+
+  /// How to interpret ambiguous local times (due to DST shifts)
+  Ambiguous ambiguous;
+  /// How to interpret nonexistent local times (due to DST shifts)
+  Nonexistent nonexistent;
+};
+
+struct ARROW_EXPORT WeekOptions : public FunctionOptions {
+ public:
+  explicit WeekOptions(bool week_starts_monday = true, bool count_from_zero = false,
+                       bool first_week_is_fully_in_year = false);
+  static constexpr char const kTypeName[] = "WeekOptions";
+  static WeekOptions Defaults() { return WeekOptions{}; }
+  static WeekOptions ISODefaults() {
+    return WeekOptions{/*week_starts_monday*/ true,
+                       /*count_from_zero=*/false,
+                       /*first_week_is_fully_in_year=*/false};
+  }
+  static WeekOptions USDefaults() {
+    return WeekOptions{/*week_starts_monday*/ false,
+                       /*count_from_zero=*/false,
+                       /*first_week_is_fully_in_year=*/false};
+  }
+
+  /// What day does the week start with (Monday=true, Sunday=false)
+  bool week_starts_monday;
+  /// Dates from current year that fall into last ISO week of the previous year return
+  /// 0 if true and 52 or 53 if false.
+  bool count_from_zero;
+  /// Must the first week be fully in January (true), or is a week that begins on
+  /// December 29, 30, or 31 considered to be the first week of the new year (false)?
+  bool first_week_is_fully_in_year;
+};
+
+struct ARROW_EXPORT Utf8NormalizeOptions : public FunctionOptions {
+ public:
+  enum Form { NFC, NFKC, NFD, NFKD };
+
+  explicit Utf8NormalizeOptions(Form form = NFC);
+  static Utf8NormalizeOptions Defaults() { return Utf8NormalizeOptions(); }
+  static constexpr char const kTypeName[] = "Utf8NormalizeOptions";
+
+  /// The Unicode normalization form to apply
+  Form form;
+};
+
+class ARROW_EXPORT RandomOptions : public FunctionOptions {
+ public:
+  enum Initializer { SystemRandom, Seed };
+
+  static RandomOptions FromSystemRandom() { return RandomOptions{SystemRandom, 0}; }
+  static RandomOptions FromSeed(uint64_t seed) { return RandomOptions{Seed, seed}; }
+
+  RandomOptions(Initializer initializer, uint64_t seed);
+  RandomOptions();
+  static constexpr char const kTypeName[] = "RandomOptions";
+  static RandomOptions Defaults() { return RandomOptions(); }
+
+  /// The type of initialization for random number generation - system or provided seed.
+  Initializer initializer;
+  /// The seed value used to initialize the random number generation.
+  uint64_t seed;
+};
+
+/// Options for map_lookup function
+class ARROW_EXPORT MapLookupOptions : public FunctionOptions {
+ public:
+  enum Occurrence {
+    /// Return the first matching value
+    FIRST,
+    /// Return the last matching value
+    LAST,
+    /// Return all matching values
+    ALL
+  };
+
+  explicit MapLookupOptions(std::shared_ptr<Scalar> query_key, Occurrence occurrence);
+  MapLookupOptions();
+
+  constexpr static char const kTypeName[] = "MapLookupOptions";
+
+  /// The key to lookup in the map
+  std::shared_ptr<Scalar> query_key;
+
+  /// Whether to return the first, last, or all matching values
+  Occurrence occurrence;
+};
+
+/// @}
+
+/// \brief Get the absolute value of a value.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value transformed
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise absolute value
+ARROW_EXPORT
+Result<Datum> AbsoluteValue(const Datum& arg,
+                            ArithmeticOptions options = ArithmeticOptions(),
+                            ExecContext* ctx = NULLPTR);
+
+/// \brief Add two values together. Array values must be the same length. If
+/// either addend is null the result will be null.
+///
+/// \param[in] left the first addend
+/// \param[in] right the second addend
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise sum
+ARROW_EXPORT
+Result<Datum> Add(const Datum& left, const Datum& right,
+                  ArithmeticOptions options = ArithmeticOptions(),
+                  ExecContext* ctx = NULLPTR);
+
+/// \brief Subtract two values. Array values must be the same length. If the
+/// minuend or subtrahend is null the result will be null.
+///
+/// \param[in] left the value subtracted from (minuend)
+/// \param[in] right the value by which the minuend is reduced (subtrahend)
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise difference
+ARROW_EXPORT
+Result<Datum> Subtract(const Datum& left, const Datum& right,
+                       ArithmeticOptions options = ArithmeticOptions(),
+                       ExecContext* ctx = NULLPTR);
+
+/// \brief Multiply two values. Array values must be the same length. If either
+/// factor is null the result will be null.
+///
+/// \param[in] left the first factor
+/// \param[in] right the second factor
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise product
+ARROW_EXPORT
+Result<Datum> Multiply(const Datum& left, const Datum& right,
+                       ArithmeticOptions options = ArithmeticOptions(),
+                       ExecContext* ctx = NULLPTR);
+
+/// \brief Divide two values. Array values must be the same length. If either
+/// argument is null the result will be null. For integer types, if there is
+/// a zero divisor, an error will be raised.
+///
+/// \param[in] left the dividend
+/// \param[in] right the divisor
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise quotient
+ARROW_EXPORT
+Result<Datum> Divide(const Datum& left, const Datum& right,
+                     ArithmeticOptions options = ArithmeticOptions(),
+                     ExecContext* ctx = NULLPTR);
+
+/// \brief Negate values.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value negated
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise negation
+ARROW_EXPORT
+Result<Datum> Negate(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                     ExecContext* ctx = NULLPTR);
+
+/// \brief Raise the values of base array to the power of the exponent array values.
+/// Array values must be the same length. If either base or exponent is null the result
+/// will be null.
+///
+/// \param[in] left the base
+/// \param[in] right the exponent
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise base value raised to the power of exponent
+ARROW_EXPORT
+Result<Datum> Power(const Datum& left, const Datum& right,
+                    ArithmeticOptions options = ArithmeticOptions(),
+                    ExecContext* ctx = NULLPTR);
+
+/// \brief Raise Euler's number to the power of specified exponent, element-wise.
+/// If the exponent value is null the result will be null.
+///
+/// \param[in] arg the exponent
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise Euler's number raised to the power of exponent
+ARROW_EXPORT
+Result<Datum> Exp(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Left shift the left array by the right array. Array values must be the
+/// same length. If either operand is null, the result will be null.
+///
+/// \param[in] left the value to shift
+/// \param[in] right the value to shift by
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise left value shifted left by the right value
+ARROW_EXPORT
+Result<Datum> ShiftLeft(const Datum& left, const Datum& right,
+                        ArithmeticOptions options = ArithmeticOptions(),
+                        ExecContext* ctx = NULLPTR);
+
+/// \brief Right shift the left array by the right array. Array values must be the
+/// same length. If either operand is null, the result will be null. Performs a
+/// logical shift for unsigned values, and an arithmetic shift for signed values.
+///
+/// \param[in] left the value to shift
+/// \param[in] right the value to shift by
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise left value shifted right by the right value
+ARROW_EXPORT
+Result<Datum> ShiftRight(const Datum& left, const Datum& right,
+                         ArithmeticOptions options = ArithmeticOptions(),
+                         ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the sine of the array values.
+/// \param[in] arg The values to compute the sine for.
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise sine of the values
+ARROW_EXPORT
+Result<Datum> Sin(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                  ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cosine of the array values.
+/// \param[in] arg The values to compute the cosine for.
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise cosine of the values
+ARROW_EXPORT
+Result<Datum> Cos(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                  ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the inverse sine (arcsine) of the array values.
+/// \param[in] arg The values to compute the inverse sine for.
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise inverse sine of the values
+ARROW_EXPORT
+Result<Datum> Asin(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the inverse cosine (arccosine) of the array values.
+/// \param[in] arg The values to compute the inverse cosine for.
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise inverse cosine of the values
+ARROW_EXPORT
+Result<Datum> Acos(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the tangent of the array values.
+/// \param[in] arg The values to compute the tangent for.
+/// \param[in] options arithmetic options (enable/disable overflow checking), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise tangent of the values
+ARROW_EXPORT
+Result<Datum> Tan(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                  ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the inverse tangent (arctangent) of the array values.
+/// \param[in] arg The values to compute the inverse tangent for.
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise inverse tangent of the values
+ARROW_EXPORT
+Result<Datum> Atan(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the inverse tangent (arctangent) of y/x, using the
+/// argument signs to determine the correct quadrant.
+/// \param[in] y The y-values to compute the inverse tangent for.
+/// \param[in] x The x-values to compute the inverse tangent for.
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise inverse tangent of the values
+ARROW_EXPORT
+Result<Datum> Atan2(const Datum& y, const Datum& x, ExecContext* ctx = NULLPTR);
+
+/// \brief Get the natural log of a value.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg The values to compute the logarithm for.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise natural log
+ARROW_EXPORT
+Result<Datum> Ln(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                 ExecContext* ctx = NULLPTR);
+
+/// \brief Get the log base 10 of a value.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg The values to compute the logarithm for.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise log base 10
+ARROW_EXPORT
+Result<Datum> Log10(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                    ExecContext* ctx = NULLPTR);
+
+/// \brief Get the log base 2 of a value.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg The values to compute the logarithm for.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise log base 2
+ARROW_EXPORT
+Result<Datum> Log2(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Get the natural log of (1 + value).
+///
+/// If argument is null the result will be null.
+/// This function may be more accurate than Log(1 + value) for values close to zero.
+///
+/// \param[in] arg The values to compute the logarithm for.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise natural log
+ARROW_EXPORT
+Result<Datum> Log1p(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                    ExecContext* ctx = NULLPTR);
+
+/// \brief Get the log of a value to the given base.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg The values to compute the logarithm for.
+/// \param[in] base The given base.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise log to the given base
+ARROW_EXPORT
+Result<Datum> Logb(const Datum& arg, const Datum& base,
+                   ArithmeticOptions options = ArithmeticOptions(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Get the square-root of a value.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg The values to compute the square-root for.
+/// \param[in] options arithmetic options (overflow handling), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the elementwise square-root
+ARROW_EXPORT
+Result<Datum> Sqrt(const Datum& arg, ArithmeticOptions options = ArithmeticOptions(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Round to the nearest integer less than or equal in magnitude to the
+/// argument.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value to round
+/// \param[in] ctx the function execution context, optional
+/// \return the rounded value
+ARROW_EXPORT
+Result<Datum> Floor(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Round to the nearest integer greater than or equal in magnitude to the
+/// argument.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value to round
+/// \param[in] ctx the function execution context, optional
+/// \return the rounded value
+ARROW_EXPORT
+Result<Datum> Ceil(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Get the integral part without fractional digits.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value to truncate
+/// \param[in] ctx the function execution context, optional
+/// \return the truncated value
+ARROW_EXPORT
+Result<Datum> Trunc(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Find the element-wise maximum of any number of arrays or scalars.
+/// Array values must be the same length.
+///
+/// \param[in] args arrays or scalars to operate on.
+/// \param[in] options options for handling nulls, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise maximum
+ARROW_EXPORT
+Result<Datum> MaxElementWise(
+    const std::vector<Datum>& args,
+    ElementWiseAggregateOptions options = ElementWiseAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Find the element-wise minimum of any number of arrays or scalars.
+/// Array values must be the same length.
+///
+/// \param[in] args arrays or scalars to operate on.
+/// \param[in] options options for handling nulls, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise minimum
+ARROW_EXPORT
+Result<Datum> MinElementWise(
+    const std::vector<Datum>& args,
+    ElementWiseAggregateOptions options = ElementWiseAggregateOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Get the sign of a value. Array values can be of arbitrary length. If argument
+/// is null the result will be null.
+///
+/// \param[in] arg the value to extract sign from
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise sign function
+ARROW_EXPORT
+Result<Datum> Sign(const Datum& arg, ExecContext* ctx = NULLPTR);
+
+/// \brief Round a value to a given precision.
+///
+/// If arg is null the result will be null.
+///
+/// \param[in] arg the value to be rounded
+/// \param[in] options rounding options (rounding mode and number of digits), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+ARROW_EXPORT
+Result<Datum> Round(const Datum& arg, RoundOptions options = RoundOptions::Defaults(),
+                    ExecContext* ctx = NULLPTR);
+
+/// \brief Round a value to a given precision.
+///
+/// If arg1 is null the result will be null.
+/// If arg2 is null then the result will be null. If arg2 is negative, then the rounding
+/// place will be shifted to the left (thus -1 would correspond to rounding to the nearest
+/// ten).  If positive, the rounding place will shift to the right (and +1 would
+/// correspond to rounding to the nearest tenth).
+///
+/// \param[in] arg1 the value to be rounded
+/// \param[in] arg2 the number of significant digits to round to
+/// \param[in] options rounding options, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+ARROW_EXPORT
+Result<Datum> RoundBinary(const Datum& arg1, const Datum& arg2,
+                          RoundBinaryOptions options = RoundBinaryOptions::Defaults(),
+                          ExecContext* ctx = NULLPTR);
+
+/// \brief Round a value to a given multiple.
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the value to round
+/// \param[in] options rounding options (rounding mode and multiple), optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+ARROW_EXPORT
+Result<Datum> RoundToMultiple(
+    const Datum& arg, RoundToMultipleOptions options = RoundToMultipleOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Ceil a temporal value to a given frequency
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the temporal value to ceil
+/// \param[in] options temporal rounding options, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+///
+/// \since 7.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> CeilTemporal(
+    const Datum& arg, RoundTemporalOptions options = RoundTemporalOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Floor a temporal value to a given frequency
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the temporal value to floor
+/// \param[in] options temporal rounding options, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+///
+/// \since 7.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> FloorTemporal(
+    const Datum& arg, RoundTemporalOptions options = RoundTemporalOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Round a temporal value to a given frequency
+///
+/// If argument is null the result will be null.
+///
+/// \param[in] arg the temporal value to round
+/// \param[in] options temporal rounding options, optional
+/// \param[in] ctx the function execution context, optional
+/// \return the element-wise rounded value
+///
+/// \since 7.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> RoundTemporal(
+    const Datum& arg, RoundTemporalOptions options = RoundTemporalOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Invert the values of a boolean datum
+/// \param[in] value datum to invert
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Invert(const Datum& value, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise AND of two boolean datums which always propagates nulls
+/// (null and false is null).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> And(const Datum& left, const Datum& right, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise AND of two boolean datums with a Kleene truth table
+/// (null and false is false).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> KleeneAnd(const Datum& left, const Datum& right,
+                        ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise OR of two boolean datums which always propagates nulls
+/// (null and true is null).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Or(const Datum& left, const Datum& right, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise OR of two boolean datums with a Kleene truth table
+/// (null or true is true).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> KleeneOr(const Datum& left, const Datum& right, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise XOR of two boolean datums
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Xor(const Datum& left, const Datum& right, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise AND NOT of two boolean datums which always propagates nulls
+/// (null and not true is null).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 3.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> AndNot(const Datum& left, const Datum& right, ExecContext* ctx = NULLPTR);
+
+/// \brief Element-wise AND NOT of two boolean datums with a Kleene truth table
+/// (false and not null is false, null and not true is false).
+///
+/// \param[in] left left operand
+/// \param[in] right right operand
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 3.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> KleeneAndNot(const Datum& left, const Datum& right,
+                           ExecContext* ctx = NULLPTR);
+
+/// \brief IsIn returns true for each element of `values` that is contained in
+/// `value_set`
+///
+/// Behaviour of nulls is governed by SetLookupOptions::skip_nulls.
+///
+/// \param[in] values array-like input to look up in value_set
+/// \param[in] options SetLookupOptions
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IsIn(const Datum& values, const SetLookupOptions& options,
+                   ExecContext* ctx = NULLPTR);
+ARROW_EXPORT
+Result<Datum> IsIn(const Datum& values, const Datum& value_set,
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief IndexIn examines each slot in the values against a value_set array.
+/// If the value is not found in value_set, null will be output.
+/// If found, the index of occurrence within value_set (ignoring duplicates)
+/// will be output.
+///
+/// For example given values = [99, 42, 3, null] and
+/// value_set = [3, 3, 99], the output will be = [2, null, 0, null]
+///
+/// Behaviour of nulls is governed by SetLookupOptions::skip_nulls.
+///
+/// \param[in] values array-like input
+/// \param[in] options SetLookupOptions
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IndexIn(const Datum& values, const SetLookupOptions& options,
+                      ExecContext* ctx = NULLPTR);
+ARROW_EXPORT
+Result<Datum> IndexIn(const Datum& values, const Datum& value_set,
+                      ExecContext* ctx = NULLPTR);
+
+/// \brief IsValid returns true for each element of `values` that is not null,
+/// false otherwise
+///
+/// \param[in] values input to examine for validity
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IsValid(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief IsNull returns true for each element of `values` that is null,
+/// false otherwise
+///
+/// \param[in] values input to examine for nullity
+/// \param[in] options NullOptions
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IsNull(const Datum& values, NullOptions options = NullOptions::Defaults(),
+                     ExecContext* ctx = NULLPTR);
+
+/// \brief IsNan returns true for each element of `values` that is NaN,
+/// false otherwise
+///
+/// \param[in] values input to look for NaN
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 3.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IsNan(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief IfElse returns elements chosen from `left` or `right`
+/// depending on `cond`. `null` values in `cond` will be promoted to the result
+///
+/// \param[in] cond `Boolean` condition Scalar/ Array
+/// \param[in] left Scalar/ Array
+/// \param[in] right Scalar/ Array
+/// \param[in] ctx the function execution context, optional
+///
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IfElse(const Datum& cond, const Datum& left, const Datum& right,
+                     ExecContext* ctx = NULLPTR);
+
+/// \brief CaseWhen behaves like a switch/case or if-else if-else statement: for
+/// each row, select the first value for which the corresponding condition is
+/// true, or (if given) select the 'else' value, else emit null. Note that a
+/// null condition is the same as false.
+///
+/// \param[in] cond Conditions (Boolean)
+/// \param[in] cases Values (any type), along with an optional 'else' value.
+/// \param[in] ctx the function execution context, optional
+///
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> CaseWhen(const Datum& cond, const std::vector<Datum>& cases,
+                       ExecContext* ctx = NULLPTR);
+
+/// \brief Year returns year for each element of `values`
+///
+/// \param[in] values input to extract year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Year(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief IsLeapYear returns if a year is a leap year for each element of `values`
+///
+/// \param[in] values input to extract leap year indicator from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> IsLeapYear(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Month returns month for each element of `values`.
+/// Month is encoded as January=1, December=12
+///
+/// \param[in] values input to extract month from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Month(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Day returns day number for each element of `values`
+///
+/// \param[in] values input to extract day from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Day(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief YearMonthDay returns a struct containing the Year, Month and Day value for
+/// each element of `values`.
+///
+/// \param[in] values input to extract (year, month, day) struct from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 7.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> YearMonthDay(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief DayOfWeek returns number of the day of the week value for each element of
+/// `values`.
+///
+/// By default week starts on Monday denoted by 0 and ends on Sunday denoted
+/// by 6. Start day of the week (Monday=1, Sunday=7) and numbering base (0 or 1) can be
+/// set using DayOfWeekOptions
+///
+/// \param[in] values input to extract number of the day of the week from
+/// \param[in] options for setting start of the week and day numbering
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> DayOfWeek(const Datum& values,
+                                     DayOfWeekOptions options = DayOfWeekOptions(),
+                                     ExecContext* ctx = NULLPTR);
+
+/// \brief DayOfYear returns number of day of the year for each element of `values`.
+/// January 1st maps to day number 1, February 1st to 32, etc.
+///
+/// \param[in] values input to extract number of day of the year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> DayOfYear(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief ISOYear returns ISO year number for each element of `values`.
+/// First week of an ISO year has the majority (4 or more) of its days in January.
+///
+/// \param[in] values input to extract ISO year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> ISOYear(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief USYear returns US epidemiological year number for each element of `values`.
+/// First week of US epidemiological year has the majority (4 or more) of it's
+/// days in January. Last week of US epidemiological year has the year's last
+/// Wednesday in it. US epidemiological week starts on Sunday.
+///
+/// \param[in] values input to extract US epidemiological year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> USYear(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief ISOWeek returns ISO week of year number for each element of `values`.
+/// First ISO week has the majority (4 or more) of its days in January.
+/// ISO week starts on Monday. Year can have 52 or 53 weeks.
+/// Week numbering can start with 1.
+///
+/// \param[in] values input to extract ISO week of year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> ISOWeek(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief USWeek returns US week of year number for each element of `values`.
+/// First US week has the majority (4 or more) of its days in January.
+/// US week starts on Sunday. Year can have 52 or 53 weeks.
+/// Week numbering starts with 1.
+///
+/// \param[in] values input to extract US week of year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 6.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> USWeek(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Week returns week of year number for each element of `values`.
+/// First ISO week has the majority (4 or more) of its days in January.
+/// Year can have 52 or 53 weeks. Week numbering can start with 0 or 1
+/// depending on DayOfWeekOptions.count_from_zero.
+///
+/// \param[in] values input to extract week of year from
+/// \param[in] options for setting numbering start
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 6.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> Week(const Datum& values, WeekOptions options = WeekOptions(),
+                                ExecContext* ctx = NULLPTR);
+
+/// \brief ISOCalendar returns a (ISO year, ISO week, ISO day of week) struct for
+/// each element of `values`.
+/// ISO week starts on Monday denoted by 1 and ends on Sunday denoted by 7.
+///
+/// \param[in] values input to ISO calendar struct from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> ISOCalendar(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Quarter returns the quarter of year number for each element of `values`
+/// First quarter maps to 1 and fourth quarter maps to 4.
+///
+/// \param[in] values input to extract quarter of year from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> Quarter(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Hour returns hour value for each element of `values`
+///
+/// \param[in] values input to extract hour from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Hour(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Minute returns minutes value for each element of `values`
+///
+/// \param[in] values input to extract minutes from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Minute(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Second returns seconds value for each element of `values`
+///
+/// \param[in] values input to extract seconds from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Second(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Millisecond returns number of milliseconds since the last full second
+/// for each element of `values`
+///
+/// \param[in] values input to extract milliseconds from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Millisecond(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Microsecond returns number of microseconds since the last full millisecond
+/// for each element of `values`
+///
+/// \param[in] values input to extract microseconds from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Microsecond(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Nanosecond returns number of nanoseconds since the last full millisecond
+/// for each element of `values`
+///
+/// \param[in] values input to extract nanoseconds from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> Nanosecond(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Subsecond returns the fraction of second elapsed since last full second
+/// as a float for each element of `values`
+///
+/// \param[in] values input to extract subsecond from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> Subsecond(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Format timestamps according to a format string
+///
+/// Return formatted time strings according to the format string
+/// `StrftimeOptions::format` and to the locale specifier `Strftime::locale`.
+///
+/// \param[in] values input timestamps
+/// \param[in] options for setting format string and locale
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 6.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> Strftime(const Datum& values, StrftimeOptions options,
+                                    ExecContext* ctx = NULLPTR);
+
+/// \brief Parse timestamps according to a format string
+///
+/// Return parsed timestamps according to the format string
+/// `StrptimeOptions::format` at time resolution `Strftime::unit`. Parse errors are
+/// raised depending on the `Strftime::error_is_null` setting.
+///
+/// \param[in] values input strings
+/// \param[in] options for setting format string, unit and error_is_null
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> Strptime(const Datum& values, StrptimeOptions options,
+                                    ExecContext* ctx = NULLPTR);
+
+/// \brief Converts timestamps from local timestamp without a timezone to a timestamp with
+/// timezone, interpreting the local timestamp as being in the specified timezone for each
+/// element of `values`
+///
+/// \param[in] values input to convert
+/// \param[in] options for setting source timezone, exception and ambiguous timestamp
+/// handling.
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 6.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> AssumeTimezone(const Datum& values,
+                                          AssumeTimezoneOptions options,
+                                          ExecContext* ctx = NULLPTR);
+
+/// \brief IsDaylightSavings extracts if currently observing daylight savings for each
+/// element of `values`
+///
+/// \param[in] values input to extract daylight savings indicator from
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> IsDaylightSavings(const Datum& values,
+                                             ExecContext* ctx = NULLPTR);
+
+/// \brief LocalTimestamp converts timestamp to timezone naive local timestamp
+///
+/// \param[in] values input to convert to local time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 12.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> LocalTimestamp(const Datum& values,
+                                          ExecContext* ctx = NULLPTR);
+
+/// \brief Years Between finds the number of years between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> YearsBetween(const Datum& left, const Datum& right,
+                                        ExecContext* ctx = NULLPTR);
+
+/// \brief Quarters Between finds the number of quarters between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> QuartersBetween(const Datum& left, const Datum& right,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Months Between finds the number of month between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MonthsBetween(const Datum& left, const Datum& right,
+                                         ExecContext* ctx = NULLPTR);
+
+/// \brief Weeks Between finds the number of weeks between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> WeeksBetween(const Datum& left, const Datum& right,
+                                        ExecContext* ctx = NULLPTR);
+
+/// \brief Month Day Nano Between finds the number of months, days, and nanoseconds
+/// between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MonthDayNanoBetween(const Datum& left, const Datum& right,
+                                               ExecContext* ctx = NULLPTR);
+
+/// \brief DayTime Between finds the number of days and milliseconds between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> DayTimeBetween(const Datum& left, const Datum& right,
+                                          ExecContext* ctx = NULLPTR);
+
+/// \brief Days Between finds the number of days between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> DaysBetween(const Datum& left, const Datum& right,
+                                       ExecContext* ctx = NULLPTR);
+
+/// \brief Hours Between finds the number of hours between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> HoursBetween(const Datum& left, const Datum& right,
+                                        ExecContext* ctx = NULLPTR);
+
+/// \brief Minutes Between finds the number of minutes between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MinutesBetween(const Datum& left, const Datum& right,
+                                          ExecContext* ctx = NULLPTR);
+
+/// \brief Seconds Between finds the number of hours between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> SecondsBetween(const Datum& left, const Datum& right,
+                                          ExecContext* ctx = NULLPTR);
+
+/// \brief Milliseconds Between finds the number of milliseconds between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MillisecondsBetween(const Datum& left, const Datum& right,
+                                               ExecContext* ctx = NULLPTR);
+
+/// \brief Microseconds Between finds the number of microseconds between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MicrosecondsBetween(const Datum& left, const Datum& right,
+                                               ExecContext* ctx = NULLPTR);
+
+/// \brief Nanoseconds Between finds the number of nanoseconds between two values
+///
+/// \param[in] left input treated as the start time
+/// \param[in] right input treated as the end time
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> NanosecondsBetween(const Datum& left, const Datum& right,
+                                              ExecContext* ctx = NULLPTR);
+
+/// \brief Finds either the FIRST, LAST, or ALL items with a key that matches the given
+/// query key in a map.
+///
+/// Returns an array of items for FIRST and LAST, and an array of list of items for ALL.
+///
+/// \param[in] map to look in
+/// \param[in] options to pass a query key and choose which matching keys to return
+/// (FIRST, LAST or ALL)
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+///
+/// \since 8.0.0
+/// \note API not yet finalized
+ARROW_EXPORT Result<Datum> MapLookup(const Datum& map, MapLookupOptions options,
+                                     ExecContext* ctx = NULLPTR);
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/api_vector.h

@@ -0,0 +1,697 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <memory>
+#include <utility>
+
+#include "arrow/compute/function_options.h"
+#include "arrow/compute/ordering.h"
+#include "arrow/result.h"
+#include "arrow/type_fwd.h"
+
+namespace arrow {
+namespace compute {
+
+class ExecContext;
+
+/// \addtogroup compute-concrete-options
+/// @{
+
+class ARROW_EXPORT FilterOptions : public FunctionOptions {
+ public:
+  /// Configure the action taken when a slot of the selection mask is null
+  enum NullSelectionBehavior {
+    /// The corresponding filtered value will be removed in the output.
+    DROP,
+    /// The corresponding filtered value will be null in the output.
+    EMIT_NULL,
+  };
+
+  explicit FilterOptions(NullSelectionBehavior null_selection = DROP);
+  static constexpr char const kTypeName[] = "FilterOptions";
+  static FilterOptions Defaults() { return FilterOptions(); }
+
+  NullSelectionBehavior null_selection_behavior = DROP;
+};
+
+class ARROW_EXPORT TakeOptions : public FunctionOptions {
+ public:
+  explicit TakeOptions(bool boundscheck = true);
+  static constexpr char const kTypeName[] = "TakeOptions";
+  static TakeOptions BoundsCheck() { return TakeOptions(true); }
+  static TakeOptions NoBoundsCheck() { return TakeOptions(false); }
+  static TakeOptions Defaults() { return BoundsCheck(); }
+
+  bool boundscheck = true;
+};
+
+/// \brief Options for the dictionary encode function
+class ARROW_EXPORT DictionaryEncodeOptions : public FunctionOptions {
+ public:
+  /// Configure how null values will be encoded
+  enum NullEncodingBehavior {
+    /// The null value will be added to the dictionary with a proper index.
+    ENCODE,
+    /// The null value will be masked in the indices array.
+    MASK
+  };
+
+  explicit DictionaryEncodeOptions(NullEncodingBehavior null_encoding = MASK);
+  static constexpr char const kTypeName[] = "DictionaryEncodeOptions";
+  static DictionaryEncodeOptions Defaults() { return DictionaryEncodeOptions(); }
+
+  NullEncodingBehavior null_encoding_behavior = MASK;
+};
+
+/// \brief Options for the run-end encode function
+class ARROW_EXPORT RunEndEncodeOptions : public FunctionOptions {
+ public:
+  explicit RunEndEncodeOptions(std::shared_ptr<DataType> run_end_type = int32());
+  static constexpr char const kTypeName[] = "RunEndEncodeOptions";
+  static RunEndEncodeOptions Defaults() { return RunEndEncodeOptions(); }
+
+  std::shared_ptr<DataType> run_end_type;
+};
+
+class ARROW_EXPORT ArraySortOptions : public FunctionOptions {
+ public:
+  explicit ArraySortOptions(SortOrder order = SortOrder::Ascending,
+                            NullPlacement null_placement = NullPlacement::AtEnd);
+  static constexpr char const kTypeName[] = "ArraySortOptions";
+  static ArraySortOptions Defaults() { return ArraySortOptions(); }
+
+  /// Sorting order
+  SortOrder order;
+  /// Whether nulls and NaNs are placed at the start or at the end
+  NullPlacement null_placement;
+};
+
+class ARROW_EXPORT SortOptions : public FunctionOptions {
+ public:
+  explicit SortOptions(std::vector<SortKey> sort_keys = {},
+                       NullPlacement null_placement = NullPlacement::AtEnd);
+  explicit SortOptions(const Ordering& ordering);
+  static constexpr char const kTypeName[] = "SortOptions";
+  static SortOptions Defaults() { return SortOptions(); }
+  /// Convenience constructor to create an ordering from SortOptions
+  ///
+  /// Note: Both classes contain the exact same information.  However,
+  /// sort_options should only be used in a "function options" context while Ordering
+  /// is used more generally.
+  Ordering AsOrdering() && { return Ordering(std::move(sort_keys), null_placement); }
+  Ordering AsOrdering() const& { return Ordering(sort_keys, null_placement); }
+
+  /// Column key(s) to order by and how to order by these sort keys.
+  std::vector<SortKey> sort_keys;
+  /// Whether nulls and NaNs are placed at the start or at the end
+  NullPlacement null_placement;
+};
+
+/// \brief SelectK options
+class ARROW_EXPORT SelectKOptions : public FunctionOptions {
+ public:
+  explicit SelectKOptions(int64_t k = -1, std::vector<SortKey> sort_keys = {});
+  static constexpr char const kTypeName[] = "SelectKOptions";
+  static SelectKOptions Defaults() { return SelectKOptions(); }
+
+  static SelectKOptions TopKDefault(int64_t k, std::vector<std::string> key_names = {}) {
+    std::vector<SortKey> keys;
+    for (const auto& name : key_names) {
+      keys.emplace_back(SortKey(name, SortOrder::Descending));
+    }
+    if (key_names.empty()) {
+      keys.emplace_back(SortKey("not-used", SortOrder::Descending));
+    }
+    return SelectKOptions{k, keys};
+  }
+  static SelectKOptions BottomKDefault(int64_t k,
+                                       std::vector<std::string> key_names = {}) {
+    std::vector<SortKey> keys;
+    for (const auto& name : key_names) {
+      keys.emplace_back(SortKey(name, SortOrder::Ascending));
+    }
+    if (key_names.empty()) {
+      keys.emplace_back(SortKey("not-used", SortOrder::Ascending));
+    }
+    return SelectKOptions{k, keys};
+  }
+
+  /// The number of `k` elements to keep.
+  int64_t k;
+  /// Column key(s) to order by and how to order by these sort keys.
+  std::vector<SortKey> sort_keys;
+};
+
+/// \brief Rank options
+class ARROW_EXPORT RankOptions : public FunctionOptions {
+ public:
+  /// Configure how ties between equal values are handled
+  enum Tiebreaker {
+    /// Ties get the smallest possible rank in sorted order.
+    Min,
+    /// Ties get the largest possible rank in sorted order.
+    Max,
+    /// Ranks are assigned in order of when ties appear in the input.
+    /// This ensures the ranks are a stable permutation of the input.
+    First,
+    /// The ranks span a dense [1, M] interval where M is the number
+    /// of distinct values in the input.
+    Dense
+  };
+
+  explicit RankOptions(std::vector<SortKey> sort_keys = {},
+                       NullPlacement null_placement = NullPlacement::AtEnd,
+                       Tiebreaker tiebreaker = RankOptions::First);
+  /// Convenience constructor for array inputs
+  explicit RankOptions(SortOrder order,
+                       NullPlacement null_placement = NullPlacement::AtEnd,
+                       Tiebreaker tiebreaker = RankOptions::First)
+      : RankOptions({SortKey("", order)}, null_placement, tiebreaker) {}
+
+  static constexpr char const kTypeName[] = "RankOptions";
+  static RankOptions Defaults() { return RankOptions(); }
+
+  /// Column key(s) to order by and how to order by these sort keys.
+  std::vector<SortKey> sort_keys;
+  /// Whether nulls and NaNs are placed at the start or at the end
+  NullPlacement null_placement;
+  /// Tiebreaker for dealing with equal values in ranks
+  Tiebreaker tiebreaker;
+};
+
+/// \brief Partitioning options for NthToIndices
+class ARROW_EXPORT PartitionNthOptions : public FunctionOptions {
+ public:
+  explicit PartitionNthOptions(int64_t pivot,
+                               NullPlacement null_placement = NullPlacement::AtEnd);
+  PartitionNthOptions() : PartitionNthOptions(0) {}
+  static constexpr char const kTypeName[] = "PartitionNthOptions";
+
+  /// The index into the equivalent sorted array of the partition pivot element.
+  int64_t pivot;
+  /// Whether nulls and NaNs are partitioned at the start or at the end
+  NullPlacement null_placement;
+};
+
+/// \brief Options for cumulative functions
+/// \note Also aliased as CumulativeSumOptions for backward compatibility
+class ARROW_EXPORT CumulativeOptions : public FunctionOptions {
+ public:
+  explicit CumulativeOptions(bool skip_nulls = false);
+  explicit CumulativeOptions(double start, bool skip_nulls = false);
+  explicit CumulativeOptions(std::shared_ptr<Scalar> start, bool skip_nulls = false);
+  static constexpr char const kTypeName[] = "CumulativeOptions";
+  static CumulativeOptions Defaults() { return CumulativeOptions(); }
+
+  /// Optional starting value for cumulative operation computation, default depends on the
+  /// operation and input type.
+  /// - sum: 0
+  /// - prod: 1
+  /// - min: maximum of the input type
+  /// - max: minimum of the input type
+  /// - mean: start is ignored because it has no meaning for mean
+  std::optional<std::shared_ptr<Scalar>> start;
+
+  /// If true, nulls in the input are ignored and produce a corresponding null output.
+  /// When false, the first null encountered is propagated through the remaining output.
+  bool skip_nulls = false;
+};
+using CumulativeSumOptions = CumulativeOptions;  // For backward compatibility
+
+/// \brief Options for pairwise functions
+class ARROW_EXPORT PairwiseOptions : public FunctionOptions {
+ public:
+  explicit PairwiseOptions(int64_t periods = 1);
+  static constexpr char const kTypeName[] = "PairwiseOptions";
+  static PairwiseOptions Defaults() { return PairwiseOptions(); }
+
+  /// Periods to shift for applying the binary operation, accepts negative values.
+  int64_t periods = 1;
+};
+
+/// @}
+
+/// \brief Filter with a boolean selection filter
+///
+/// The output will be populated with values from the input at positions
+/// where the selection filter is not 0. Nulls in the filter will be handled
+/// based on options.null_selection_behavior.
+///
+/// For example given values = ["a", "b", "c", null, "e", "f"] and
+/// filter = [0, 1, 1, 0, null, 1], the output will be
+/// (null_selection_behavior == DROP)      = ["b", "c", "f"]
+/// (null_selection_behavior == EMIT_NULL) = ["b", "c", null, "f"]
+///
+/// \param[in] values array to filter
+/// \param[in] filter indicates which values should be filtered out
+/// \param[in] options configures null_selection_behavior
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+ARROW_EXPORT
+Result<Datum> Filter(const Datum& values, const Datum& filter,
+                     const FilterOptions& options = FilterOptions::Defaults(),
+                     ExecContext* ctx = NULLPTR);
+
+namespace internal {
+
+// These internal functions are implemented in kernels/vector_selection.cc
+
+/// \brief Return the number of selected indices in the boolean filter
+///
+/// \param filter a plain or run-end encoded boolean array with or without nulls
+/// \param null_selection how to handle nulls in the filter
+ARROW_EXPORT
+int64_t GetFilterOutputSize(const ArraySpan& filter,
+                            FilterOptions::NullSelectionBehavior null_selection);
+
+/// \brief Compute uint64 selection indices for use with Take given a boolean
+/// filter
+///
+/// \param filter a plain or run-end encoded boolean array with or without nulls
+/// \param null_selection how to handle nulls in the filter
+ARROW_EXPORT
+Result<std::shared_ptr<ArrayData>> GetTakeIndices(
+    const ArraySpan& filter, FilterOptions::NullSelectionBehavior null_selection,
+    MemoryPool* memory_pool = default_memory_pool());
+
+}  // namespace internal
+
+/// \brief ReplaceWithMask replaces each value in the array corresponding
+/// to a true value in the mask with the next element from `replacements`.
+///
+/// \param[in] values Array input to replace
+/// \param[in] mask Array or Scalar of Boolean mask values
+/// \param[in] replacements The replacement values to draw from. There must
+/// be as many replacement values as true values in the mask.
+/// \param[in] ctx the function execution context, optional
+///
+/// \return the resulting datum
+///
+/// \since 5.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> ReplaceWithMask(const Datum& values, const Datum& mask,
+                              const Datum& replacements, ExecContext* ctx = NULLPTR);
+
+/// \brief FillNullForward fill null values in forward direction
+///
+/// The output array will be of the same type as the input values
+/// array, with replaced null values in forward direction.
+///
+/// For example given values = ["a", "b", "c", null, null, "f"],
+/// the output will be = ["a", "b", "c", "c", "c", "f"]
+///
+/// \param[in] values datum from which to take
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+ARROW_EXPORT
+Result<Datum> FillNullForward(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief FillNullBackward fill null values in backward direction
+///
+/// The output array will be of the same type as the input values
+/// array, with replaced null values in backward direction.
+///
+/// For example given values = ["a", "b", "c", null, null, "f"],
+/// the output will be = ["a", "b", "c", "f", "f", "f"]
+///
+/// \param[in] values datum from which to take
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+ARROW_EXPORT
+Result<Datum> FillNullBackward(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Take from an array of values at indices in another array
+///
+/// The output array will be of the same type as the input values
+/// array, with elements taken from the values array at the given
+/// indices. If an index is null then the taken element will be null.
+///
+/// For example given values = ["a", "b", "c", null, "e", "f"] and
+/// indices = [2, 1, null, 3], the output will be
+/// = [values[2], values[1], null, values[3]]
+/// = ["c", "b", null, null]
+///
+/// \param[in] values datum from which to take
+/// \param[in] indices which values to take
+/// \param[in] options options
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+ARROW_EXPORT
+Result<Datum> Take(const Datum& values, const Datum& indices,
+                   const TakeOptions& options = TakeOptions::Defaults(),
+                   ExecContext* ctx = NULLPTR);
+
+/// \brief Take with Array inputs and output
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> Take(const Array& values, const Array& indices,
+                                    const TakeOptions& options = TakeOptions::Defaults(),
+                                    ExecContext* ctx = NULLPTR);
+
+/// \brief Drop Null from an array of values
+///
+/// The output array will be of the same type as the input values
+/// array, with elements taken from the values array without nulls.
+///
+/// For example given values = ["a", "b", "c", null, "e", "f"],
+/// the output will be = ["a", "b", "c", "e", "f"]
+///
+/// \param[in] values datum from which to take
+/// \param[in] ctx the function execution context, optional
+/// \return the resulting datum
+ARROW_EXPORT
+Result<Datum> DropNull(const Datum& values, ExecContext* ctx = NULLPTR);
+
+/// \brief DropNull with Array inputs and output
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> DropNull(const Array& values, ExecContext* ctx = NULLPTR);
+
+/// \brief Return indices that partition an array around n-th sorted element.
+///
+/// Find index of n-th(0 based) smallest value and perform indirect
+/// partition of an array around that element. Output indices[0 ~ n-1]
+/// holds values no greater than n-th element, and indices[n+1 ~ end]
+/// holds values no less than n-th element. Elements in each partition
+/// is not sorted. Nulls will be partitioned to the end of the output.
+/// Output is not guaranteed to be stable.
+///
+/// \param[in] values array to be partitioned
+/// \param[in] n pivot array around sorted n-th element
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would partition an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> NthToIndices(const Array& values, int64_t n,
+                                            ExecContext* ctx = NULLPTR);
+
+/// \brief Return indices that partition an array around n-th sorted element.
+///
+/// This overload takes a PartitionNthOptions specifying the pivot index
+/// and the null handling.
+///
+/// \param[in] values array to be partitioned
+/// \param[in] options options including pivot index and null handling
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would partition an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> NthToIndices(const Array& values,
+                                            const PartitionNthOptions& options,
+                                            ExecContext* ctx = NULLPTR);
+
+/// \brief Return indices that would select the first `k` elements.
+///
+/// Perform an indirect sort of the datum, keeping only the first `k` elements. The output
+/// array will contain indices such that the item indicated by the k-th index will be in
+/// the position it would be if the datum were sorted by `options.sort_keys`. However,
+/// indices of null values will not be part of the output. The sort is not guaranteed to
+/// be stable.
+///
+/// \param[in] datum datum to be partitioned
+/// \param[in] options options
+/// \param[in] ctx the function execution context, optional
+/// \return a datum with the same schema as the input
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SelectKUnstable(const Datum& datum,
+                                               const SelectKOptions& options,
+                                               ExecContext* ctx = NULLPTR);
+
+/// \brief Return the indices that would sort an array.
+///
+/// Perform an indirect sort of array. The output array will contain
+/// indices that would sort an array, which would be the same length
+/// as input. Nulls will be stably partitioned to the end of the output
+/// regardless of order.
+///
+/// For example given array = [null, 1, 3.3, null, 2, 5.3] and order
+/// = SortOrder::DESCENDING, the output will be [5, 2, 4, 1, 0,
+/// 3].
+///
+/// \param[in] array array to sort
+/// \param[in] order ascending or descending
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would sort an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SortIndices(const Array& array,
+                                           SortOrder order = SortOrder::Ascending,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Return the indices that would sort an array.
+///
+/// This overload takes a ArraySortOptions specifying the sort order
+/// and the null handling.
+///
+/// \param[in] array array to sort
+/// \param[in] options options including sort order and null handling
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would sort an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SortIndices(const Array& array,
+                                           const ArraySortOptions& options,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Return the indices that would sort a chunked array.
+///
+/// Perform an indirect sort of chunked array. The output array will
+/// contain indices that would sort a chunked array, which would be
+/// the same length as input. Nulls will be stably partitioned to the
+/// end of the output regardless of order.
+///
+/// For example given chunked_array = [[null, 1], [3.3], [null, 2,
+/// 5.3]] and order = SortOrder::DESCENDING, the output will be [5, 2,
+/// 4, 1, 0, 3].
+///
+/// \param[in] chunked_array chunked array to sort
+/// \param[in] order ascending or descending
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would sort an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SortIndices(const ChunkedArray& chunked_array,
+                                           SortOrder order = SortOrder::Ascending,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Return the indices that would sort a chunked array.
+///
+/// This overload takes a ArraySortOptions specifying the sort order
+/// and the null handling.
+///
+/// \param[in] chunked_array chunked array to sort
+/// \param[in] options options including sort order and null handling
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would sort an array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SortIndices(const ChunkedArray& chunked_array,
+                                           const ArraySortOptions& options,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Return the indices that would sort an input in the
+/// specified order. Input is one of array, chunked array record batch
+/// or table.
+///
+/// Perform an indirect sort of input. The output array will contain
+/// indices that would sort an input, which would be the same length
+/// as input. Nulls will be stably partitioned to the start or to the end
+/// of the output depending on SortOrder::null_placement.
+///
+/// For example given input (table) = {
+/// "column1": [[null,   1], [   3, null, 2, 1]],
+/// "column2": [[   5], [3,   null, null, 5, 5]],
+/// } and options = {
+/// {"column1", SortOrder::Ascending},
+/// {"column2", SortOrder::Descending},
+/// }, the output will be [5, 1, 4, 2, 0, 3].
+///
+/// \param[in] datum array, chunked array, record batch or table to sort
+/// \param[in] options options
+/// \param[in] ctx the function execution context, optional
+/// \return offsets indices that would sort a table
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> SortIndices(const Datum& datum, const SortOptions& options,
+                                           ExecContext* ctx = NULLPTR);
+
+/// \brief Compute unique elements from an array-like object
+///
+/// Note if a null occurs in the input it will NOT be included in the output.
+///
+/// \param[in] datum array-like input
+/// \param[in] ctx the function execution context, optional
+/// \return result as Array
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> Unique(const Datum& datum, ExecContext* ctx = NULLPTR);
+
+// Constants for accessing the output of ValueCounts
+ARROW_EXPORT extern const char kValuesFieldName[];
+ARROW_EXPORT extern const char kCountsFieldName[];
+ARROW_EXPORT extern const int32_t kValuesFieldIndex;
+ARROW_EXPORT extern const int32_t kCountsFieldIndex;
+
+/// \brief Return counts of unique elements from an array-like object.
+///
+/// Note that the counts do not include counts for nulls in the array.  These can be
+/// obtained separately from metadata.
+///
+/// For floating point arrays there is no attempt to normalize -0.0, 0.0 and NaN values
+/// which can lead to unexpected results if the input Array has these values.
+///
+/// \param[in] value array-like input
+/// \param[in] ctx the function execution context, optional
+/// \return counts An array of  <input type "Values", int64_t "Counts"> structs.
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<std::shared_ptr<StructArray>> ValueCounts(const Datum& value,
+                                                 ExecContext* ctx = NULLPTR);
+
+/// \brief Dictionary-encode values in an array-like object
+///
+/// Any nulls encountered in the dictionary will be handled according to the
+/// specified null encoding behavior.
+///
+/// For example, given values ["a", "b", null, "a", null] the output will be
+/// (null_encoding == ENCODE) Indices: [0, 1, 2, 0, 2] / Dict: ["a", "b", null]
+/// (null_encoding == MASK)   Indices: [0, 1, null, 0, null] / Dict: ["a", "b"]
+///
+/// If the input is already dictionary encoded this function is a no-op unless
+/// it needs to modify the null_encoding (TODO)
+///
+/// \param[in] data array-like input
+/// \param[in] ctx the function execution context, optional
+/// \param[in] options configures null encoding behavior
+/// \return result with same shape and type as input
+///
+/// \since 1.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> DictionaryEncode(
+    const Datum& data,
+    const DictionaryEncodeOptions& options = DictionaryEncodeOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Run-end-encode values in an array-like object
+///
+/// The returned run-end encoded type uses the same value type of the input and
+/// run-end type defined in the options.
+///
+/// \param[in] value array-like input
+/// \param[in] options configures encoding behavior
+/// \param[in] ctx the function execution context, optional
+/// \return result with same shape but run-end encoded
+///
+/// \since 12.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> RunEndEncode(
+    const Datum& value,
+    const RunEndEncodeOptions& options = RunEndEncodeOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Decode a Run-End Encoded array to a plain array
+///
+/// The output data type is the same as the values array type of run-end encoded
+/// input.
+///
+/// \param[in] value run-end-encoded input
+/// \param[in] ctx the function execution context, optional
+/// \return plain array resulting from decoding the run-end encoded input
+///
+/// \since 12.0.0
+/// \note API not yet finalized
+ARROW_EXPORT
+Result<Datum> RunEndDecode(const Datum& value, ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cumulative sum of an array-like object
+///
+/// \param[in] values array-like input
+/// \param[in] options configures cumulative sum behavior
+/// \param[in] check_overflow whether to check for overflow, if true, return Invalid
+/// status on overflow, otherwise wrap around on overflow
+/// \param[in] ctx the function execution context, optional
+ARROW_EXPORT
+Result<Datum> CumulativeSum(
+    const Datum& values, const CumulativeOptions& options = CumulativeOptions::Defaults(),
+    bool check_overflow = false, ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cumulative product of an array-like object
+///
+/// \param[in] values array-like input
+/// \param[in] options configures cumulative prod behavior
+/// \param[in] check_overflow whether to check for overflow, if true, return Invalid
+/// status on overflow, otherwise wrap around on overflow
+/// \param[in] ctx the function execution context, optional
+ARROW_EXPORT
+Result<Datum> CumulativeProd(
+    const Datum& values, const CumulativeOptions& options = CumulativeOptions::Defaults(),
+    bool check_overflow = false, ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cumulative max of an array-like object
+///
+/// \param[in] values array-like input
+/// \param[in] options configures cumulative max behavior
+/// \param[in] ctx the function execution context, optional
+ARROW_EXPORT
+Result<Datum> CumulativeMax(
+    const Datum& values, const CumulativeOptions& options = CumulativeOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cumulative min of an array-like object
+///
+/// \param[in] values array-like input
+/// \param[in] options configures cumulative min behavior
+/// \param[in] ctx the function execution context, optional
+ARROW_EXPORT
+Result<Datum> CumulativeMin(
+    const Datum& values, const CumulativeOptions& options = CumulativeOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Compute the cumulative mean of an array-like object
+///
+/// \param[in] values array-like input
+/// \param[in] options configures cumulative mean behavior, `start` is ignored
+/// \param[in] ctx the function execution context, optional
+ARROW_EXPORT
+Result<Datum> CumulativeMean(
+    const Datum& values, const CumulativeOptions& options = CumulativeOptions::Defaults(),
+    ExecContext* ctx = NULLPTR);
+
+/// \brief Return the first order difference of an array.
+///
+/// Computes the first order difference of an array, i.e.
+///   output[i] = input[i] - input[i - p]  if i >= p
+///   output[i] = null                     otherwise
+/// where p is the period. For example, with p = 1,
+///   Diff([1, 4, 9, 10, 15]) = [null, 3, 5, 1, 5].
+/// With p = 2,
+///   Diff([1, 4, 9, 10, 15]) = [null, null, 8, 6, 6]
+/// p can also be negative, in which case the diff is computed in
+/// the opposite direction.
+/// \param[in] array array input
+/// \param[in] options options, specifying overflow behavior and period
+/// \param[in] check_overflow whether to return error on overflow
+/// \param[in] ctx the function execution context, optional
+/// \return result as array
+ARROW_EXPORT
+Result<std::shared_ptr<Array>> PairwiseDiff(const Array& array,
+                                            const PairwiseOptions& options,
+                                            bool check_overflow = false,
+                                            ExecContext* ctx = NULLPTR);
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/exec.h

@@ -0,0 +1,489 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// NOTE: API is EXPERIMENTAL and will change without going through a
+// deprecation cycle
+
+#pragma once
+
+#include <atomic>
+#include <cstdint>
+#include <limits>
+#include <memory>
+#include <optional>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "arrow/array/data.h"
+#include "arrow/compute/expression.h"
+#include "arrow/compute/type_fwd.h"
+#include "arrow/datum.h"
+#include "arrow/result.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/type_fwd.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace compute {
+
+// It seems like 64K might be a good default chunksize to use for execution
+// based on the experience of other query processing systems. The current
+// default is not to chunk contiguous arrays, though, but this may change in
+// the future once parallel execution is implemented
+static constexpr int64_t kDefaultExecChunksize = UINT16_MAX;
+
+/// \brief Context for expression-global variables and options used by
+/// function evaluation
+class ARROW_EXPORT ExecContext {
+ public:
+  // If no function registry passed, the default is used.
+  explicit ExecContext(MemoryPool* pool = default_memory_pool(),
+                       ::arrow::internal::Executor* executor = NULLPTR,
+                       FunctionRegistry* func_registry = NULLPTR);
+
+  /// \brief The MemoryPool used for allocations, default is
+  /// default_memory_pool().
+  MemoryPool* memory_pool() const { return pool_; }
+
+  const ::arrow::internal::CpuInfo* cpu_info() const;
+
+  /// \brief An Executor which may be used to parallelize execution.
+  ::arrow::internal::Executor* executor() const { return executor_; }
+
+  /// \brief The FunctionRegistry for looking up functions by name and
+  /// selecting kernels for execution. Defaults to the library-global function
+  /// registry provided by GetFunctionRegistry.
+  FunctionRegistry* func_registry() const { return func_registry_; }
+
+  // \brief Set maximum length unit of work for kernel execution. Larger
+  // contiguous array inputs will be split into smaller chunks, and, if
+  // possible and enabled, processed in parallel. The default chunksize is
+  // INT64_MAX, so contiguous arrays are not split.
+  void set_exec_chunksize(int64_t chunksize) { exec_chunksize_ = chunksize; }
+
+  // \brief Maximum length for ExecBatch data chunks processed by
+  // kernels. Contiguous array inputs with longer length will be split into
+  // smaller chunks.
+  int64_t exec_chunksize() const { return exec_chunksize_; }
+
+  /// \brief Set whether to use multiple threads for function execution. This
+  /// is not yet used.
+  void set_use_threads(bool use_threads = true) { use_threads_ = use_threads; }
+
+  /// \brief If true, then utilize multiple threads where relevant for function
+  /// execution. This is not yet used.
+  bool use_threads() const { return use_threads_; }
+
+  // Set the preallocation strategy for kernel execution as it relates to
+  // chunked execution. For chunked execution, whether via ChunkedArray inputs
+  // or splitting larger Array arguments into smaller pieces, contiguous
+  // allocation (if permitted by the kernel) will allocate one large array to
+  // write output into yielding it to the caller at the end. If this option is
+  // set to off, then preallocations will be performed independently for each
+  // chunk of execution
+  //
+  // TODO: At some point we might want the limit the size of contiguous
+  // preallocations. For example, even if the exec_chunksize is 64K or less, we
+  // might limit contiguous allocations to 1M records, say.
+  void set_preallocate_contiguous(bool preallocate) {
+    preallocate_contiguous_ = preallocate;
+  }
+
+  /// \brief If contiguous preallocations should be used when doing chunked
+  /// execution as specified by exec_chunksize(). See
+  /// set_preallocate_contiguous() for more information.
+  bool preallocate_contiguous() const { return preallocate_contiguous_; }
+
+ private:
+  MemoryPool* pool_;
+  ::arrow::internal::Executor* executor_;
+  FunctionRegistry* func_registry_;
+  int64_t exec_chunksize_ = std::numeric_limits<int64_t>::max();
+  bool preallocate_contiguous_ = true;
+  bool use_threads_ = true;
+};
+
+// TODO: Consider standardizing on uint16 selection vectors and only use them
+// when we can ensure that each value is 64K length or smaller
+
+/// \brief Container for an array of value selection indices that were
+/// materialized from a filter.
+///
+/// Columnar query engines (see e.g. [1]) have found that rather than
+/// materializing filtered data, the filter can instead be converted to an
+/// array of the "on" indices and then "fusing" these indices in operator
+/// implementations. This is especially relevant for aggregations but also
+/// applies to scalar operations.
+///
+/// We are not yet using this so this is mostly a placeholder for now.
+///
+/// [1]: http://cidrdb.org/cidr2005/papers/P19.pdf
+class ARROW_EXPORT SelectionVector {
+ public:
+  explicit SelectionVector(std::shared_ptr<ArrayData> data);
+
+  explicit SelectionVector(const Array& arr);
+
+  /// \brief Create SelectionVector from boolean mask
+  static Result<std::shared_ptr<SelectionVector>> FromMask(const BooleanArray& arr);
+
+  const int32_t* indices() const { return indices_; }
+  int32_t length() const;
+
+ private:
+  std::shared_ptr<ArrayData> data_;
+  const int32_t* indices_;
+};
+
+/// An index to represent that a batch does not belong to an ordered stream
+constexpr int64_t kUnsequencedIndex = -1;
+
+/// \brief A unit of work for kernel execution. It contains a collection of
+/// Array and Scalar values and an optional SelectionVector indicating that
+/// there is an unmaterialized filter that either must be materialized, or (if
+/// the kernel supports it) pushed down into the kernel implementation.
+///
+/// ExecBatch is semantically similar to RecordBatch in that in a SQL context
+/// it represents a collection of records, but constant "columns" are
+/// represented by Scalar values rather than having to be converted into arrays
+/// with repeated values.
+///
+/// TODO: Datum uses arrow/util/variant.h which may be a bit heavier-weight
+/// than is desirable for this class. Microbenchmarks would help determine for
+/// sure. See ARROW-8928.
+
+/// \addtogroup acero-internals
+/// @{
+
+struct ARROW_EXPORT ExecBatch {
+  ExecBatch() = default;
+  ExecBatch(std::vector<Datum> values, int64_t length)
+      : values(std::move(values)), length(length) {}
+
+  explicit ExecBatch(const RecordBatch& batch);
+
+  /// \brief Infer the ExecBatch length from values.
+  static Result<int64_t> InferLength(const std::vector<Datum>& values);
+
+  /// Creates an ExecBatch with length-validation.
+  ///
+  /// If any value is given, then all values must have a common length. If the given
+  /// length is negative, then the length of the ExecBatch is set to this common length,
+  /// or to 1 if no values are given. Otherwise, the given length must equal the common
+  /// length, if any value is given.
+  static Result<ExecBatch> Make(std::vector<Datum> values, int64_t length = -1);
+
+  Result<std::shared_ptr<RecordBatch>> ToRecordBatch(
+      std::shared_ptr<Schema> schema, MemoryPool* pool = default_memory_pool()) const;
+
+  /// The values representing positional arguments to be passed to a kernel's
+  /// exec function for processing.
+  std::vector<Datum> values;
+
+  /// A deferred filter represented as an array of indices into the values.
+  ///
+  /// For example, the filter [true, true, false, true] would be represented as
+  /// the selection vector [0, 1, 3]. When the selection vector is set,
+  /// ExecBatch::length is equal to the length of this array.
+  std::shared_ptr<SelectionVector> selection_vector;
+
+  /// A predicate Expression guaranteed to evaluate to true for all rows in this batch.
+  Expression guarantee = literal(true);
+
+  /// The semantic length of the ExecBatch. When the values are all scalars,
+  /// the length should be set to 1 for non-aggregate kernels, otherwise the
+  /// length is taken from the array values, except when there is a selection
+  /// vector. When there is a selection vector set, the length of the batch is
+  /// the length of the selection. Aggregate kernels can have an ExecBatch
+  /// formed by projecting just the partition columns from a batch in which
+  /// case, it would have scalar rows with length greater than 1.
+  ///
+  /// If the array values are of length 0 then the length is 0 regardless of
+  /// whether any values are Scalar.
+  int64_t length = 0;
+
+  /// \brief index of this batch in a sorted stream of batches
+  ///
+  /// This index must be strictly monotonic starting at 0 without gaps or
+  /// it can be set to kUnsequencedIndex if there is no meaningful order
+  int64_t index = kUnsequencedIndex;
+
+  /// \brief The sum of bytes in each buffer referenced by the batch
+  ///
+  /// Note: Scalars are not counted
+  /// Note: Some values may referenced only part of a buffer, for
+  ///       example, an array with an offset.  The actual data
+  ///       visible to this batch will be smaller than the total
+  ///       buffer size in this case.
+  int64_t TotalBufferSize() const;
+
+  /// \brief Return the value at the i-th index
+  template <typename index_type>
+  inline const Datum& operator[](index_type i) const {
+    return values[i];
+  }
+
+  bool Equals(const ExecBatch& other) const;
+
+  /// \brief A convenience for the number of values / arguments.
+  int num_values() const { return static_cast<int>(values.size()); }
+
+  ExecBatch Slice(int64_t offset, int64_t length) const;
+
+  Result<ExecBatch> SelectValues(const std::vector<int>& ids) const;
+
+  /// \brief A convenience for returning the types from the batch.
+  std::vector<TypeHolder> GetTypes() const {
+    std::vector<TypeHolder> result;
+    for (const auto& value : this->values) {
+      result.emplace_back(value.type());
+    }
+    return result;
+  }
+
+  std::string ToString() const;
+};
+
+inline bool operator==(const ExecBatch& l, const ExecBatch& r) { return l.Equals(r); }
+inline bool operator!=(const ExecBatch& l, const ExecBatch& r) { return !l.Equals(r); }
+
+ARROW_EXPORT void PrintTo(const ExecBatch&, std::ostream*);
+
+/// @}
+
+/// \defgroup compute-internals Utilities for calling functions, useful for those
+/// extending the function registry
+///
+/// @{
+
+struct ExecValue {
+  ArraySpan array = {};
+  const Scalar* scalar = NULLPTR;
+
+  ExecValue(Scalar* scalar)  // NOLINT implicit conversion
+      : scalar(scalar) {}
+
+  ExecValue(ArraySpan array)  // NOLINT implicit conversion
+      : array(std::move(array)) {}
+
+  ExecValue(const ArrayData& array) {  // NOLINT implicit conversion
+    this->array.SetMembers(array);
+  }
+
+  ExecValue() = default;
+  ExecValue(const ExecValue& other) = default;
+  ExecValue& operator=(const ExecValue& other) = default;
+  ExecValue(ExecValue&& other) = default;
+  ExecValue& operator=(ExecValue&& other) = default;
+
+  int64_t length() const { return this->is_array() ? this->array.length : 1; }
+
+  bool is_array() const { return this->scalar == NULLPTR; }
+  bool is_scalar() const { return !this->is_array(); }
+
+  void SetArray(const ArrayData& array) {
+    this->array.SetMembers(array);
+    this->scalar = NULLPTR;
+  }
+
+  void SetScalar(const Scalar* scalar) { this->scalar = scalar; }
+
+  template <typename ExactType>
+  const ExactType& scalar_as() const {
+    return ::arrow::internal::checked_cast<const ExactType&>(*this->scalar);
+  }
+
+  /// XXX: here temporarily for compatibility with datum, see
+  /// e.g. MakeStructExec in scalar_nested.cc
+  int64_t null_count() const {
+    if (this->is_array()) {
+      return this->array.GetNullCount();
+    } else {
+      return this->scalar->is_valid ? 0 : 1;
+    }
+  }
+
+  const DataType* type() const {
+    if (this->is_array()) {
+      return array.type;
+    } else {
+      return scalar->type.get();
+    }
+  }
+};
+
+struct ARROW_EXPORT ExecResult {
+  // The default value of the variant is ArraySpan
+  std::variant<ArraySpan, std::shared_ptr<ArrayData>> value;
+
+  int64_t length() const {
+    if (this->is_array_span()) {
+      return this->array_span()->length;
+    } else {
+      return this->array_data()->length;
+    }
+  }
+
+  const DataType* type() const {
+    if (this->is_array_span()) {
+      return this->array_span()->type;
+    } else {
+      return this->array_data()->type.get();
+    }
+  }
+
+  const ArraySpan* array_span() const { return &std::get<ArraySpan>(this->value); }
+  ArraySpan* array_span_mutable() { return &std::get<ArraySpan>(this->value); }
+
+  bool is_array_span() const { return this->value.index() == 0; }
+
+  const std::shared_ptr<ArrayData>& array_data() const {
+    return std::get<std::shared_ptr<ArrayData>>(this->value);
+  }
+  ArrayData* array_data_mutable() {
+    return std::get<std::shared_ptr<ArrayData>>(this->value).get();
+  }
+
+  bool is_array_data() const { return this->value.index() == 1; }
+};
+
+/// \brief A "lightweight" column batch object which contains no
+/// std::shared_ptr objects and does not have any memory ownership
+/// semantics. Can represent a view onto an "owning" ExecBatch.
+struct ARROW_EXPORT ExecSpan {
+  ExecSpan() = default;
+  ExecSpan(const ExecSpan& other) = default;
+  ExecSpan& operator=(const ExecSpan& other) = default;
+  ExecSpan(ExecSpan&& other) = default;
+  ExecSpan& operator=(ExecSpan&& other) = default;
+
+  explicit ExecSpan(std::vector<ExecValue> values, int64_t length)
+      : length(length), values(std::move(values)) {}
+
+  explicit ExecSpan(const ExecBatch& batch) {
+    this->length = batch.length;
+    this->values.resize(batch.values.size());
+    for (size_t i = 0; i < batch.values.size(); ++i) {
+      const Datum& in_value = batch[i];
+      ExecValue* out_value = &this->values[i];
+      if (in_value.is_array()) {
+        out_value->SetArray(*in_value.array());
+      } else {
+        out_value->SetScalar(in_value.scalar().get());
+      }
+    }
+  }
+
+  /// \brief Return the value at the i-th index
+  template <typename index_type>
+  inline const ExecValue& operator[](index_type i) const {
+    return values[i];
+  }
+
+  /// \brief A convenience for the number of values / arguments.
+  int num_values() const { return static_cast<int>(values.size()); }
+
+  std::vector<TypeHolder> GetTypes() const {
+    std::vector<TypeHolder> result;
+    for (const auto& value : this->values) {
+      result.emplace_back(value.type());
+    }
+    return result;
+  }
+
+  ExecBatch ToExecBatch() const {
+    ExecBatch result;
+    result.length = this->length;
+    for (const ExecValue& value : this->values) {
+      if (value.is_array()) {
+        result.values.push_back(value.array.ToArrayData());
+      } else {
+        result.values.push_back(value.scalar->GetSharedPtr());
+      }
+    }
+    return result;
+  }
+
+  int64_t length = 0;
+  std::vector<ExecValue> values;
+};
+
+/// \defgroup compute-call-function One-shot calls to compute functions
+///
+/// @{
+
+/// \brief One-shot invoker for all types of functions.
+///
+/// Does kernel dispatch, argument checking, iteration of ChunkedArray inputs,
+/// and wrapping of outputs.
+ARROW_EXPORT
+Result<Datum> CallFunction(const std::string& func_name, const std::vector<Datum>& args,
+                           const FunctionOptions* options, ExecContext* ctx = NULLPTR);
+
+/// \brief Variant of CallFunction which uses a function's default options.
+///
+/// NB: Some functions require FunctionOptions be provided.
+ARROW_EXPORT
+Result<Datum> CallFunction(const std::string& func_name, const std::vector<Datum>& args,
+                           ExecContext* ctx = NULLPTR);
+
+/// \brief One-shot invoker for all types of functions.
+///
+/// Does kernel dispatch, argument checking, iteration of ChunkedArray inputs,
+/// and wrapping of outputs.
+ARROW_EXPORT
+Result<Datum> CallFunction(const std::string& func_name, const ExecBatch& batch,
+                           const FunctionOptions* options, ExecContext* ctx = NULLPTR);
+
+/// \brief Variant of CallFunction which uses a function's default options.
+///
+/// NB: Some functions require FunctionOptions be provided.
+ARROW_EXPORT
+Result<Datum> CallFunction(const std::string& func_name, const ExecBatch& batch,
+                           ExecContext* ctx = NULLPTR);
+
+/// @}
+
+/// \defgroup compute-function-executor One-shot calls to obtain function executors
+///
+/// @{
+
+/// \brief One-shot executor provider for all types of functions.
+///
+/// This function creates and initializes a `FunctionExecutor` appropriate
+/// for the given function name, input types and function options.
+ARROW_EXPORT
+Result<std::shared_ptr<FunctionExecutor>> GetFunctionExecutor(
+    const std::string& func_name, std::vector<TypeHolder> in_types,
+    const FunctionOptions* options = NULLPTR, FunctionRegistry* func_registry = NULLPTR);
+
+/// \brief One-shot executor provider for all types of functions.
+///
+/// This function creates and initializes a `FunctionExecutor` appropriate
+/// for the given function name, input types (taken from the Datum arguments)
+/// and function options.
+ARROW_EXPORT
+Result<std::shared_ptr<FunctionExecutor>> GetFunctionExecutor(
+    const std::string& func_name, const std::vector<Datum>& args,
+    const FunctionOptions* options = NULLPTR, FunctionRegistry* func_registry = NULLPTR);
+
+/// @}
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/expression.h

@@ -0,0 +1,295 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// This API is EXPERIMENTAL.
+
+#pragma once
+
+#include <memory>
+#include <string>
+#include <utility>
+#include <variant>
+#include <vector>
+
+#include "arrow/compute/type_fwd.h"
+#include "arrow/datum.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/small_vector.h"
+
+namespace arrow {
+namespace compute {
+
+/// \defgroup expression-core Expressions to describe data transformations
+///
+/// @{
+
+/// An unbound expression which maps a single Datum to another Datum.
+/// An expression is one of
+/// - A literal Datum.
+/// - A reference to a single (potentially nested) field of the input Datum.
+/// - A call to a compute function, with arguments specified by other Expressions.
+class ARROW_EXPORT Expression {
+ public:
+  struct Call {
+    std::string function_name;
+    std::vector<Expression> arguments;
+    std::shared_ptr<FunctionOptions> options;
+    // Cached hash value
+    size_t hash;
+
+    // post-Bind properties:
+    std::shared_ptr<Function> function;
+    const Kernel* kernel = NULLPTR;
+    std::shared_ptr<KernelState> kernel_state;
+    TypeHolder type;
+
+    void ComputeHash();
+  };
+
+  std::string ToString() const;
+  bool Equals(const Expression& other) const;
+  size_t hash() const;
+  struct Hash {
+    size_t operator()(const Expression& expr) const { return expr.hash(); }
+  };
+
+  /// Bind this expression to the given input type, looking up Kernels and field types.
+  /// Some expression simplification may be performed and implicit casts will be inserted.
+  /// Any state necessary for execution will be initialized and returned.
+  Result<Expression> Bind(const TypeHolder& in, ExecContext* = NULLPTR) const;
+  Result<Expression> Bind(const Schema& in_schema, ExecContext* = NULLPTR) const;
+
+  // XXX someday
+  // Clone all KernelState in this bound expression. If any function referenced by this
+  // expression has mutable KernelState, it is not safe to execute or apply simplification
+  // passes to it (or copies of it!) from multiple threads. Cloning state produces new
+  // KernelStates where necessary to ensure that Expressions may be manipulated safely
+  // on multiple threads.
+  // Result<ExpressionState> CloneState() const;
+  // Status SetState(ExpressionState);
+
+  /// Return true if all an expression's field references have explicit types
+  /// and all of its functions' kernels are looked up.
+  bool IsBound() const;
+
+  /// Return true if this expression is composed only of Scalar literals, field
+  /// references, and calls to ScalarFunctions.
+  bool IsScalarExpression() const;
+
+  /// Return true if this expression is literal and entirely null.
+  bool IsNullLiteral() const;
+
+  /// Return true if this expression could evaluate to true. Will return true for any
+  /// unbound or non-boolean Expressions. IsSatisfiable does not (currently) do any
+  /// canonicalization or simplification of the expression, so even Expressions
+  /// which are unsatisfiable may spuriously return `true` here. This function is
+  /// intended for use in predicate pushdown where a filter expression is simplified
+  /// by a guarantee, so it assumes that trying to simplify again would be redundant.
+  bool IsSatisfiable() const;
+
+  // XXX someday
+  // Result<PipelineGraph> GetPipelines();
+
+  bool is_valid() const { return impl_ != NULLPTR; }
+
+  /// Access a Call or return nullptr if this expression is not a call
+  const Call* call() const;
+  /// Access a Datum or return nullptr if this expression is not a literal
+  const Datum* literal() const;
+  /// Access a FieldRef or return nullptr if this expression is not a field_ref
+  const FieldRef* field_ref() const;
+
+  /// The type to which this expression will evaluate
+  const DataType* type() const;
+  // XXX someday
+  // NullGeneralization::type nullable() const;
+
+  struct Parameter {
+    FieldRef ref;
+
+    // post-bind properties
+    TypeHolder type;
+    ::arrow::internal::SmallVector<int, 2> indices;
+  };
+  const Parameter* parameter() const;
+
+  Expression() = default;
+  explicit Expression(Call call);
+  explicit Expression(Datum literal);
+  explicit Expression(Parameter parameter);
+
+ private:
+  using Impl = std::variant<Datum, Parameter, Call>;
+  std::shared_ptr<Impl> impl_;
+
+  ARROW_FRIEND_EXPORT friend bool Identical(const Expression& l, const Expression& r);
+};
+
+inline bool operator==(const Expression& l, const Expression& r) { return l.Equals(r); }
+inline bool operator!=(const Expression& l, const Expression& r) { return !l.Equals(r); }
+
+ARROW_EXPORT void PrintTo(const Expression&, std::ostream*);
+
+// Factories
+
+ARROW_EXPORT
+Expression literal(Datum lit);
+
+template <typename Arg>
+Expression literal(Arg&& arg) {
+  return literal(Datum(std::forward<Arg>(arg)));
+}
+
+ARROW_EXPORT
+Expression field_ref(FieldRef ref);
+
+ARROW_EXPORT
+Expression call(std::string function, std::vector<Expression> arguments,
+                std::shared_ptr<FunctionOptions> options = NULLPTR);
+
+template <typename Options, typename = typename std::enable_if<
+                                std::is_base_of<FunctionOptions, Options>::value>::type>
+Expression call(std::string function, std::vector<Expression> arguments,
+                Options options) {
+  return call(std::move(function), std::move(arguments),
+              std::make_shared<Options>(std::move(options)));
+}
+
+/// Assemble a list of all fields referenced by an Expression at any depth.
+ARROW_EXPORT
+std::vector<FieldRef> FieldsInExpression(const Expression&);
+
+/// Check if the expression references any fields.
+ARROW_EXPORT
+bool ExpressionHasFieldRefs(const Expression&);
+
+struct ARROW_EXPORT KnownFieldValues;
+
+/// Assemble a mapping from field references to known values. This derives known values
+/// from "equal" and "is_null" Expressions referencing a field and a literal.
+ARROW_EXPORT
+Result<KnownFieldValues> ExtractKnownFieldValues(
+    const Expression& guaranteed_true_predicate);
+
+/// @}
+
+/// \defgroup expression-passes Functions for modification of Expressions
+///
+/// @{
+///
+/// These transform bound expressions. Some transforms utilize a guarantee, which is
+/// provided as an Expression which is guaranteed to evaluate to true. The
+/// guaranteed_true_predicate need not be bound, but canonicalization is currently
+/// deferred to producers of guarantees. For example in order to be recognized as a
+/// guarantee on a field value, an Expression must be a call to "equal" with field_ref LHS
+/// and literal RHS. Flipping the arguments, "is_in" with a one-long value_set, ... or
+/// other semantically identical Expressions will not be recognized.
+
+/// Weak canonicalization which establishes guarantees for subsequent passes. Even
+/// equivalent Expressions may result in different canonicalized expressions.
+/// TODO this could be a strong canonicalization
+ARROW_EXPORT
+Result<Expression> Canonicalize(Expression, ExecContext* = NULLPTR);
+
+/// Simplify Expressions based on literal arguments (for example, add(null, x) will always
+/// be null so replace the call with a null literal). Includes early evaluation of all
+/// calls whose arguments are entirely literal.
+ARROW_EXPORT
+Result<Expression> FoldConstants(Expression);
+
+/// Simplify Expressions by replacing with known values of the fields which it references.
+ARROW_EXPORT
+Result<Expression> ReplaceFieldsWithKnownValues(const KnownFieldValues& known_values,
+                                                Expression);
+
+/// Simplify an expression by replacing subexpressions based on a guarantee:
+/// a boolean expression which is guaranteed to evaluate to `true`. For example, this is
+/// used to remove redundant function calls from a filter expression or to replace a
+/// reference to a constant-value field with a literal.
+ARROW_EXPORT
+Result<Expression> SimplifyWithGuarantee(Expression,
+                                         const Expression& guaranteed_true_predicate);
+
+/// Replace all named field refs (e.g. "x" or "x.y") with field paths (e.g. [0] or [1,3])
+///
+/// This isn't usually needed and does not offer any simplification by itself.  However,
+/// it can be useful to normalize an expression to paths to make it simpler to work with.
+ARROW_EXPORT Result<Expression> RemoveNamedRefs(Expression expression);
+
+/// @}
+
+// Execution
+
+/// Create an ExecBatch suitable for passing to ExecuteScalarExpression() from a
+/// RecordBatch which may have missing or incorrectly ordered columns.
+/// Missing fields will be replaced with null scalars.
+ARROW_EXPORT Result<ExecBatch> MakeExecBatch(const Schema& full_schema,
+                                             const Datum& partial,
+                                             Expression guarantee = literal(true));
+
+/// Execute a scalar expression against the provided state and input ExecBatch. This
+/// expression must be bound.
+ARROW_EXPORT
+Result<Datum> ExecuteScalarExpression(const Expression&, const ExecBatch& input,
+                                      ExecContext* = NULLPTR);
+
+/// Convenience function for invoking against a RecordBatch
+ARROW_EXPORT
+Result<Datum> ExecuteScalarExpression(const Expression&, const Schema& full_schema,
+                                      const Datum& partial_input, ExecContext* = NULLPTR);
+
+// Serialization
+
+ARROW_EXPORT
+Result<std::shared_ptr<Buffer>> Serialize(const Expression&);
+
+ARROW_EXPORT
+Result<Expression> Deserialize(std::shared_ptr<Buffer>);
+
+/// \defgroup expression-convenience Helpers for convenient expression creation
+///
+/// @{
+
+ARROW_EXPORT Expression project(std::vector<Expression> values,
+                                std::vector<std::string> names);
+
+ARROW_EXPORT Expression equal(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression not_equal(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression less(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression less_equal(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression greater(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression greater_equal(Expression lhs, Expression rhs);
+
+ARROW_EXPORT Expression is_null(Expression lhs, bool nan_is_null = false);
+
+ARROW_EXPORT Expression is_valid(Expression lhs);
+
+ARROW_EXPORT Expression and_(Expression lhs, Expression rhs);
+ARROW_EXPORT Expression and_(const std::vector<Expression>&);
+ARROW_EXPORT Expression or_(Expression lhs, Expression rhs);
+ARROW_EXPORT Expression or_(const std::vector<Expression>&);
+ARROW_EXPORT Expression not_(Expression operand);
+
+/// @}
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/kernel.h

@@ -0,0 +1,752 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// NOTE: API is EXPERIMENTAL and will change without going through a
+// deprecation cycle
+
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "arrow/buffer.h"
+#include "arrow/compute/exec.h"
+#include "arrow/datum.h"
+#include "arrow/memory_pool.h"
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/type.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+// macOS defines PREALLOCATE as a preprocessor macro in the header sys/vnode.h.
+// No other BSD seems to do so. The name is used as an identifier in MemAllocation enum.
+#if defined(__APPLE__) && defined(PREALLOCATE)
+#undef PREALLOCATE
+#endif
+
+namespace arrow {
+namespace compute {
+
+class FunctionOptions;
+
+/// \brief Base class for opaque kernel-specific state. For example, if there
+/// is some kind of initialization required.
+struct ARROW_EXPORT KernelState {
+  virtual ~KernelState() = default;
+};
+
+/// \brief Context/state for the execution of a particular kernel.
+class ARROW_EXPORT KernelContext {
+ public:
+  // Can pass optional backreference; not used consistently for the
+  // moment but will be made so in the future
+  explicit KernelContext(ExecContext* exec_ctx, const Kernel* kernel = NULLPTR)
+      : exec_ctx_(exec_ctx), kernel_(kernel) {}
+
+  /// \brief Allocate buffer from the context's memory pool. The contents are
+  /// not initialized.
+  Result<std::shared_ptr<ResizableBuffer>> Allocate(int64_t nbytes);
+
+  /// \brief Allocate buffer for bitmap from the context's memory pool. Like
+  /// Allocate, the contents of the buffer are not initialized but the last
+  /// byte is preemptively zeroed to help avoid ASAN or valgrind issues.
+  Result<std::shared_ptr<ResizableBuffer>> AllocateBitmap(int64_t num_bits);
+
+  /// \brief Assign the active KernelState to be utilized for each stage of
+  /// kernel execution. Ownership and memory lifetime of the KernelState must
+  /// be minded separately.
+  void SetState(KernelState* state) { state_ = state; }
+
+  // Set kernel that is being invoked since some kernel
+  // implementations will examine the kernel state.
+  void SetKernel(const Kernel* kernel) { kernel_ = kernel; }
+
+  KernelState* state() { return state_; }
+
+  /// \brief Configuration related to function execution that is to be shared
+  /// across multiple kernels.
+  ExecContext* exec_context() { return exec_ctx_; }
+
+  /// \brief The memory pool to use for allocations. For now, it uses the
+  /// MemoryPool contained in the ExecContext used to create the KernelContext.
+  MemoryPool* memory_pool() { return exec_ctx_->memory_pool(); }
+
+  const Kernel* kernel() const { return kernel_; }
+
+ private:
+  ExecContext* exec_ctx_;
+  KernelState* state_ = NULLPTR;
+  const Kernel* kernel_ = NULLPTR;
+};
+
+/// \brief An type-checking interface to permit customizable validation rules
+/// for use with InputType and KernelSignature. This is for scenarios where the
+/// acceptance is not an exact type instance, such as a TIMESTAMP type for a
+/// specific TimeUnit, but permitting any time zone.
+struct ARROW_EXPORT TypeMatcher {
+  virtual ~TypeMatcher() = default;
+
+  /// \brief Return true if this matcher accepts the data type.
+  virtual bool Matches(const DataType& type) const = 0;
+
+  /// \brief A human-interpretable string representation of what the type
+  /// matcher checks for, usable when printing KernelSignature or formatting
+  /// error messages.
+  virtual std::string ToString() const = 0;
+
+  /// \brief Return true if this TypeMatcher contains the same matching rule as
+  /// the other. Currently depends on RTTI.
+  virtual bool Equals(const TypeMatcher& other) const = 0;
+};
+
+namespace match {
+
+/// \brief Match any DataType instance having the same DataType::id.
+ARROW_EXPORT std::shared_ptr<TypeMatcher> SameTypeId(Type::type type_id);
+
+/// \brief Match any TimestampType instance having the same unit, but the time
+/// zones can be different.
+ARROW_EXPORT std::shared_ptr<TypeMatcher> TimestampTypeUnit(TimeUnit::type unit);
+ARROW_EXPORT std::shared_ptr<TypeMatcher> Time32TypeUnit(TimeUnit::type unit);
+ARROW_EXPORT std::shared_ptr<TypeMatcher> Time64TypeUnit(TimeUnit::type unit);
+ARROW_EXPORT std::shared_ptr<TypeMatcher> DurationTypeUnit(TimeUnit::type unit);
+
+// \brief Match any integer type
+ARROW_EXPORT std::shared_ptr<TypeMatcher> Integer();
+
+// Match types using 32-bit varbinary representation
+ARROW_EXPORT std::shared_ptr<TypeMatcher> BinaryLike();
+
+// Match types using 64-bit varbinary representation
+ARROW_EXPORT std::shared_ptr<TypeMatcher> LargeBinaryLike();
+
+// Match any fixed binary type
+ARROW_EXPORT std::shared_ptr<TypeMatcher> FixedSizeBinaryLike();
+
+// \brief Match any primitive type (boolean or any type representable as a C
+// Type)
+ARROW_EXPORT std::shared_ptr<TypeMatcher> Primitive();
+
+// \brief Match any integer type that can be used as run-end in run-end encoded
+// arrays
+ARROW_EXPORT std::shared_ptr<TypeMatcher> RunEndInteger();
+
+/// \brief Match run-end encoded types that use any valid run-end type and
+/// encode specific value types
+///
+/// @param[in] value_type_matcher a matcher that is applied to the values field
+ARROW_EXPORT std::shared_ptr<TypeMatcher> RunEndEncoded(
+    std::shared_ptr<TypeMatcher> value_type_matcher);
+
+/// \brief Match run-end encoded types that use any valid run-end type and
+/// encode specific value types
+///
+/// @param[in] value_type_id a type id that the type of the values field should match
+ARROW_EXPORT std::shared_ptr<TypeMatcher> RunEndEncoded(Type::type value_type_id);
+
+/// \brief Match run-end encoded types that encode specific run-end and value types
+///
+/// @param[in] run_end_type_matcher a matcher that is applied to the run_ends field
+/// @param[in] value_type_matcher a matcher that is applied to the values field
+ARROW_EXPORT std::shared_ptr<TypeMatcher> RunEndEncoded(
+    std::shared_ptr<TypeMatcher> run_end_type_matcher,
+    std::shared_ptr<TypeMatcher> value_type_matcher);
+
+}  // namespace match
+
+/// \brief An object used for type-checking arguments to be passed to a kernel
+/// and stored in a KernelSignature. The type-checking rule can be supplied
+/// either with an exact DataType instance or a custom TypeMatcher.
+class ARROW_EXPORT InputType {
+ public:
+  /// \brief The kind of type-checking rule that the InputType contains.
+  enum Kind {
+    /// \brief Accept any value type.
+    ANY_TYPE,
+
+    /// \brief A fixed arrow::DataType and will only exact match having this
+    /// exact type (e.g. same TimestampType unit, same decimal scale and
+    /// precision, or same nested child types).
+    EXACT_TYPE,
+
+    /// \brief Uses a TypeMatcher implementation to check the type.
+    USE_TYPE_MATCHER
+  };
+
+  /// \brief Accept any value type
+  InputType() : kind_(ANY_TYPE) {}
+
+  /// \brief Accept an exact value type.
+  InputType(std::shared_ptr<DataType> type)  // NOLINT implicit construction
+      : kind_(EXACT_TYPE), type_(std::move(type)) {}
+
+  /// \brief Use the passed TypeMatcher to type check.
+  InputType(std::shared_ptr<TypeMatcher> type_matcher)  // NOLINT implicit construction
+      : kind_(USE_TYPE_MATCHER), type_matcher_(std::move(type_matcher)) {}
+
+  /// \brief Match any type with the given Type::type. Uses a TypeMatcher for
+  /// its implementation.
+  InputType(Type::type type_id)  // NOLINT implicit construction
+      : InputType(match::SameTypeId(type_id)) {}
+
+  InputType(const InputType& other) { CopyInto(other); }
+
+  void operator=(const InputType& other) { CopyInto(other); }
+
+  InputType(InputType&& other) { MoveInto(std::forward<InputType>(other)); }
+
+  void operator=(InputType&& other) { MoveInto(std::forward<InputType>(other)); }
+
+  // \brief Match any input (array, scalar of any type)
+  static InputType Any() { return InputType(); }
+
+  /// \brief Return true if this input type matches the same type cases as the
+  /// other.
+  bool Equals(const InputType& other) const;
+
+  bool operator==(const InputType& other) const { return this->Equals(other); }
+
+  bool operator!=(const InputType& other) const { return !(*this == other); }
+
+  /// \brief Return hash code.
+  size_t Hash() const;
+
+  /// \brief Render a human-readable string representation.
+  std::string ToString() const;
+
+  /// \brief Return true if the Datum matches this argument kind in
+  /// type (and only allows scalar or array-like Datums).
+  bool Matches(const Datum& value) const;
+
+  /// \brief Return true if the type matches this InputType
+  bool Matches(const DataType& type) const;
+
+  /// \brief The type matching rule that this InputType uses.
+  Kind kind() const { return kind_; }
+
+  /// \brief For InputType::EXACT_TYPE kind, the exact type that this InputType
+  /// must match. Otherwise this function should not be used and will assert in
+  /// debug builds.
+  const std::shared_ptr<DataType>& type() const;
+
+  /// \brief For InputType::USE_TYPE_MATCHER, the TypeMatcher to be used for
+  /// checking the type of a value. Otherwise this function should not be used
+  /// and will assert in debug builds.
+  const TypeMatcher& type_matcher() const;
+
+ private:
+  void CopyInto(const InputType& other) {
+    this->kind_ = other.kind_;
+    this->type_ = other.type_;
+    this->type_matcher_ = other.type_matcher_;
+  }
+
+  void MoveInto(InputType&& other) {
+    this->kind_ = other.kind_;
+    this->type_ = std::move(other.type_);
+    this->type_matcher_ = std::move(other.type_matcher_);
+  }
+
+  Kind kind_;
+
+  // For EXACT_TYPE Kind
+  std::shared_ptr<DataType> type_;
+
+  // For USE_TYPE_MATCHER Kind
+  std::shared_ptr<TypeMatcher> type_matcher_;
+};
+
+/// \brief Container to capture both exact and input-dependent output types.
+class ARROW_EXPORT OutputType {
+ public:
+  /// \brief An enum indicating whether the value type is an invariant fixed
+  /// value or one that's computed by a kernel-defined resolver function.
+  enum ResolveKind { FIXED, COMPUTED };
+
+  /// Type resolution function. Given input types, return output type.  This
+  /// function MAY may use the kernel state to decide the output type based on
+  /// the FunctionOptions.
+  ///
+  /// This function SHOULD _not_ be used to check for arity, that is to be
+  /// performed one or more layers above.
+  using Resolver =
+      std::function<Result<TypeHolder>(KernelContext*, const std::vector<TypeHolder>&)>;
+
+  /// \brief Output an exact type
+  OutputType(std::shared_ptr<DataType> type)  // NOLINT implicit construction
+      : kind_(FIXED), type_(std::move(type)) {}
+
+  /// \brief Output a computed type depending on actual input types
+  template <typename Fn>
+  OutputType(Fn resolver)  // NOLINT implicit construction
+      : kind_(COMPUTED), resolver_(std::move(resolver)) {}
+
+  OutputType(const OutputType& other) {
+    this->kind_ = other.kind_;
+    this->type_ = other.type_;
+    this->resolver_ = other.resolver_;
+  }
+
+  OutputType(OutputType&& other) {
+    this->kind_ = other.kind_;
+    this->type_ = std::move(other.type_);
+    this->resolver_ = other.resolver_;
+  }
+
+  OutputType& operator=(const OutputType&) = default;
+  OutputType& operator=(OutputType&&) = default;
+
+  /// \brief Return the type of the expected output value of the kernel given
+  /// the input argument types. The resolver may make use of state information
+  /// kept in the KernelContext.
+  Result<TypeHolder> Resolve(KernelContext* ctx,
+                             const std::vector<TypeHolder>& args) const;
+
+  /// \brief The exact output value type for the FIXED kind.
+  const std::shared_ptr<DataType>& type() const;
+
+  /// \brief For use with COMPUTED resolution strategy. It may be more
+  /// convenient to invoke this with OutputType::Resolve returned from this
+  /// method.
+  const Resolver& resolver() const;
+
+  /// \brief Render a human-readable string representation.
+  std::string ToString() const;
+
+  /// \brief Return the kind of type resolution of this output type, whether
+  /// fixed/invariant or computed by a resolver.
+  ResolveKind kind() const { return kind_; }
+
+ private:
+  ResolveKind kind_;
+
+  // For FIXED resolution
+  std::shared_ptr<DataType> type_;
+
+  // For COMPUTED resolution
+  Resolver resolver_ = NULLPTR;
+};
+
+/// \brief Holds the input types and output type of the kernel.
+///
+/// VarArgs functions with minimum N arguments should pass up to N input types to be
+/// used to validate the input types of a function invocation. The first N-1 types
+/// will be matched against the first N-1 arguments, and the last type will be
+/// matched against the remaining arguments.
+class ARROW_EXPORT KernelSignature {
+ public:
+  KernelSignature(std::vector<InputType> in_types, OutputType out_type,
+                  bool is_varargs = false);
+
+  /// \brief Convenience ctor since make_shared can be awkward
+  static std::shared_ptr<KernelSignature> Make(std::vector<InputType> in_types,
+                                               OutputType out_type,
+                                               bool is_varargs = false);
+
+  /// \brief Return true if the signature if compatible with the list of input
+  /// value descriptors.
+  bool MatchesInputs(const std::vector<TypeHolder>& types) const;
+
+  /// \brief Returns true if the input types of each signature are
+  /// equal. Well-formed functions should have a deterministic output type
+  /// given input types, but currently it is the responsibility of the
+  /// developer to ensure this.
+  bool Equals(const KernelSignature& other) const;
+
+  bool operator==(const KernelSignature& other) const { return this->Equals(other); }
+
+  bool operator!=(const KernelSignature& other) const { return !(*this == other); }
+
+  /// \brief Compute a hash code for the signature
+  size_t Hash() const;
+
+  /// \brief The input types for the kernel. For VarArgs functions, this should
+  /// generally contain a single validator to use for validating all of the
+  /// function arguments.
+  const std::vector<InputType>& in_types() const { return in_types_; }
+
+  /// \brief The output type for the kernel. Use Resolve to return the
+  /// exact output given input argument types, since many kernels'
+  /// output types depend on their input types (or their type
+  /// metadata).
+  const OutputType& out_type() const { return out_type_; }
+
+  /// \brief Render a human-readable string representation
+  std::string ToString() const;
+
+  bool is_varargs() const { return is_varargs_; }
+
+ private:
+  std::vector<InputType> in_types_;
+  OutputType out_type_;
+  bool is_varargs_;
+
+  // For caching the hash code after it's computed the first time
+  mutable uint64_t hash_code_;
+};
+
+/// \brief A function may contain multiple variants of a kernel for a given
+/// type combination for different SIMD levels. Based on the active system's
+/// CPU info or the user's preferences, we can elect to use one over the other.
+struct SimdLevel {
+  enum type { NONE = 0, SSE4_2, AVX, AVX2, AVX512, NEON, MAX };
+};
+
+/// \brief The strategy to use for propagating or otherwise populating the
+/// validity bitmap of a kernel output.
+struct NullHandling {
+  enum type {
+    /// Compute the output validity bitmap by intersecting the validity bitmaps
+    /// of the arguments using bitwise-and operations. This means that values
+    /// in the output are valid/non-null only if the corresponding values in
+    /// all input arguments were valid/non-null. Kernel generally need not
+    /// touch the bitmap thereafter, but a kernel's exec function is permitted
+    /// to alter the bitmap after the null intersection is computed if it needs
+    /// to.
+    INTERSECTION,
+
+    /// Kernel expects a pre-allocated buffer to write the result bitmap
+    /// into. The preallocated memory is not zeroed (except for the last byte),
+    /// so the kernel should ensure to completely populate the bitmap.
+    COMPUTED_PREALLOCATE,
+
+    /// Kernel allocates and sets the validity bitmap of the output.
+    COMPUTED_NO_PREALLOCATE,
+
+    /// Kernel output is never null and a validity bitmap does not need to be
+    /// allocated.
+    OUTPUT_NOT_NULL
+  };
+};
+
+/// \brief The preference for memory preallocation of fixed-width type outputs
+/// in kernel execution.
+struct MemAllocation {
+  enum type {
+    // For data types that support pre-allocation (i.e. fixed-width), the
+    // kernel expects to be provided a pre-allocated data buffer to write
+    // into. Non-fixed-width types must always allocate their own data
+    // buffers. The allocation made for the same length as the execution batch,
+    // so vector kernels yielding differently sized output should not use this.
+    //
+    // It is valid for the data to not be preallocated but the validity bitmap
+    // is (or is computed using the intersection/bitwise-and method).
+    //
+    // For variable-size output types like BinaryType or StringType, or for
+    // nested types, this option has no effect.
+    PREALLOCATE,
+
+    // The kernel is responsible for allocating its own data buffer for
+    // fixed-width type outputs.
+    NO_PREALLOCATE
+  };
+};
+
+struct Kernel;
+
+/// \brief Arguments to pass to an KernelInit function. A struct is used to help
+/// avoid API breakage should the arguments passed need to be expanded.
+struct KernelInitArgs {
+  /// \brief A pointer to the kernel being initialized. The init function may
+  /// depend on the kernel's KernelSignature or other data contained there.
+  const Kernel* kernel;
+
+  /// \brief The types of the input arguments that the kernel is
+  /// about to be executed against.
+  const std::vector<TypeHolder>& inputs;
+
+  /// \brief Opaque options specific to this kernel. May be nullptr for functions
+  /// that do not require options.
+  const FunctionOptions* options;
+};
+
+/// \brief Common initializer function for all kernel types.
+using KernelInit = std::function<Result<std::unique_ptr<KernelState>>(
+    KernelContext*, const KernelInitArgs&)>;
+
+/// \brief Base type for kernels. Contains the function signature and
+/// optionally the state initialization function, along with some common
+/// attributes
+struct ARROW_EXPORT Kernel {
+  Kernel() = default;
+
+  Kernel(std::shared_ptr<KernelSignature> sig, KernelInit init)
+      : signature(std::move(sig)), init(std::move(init)) {}
+
+  Kernel(std::vector<InputType> in_types, OutputType out_type, KernelInit init)
+      : Kernel(KernelSignature::Make(std::move(in_types), std::move(out_type)),
+               std::move(init)) {}
+
+  /// \brief The "signature" of the kernel containing the InputType input
+  /// argument validators and OutputType output type resolver.
+  std::shared_ptr<KernelSignature> signature;
+
+  /// \brief Create a new KernelState for invocations of this kernel, e.g. to
+  /// set up any options or state relevant for execution.
+  KernelInit init;
+
+  /// \brief Create a vector of new KernelState for invocations of this kernel.
+  static Status InitAll(KernelContext*, const KernelInitArgs&,
+                        std::vector<std::unique_ptr<KernelState>>*);
+
+  /// \brief Indicates whether execution can benefit from parallelization
+  /// (splitting large chunks into smaller chunks and using multiple
+  /// threads). Some kernels may not support parallel execution at
+  /// all. Synchronization and concurrency-related issues are currently the
+  /// responsibility of the Kernel's implementation.
+  bool parallelizable = true;
+
+  /// \brief Indicates the level of SIMD instruction support in the host CPU is
+  /// required to use the function. The intention is for functions to be able to
+  /// contain multiple kernels with the same signature but different levels of SIMD,
+  /// so that the most optimized kernel supported on a host's processor can be chosen.
+  SimdLevel::type simd_level = SimdLevel::NONE;
+
+  // Additional kernel-specific data
+  std::shared_ptr<KernelState> data;
+};
+
+/// \brief The scalar kernel execution API that must be implemented for SCALAR
+/// kernel types. This includes both stateless and stateful kernels. Kernels
+/// depending on some execution state access that state via subclasses of
+/// KernelState set on the KernelContext object. Implementations should
+/// endeavor to write into pre-allocated memory if they are able, though for
+/// some kernels (e.g. in cases when a builder like StringBuilder) must be
+/// employed this may not be possible.
+using ArrayKernelExec = Status (*)(KernelContext*, const ExecSpan&, ExecResult*);
+
+/// \brief Kernel data structure for implementations of ScalarFunction. In
+/// addition to the members found in Kernel, contains the null handling
+/// and memory pre-allocation preferences.
+struct ARROW_EXPORT ScalarKernel : public Kernel {
+  ScalarKernel() = default;
+
+  ScalarKernel(std::shared_ptr<KernelSignature> sig, ArrayKernelExec exec,
+               KernelInit init = NULLPTR)
+      : Kernel(std::move(sig), init), exec(exec) {}
+
+  ScalarKernel(std::vector<InputType> in_types, OutputType out_type, ArrayKernelExec exec,
+               KernelInit init = NULLPTR)
+      : Kernel(std::move(in_types), std::move(out_type), std::move(init)), exec(exec) {}
+
+  /// \brief Perform a single invocation of this kernel. Depending on the
+  /// implementation, it may only write into preallocated memory, while in some
+  /// cases it will allocate its own memory. Any required state is managed
+  /// through the KernelContext.
+  ArrayKernelExec exec;
+
+  /// \brief Writing execution results into larger contiguous allocations
+  /// requires that the kernel be able to write into sliced output ArrayData*,
+  /// including sliced output validity bitmaps. Some kernel implementations may
+  /// not be able to do this, so setting this to false disables this
+  /// functionality.
+  bool can_write_into_slices = true;
+
+  // For scalar functions preallocated data and intersecting arg validity
+  // bitmaps is a reasonable default
+  NullHandling::type null_handling = NullHandling::INTERSECTION;
+  MemAllocation::type mem_allocation = MemAllocation::PREALLOCATE;
+};
+
+// ----------------------------------------------------------------------
+// VectorKernel (for VectorFunction)
+
+/// \brief Kernel data structure for implementations of VectorFunction. In
+/// contains an optional finalizer function, the null handling and memory
+/// pre-allocation preferences (which have different defaults from
+/// ScalarKernel), and some other execution-related options.
+struct ARROW_EXPORT VectorKernel : public Kernel {
+  /// \brief See VectorKernel::finalize member for usage
+  using FinalizeFunc = std::function<Status(KernelContext*, std::vector<Datum>*)>;
+
+  /// \brief Function for executing a stateful VectorKernel against a
+  /// ChunkedArray input. Does not need to be defined for all VectorKernels
+  using ChunkedExec = Status (*)(KernelContext*, const ExecBatch&, Datum* out);
+
+  VectorKernel() = default;
+
+  VectorKernel(std::vector<InputType> in_types, OutputType out_type, ArrayKernelExec exec,
+               KernelInit init = NULLPTR, FinalizeFunc finalize = NULLPTR)
+      : Kernel(std::move(in_types), std::move(out_type), std::move(init)),
+        exec(exec),
+        finalize(std::move(finalize)) {}
+
+  VectorKernel(std::shared_ptr<KernelSignature> sig, ArrayKernelExec exec,
+               KernelInit init = NULLPTR, FinalizeFunc finalize = NULLPTR)
+      : Kernel(std::move(sig), std::move(init)),
+        exec(exec),
+        finalize(std::move(finalize)) {}
+
+  /// \brief Perform a single invocation of this kernel. Any required state is
+  /// managed through the KernelContext.
+  ArrayKernelExec exec;
+
+  /// \brief Execute the kernel on a ChunkedArray. Does not need to be defined
+  ChunkedExec exec_chunked = NULLPTR;
+
+  /// \brief For VectorKernel, convert intermediate results into finalized
+  /// results. Mutates input argument. Some kernels may accumulate state
+  /// (example: hashing-related functions) through processing chunked inputs, and
+  /// then need to attach some accumulated state to each of the outputs of
+  /// processing each chunk of data.
+  FinalizeFunc finalize;
+
+  /// Since vector kernels generally are implemented rather differently from
+  /// scalar/elementwise kernels (and they may not even yield arrays of the same
+  /// size), so we make the developer opt-in to any memory preallocation rather
+  /// than having to turn it off.
+  NullHandling::type null_handling = NullHandling::COMPUTED_NO_PREALLOCATE;
+  MemAllocation::type mem_allocation = MemAllocation::NO_PREALLOCATE;
+
+  /// \brief Writing execution results into larger contiguous allocations
+  /// requires that the kernel be able to write into sliced output ArrayData*,
+  /// including sliced output validity bitmaps. Some kernel implementations may
+  /// not be able to do this, so setting this to false disables this
+  /// functionality.
+  bool can_write_into_slices = true;
+
+  /// Some vector kernels can do chunkwise execution using ExecSpanIterator,
+  /// in some cases accumulating some state. Other kernels (like Take) need to
+  /// be passed whole arrays and don't work on ChunkedArray inputs
+  bool can_execute_chunkwise = true;
+
+  /// Some kernels (like unique and value_counts) yield non-chunked output from
+  /// chunked-array inputs. This option controls how the results are boxed when
+  /// returned from ExecVectorFunction
+  ///
+  /// true -> ChunkedArray
+  /// false -> Array
+  bool output_chunked = true;
+};
+
+// ----------------------------------------------------------------------
+// ScalarAggregateKernel (for ScalarAggregateFunction)
+
+using ScalarAggregateConsume = Status (*)(KernelContext*, const ExecSpan&);
+using ScalarAggregateMerge = Status (*)(KernelContext*, KernelState&&, KernelState*);
+// Finalize returns Datum to permit multiple return values
+using ScalarAggregateFinalize = Status (*)(KernelContext*, Datum*);
+
+/// \brief Kernel data structure for implementations of
+/// ScalarAggregateFunction. The four necessary components of an aggregation
+/// kernel are the init, consume, merge, and finalize functions.
+///
+/// * init: creates a new KernelState for a kernel.
+/// * consume: processes an ExecSpan and updates the KernelState found in the
+///   KernelContext.
+/// * merge: combines one KernelState with another.
+/// * finalize: produces the end result of the aggregation using the
+///   KernelState in the KernelContext.
+struct ARROW_EXPORT ScalarAggregateKernel : public Kernel {
+  ScalarAggregateKernel(std::shared_ptr<KernelSignature> sig, KernelInit init,
+                        ScalarAggregateConsume consume, ScalarAggregateMerge merge,
+                        ScalarAggregateFinalize finalize, const bool ordered)
+      : Kernel(std::move(sig), std::move(init)),
+        consume(consume),
+        merge(merge),
+        finalize(finalize),
+        ordered(ordered) {}
+
+  ScalarAggregateKernel(std::vector<InputType> in_types, OutputType out_type,
+                        KernelInit init, ScalarAggregateConsume consume,
+                        ScalarAggregateMerge merge, ScalarAggregateFinalize finalize,
+                        const bool ordered)
+      : ScalarAggregateKernel(
+            KernelSignature::Make(std::move(in_types), std::move(out_type)),
+            std::move(init), consume, merge, finalize, ordered) {}
+
+  /// \brief Merge a vector of KernelStates into a single KernelState.
+  /// The merged state will be returned and will be set on the KernelContext.
+  static Result<std::unique_ptr<KernelState>> MergeAll(
+      const ScalarAggregateKernel* kernel, KernelContext* ctx,
+      std::vector<std::unique_ptr<KernelState>> states);
+
+  ScalarAggregateConsume consume;
+  ScalarAggregateMerge merge;
+  ScalarAggregateFinalize finalize;
+  /// \brief Whether this kernel requires ordering
+  /// Some aggregations, such as, "first", requires some kind of input order. The
+  /// order can be implicit, e.g., the order of the input data, or explicit, e.g.
+  /// the ordering specified with a window aggregation.
+  /// The caller of the aggregate kernel is responsible for passing data in some
+  /// defined order to the kernel. The flag here is a way for the kernel to tell
+  /// the caller that data passed to the kernel must be defined in some order.
+  bool ordered = false;
+};
+
+// ----------------------------------------------------------------------
+// HashAggregateKernel (for HashAggregateFunction)
+
+using HashAggregateResize = Status (*)(KernelContext*, int64_t);
+using HashAggregateConsume = Status (*)(KernelContext*, const ExecSpan&);
+using HashAggregateMerge = Status (*)(KernelContext*, KernelState&&, const ArrayData&);
+
+// Finalize returns Datum to permit multiple return values
+using HashAggregateFinalize = Status (*)(KernelContext*, Datum*);
+
+/// \brief Kernel data structure for implementations of
+/// HashAggregateFunction. The four necessary components of an aggregation
+/// kernel are the init, consume, merge, and finalize functions.
+///
+/// * init: creates a new KernelState for a kernel.
+/// * resize: ensure that the KernelState can accommodate the specified number of groups.
+/// * consume: processes an ExecSpan (which includes the argument as well
+///   as an array of group identifiers) and updates the KernelState found in the
+///   KernelContext.
+/// * merge: combines one KernelState with another.
+/// * finalize: produces the end result of the aggregation using the
+///   KernelState in the KernelContext.
+struct ARROW_EXPORT HashAggregateKernel : public Kernel {
+  HashAggregateKernel() = default;
+
+  HashAggregateKernel(std::shared_ptr<KernelSignature> sig, KernelInit init,
+                      HashAggregateResize resize, HashAggregateConsume consume,
+                      HashAggregateMerge merge, HashAggregateFinalize finalize,
+                      const bool ordered)
+      : Kernel(std::move(sig), std::move(init)),
+        resize(resize),
+        consume(consume),
+        merge(merge),
+        finalize(finalize),
+        ordered(ordered) {}
+
+  HashAggregateKernel(std::vector<InputType> in_types, OutputType out_type,
+                      KernelInit init, HashAggregateConsume consume,
+                      HashAggregateResize resize, HashAggregateMerge merge,
+                      HashAggregateFinalize finalize, const bool ordered)
+      : HashAggregateKernel(
+            KernelSignature::Make(std::move(in_types), std::move(out_type)),
+            std::move(init), resize, consume, merge, finalize, ordered) {}
+
+  HashAggregateResize resize;
+  HashAggregateConsume consume;
+  HashAggregateMerge merge;
+  HashAggregateFinalize finalize;
+  /// @brief whether the summarizer requires ordering
+  /// This is similar to ScalarAggregateKernel. See ScalarAggregateKernel
+  /// for detailed doc of this variable.
+  bool ordered = false;
+};
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/compute/type_fwd.h

@@ -0,0 +1,58 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+
+struct Datum;
+struct TypeHolder;
+
+namespace compute {
+
+class Function;
+class ScalarAggregateFunction;
+class FunctionExecutor;
+class FunctionOptions;
+class FunctionRegistry;
+
+/// \brief Return the process-global function registry.
+// Defined in registry.cc
+ARROW_EXPORT FunctionRegistry* GetFunctionRegistry();
+
+class CastOptions;
+
+struct ExecBatch;
+class ExecContext;
+class KernelContext;
+
+struct Kernel;
+struct ScalarKernel;
+struct ScalarAggregateKernel;
+struct VectorKernel;
+
+struct KernelState;
+
+class Expression;
+
+ARROW_EXPORT ExecContext* default_exec_context();
+ARROW_EXPORT ExecContext* threaded_exec_context();
+
+}  // namespace compute
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/algorithm.h

@@ -0,0 +1,33 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include "arrow/result.h"
+
+namespace arrow {
+
+template <typename InputIterator, typename OutputIterator, typename UnaryOperation>
+Status MaybeTransform(InputIterator first, InputIterator last, OutputIterator out,
+                      UnaryOperation unary_op) {
+  for (; first != last; ++first, (void)++out) {
+    ARROW_ASSIGN_OR_RAISE(*out, unary_op(*first));
+  }
+  return Status::OK();
+}
+
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/align_util.h

@@ -0,0 +1,221 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <algorithm>
+
+#include "arrow/memory_pool.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/bit_util.h"
+
+namespace arrow {
+namespace internal {
+
+struct BitmapWordAlignParams {
+  int64_t leading_bits;
+  int64_t trailing_bits;
+  int64_t trailing_bit_offset;
+  const uint8_t* aligned_start;
+  int64_t aligned_bits;
+  int64_t aligned_words;
+};
+
+// Compute parameters for accessing a bitmap using aligned word instructions.
+// The returned parameters describe:
+// - a leading area of size `leading_bits` before the aligned words
+// - a word-aligned area of size `aligned_bits`
+// - a trailing area of size `trailing_bits` after the aligned words
+template <uint64_t ALIGN_IN_BYTES>
+inline BitmapWordAlignParams BitmapWordAlign(const uint8_t* data, int64_t bit_offset,
+                                             int64_t length) {
+  static_assert(bit_util::IsPowerOf2(ALIGN_IN_BYTES),
+                "ALIGN_IN_BYTES should be a positive power of two");
+  constexpr uint64_t ALIGN_IN_BITS = ALIGN_IN_BYTES * 8;
+
+  BitmapWordAlignParams p;
+
+  // Compute a "bit address" that we can align up to ALIGN_IN_BITS.
+  // We don't care about losing the upper bits since we are only interested in the
+  // difference between both addresses.
+  const uint64_t bit_addr =
+      reinterpret_cast<size_t>(data) * 8 + static_cast<uint64_t>(bit_offset);
+  const uint64_t aligned_bit_addr = bit_util::RoundUpToPowerOf2(bit_addr, ALIGN_IN_BITS);
+
+  p.leading_bits = std::min<int64_t>(length, aligned_bit_addr - bit_addr);
+  p.aligned_words = (length - p.leading_bits) / ALIGN_IN_BITS;
+  p.aligned_bits = p.aligned_words * ALIGN_IN_BITS;
+  p.trailing_bits = length - p.leading_bits - p.aligned_bits;
+  p.trailing_bit_offset = bit_offset + p.leading_bits + p.aligned_bits;
+
+  p.aligned_start = data + (bit_offset + p.leading_bits) / 8;
+  return p;
+}
+}  // namespace internal
+
+namespace util {
+
+// Functions to check if the provided Arrow object is aligned by the specified alignment
+
+/// \brief Special alignment value to use data type-specific alignment
+///
+/// If this is passed as the `alignment` in one of the CheckAlignment or EnsureAlignment
+/// functions, then the function will ensure each buffer is suitably aligned
+/// for the data type of the array.  For example, given an int32 buffer the values
+/// buffer's address must be a multiple of 4.  Given a large_string buffer the offsets
+/// buffer's address must be a multiple of 8.
+constexpr int64_t kValueAlignment = -3;
+
+/// \brief Calculate if the buffer's address is a multiple of `alignment`
+///
+/// If `alignment` is less than or equal to 0 then this method will always return true
+/// \param buffer the buffer to check
+/// \param alignment the alignment (in bytes) to check for
+ARROW_EXPORT bool CheckAlignment(const Buffer& buffer, int64_t alignment);
+/// \brief Calculate if all buffers in the array data are aligned
+///
+/// This will also check the buffers in the dictionary and any children
+/// \param array the array data to check
+/// \param alignment the alignment (in bytes) to check for
+ARROW_EXPORT bool CheckAlignment(const ArrayData& array, int64_t alignment);
+/// \brief Calculate if all buffers in the array are aligned
+///
+/// This will also check the buffers in the dictionary and any children
+/// \param array the array to check
+/// \param alignment the alignment (in bytes) to check for
+ARROW_EXPORT bool CheckAlignment(const Array& array, int64_t alignment);
+
+// Following functions require an additional boolean vector which stores the
+// alignment check bits of the constituent objects.
+// For example, needs_alignment vector for a ChunkedArray will contain the
+// check bits of the constituent Arrays.
+// The boolean vector check was introduced to minimize the repetitive checks
+// of the constituent objects during the EnsureAlignment function where certain
+// objects can be ignored for further checking if we already know that they are
+// completely aligned.
+
+/// \brief Calculate which (if any) chunks in a chunked array are unaligned
+/// \param array the array to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param needs_alignment an output vector that will store the results of the check
+///        it must be set to a valid vector.  Extra elements will be added to the end
+///        of the vector for each chunk that is checked.  `true` will be stored if
+///        the chunk is unaligned.
+/// \param offset the index of the chunk to start checking
+/// \return true if all chunks (starting at `offset`) are aligned, false otherwise
+ARROW_EXPORT bool CheckAlignment(const ChunkedArray& array, int64_t alignment,
+                                 std::vector<bool>* needs_alignment, int offset = 0);
+
+/// \brief calculate which (if any) columns in a record batch are unaligned
+/// \param batch the batch to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param needs_alignment an output vector that will store the results of the
+///        check.  It must be set to a valid vector.  Extra elements will be added
+///        to the end of the vector for each column that is checked.  `true` will be
+///        stored if the column is unaligned.
+ARROW_EXPORT bool CheckAlignment(const RecordBatch& batch, int64_t alignment,
+                                 std::vector<bool>* needs_alignment);
+
+/// \brief calculate which (if any) columns in a table are unaligned
+/// \param table the table to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param needs_alignment an output vector that will store the results of the
+///        check.  It must be set to a valid vector.  Extra elements will be added
+///        to the end of the vector for each column that is checked.  `true` will be
+///        stored if the column is unaligned.
+ARROW_EXPORT bool CheckAlignment(const Table& table, int64_t alignment,
+                                 std::vector<bool>* needs_alignment);
+
+/// \brief return a buffer that has the given alignment and the same data as the input
+/// buffer
+///
+/// If the input buffer is already aligned then this method will return the input buffer
+/// If the input buffer is not already aligned then this method will allocate a new
+/// buffer.  The alignment of the new buffer will have at least
+/// max(kDefaultBufferAlignment, alignment) bytes of alignment.
+///
+/// \param buffer the buffer to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate a new buffer if the
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<Buffer>> EnsureAlignment(
+    std::shared_ptr<Buffer> buffer, int64_t alignment, MemoryPool* memory_pool);
+
+/// \brief return an array data where all buffers are aligned by the given alignment
+///
+/// If any input buffer is already aligned then this method will reuse that same input
+/// buffer.
+///
+/// \param array_data the array data to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate new buffers if any
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<ArrayData>> EnsureAlignment(
+    std::shared_ptr<ArrayData> array_data, int64_t alignment, MemoryPool* memory_pool);
+
+/// \brief return an array where all buffers are aligned by the given alignment
+///
+/// If any input buffer is already aligned then this method will reuse that same input
+/// buffer.
+///
+/// \param array the array to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate new buffers if any
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<Array>> EnsureAlignment(std::shared_ptr<Array> array,
+                                                            int64_t alignment,
+                                                            MemoryPool* memory_pool);
+
+/// \brief return a chunked array where all buffers are aligned by the given alignment
+///
+/// If any input buffer is already aligned then this method will reuse that same input
+/// buffer.
+///
+/// \param array the chunked array to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate new buffers if any
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<ChunkedArray>> EnsureAlignment(
+    std::shared_ptr<ChunkedArray> array, int64_t alignment, MemoryPool* memory_pool);
+
+/// \brief return a record batch where all buffers are aligned by the given alignment
+///
+/// If any input buffer is already aligned then this method will reuse that same input
+/// buffer.
+///
+/// \param batch the batch to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate new buffers if any
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<RecordBatch>> EnsureAlignment(
+    std::shared_ptr<RecordBatch> batch, int64_t alignment, MemoryPool* memory_pool);
+
+/// \brief return a table where all buffers are aligned by the given alignment
+///
+/// If any input buffer is already aligned then this method will reuse that same input
+/// buffer.
+///
+/// \param table the table to check
+/// \param alignment the alignment (in bytes) to check for
+/// \param memory_pool a memory pool that will be used to allocate new buffers if any
+///        input buffer is not sufficiently aligned
+ARROW_EXPORT Result<std::shared_ptr<Table>> EnsureAlignment(std::shared_ptr<Table> table,
+                                                            int64_t alignment,
+                                                            MemoryPool* memory_pool);
+
+}  // namespace util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/aligned_storage.h

@@ -0,0 +1,145 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstring>
+#include <type_traits>
+#include <utility>
+
+#include "arrow/util/launder.h"
+#include "arrow/util/macros.h"
+
+namespace arrow {
+namespace internal {
+
+template <typename T>
+class AlignedStorage {
+ public:
+  static constexpr bool can_memcpy = std::is_trivial<T>::value;
+
+  constexpr T* get() noexcept {
+    return arrow::internal::launder(reinterpret_cast<T*>(&data_));
+  }
+
+  constexpr const T* get() const noexcept {
+    // Use fully qualified name to avoid ambiguities with MSVC (ARROW-14800)
+    return arrow::internal::launder(reinterpret_cast<const T*>(&data_));
+  }
+
+  void destroy() noexcept {
+    if (!std::is_trivially_destructible<T>::value) {
+      get()->~T();
+    }
+  }
+
+  template <typename... A>
+  void construct(A&&... args) noexcept {
+    new (&data_) T(std::forward<A>(args)...);
+  }
+
+  template <typename V>
+  void assign(V&& v) noexcept {
+    *get() = std::forward<V>(v);
+  }
+
+  void move_construct(AlignedStorage* other) noexcept {
+    new (&data_) T(std::move(*other->get()));
+  }
+
+  void move_assign(AlignedStorage* other) noexcept { *get() = std::move(*other->get()); }
+
+  template <bool CanMemcpy = can_memcpy>
+  static typename std::enable_if<CanMemcpy>::type move_construct_several(
+      AlignedStorage* ARROW_RESTRICT src, AlignedStorage* ARROW_RESTRICT dest, size_t n,
+      size_t memcpy_length) noexcept {
+    memcpy(dest->get(), src->get(), memcpy_length * sizeof(T));
+  }
+
+  template <bool CanMemcpy = can_memcpy>
+  static typename std::enable_if<CanMemcpy>::type
+  move_construct_several_and_destroy_source(AlignedStorage* ARROW_RESTRICT src,
+                                            AlignedStorage* ARROW_RESTRICT dest, size_t n,
+                                            size_t memcpy_length) noexcept {
+    memcpy(dest->get(), src->get(), memcpy_length * sizeof(T));
+  }
+
+  template <bool CanMemcpy = can_memcpy>
+  static typename std::enable_if<!CanMemcpy>::type move_construct_several(
+      AlignedStorage* ARROW_RESTRICT src, AlignedStorage* ARROW_RESTRICT dest, size_t n,
+      size_t memcpy_length) noexcept {
+    for (size_t i = 0; i < n; ++i) {
+      new (dest[i].get()) T(std::move(*src[i].get()));
+    }
+  }
+
+  template <bool CanMemcpy = can_memcpy>
+  static typename std::enable_if<!CanMemcpy>::type
+  move_construct_several_and_destroy_source(AlignedStorage* ARROW_RESTRICT src,
+                                            AlignedStorage* ARROW_RESTRICT dest, size_t n,
+                                            size_t memcpy_length) noexcept {
+    for (size_t i = 0; i < n; ++i) {
+      new (dest[i].get()) T(std::move(*src[i].get()));
+      src[i].destroy();
+    }
+  }
+
+  static void move_construct_several(AlignedStorage* ARROW_RESTRICT src,
+                                     AlignedStorage* ARROW_RESTRICT dest,
+                                     size_t n) noexcept {
+    move_construct_several(src, dest, n, n);
+  }
+
+  static void move_construct_several_and_destroy_source(
+      AlignedStorage* ARROW_RESTRICT src, AlignedStorage* ARROW_RESTRICT dest,
+      size_t n) noexcept {
+    move_construct_several_and_destroy_source(src, dest, n, n);
+  }
+
+  static void destroy_several(AlignedStorage* p, size_t n) noexcept {
+    if (!std::is_trivially_destructible<T>::value) {
+      for (size_t i = 0; i < n; ++i) {
+        p[i].destroy();
+      }
+    }
+  }
+
+ private:
+#if !defined(__clang__) && defined(__GNUC__) && defined(__i386__)
+  // Workaround for GCC bug on i386:
+  //   alignof(int64 | float64) can give different results depending on the
+  //   compilation context, leading to internal ABI mismatch manifesting
+  //   in incorrect propagation of Result<int64 | float64> between
+  //   compilation units.
+  // (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88115)
+  static constexpr size_t alignment() {
+    if (std::is_integral_v<T> && sizeof(T) == 8) {
+      return 4;
+    } else if (std::is_floating_point_v<T> && sizeof(T) == 8) {
+      return 4;
+    }
+    return alignof(T);
+  }
+
+  typename std::aligned_storage<sizeof(T), alignment()>::type data_;
+#else
+  typename std::aligned_storage<sizeof(T), alignof(T)>::type data_;
+#endif
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/async_generator.h

@@ -0,0 +1,2058 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <atomic>
+#include <cassert>
+#include <cstring>
+#include <deque>
+#include <limits>
+#include <optional>
+#include <queue>
+
+#include "arrow/util/async_generator_fwd.h"
+#include "arrow/util/async_util.h"
+#include "arrow/util/functional.h"
+#include "arrow/util/future.h"
+#include "arrow/util/io_util.h"
+#include "arrow/util/iterator.h"
+#include "arrow/util/mutex.h"
+#include "arrow/util/queue.h"
+#include "arrow/util/thread_pool.h"
+
+namespace arrow {
+
+// The methods in this file create, modify, and utilize AsyncGenerator which is an
+// iterator of futures.  This allows an asynchronous source (like file input) to be run
+// through a pipeline in the same way that iterators can be used to create pipelined
+// workflows.
+//
+// In order to support pipeline parallelism we introduce the concept of asynchronous
+// reentrancy. This is different than synchronous reentrancy.  With synchronous code a
+// function is reentrant if the function can be called again while a previous call to that
+// function is still running.  Unless otherwise specified none of these generators are
+// synchronously reentrant.  Care should be taken to avoid calling them in such a way (and
+// the utilities Visit/Collect/Await take care to do this).
+//
+// Asynchronous reentrancy on the other hand means the function is called again before the
+// future returned by the function is marked finished (but after the call to get the
+// future returns).  Some of these generators are async-reentrant while others (e.g.
+// those that depend on ordered processing like decompression) are not.  Read the MakeXYZ
+// function comments to determine which generators support async reentrancy.
+//
+// Note: Generators that are not asynchronously reentrant can still support readahead
+// (\see MakeSerialReadaheadGenerator).
+//
+// Readahead operators, and some other operators, may introduce queueing.  Any operators
+// that introduce buffering should detail the amount of buffering they introduce in their
+// MakeXYZ function comments.
+//
+// A generator should always be fully consumed before it is destroyed.
+// A generator should not mark a future complete with an error status or a terminal value
+//   until all outstanding futures have completed.  Generators that spawn multiple
+//   concurrent futures may need to hold onto an error while other concurrent futures wrap
+//   up.
+template <typename T>
+struct IterationTraits<AsyncGenerator<T>> {
+  /// \brief by default when iterating through a sequence of AsyncGenerator<T>,
+  /// an empty function indicates the end of iteration.
+  static AsyncGenerator<T> End() { return AsyncGenerator<T>(); }
+
+  static bool IsEnd(const AsyncGenerator<T>& val) { return !val; }
+};
+
+template <typename T>
+Future<T> AsyncGeneratorEnd() {
+  return Future<T>::MakeFinished(IterationTraits<T>::End());
+}
+
+/// returning a future that completes when all have been visited
+template <typename T, typename Visitor>
+Future<> VisitAsyncGenerator(AsyncGenerator<T> generator, Visitor visitor) {
+  struct LoopBody {
+    struct Callback {
+      Result<ControlFlow<>> operator()(const T& next) {
+        if (IsIterationEnd(next)) {
+          return Break();
+        } else {
+          auto visited = visitor(next);
+          if (visited.ok()) {
+            return Continue();
+          } else {
+            return visited;
+          }
+        }
+      }
+
+      Visitor visitor;
+    };
+
+    Future<ControlFlow<>> operator()() {
+      Callback callback{visitor};
+      auto next = generator();
+      return next.Then(std::move(callback));
+    }
+
+    AsyncGenerator<T> generator;
+    Visitor visitor;
+  };
+
+  return Loop(LoopBody{std::move(generator), std::move(visitor)});
+}
+
+/// \brief Wait for an async generator to complete, discarding results.
+template <typename T>
+Future<> DiscardAllFromAsyncGenerator(AsyncGenerator<T> generator) {
+  std::function<Status(T)> visitor = [](const T&) { return Status::OK(); };
+  return VisitAsyncGenerator(generator, visitor);
+}
+
+/// \brief Collect the results of an async generator into a vector
+template <typename T>
+Future<std::vector<T>> CollectAsyncGenerator(AsyncGenerator<T> generator) {
+  auto vec = std::make_shared<std::vector<T>>();
+  auto loop_body = [generator = std::move(generator),
+                    vec = std::move(vec)]() -> Future<ControlFlow<std::vector<T>>> {
+    auto next = generator();
+    return next.Then([vec](const T& result) -> Result<ControlFlow<std::vector<T>>> {
+      if (IsIterationEnd(result)) {
+        return Break(*vec);
+      } else {
+        vec->push_back(result);
+        return Continue();
+      }
+    });
+  };
+  return Loop(std::move(loop_body));
+}
+
+/// \see MakeMappedGenerator
+template <typename T, typename V>
+class MappingGenerator {
+ public:
+  MappingGenerator(AsyncGenerator<T> source, std::function<Future<V>(const T&)> map)
+      : state_(std::make_shared<State>(std::move(source), std::move(map))) {}
+
+  Future<V> operator()() {
+    auto future = Future<V>::Make();
+    bool should_trigger;
+    {
+      auto guard = state_->mutex.Lock();
+      if (state_->finished) {
+        return AsyncGeneratorEnd<V>();
+      }
+      should_trigger = state_->waiting_jobs.empty();
+      state_->waiting_jobs.push_back(future);
+    }
+    if (should_trigger) {
+      state_->source().AddCallback(Callback{state_});
+    }
+    return future;
+  }
+
+ private:
+  struct State {
+    State(AsyncGenerator<T> source, std::function<Future<V>(const T&)> map)
+        : source(std::move(source)),
+          map(std::move(map)),
+          waiting_jobs(),
+          mutex(),
+          finished(false) {}
+
+    void Purge() {
+      // This might be called by an original callback (if the source iterator fails or
+      // ends) or by a mapped callback (if the map function fails or ends prematurely).
+      // Either way it should only be called once and after finished is set so there is no
+      // need to guard access to `waiting_jobs`.
+      while (!waiting_jobs.empty()) {
+        waiting_jobs.front().MarkFinished(IterationTraits<V>::End());
+        waiting_jobs.pop_front();
+      }
+    }
+
+    AsyncGenerator<T> source;
+    std::function<Future<V>(const T&)> map;
+    std::deque<Future<V>> waiting_jobs;
+    util::Mutex mutex;
+    bool finished;
+  };
+
+  struct Callback;
+
+  struct MappedCallback {
+    void operator()(const Result<V>& maybe_next) {
+      bool end = !maybe_next.ok() || IsIterationEnd(*maybe_next);
+      bool should_purge = false;
+      if (end) {
+        {
+          auto guard = state->mutex.Lock();
+          should_purge = !state->finished;
+          state->finished = true;
+        }
+      }
+      sink.MarkFinished(maybe_next);
+      if (should_purge) {
+        state->Purge();
+      }
+    }
+    std::shared_ptr<State> state;
+    Future<V> sink;
+  };
+
+  struct Callback {
+    void operator()(const Result<T>& maybe_next) {
+      Future<V> sink;
+      bool end = !maybe_next.ok() || IsIterationEnd(*maybe_next);
+      bool should_purge = false;
+      bool should_trigger;
+      {
+        auto guard = state->mutex.Lock();
+        // A MappedCallback may have purged or be purging the queue;
+        // we shouldn't do anything here.
+        if (state->finished) return;
+        if (end) {
+          should_purge = !state->finished;
+          state->finished = true;
+        }
+        sink = state->waiting_jobs.front();
+        state->waiting_jobs.pop_front();
+        should_trigger = !end && !state->waiting_jobs.empty();
+      }
+      if (should_purge) {
+        state->Purge();
+      }
+      if (should_trigger) {
+        state->source().AddCallback(Callback{state});
+      }
+      if (maybe_next.ok()) {
+        const T& val = maybe_next.ValueUnsafe();
+        if (IsIterationEnd(val)) {
+          sink.MarkFinished(IterationTraits<V>::End());
+        } else {
+          Future<V> mapped_fut = state->map(val);
+          mapped_fut.AddCallback(MappedCallback{std::move(state), std::move(sink)});
+        }
+      } else {
+        sink.MarkFinished(maybe_next.status());
+      }
+    }
+
+    std::shared_ptr<State> state;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// \brief Create a generator that will apply the map function to each element of
+/// source.  The map function is not called on the end token.
+///
+/// Note: This function makes a copy of `map` for each item
+/// Note: Errors returned from the `map` function will be propagated
+///
+/// If the source generator is async-reentrant then this generator will be also
+template <typename T, typename MapFn,
+          typename Mapped = detail::result_of_t<MapFn(const T&)>,
+          typename V = typename EnsureFuture<Mapped>::type::ValueType>
+AsyncGenerator<V> MakeMappedGenerator(AsyncGenerator<T> source_generator, MapFn map) {
+  auto map_callback = [map = std::move(map)](const T& val) mutable -> Future<V> {
+    return ToFuture(map(val));
+  };
+  return MappingGenerator<T, V>(std::move(source_generator), std::move(map_callback));
+}
+
+/// \brief Create a generator that will apply the map function to
+/// each element of source.  The map function is not called on the end
+/// token.  The result of the map function should be another
+/// generator; all these generators will then be flattened to produce
+/// a single stream of items.
+///
+/// Note: This function makes a copy of `map` for each item
+/// Note: Errors returned from the `map` function will be propagated
+///
+/// If the source generator is async-reentrant then this generator will be also
+template <typename T, typename MapFn,
+          typename Mapped = detail::result_of_t<MapFn(const T&)>,
+          typename V = typename EnsureFuture<Mapped>::type::ValueType>
+AsyncGenerator<T> MakeFlatMappedGenerator(AsyncGenerator<T> source_generator, MapFn map) {
+  return MakeConcatenatedGenerator(
+      MakeMappedGenerator(std::move(source_generator), std::move(map)));
+}
+
+/// \see MakeSequencingGenerator
+template <typename T, typename ComesAfter, typename IsNext>
+class SequencingGenerator {
+ public:
+  SequencingGenerator(AsyncGenerator<T> source, ComesAfter compare, IsNext is_next,
+                      T initial_value)
+      : state_(std::make_shared<State>(std::move(source), std::move(compare),
+                                       std::move(is_next), std::move(initial_value))) {}
+
+  Future<T> operator()() {
+    {
+      auto guard = state_->mutex.Lock();
+      // We can send a result immediately if the top of the queue is either an
+      // error or the next item
+      if (!state_->queue.empty() &&
+          (!state_->queue.top().ok() ||
+           state_->is_next(state_->previous_value, *state_->queue.top()))) {
+        auto result = std::move(state_->queue.top());
+        if (result.ok()) {
+          state_->previous_value = *result;
+        }
+        state_->queue.pop();
+        return Future<T>::MakeFinished(result);
+      }
+      if (state_->finished) {
+        return AsyncGeneratorEnd<T>();
+      }
+      // The next item is not in the queue so we will need to wait
+      auto new_waiting_fut = Future<T>::Make();
+      state_->waiting_future = new_waiting_fut;
+      guard.Unlock();
+      state_->source().AddCallback(Callback{state_});
+      return new_waiting_fut;
+    }
+  }
+
+ private:
+  struct WrappedComesAfter {
+    bool operator()(const Result<T>& left, const Result<T>& right) {
+      if (!left.ok() || !right.ok()) {
+        // Should never happen
+        return false;
+      }
+      return compare(*left, *right);
+    }
+    ComesAfter compare;
+  };
+
+  struct State {
+    State(AsyncGenerator<T> source, ComesAfter compare, IsNext is_next, T initial_value)
+        : source(std::move(source)),
+          is_next(std::move(is_next)),
+          previous_value(std::move(initial_value)),
+          waiting_future(),
+          queue(WrappedComesAfter{compare}),
+          finished(false),
+          mutex() {}
+
+    AsyncGenerator<T> source;
+    IsNext is_next;
+    T previous_value;
+    Future<T> waiting_future;
+    std::priority_queue<Result<T>, std::vector<Result<T>>, WrappedComesAfter> queue;
+    bool finished;
+    util::Mutex mutex;
+  };
+
+  class Callback {
+   public:
+    explicit Callback(std::shared_ptr<State> state) : state_(std::move(state)) {}
+
+    void operator()(const Result<T> result) {
+      Future<T> to_deliver;
+      bool finished;
+      {
+        auto guard = state_->mutex.Lock();
+        bool ready_to_deliver = false;
+        if (!result.ok()) {
+          // Clear any cached results
+          while (!state_->queue.empty()) {
+            state_->queue.pop();
+          }
+          ready_to_deliver = true;
+          state_->finished = true;
+        } else if (IsIterationEnd<T>(result.ValueUnsafe())) {
+          ready_to_deliver = state_->queue.empty();
+          state_->finished = true;
+        } else {
+          ready_to_deliver = state_->is_next(state_->previous_value, *result);
+        }
+
+        if (ready_to_deliver && state_->waiting_future.is_valid()) {
+          to_deliver = state_->waiting_future;
+          if (result.ok()) {
+            state_->previous_value = *result;
+          }
+        } else {
+          state_->queue.push(result);
+        }
+        // Capture state_->finished so we can access it outside the mutex
+        finished = state_->finished;
+      }
+      // Must deliver result outside of the mutex
+      if (to_deliver.is_valid()) {
+        to_deliver.MarkFinished(result);
+      } else {
+        // Otherwise, if we didn't get the next item (or a terminal item), we
+        // need to keep looking
+        if (!finished) {
+          state_->source().AddCallback(Callback{state_});
+        }
+      }
+    }
+
+   private:
+    const std::shared_ptr<State> state_;
+  };
+
+  const std::shared_ptr<State> state_;
+};
+
+/// \brief Buffer an AsyncGenerator to return values in sequence order  ComesAfter
+/// and IsNext determine the sequence order.
+///
+/// ComesAfter should be a BinaryPredicate that only returns true if a comes after b
+///
+/// IsNext should be a BinaryPredicate that returns true, given `a` and `b`, only if
+/// `b` follows immediately after `a`.  It should return true given `initial_value` and
+/// `b` if `b` is the first item in the sequence.
+///
+/// This operator will queue unboundedly while waiting for the next item.  It is intended
+/// for jittery sources that might scatter an ordered sequence.  It is NOT intended to
+/// sort.  Using it to try and sort could result in excessive RAM usage.  This generator
+/// will queue up to N blocks where N is the max "out of order"ness of the source.
+///
+/// For example, if the source is 1,6,2,5,4,3 it will queue 3 blocks because 3 is 3
+/// blocks beyond where it belongs.
+///
+/// This generator is not async-reentrant but it consists only of a simple log(n)
+/// insertion into a priority queue.
+template <typename T, typename ComesAfter, typename IsNext>
+AsyncGenerator<T> MakeSequencingGenerator(AsyncGenerator<T> source_generator,
+                                          ComesAfter compare, IsNext is_next,
+                                          T initial_value) {
+  return SequencingGenerator<T, ComesAfter, IsNext>(
+      std::move(source_generator), std::move(compare), std::move(is_next),
+      std::move(initial_value));
+}
+
+/// \see MakeTransformedGenerator
+template <typename T, typename V>
+class TransformingGenerator {
+  // The transforming generator state will be referenced as an async generator but will
+  // also be referenced via callback to various futures.  If the async generator owner
+  // moves it around we need the state to be consistent for future callbacks.
+  struct TransformingGeneratorState
+      : std::enable_shared_from_this<TransformingGeneratorState> {
+    TransformingGeneratorState(AsyncGenerator<T> generator, Transformer<T, V> transformer)
+        : generator_(std::move(generator)),
+          transformer_(std::move(transformer)),
+          last_value_(),
+          finished_() {}
+
+    Future<V> operator()() {
+      while (true) {
+        auto maybe_next_result = Pump();
+        if (!maybe_next_result.ok()) {
+          return Future<V>::MakeFinished(maybe_next_result.status());
+        }
+        auto maybe_next = std::move(maybe_next_result).ValueUnsafe();
+        if (maybe_next.has_value()) {
+          return Future<V>::MakeFinished(*std::move(maybe_next));
+        }
+
+        auto next_fut = generator_();
+        // If finished already, process results immediately inside the loop to avoid
+        // stack overflow
+        if (next_fut.is_finished()) {
+          auto next_result = next_fut.result();
+          if (next_result.ok()) {
+            last_value_ = *next_result;
+          } else {
+            return Future<V>::MakeFinished(next_result.status());
+          }
+          // Otherwise, if not finished immediately, add callback to process results
+        } else {
+          auto self = this->shared_from_this();
+          return next_fut.Then([self](const T& next_result) {
+            self->last_value_ = next_result;
+            return (*self)();
+          });
+        }
+      }
+    }
+
+    // See comment on TransformingIterator::Pump
+    Result<std::optional<V>> Pump() {
+      if (!finished_ && last_value_.has_value()) {
+        ARROW_ASSIGN_OR_RAISE(TransformFlow<V> next, transformer_(*last_value_));
+        if (next.ReadyForNext()) {
+          if (IsIterationEnd(*last_value_)) {
+            finished_ = true;
+          }
+          last_value_.reset();
+        }
+        if (next.Finished()) {
+          finished_ = true;
+        }
+        if (next.HasValue()) {
+          return next.Value();
+        }
+      }
+      if (finished_) {
+        return IterationTraits<V>::End();
+      }
+      return std::nullopt;
+    }
+
+    AsyncGenerator<T> generator_;
+    Transformer<T, V> transformer_;
+    std::optional<T> last_value_;
+    bool finished_;
+  };
+
+ public:
+  explicit TransformingGenerator(AsyncGenerator<T> generator,
+                                 Transformer<T, V> transformer)
+      : state_(std::make_shared<TransformingGeneratorState>(std::move(generator),
+                                                            std::move(transformer))) {}
+
+  Future<V> operator()() { return (*state_)(); }
+
+ protected:
+  std::shared_ptr<TransformingGeneratorState> state_;
+};
+
+/// \brief Transform an async generator using a transformer function returning a new
+/// AsyncGenerator
+///
+/// The transform function here behaves exactly the same as the transform function in
+/// MakeTransformedIterator and you can safely use the same transform function to
+/// transform both synchronous and asynchronous streams.
+///
+/// This generator is not async-reentrant
+///
+/// This generator may queue up to 1 instance of T but will not delay
+template <typename T, typename V>
+AsyncGenerator<V> MakeTransformedGenerator(AsyncGenerator<T> generator,
+                                           Transformer<T, V> transformer) {
+  return TransformingGenerator<T, V>(generator, transformer);
+}
+
+/// \see MakeSerialReadaheadGenerator
+template <typename T>
+class SerialReadaheadGenerator {
+ public:
+  SerialReadaheadGenerator(AsyncGenerator<T> source_generator, int max_readahead)
+      : state_(std::make_shared<State>(std::move(source_generator), max_readahead)) {}
+
+  Future<T> operator()() {
+    if (state_->first_) {
+      // Lazy generator, need to wait for the first ask to prime the pump
+      state_->first_ = false;
+      auto next = state_->source_();
+      return next.Then(Callback{state_}, ErrCallback{state_});
+    }
+
+    // This generator is not async-reentrant.  We won't be called until the last
+    // future finished so we know there is something in the queue
+    auto finished = state_->finished_.load();
+    if (finished && state_->readahead_queue_.IsEmpty()) {
+      return AsyncGeneratorEnd<T>();
+    }
+
+    std::shared_ptr<Future<T>> next;
+    if (!state_->readahead_queue_.Read(next)) {
+      return Status::UnknownError("Could not read from readahead_queue");
+    }
+
+    auto last_available = state_->spaces_available_.fetch_add(1);
+    if (last_available == 0 && !finished) {
+      // Reader idled out, we need to restart it
+      ARROW_RETURN_NOT_OK(state_->Pump(state_));
+    }
+    return *next;
+  }
+
+ private:
+  struct State {
+    State(AsyncGenerator<T> source, int max_readahead)
+        : first_(true),
+          source_(std::move(source)),
+          finished_(false),
+          // There is one extra "space" for the in-flight request
+          spaces_available_(max_readahead + 1),
+          // The SPSC queue has size-1 "usable" slots so we need to overallocate 1
+          readahead_queue_(max_readahead + 1) {}
+
+    Status Pump(const std::shared_ptr<State>& self) {
+      // Can't do readahead_queue.write(source().Then(...)) because then the
+      // callback might run immediately and add itself to the queue before this gets added
+      // to the queue messing up the order.
+      auto next_slot = std::make_shared<Future<T>>();
+      auto written = readahead_queue_.Write(next_slot);
+      if (!written) {
+        return Status::UnknownError("Could not write to readahead_queue");
+      }
+      // If this Pump is being called from a callback it is possible for the source to
+      // poll and read from the queue between the Write and this spot where we fill the
+      // value in. However, it is not possible for the future to read this value we are
+      // writing.  That is because this callback (the callback for future X) must be
+      // finished before future X is marked complete and this source is not pulled
+      // reentrantly so it will not poll for future X+1 until this callback has completed.
+      *next_slot = source_().Then(Callback{self}, ErrCallback{self});
+      return Status::OK();
+    }
+
+    // Only accessed by the consumer end
+    bool first_;
+    // Accessed by both threads
+    AsyncGenerator<T> source_;
+    std::atomic<bool> finished_;
+    // The queue has a size but it is not atomic.  We keep track of how many spaces are
+    // left in the queue here so we know if we've just written the last value and we need
+    // to stop reading ahead or if we've just read from a full queue and we need to
+    // restart reading ahead
+    std::atomic<uint32_t> spaces_available_;
+    // Needs to be a queue of shared_ptr and not Future because we set the value of the
+    // future after we add it to the queue
+    util::SpscQueue<std::shared_ptr<Future<T>>> readahead_queue_;
+  };
+
+  struct Callback {
+    Result<T> operator()(const T& next) {
+      if (IsIterationEnd(next)) {
+        state_->finished_.store(true);
+        return next;
+      }
+      auto last_available = state_->spaces_available_.fetch_sub(1);
+      if (last_available > 1) {
+        ARROW_RETURN_NOT_OK(state_->Pump(state_));
+      }
+      return next;
+    }
+
+    std::shared_ptr<State> state_;
+  };
+
+  struct ErrCallback {
+    Result<T> operator()(const Status& st) {
+      state_->finished_.store(true);
+      return st;
+    }
+
+    std::shared_ptr<State> state_;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// \see MakeFromFuture
+template <typename T>
+class FutureFirstGenerator {
+ public:
+  explicit FutureFirstGenerator(Future<AsyncGenerator<T>> future)
+      : state_(std::make_shared<State>(std::move(future))) {}
+
+  Future<T> operator()() {
+    if (state_->source_) {
+      return state_->source_();
+    } else {
+      auto state = state_;
+      return state_->future_.Then([state](const AsyncGenerator<T>& source) {
+        state->source_ = source;
+        return state->source_();
+      });
+    }
+  }
+
+ private:
+  struct State {
+    explicit State(Future<AsyncGenerator<T>> future) : future_(future), source_() {}
+
+    Future<AsyncGenerator<T>> future_;
+    AsyncGenerator<T> source_;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// \brief Transform a Future<AsyncGenerator<T>> into an AsyncGenerator<T>
+/// that waits for the future to complete as part of the first item.
+///
+/// This generator is not async-reentrant (even if the generator yielded by future is)
+///
+/// This generator does not queue
+template <typename T>
+AsyncGenerator<T> MakeFromFuture(Future<AsyncGenerator<T>> future) {
+  return FutureFirstGenerator<T>(std::move(future));
+}
+
+/// \brief Create a generator that will pull from the source into a queue.  Unlike
+/// MakeReadaheadGenerator this will not pull reentrantly from the source.
+///
+/// The source generator does not need to be async-reentrant
+///
+/// This generator is not async-reentrant (even if the source is)
+///
+/// This generator may queue up to max_readahead additional instances of T
+template <typename T>
+AsyncGenerator<T> MakeSerialReadaheadGenerator(AsyncGenerator<T> source_generator,
+                                               int max_readahead) {
+  return SerialReadaheadGenerator<T>(std::move(source_generator), max_readahead);
+}
+
+/// \brief Create a generator that immediately pulls from the source
+///
+/// Typical generators do not pull from their source until they themselves
+/// are pulled.  This generator does not follow that convention and will call
+/// generator() once before it returns.  The returned generator will otherwise
+/// mirror the source.
+///
+/// This generator forwards async-reentrant pressure to the source
+/// This generator buffers one item (the first result) until it is delivered.
+template <typename T>
+AsyncGenerator<T> MakeAutoStartingGenerator(AsyncGenerator<T> generator) {
+  struct AutostartGenerator {
+    Future<T> operator()() {
+      if (first_future->is_valid()) {
+        Future<T> result = *first_future;
+        *first_future = Future<T>();
+        return result;
+      }
+      return source();
+    }
+
+    std::shared_ptr<Future<T>> first_future;
+    AsyncGenerator<T> source;
+  };
+
+  std::shared_ptr<Future<T>> first_future = std::make_shared<Future<T>>(generator());
+  return AutostartGenerator{std::move(first_future), std::move(generator)};
+}
+
+/// \see MakeReadaheadGenerator
+template <typename T>
+class ReadaheadGenerator {
+ public:
+  ReadaheadGenerator(AsyncGenerator<T> source_generator, int max_readahead)
+      : state_(std::make_shared<State>(std::move(source_generator), max_readahead)) {}
+
+  Future<T> AddMarkFinishedContinuation(Future<T> fut) {
+    auto state = state_;
+    return fut.Then(
+        [state](const T& result) -> Future<T> {
+          state->MarkFinishedIfDone(result);
+          if (state->finished.load()) {
+            if (state->num_running.fetch_sub(1) == 1) {
+              state->final_future.MarkFinished();
+            }
+          } else {
+            state->num_running.fetch_sub(1);
+          }
+          return result;
+        },
+        [state](const Status& err) -> Future<T> {
+          // If there is an error we need to make sure all running
+          // tasks finish before we return the error.
+          state->finished.store(true);
+          if (state->num_running.fetch_sub(1) == 1) {
+            state->final_future.MarkFinished();
+          }
+          return state->final_future.Then([err]() -> Result<T> { return err; });
+        });
+  }
+
+  Future<T> operator()() {
+    if (state_->readahead_queue.empty()) {
+      // This is the first request, let's pump the underlying queue
+      state_->num_running.store(state_->max_readahead);
+      for (int i = 0; i < state_->max_readahead; i++) {
+        auto next = state_->source_generator();
+        auto next_after_check = AddMarkFinishedContinuation(std::move(next));
+        state_->readahead_queue.push(std::move(next_after_check));
+      }
+    }
+    // Pop one and add one
+    auto result = state_->readahead_queue.front();
+    state_->readahead_queue.pop();
+    if (state_->finished.load()) {
+      state_->readahead_queue.push(AsyncGeneratorEnd<T>());
+    } else {
+      state_->num_running.fetch_add(1);
+      auto back_of_queue = state_->source_generator();
+      auto back_of_queue_after_check =
+          AddMarkFinishedContinuation(std::move(back_of_queue));
+      state_->readahead_queue.push(std::move(back_of_queue_after_check));
+    }
+    return result;
+  }
+
+ private:
+  struct State {
+    State(AsyncGenerator<T> source_generator, int max_readahead)
+        : source_generator(std::move(source_generator)), max_readahead(max_readahead) {}
+
+    void MarkFinishedIfDone(const T& next_result) {
+      if (IsIterationEnd(next_result)) {
+        finished.store(true);
+      }
+    }
+
+    AsyncGenerator<T> source_generator;
+    int max_readahead;
+    Future<> final_future = Future<>::Make();
+    std::atomic<int> num_running{0};
+    std::atomic<bool> finished{false};
+    std::queue<Future<T>> readahead_queue;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// \brief A generator where the producer pushes items on a queue.
+///
+/// No back-pressure is applied, so this generator is mostly useful when
+/// producing the values is neither CPU- nor memory-expensive (e.g. fetching
+/// filesystem metadata).
+///
+/// This generator is not async-reentrant.
+template <typename T>
+class PushGenerator {
+  struct State {
+    State() {}
+
+    util::Mutex mutex;
+    std::deque<Result<T>> result_q;
+    std::optional<Future<T>> consumer_fut;
+    bool finished = false;
+  };
+
+ public:
+  /// Producer API for PushGenerator
+  class Producer {
+   public:
+    explicit Producer(const std::shared_ptr<State>& state) : weak_state_(state) {}
+
+    /// \brief Push a value on the queue
+    ///
+    /// True is returned if the value was pushed, false if the generator is
+    /// already closed or destroyed.  If the latter, it is recommended to stop
+    /// producing any further values.
+    bool Push(Result<T> result) {
+      auto state = weak_state_.lock();
+      if (!state) {
+        // Generator was destroyed
+        return false;
+      }
+      auto lock = state->mutex.Lock();
+      if (state->finished) {
+        // Closed early
+        return false;
+      }
+      if (state->consumer_fut.has_value()) {
+        auto fut = std::move(state->consumer_fut.value());
+        state->consumer_fut.reset();
+        lock.Unlock();  // unlock before potentially invoking a callback
+        fut.MarkFinished(std::move(result));
+      } else {
+        state->result_q.push_back(std::move(result));
+      }
+      return true;
+    }
+
+    /// \brief Tell the consumer we have finished producing
+    ///
+    /// It is allowed to call this and later call Push() again ("early close").
+    /// In this case, calls to Push() after the queue is closed are silently
+    /// ignored.  This can help implementing non-trivial cancellation cases.
+    ///
+    /// True is returned on success, false if the generator is already closed
+    /// or destroyed.
+    bool Close() {
+      auto state = weak_state_.lock();
+      if (!state) {
+        // Generator was destroyed
+        return false;
+      }
+      auto lock = state->mutex.Lock();
+      if (state->finished) {
+        // Already closed
+        return false;
+      }
+      state->finished = true;
+      if (state->consumer_fut.has_value()) {
+        auto fut = std::move(state->consumer_fut.value());
+        state->consumer_fut.reset();
+        lock.Unlock();  // unlock before potentially invoking a callback
+        fut.MarkFinished(IterationTraits<T>::End());
+      }
+      return true;
+    }
+
+    /// Return whether the generator was closed or destroyed.
+    bool is_closed() const {
+      auto state = weak_state_.lock();
+      if (!state) {
+        // Generator was destroyed
+        return true;
+      }
+      auto lock = state->mutex.Lock();
+      return state->finished;
+    }
+
+   private:
+    const std::weak_ptr<State> weak_state_;
+  };
+
+  PushGenerator() : state_(std::make_shared<State>()) {}
+
+  /// Read an item from the queue
+  Future<T> operator()() const {
+    auto lock = state_->mutex.Lock();
+    assert(!state_->consumer_fut.has_value());  // Non-reentrant
+    if (!state_->result_q.empty()) {
+      auto fut = Future<T>::MakeFinished(std::move(state_->result_q.front()));
+      state_->result_q.pop_front();
+      return fut;
+    }
+    if (state_->finished) {
+      return AsyncGeneratorEnd<T>();
+    }
+    auto fut = Future<T>::Make();
+    state_->consumer_fut = fut;
+    return fut;
+  }
+
+  /// \brief Return producer-side interface
+  ///
+  /// The returned object must be used by the producer to push values on the queue.
+  /// Only a single Producer object should be instantiated.
+  Producer producer() { return Producer{state_}; }
+
+ private:
+  const std::shared_ptr<State> state_;
+};
+
+/// \brief Create a generator that pulls reentrantly from a source
+/// This generator will pull reentrantly from a source, ensuring that max_readahead
+/// requests are active at any given time.
+///
+/// The source generator must be async-reentrant
+///
+/// This generator itself is async-reentrant.
+///
+/// This generator may queue up to max_readahead instances of T
+template <typename T>
+AsyncGenerator<T> MakeReadaheadGenerator(AsyncGenerator<T> source_generator,
+                                         int max_readahead) {
+  return ReadaheadGenerator<T>(std::move(source_generator), max_readahead);
+}
+
+/// \brief Creates a generator that will yield finished futures from a vector
+///
+/// This generator is async-reentrant
+template <typename T>
+AsyncGenerator<T> MakeVectorGenerator(std::vector<T> vec) {
+  struct State {
+    explicit State(std::vector<T> vec_) : vec(std::move(vec_)), vec_idx(0) {}
+
+    std::vector<T> vec;
+    std::atomic<std::size_t> vec_idx;
+  };
+
+  auto state = std::make_shared<State>(std::move(vec));
+  return [state]() {
+    auto idx = state->vec_idx.fetch_add(1);
+    if (idx >= state->vec.size()) {
+      // Eagerly return memory
+      state->vec.clear();
+      return AsyncGeneratorEnd<T>();
+    }
+    return Future<T>::MakeFinished(state->vec[idx]);
+  };
+}
+
+/// \see MakeMergedGenerator
+template <typename T>
+class MergedGenerator {
+  // Note, the implementation of this class is quite complex at the moment (PRs to
+  // simplify are always welcome)
+  //
+  // Terminology is borrowed from rxjs.  This is a pull based implementation of the
+  // mergeAll operator.  The "outer subscription" refers to the async
+  // generator that the caller provided when creating this.  The outer subscription
+  // yields generators.
+  //
+  // Each of these generators is then subscribed to (up to max_subscriptions) and these
+  // are referred to as "inner subscriptions".
+  //
+  // As soon as we start we try and establish `max_subscriptions` inner subscriptions. For
+  // each inner subscription we will cache up to 1 value.  This means we may have more
+  // values than we have been asked for.  In our example, if a caller asks for one record
+  // batch we will start scanning `max_subscriptions` different files.  For each file we
+  // will only queue up to 1 batch (so a separate readahead is needed on the file if batch
+  // readahead is desired).
+  //
+  // If the caller is slow we may accumulate ready-to-deliver items.  These are stored
+  // in `delivered_jobs`.
+  //
+  // If the caller is very quick we may accumulate requests.  These are stored in
+  // `waiting_jobs`.
+  //
+  // It may be helpful to consider an example, in the scanner the outer subscription
+  // is some kind of asynchronous directory listing.  The inner subscription is
+  // then a scan on a file yielded by the directory listing.
+  //
+  // An "outstanding" request is when we have polled either the inner or outer
+  // subscription but that future hasn't completed yet.
+  //
+  // There are three possible "events" that can happen.
+  // * A caller could request the next future
+  // * An outer callback occurs when the next subscription is ready (e.g. the directory
+  //     listing has produced a new file)
+  // * An inner callback occurs when one of the inner subscriptions emits a value (e.g.
+  //     a file scan emits a record batch)
+  //
+  // Any time an event happens the logic is broken into two phases.  First, we grab the
+  // lock and modify the shared state.  While doing this we figure out what callbacks we
+  // will need to execute.  Then, we give up the lock and execute these callbacks.  It is
+  // important to execute these callbacks without the lock to avoid deadlock.
+ public:
+  explicit MergedGenerator(AsyncGenerator<AsyncGenerator<T>> source,
+                           int max_subscriptions)
+      : state_(std::make_shared<State>(std::move(source), max_subscriptions)) {}
+
+  Future<T> operator()() {
+    // A caller has requested a future
+    Future<T> waiting_future;
+    std::shared_ptr<DeliveredJob> delivered_job;
+    bool mark_generator_complete = false;
+    {
+      auto guard = state_->mutex.Lock();
+      if (!state_->delivered_jobs.empty()) {
+        // If we have a job sitting around we can deliver it
+        delivered_job = std::move(state_->delivered_jobs.front());
+        state_->delivered_jobs.pop_front();
+        if (state_->IsCompleteUnlocked(guard)) {
+          // It's possible this waiting job was the only thing left to handle and
+          // we have now completed the generator.
+          mark_generator_complete = true;
+        } else {
+          // Since we had a job sitting around we also had an inner subscription
+          // that had paused.  We are going to restart this inner subscription and
+          // so there will be a new outstanding request.
+          state_->outstanding_requests++;
+        }
+      } else if (state_->broken ||
+                 (!state_->first && state_->num_running_subscriptions == 0)) {
+        // If we are broken or exhausted then prepare a terminal item but
+        // we won't complete it until we've finished.
+        Result<T> end_res = IterationEnd<T>();
+        if (!state_->final_error.ok()) {
+          end_res = state_->final_error;
+          state_->final_error = Status::OK();
+        }
+        return state_->all_finished.Then([end_res]() -> Result<T> { return end_res; });
+      } else {
+        // Otherwise we just queue the request and it will be completed when one of the
+        // ongoing inner subscriptions delivers a result
+        waiting_future = Future<T>::Make();
+        state_->waiting_jobs.push_back(std::make_shared<Future<T>>(waiting_future));
+      }
+      if (state_->first) {
+        // On the first request we are going to try and immediately fill our queue
+        // of subscriptions.  We assume we are going to be able to start them all.
+        state_->outstanding_requests +=
+            static_cast<int>(state_->active_subscriptions.size());
+        state_->num_running_subscriptions +=
+            static_cast<int>(state_->active_subscriptions.size());
+      }
+    }
+    // If we grabbed a finished item from the delivered_jobs queue then we may need
+    // to mark the generator finished or issue a request for a new item to fill in
+    // the spot we just vacated.  Notice that we issue that request to the same
+    // subscription that delivered it (deliverer).
+    if (delivered_job) {
+      if (mark_generator_complete) {
+        state_->all_finished.MarkFinished();
+      } else {
+        delivered_job->deliverer().AddCallback(
+            InnerCallback(state_, delivered_job->index));
+      }
+      return std::move(delivered_job->value);
+    }
+    // On the first call we try and fill up our subscriptions.  It's possible the outer
+    // generator only has a few items and we can't fill up to what we were hoping.  In
+    // that case we have to bail early.
+    if (state_->first) {
+      state_->first = false;
+      mark_generator_complete = false;
+      for (int i = 0; i < static_cast<int>(state_->active_subscriptions.size()); i++) {
+        state_->PullSource().AddCallback(
+            OuterCallback{state_, static_cast<std::size_t>(i)});
+        // If we have to bail early then we need to update the shared state again so
+        // we need to reacquire the lock.
+        auto guard = state_->mutex.Lock();
+        if (state_->source_exhausted) {
+          int excess_requests =
+              static_cast<int>(state_->active_subscriptions.size()) - i - 1;
+          state_->outstanding_requests -= excess_requests;
+          state_->num_running_subscriptions -= excess_requests;
+          if (excess_requests > 0) {
+            // It's possible that we are completing the generator by reducing the number
+            // of outstanding requests (e.g. this happens when the outer subscription and
+            // all inner subscriptions are synchronous)
+            mark_generator_complete = state_->IsCompleteUnlocked(guard);
+          }
+          break;
+        }
+      }
+      if (mark_generator_complete) {
+        state_->MarkFinishedAndPurge();
+      }
+    }
+    return waiting_future;
+  }
+
+ private:
+  struct DeliveredJob {
+    explicit DeliveredJob(AsyncGenerator<T> deliverer_, Result<T> value_,
+                          std::size_t index_)
+        : deliverer(deliverer_), value(std::move(value_)), index(index_) {}
+
+    // The generator that delivered this result, we will request another item
+    // from this generator once the result is delivered
+    AsyncGenerator<T> deliverer;
+    // The result we received from the generator
+    Result<T> value;
+    // The index of the generator (in active_subscriptions) that delivered this
+    // result.  This is used if we need to replace a finished generator.
+    std::size_t index;
+  };
+
+  struct State {
+    State(AsyncGenerator<AsyncGenerator<T>> source, int max_subscriptions)
+        : source(std::move(source)),
+          active_subscriptions(max_subscriptions),
+          delivered_jobs(),
+          waiting_jobs(),
+          mutex(),
+          first(true),
+          broken(false),
+          source_exhausted(false),
+          outstanding_requests(0),
+          num_running_subscriptions(0),
+          final_error(Status::OK()) {}
+
+    Future<AsyncGenerator<T>> PullSource() {
+      // Need to guard access to source() so we don't pull sync-reentrantly which
+      // is never valid.
+      auto lock = mutex.Lock();
+      return source();
+    }
+
+    void SignalErrorUnlocked(const util::Mutex::Guard& guard) {
+      broken = true;
+      // Empty any results that have arrived but not asked for.
+      while (!delivered_jobs.empty()) {
+        delivered_jobs.pop_front();
+      }
+    }
+
+    // This function is called outside the mutex but it will only ever be
+    // called once
+    void MarkFinishedAndPurge() {
+      all_finished.MarkFinished();
+      while (!waiting_jobs.empty()) {
+        waiting_jobs.front()->MarkFinished(IterationEnd<T>());
+        waiting_jobs.pop_front();
+      }
+    }
+
+    // This is called outside the mutex but it is only ever called
+    // once and Future<>::AddCallback is thread-safe
+    void MarkFinalError(const Status& err, Future<T> maybe_sink) {
+      if (maybe_sink.is_valid()) {
+        // Someone is waiting for this error so lets mark it complete when
+        // all the work is done
+        all_finished.AddCallback([maybe_sink, err](const Status& status) mutable {
+          maybe_sink.MarkFinished(err);
+        });
+      } else {
+        // No one is waiting for this error right now so it will be delivered
+        // next.
+        final_error = err;
+      }
+    }
+
+    bool IsCompleteUnlocked(const util::Mutex::Guard& guard) {
+      return outstanding_requests == 0 &&
+             (broken || (source_exhausted && num_running_subscriptions == 0 &&
+                         delivered_jobs.empty()));
+    }
+
+    bool MarkTaskFinishedUnlocked(const util::Mutex::Guard& guard) {
+      --outstanding_requests;
+      return IsCompleteUnlocked(guard);
+    }
+
+    // The outer generator.  Each item we pull from this will be its own generator
+    // and become an inner subscription
+    AsyncGenerator<AsyncGenerator<T>> source;
+    // active_subscriptions and delivered_jobs will be bounded by max_subscriptions
+    std::vector<AsyncGenerator<T>> active_subscriptions;
+    // Results delivered by the inner subscriptions that weren't yet asked for by the
+    // caller
+    std::deque<std::shared_ptr<DeliveredJob>> delivered_jobs;
+    // waiting_jobs is unbounded, reentrant pulls (e.g. AddReadahead) will provide the
+    // backpressure
+    std::deque<std::shared_ptr<Future<T>>> waiting_jobs;
+    // A future that will be marked complete when the terminal item has arrived and all
+    // outstanding futures have completed.  It is used to hold off emission of an error
+    // until all outstanding work is done.
+    Future<> all_finished = Future<>::Make();
+    util::Mutex mutex;
+    // A flag cleared when the caller firsts asks for a future.  Used to start polling.
+    bool first;
+    // A flag set when an error arrives, prevents us from issuing new requests.
+    bool broken;
+    // A flag set when the outer subscription has been exhausted.  Prevents us from
+    // pulling it further (even though it would be generally harmless) and lets us know we
+    // are finishing up.
+    bool source_exhausted;
+    // The number of futures that we have requested from either the outer or inner
+    // subscriptions that have not yet completed.  We cannot mark all_finished until this
+    // reaches 0.  This will never be greater than max_subscriptions
+    int outstanding_requests;
+    // The number of running subscriptions.  We ramp this up to `max_subscriptions` as
+    // soon as the first item is requested and then it stays at that level (each exhausted
+    // inner subscription is replaced by a new inner subscription) until the outer
+    // subscription is exhausted at which point this descends to 0 (and source_exhausted)
+    // is then set to true.
+    int num_running_subscriptions;
+    // If an error arrives, and the caller hasn't asked for that item, we store the error
+    // here.  It is analagous to delivered_jobs but for errors instead of finished
+    // results.
+    Status final_error;
+  };
+
+  struct InnerCallback {
+    InnerCallback(std::shared_ptr<State> state, std::size_t index, bool recursive = false)
+        : state(std::move(state)), index(index), recursive(recursive) {}
+
+    void operator()(const Result<T>& maybe_next_ref) {
+      // An item has been delivered by one of the inner subscriptions
+      Future<T> next_fut;
+      const Result<T>* maybe_next = &maybe_next_ref;
+
+      // When an item is delivered (and the caller has asked for it) we grab the
+      // next item from the inner subscription.  To avoid this behavior leading to an
+      // infinite loop (this can happen if the caller's callback asks for the next item)
+      // we use a while loop.
+      while (true) {
+        Future<T> sink;
+        bool sub_finished = maybe_next->ok() && IsIterationEnd(**maybe_next);
+        bool pull_next_sub = false;
+        bool was_broken = false;
+        bool should_mark_gen_complete = false;
+        bool should_mark_final_error = false;
+        {
+          auto guard = state->mutex.Lock();
+          if (state->broken) {
+            // We've errored out previously so ignore the result.  If anyone was waiting
+            // for this they will get IterationEnd when we purge
+            was_broken = true;
+          } else {
+            if (!sub_finished) {
+              // There is a result to deliver.  Either we can deliver it now or we will
+              // queue it up
+              if (state->waiting_jobs.empty()) {
+                state->delivered_jobs.push_back(std::make_shared<DeliveredJob>(
+                    state->active_subscriptions[index], *maybe_next, index));
+              } else {
+                sink = std::move(*state->waiting_jobs.front());
+                state->waiting_jobs.pop_front();
+              }
+            }
+
+            // If this is the first error then we transition the state to a broken state
+            if (!maybe_next->ok()) {
+              should_mark_final_error = true;
+              state->SignalErrorUnlocked(guard);
+            }
+          }
+
+          // If we finished this inner subscription then we need to grab a new inner
+          // subscription to take its spot.  If we can't (because we're broken or
+          // exhausted) then we aren't going to be starting any new futures and so
+          // the number of running subscriptions drops.
+          pull_next_sub = sub_finished && !state->source_exhausted && !was_broken;
+          if (sub_finished && !pull_next_sub) {
+            state->num_running_subscriptions--;
+          }
+          // There are three situations we won't pull again.  If an error occurred or we
+          // are already finished or if no one was waiting for our result and so we queued
+          // it up.  We will decrement outstanding_requests and possibly mark the
+          // generator completed.
+          if (state->broken || (!sink.is_valid() && !sub_finished) ||
+              (sub_finished && state->source_exhausted)) {
+            if (state->MarkTaskFinishedUnlocked(guard)) {
+              should_mark_gen_complete = true;
+            }
+          }
+        }
+
+        // Now we have given up the lock and we can take all the actions we decided we
+        // need to take.
+        if (should_mark_final_error) {
+          state->MarkFinalError(maybe_next->status(), std::move(sink));
+        }
+
+        if (should_mark_gen_complete) {
+          state->MarkFinishedAndPurge();
+        }
+
+        // An error occurred elsewhere so there is no need to mark any future
+        // finished (will happen during the purge) or pull from anything
+        if (was_broken) {
+          return;
+        }
+
+        if (pull_next_sub) {
+          if (recursive) {
+            was_empty = true;
+            return;
+          }
+          // We pulled an end token so we need to start a new subscription
+          // in our spot
+          state->PullSource().AddCallback(OuterCallback{state, index});
+        } else if (sink.is_valid()) {
+          // We pulled a valid result and there was someone waiting for it
+          // so lets fetch the next result from our subscription
+          sink.MarkFinished(*maybe_next);
+          next_fut = state->active_subscriptions[index]();
+          if (next_fut.TryAddCallback([this]() { return InnerCallback(state, index); })) {
+            return;
+          }
+          // Already completed. Avoid very deep recursion by looping
+          // here instead of relying on the callback.
+          maybe_next = &next_fut.result();
+          continue;
+        }
+        // else: We pulled a valid result but no one was waiting for it so
+        // we can just stop.
+        return;
+      }
+    }
+    std::shared_ptr<State> state;
+    std::size_t index;
+    bool recursive;
+    bool was_empty = false;
+  };
+
+  struct OuterCallback {
+    void operator()(const Result<AsyncGenerator<T>>& initial_maybe_next) {
+      Result<AsyncGenerator<T>> maybe_next = initial_maybe_next;
+      while (true) {
+        // We have been given a new inner subscription
+        bool should_continue = false;
+        bool should_mark_gen_complete = false;
+        bool should_deliver_error = false;
+        bool source_exhausted = maybe_next.ok() && IsIterationEnd(*maybe_next);
+        Future<T> error_sink;
+        {
+          auto guard = state->mutex.Lock();
+          if (!maybe_next.ok() || source_exhausted || state->broken) {
+            // If here then we will not pull any more from the outer source
+            if (!state->broken && !maybe_next.ok()) {
+              state->SignalErrorUnlocked(guard);
+              // If here then we are the first error so we need to deliver it
+              should_deliver_error = true;
+              if (!state->waiting_jobs.empty()) {
+                error_sink = std::move(*state->waiting_jobs.front());
+                state->waiting_jobs.pop_front();
+              }
+            }
+            if (source_exhausted) {
+              state->source_exhausted = true;
+              state->num_running_subscriptions--;
+            }
+            if (state->MarkTaskFinishedUnlocked(guard)) {
+              should_mark_gen_complete = true;
+            }
+          } else {
+            state->active_subscriptions[index] = *maybe_next;
+            should_continue = true;
+          }
+        }
+        if (should_deliver_error) {
+          state->MarkFinalError(maybe_next.status(), std::move(error_sink));
+        }
+        if (should_mark_gen_complete) {
+          state->MarkFinishedAndPurge();
+        }
+        if (should_continue) {
+          // There is a possibility that a large sequence of immediately available inner
+          // callbacks could lead to a stack overflow.  To avoid this we need to
+          // synchronously loop through inner/outer callbacks until we either find an
+          // unfinished future or we find an actual item to deliver.
+          Future<T> next_item = (*maybe_next)();
+          if (!next_item.TryAddCallback([this] { return InnerCallback(state, index); })) {
+            // By setting recursive to true we signal to the inner callback that, if it is
+            // empty, instead of adding a new outer callback, it should just immediately
+            // return, flagging was_empty so that we know we need to check the next
+            // subscription.
+            InnerCallback immediate_inner(state, index, /*recursive=*/true);
+            immediate_inner(next_item.result());
+            if (immediate_inner.was_empty) {
+              Future<AsyncGenerator<T>> next_source = state->PullSource();
+              if (next_source.TryAddCallback([this] {
+                    return OuterCallback{state, index};
+                  })) {
+                // We hit an unfinished future so we can stop looping
+                return;
+              }
+              // The current subscription was immediately and synchronously empty
+              // and we were able to synchronously pull the next subscription so we
+              // can keep looping.
+              maybe_next = next_source.result();
+              continue;
+            }
+          }
+        }
+        return;
+      }
+    }
+    std::shared_ptr<State> state;
+    std::size_t index;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// \brief Create a generator that takes in a stream of generators and pulls from up to
+/// max_subscriptions at a time
+///
+/// Note: This may deliver items out of sequence. For example, items from the third
+/// AsyncGenerator generated by the source may be emitted before some items from the first
+/// AsyncGenerator generated by the source.
+///
+/// This generator will pull from source async-reentrantly unless max_subscriptions is 1
+/// This generator will not pull from the individual subscriptions reentrantly.  Add
+/// readahead to the individual subscriptions if that is desired.
+/// This generator is async-reentrant
+///
+/// This generator may queue up to max_subscriptions instances of T
+template <typename T>
+AsyncGenerator<T> MakeMergedGenerator(AsyncGenerator<AsyncGenerator<T>> source,
+                                      int max_subscriptions) {
+  return MergedGenerator<T>(std::move(source), max_subscriptions);
+}
+
+template <typename T>
+Result<AsyncGenerator<T>> MakeSequencedMergedGenerator(
+    AsyncGenerator<AsyncGenerator<T>> source, int max_subscriptions) {
+  if (max_subscriptions < 0) {
+    return Status::Invalid("max_subscriptions must be a positive integer");
+  }
+  if (max_subscriptions == 1) {
+    return Status::Invalid("Use MakeConcatenatedGenerator if max_subscriptions is 1");
+  }
+  AsyncGenerator<AsyncGenerator<T>> autostarting_source = MakeMappedGenerator(
+      std::move(source),
+      [](const AsyncGenerator<T>& sub) { return MakeAutoStartingGenerator(sub); });
+  AsyncGenerator<AsyncGenerator<T>> sub_readahead =
+      MakeSerialReadaheadGenerator(std::move(autostarting_source), max_subscriptions - 1);
+  return MakeConcatenatedGenerator(std::move(sub_readahead));
+}
+
+/// \brief Create a generator that takes in a stream of generators and pulls from each
+/// one in sequence.
+///
+/// This generator is async-reentrant but will never pull from source reentrantly and
+/// will never pull from any subscription reentrantly.
+///
+/// This generator may queue 1 instance of T
+///
+/// TODO: Could potentially make a bespoke implementation instead of MergedGenerator that
+/// forwards async-reentrant requests instead of buffering them (which is what
+/// MergedGenerator does)
+template <typename T>
+AsyncGenerator<T> MakeConcatenatedGenerator(AsyncGenerator<AsyncGenerator<T>> source) {
+  return MergedGenerator<T>(std::move(source), 1);
+}
+
+template <typename T>
+struct Enumerated {
+  T value;
+  int index;
+  bool last;
+};
+
+template <typename T>
+struct IterationTraits<Enumerated<T>> {
+  static Enumerated<T> End() { return Enumerated<T>{IterationEnd<T>(), -1, false}; }
+  static bool IsEnd(const Enumerated<T>& val) { return val.index < 0; }
+};
+
+/// \see MakeEnumeratedGenerator
+template <typename T>
+class EnumeratingGenerator {
+ public:
+  EnumeratingGenerator(AsyncGenerator<T> source, T initial_value)
+      : state_(std::make_shared<State>(std::move(source), std::move(initial_value))) {}
+
+  Future<Enumerated<T>> operator()() {
+    if (state_->finished) {
+      return AsyncGeneratorEnd<Enumerated<T>>();
+    } else {
+      auto state = state_;
+      return state->source().Then([state](const T& next) {
+        auto finished = IsIterationEnd<T>(next);
+        auto prev = Enumerated<T>{state->prev_value, state->prev_index, finished};
+        state->prev_value = next;
+        state->prev_index++;
+        state->finished = finished;
+        return prev;
+      });
+    }
+  }
+
+ private:
+  struct State {
+    State(AsyncGenerator<T> source, T initial_value)
+        : source(std::move(source)), prev_value(std::move(initial_value)), prev_index(0) {
+      finished = IsIterationEnd<T>(prev_value);
+    }
+
+    AsyncGenerator<T> source;
+    T prev_value;
+    int prev_index;
+    bool finished;
+  };
+
+  std::shared_ptr<State> state_;
+};
+
+/// Wrap items from a source generator with positional information
+///
+/// When used with MakeMergedGenerator and MakeSequencingGenerator this allows items to be
+/// processed in a "first-available" fashion and later resequenced which can reduce the
+/// impact of sources with erratic performance (e.g. a filesystem where some items may
+/// take longer to read than others).
+///
+/// TODO(ARROW-12371) Would require this generator be async-reentrant
+///
+/// \see MakeSequencingGenerator for an example of putting items back in order
+///
+/// This generator is not async-reentrant
+///
+/// This generator buffers one item (so it knows which item is the last item)
+template <typename T>
+AsyncGenerator<Enumerated<T>> MakeEnumeratedGenerator(AsyncGenerator<T> source) {
+  return FutureFirstGenerator<Enumerated<T>>(
+      source().Then([source](const T& initial_value) -> AsyncGenerator<Enumerated<T>> {
+        return EnumeratingGenerator<T>(std::move(source), initial_value);
+      }));
+}
+
+/// \see MakeTransferredGenerator
+template <typename T>
+class TransferringGenerator {
+ public:
+  explicit TransferringGenerator(AsyncGenerator<T> source, internal::Executor* executor)
+      : source_(std::move(source)), executor_(executor) {}
+
+  Future<T> operator()() { return executor_->Transfer(source_()); }
+
+ private:
+  AsyncGenerator<T> source_;
+  internal::Executor* executor_;
+};
+
+/// \brief Transfer a future to an underlying executor.
+///
+/// Continuations run on the returned future will be run on the given executor
+/// if they cannot be run synchronously.
+///
+/// This is often needed to move computation off I/O threads or other external
+/// completion sources and back on to the CPU executor so the I/O thread can
+/// stay busy and focused on I/O
+///
+/// Keep in mind that continuations called on an already completed future will
+/// always be run synchronously and so no transfer will happen in that case.
+///
+/// This generator is async reentrant if the source is
+///
+/// This generator will not queue
+template <typename T>
+AsyncGenerator<T> MakeTransferredGenerator(AsyncGenerator<T> source,
+                                           internal::Executor* executor) {
+  return TransferringGenerator<T>(std::move(source), executor);
+}
+
+/// \see MakeBackgroundGenerator
+template <typename T>
+class BackgroundGenerator {
+ public:
+  explicit BackgroundGenerator(Iterator<T> it, internal::Executor* io_executor, int max_q,
+                               int q_restart)
+      : state_(std::make_shared<State>(io_executor, std::move(it), max_q, q_restart)),
+        cleanup_(std::make_shared<Cleanup>(state_.get())) {}
+
+  Future<T> operator()() {
+    auto guard = state_->mutex.Lock();
+    Future<T> waiting_future;
+    if (state_->queue.empty()) {
+      if (state_->finished) {
+        return AsyncGeneratorEnd<T>();
+      } else {
+        waiting_future = Future<T>::Make();
+        state_->waiting_future = waiting_future;
+      }
+    } else {
+      auto next = Future<T>::MakeFinished(std::move(state_->queue.front()));
+      state_->queue.pop();
+      if (state_->NeedsRestart()) {
+        return state_->RestartTask(state_, std::move(guard), std::move(next));
+      }
+      return next;
+    }
+    // This should only trigger the very first time this method is called
+    if (state_->NeedsRestart()) {
+      return state_->RestartTask(state_, std::move(guard), std::move(waiting_future));
+    }
+    return waiting_future;
+  }
+
+ protected:
+  static constexpr uint64_t kUnlikelyThreadId{std::numeric_limits<uint64_t>::max()};
+
+  struct State {
+    State(internal::Executor* io_executor, Iterator<T> it, int max_q, int q_restart)
+        : io_executor(io_executor),
+          max_q(max_q),
+          q_restart(q_restart),
+          it(std::move(it)),
+          reading(false),
+          finished(false),
+          should_shutdown(false) {}
+
+    void ClearQueue() {
+      while (!queue.empty()) {
+        queue.pop();
+      }
+    }
+
+    bool TaskIsRunning() const { return task_finished.is_valid(); }
+
+    bool NeedsRestart() const {
+      return !finished && !reading && static_cast<int>(queue.size()) <= q_restart;
+    }
+
+    void DoRestartTask(std::shared_ptr<State> state, util::Mutex::Guard guard) {
+      // If we get here we are actually going to start a new task so let's create a
+      // task_finished future for it
+      state->task_finished = Future<>::Make();
+      state->reading = true;
+      auto spawn_status = io_executor->Spawn(
+          [state]() { BackgroundGenerator::WorkerTask(std::move(state)); });
+      if (!spawn_status.ok()) {
+        // If we can't spawn a new task then send an error to the consumer (either via a
+        // waiting future or the queue) and mark ourselves finished
+        state->finished = true;
+        state->task_finished = Future<>();
+        if (waiting_future.has_value()) {
+          auto to_deliver = std::move(waiting_future.value());
+          waiting_future.reset();
+          guard.Unlock();
+          to_deliver.MarkFinished(spawn_status);
+        } else {
+          ClearQueue();
+          queue.push(spawn_status);
+        }
+      }
+    }
+
+    Future<T> RestartTask(std::shared_ptr<State> state, util::Mutex::Guard guard,
+                          Future<T> next) {
+      if (TaskIsRunning()) {
+        // If the task is still cleaning up we need to wait for it to finish before
+        // restarting.  We also want to block the consumer until we've restarted the
+        // reader to avoid multiple restarts
+        return task_finished.Then([state, next]() {
+          // This may appear dangerous (recursive mutex) but we should be guaranteed the
+          // outer guard has been released by this point.  We know...
+          // * task_finished is not already finished (it would be invalid in that case)
+          // * task_finished will not be marked complete until we've given up the mutex
+          auto guard_ = state->mutex.Lock();
+          state->DoRestartTask(state, std::move(guard_));
+          return next;
+        });
+      }
+      // Otherwise we can restart immediately
+      DoRestartTask(std::move(state), std::move(guard));
+      return next;
+    }
+
+    internal::Executor* io_executor;
+    const int max_q;
+    const int q_restart;
+    Iterator<T> it;
+    std::atomic<uint64_t> worker_thread_id{kUnlikelyThreadId};
+
+    // If true, the task is actively pumping items from the queue and does not need a
+    // restart
+    bool reading;
+    // Set to true when a terminal item arrives
+    bool finished;
+    // Signal to the background task to end early because consumers have given up on it
+    bool should_shutdown;
+    // If the queue is empty, the consumer will create a waiting future and wait for it
+    std::queue<Result<T>> queue;
+    std::optional<Future<T>> waiting_future;
+    // Every background task is given a future to complete when it is entirely finished
+    // processing and ready for the next task to start or for State to be destroyed
+    Future<> task_finished;
+    util::Mutex mutex;
+  };
+
+  // Cleanup task that will be run when all consumer references to the generator are lost
+  struct Cleanup {
+    explicit Cleanup(State* state) : state(state) {}
+    ~Cleanup() {
+      /// TODO: Once ARROW-13109 is available then we can be force consumers to spawn and
+      /// there is no need to perform this check.
+      ///
+      /// It's a deadlock if we enter cleanup from
+      /// the worker thread but it can happen if the consumer doesn't transfer away
+      assert(state->worker_thread_id.load() != ::arrow::internal::GetThreadId());
+      Future<> finish_fut;
+      {
+        auto lock = state->mutex.Lock();
+        if (!state->TaskIsRunning()) {
+          return;
+        }
+        // Signal the current task to stop and wait for it to finish
+        state->should_shutdown = true;
+        finish_fut = state->task_finished;
+      }
+      // Using future as a condition variable here
+      Status st = finish_fut.status();
+      ARROW_UNUSED(st);
+    }
+    State* state;
+  };
+
+  static void WorkerTask(std::shared_ptr<State> state) {
+    state->worker_thread_id.store(::arrow::internal::GetThreadId());
+    // We need to capture the state to read while outside the mutex
+    bool reading = true;
+    while (reading) {
+      auto next = state->it.Next();
+      // Need to capture state->waiting_future inside the mutex to mark finished outside
+      Future<T> waiting_future;
+      {
+        auto guard = state->mutex.Lock();
+
+        if (state->should_shutdown) {
+          state->finished = true;
+          break;
+        }
+
+        if (!next.ok() || IsIterationEnd<T>(*next)) {
+          // Terminal item.  Mark finished to true, send this last item, and quit
+          state->finished = true;
+          if (!next.ok()) {
+            state->ClearQueue();
+          }
+        }
+        // At this point we are going to send an item.  Either we will add it to the
+        // queue or deliver it to a waiting future.
+        if (state->waiting_future.has_value()) {
+          waiting_future = std::move(state->waiting_future.value());
+          state->waiting_future.reset();
+        } else {
+          state->queue.push(std::move(next));
+          // We just filled up the queue so it is time to quit.  We may need to notify
+          // a cleanup task so we transition to Quitting
+          if (static_cast<int>(state->queue.size()) >= state->max_q) {
+            state->reading = false;
+          }
+        }
+        reading = state->reading && !state->finished;
+      }
+      // This should happen outside the mutex.  Presumably there is a
+      // transferring generator on the other end that will quickly transfer any
+      // callbacks off of this thread so we can continue looping.  Still, best not to
+      // rely on that
+      if (waiting_future.is_valid()) {
+        waiting_future.MarkFinished(next);
+      }
+    }
+    // Once we've sent our last item we can notify any waiters that we are done and so
+    // either state can be cleaned up or a new background task can be started
+    Future<> task_finished;
+    {
+      auto guard = state->mutex.Lock();
+      // After we give up the mutex state can be safely deleted.  We will no longer
+      // reference it.  We can safely transition to idle now.
+      task_finished = state->task_finished;
+      state->task_finished = Future<>();
+      state->worker_thread_id.store(kUnlikelyThreadId);
+    }
+    task_finished.MarkFinished();
+  }
+
+  std::shared_ptr<State> state_;
+  // state_ is held by both the generator and the background thread so it won't be cleaned
+  // up when all consumer references are relinquished.  cleanup_ is only held by the
+  // generator so it will be destructed when the last consumer reference is gone.  We use
+  // this to cleanup / stop the background generator in case the consuming end stops
+  // listening (e.g. due to a downstream error)
+  std::shared_ptr<Cleanup> cleanup_;
+};
+
+constexpr int kDefaultBackgroundMaxQ = 32;
+constexpr int kDefaultBackgroundQRestart = 16;
+
+/// \brief Create an AsyncGenerator<T> by iterating over an Iterator<T> on a background
+/// thread
+///
+/// The parameter max_q and q_restart control queue size and background thread task
+/// management. If the background task is fast you typically don't want it creating a
+/// thread task for every item.  Instead the background thread will run until it fills
+/// up a readahead queue.
+///
+/// Once the queue has filled up the background thread task will terminate (allowing other
+/// I/O tasks to use the thread).  Once the queue has been drained enough (specified by
+/// q_restart) then the background thread task will be restarted.  If q_restart is too low
+/// then you may exhaust the queue waiting for the background thread task to start running
+/// again.  If it is too high then it will be constantly stopping and restarting the
+/// background queue task
+///
+/// The "background thread" is a logical thread and will run as tasks on the io_executor.
+/// This thread may stop and start when the queue fills up but there will only be one
+/// active background thread task at any given time.  You MUST transfer away from this
+/// background generator.  Otherwise there could be a race condition if a callback on the
+/// background thread deletes the last consumer reference to the background generator. You
+/// can transfer onto the same executor as the background thread, it is only necessary to
+/// create a new thread task, not to switch executors.
+///
+/// This generator is not async-reentrant
+///
+/// This generator will queue up to max_q blocks
+template <typename T>
+static Result<AsyncGenerator<T>> MakeBackgroundGenerator(
+    Iterator<T> iterator, internal::Executor* io_executor,
+    int max_q = kDefaultBackgroundMaxQ, int q_restart = kDefaultBackgroundQRestart) {
+  if (max_q < q_restart) {
+    return Status::Invalid("max_q must be >= q_restart");
+  }
+  return BackgroundGenerator<T>(std::move(iterator), io_executor, max_q, q_restart);
+}
+
+/// \brief Create an AsyncGenerator<T> by iterating over an Iterator<T> synchronously
+///
+/// This should only be used if you know the source iterator does not involve any
+/// I/O (or other blocking calls).  Otherwise a CPU thread will be blocked and, depending
+/// on the complexity of the iterator, it may lead to deadlock.
+///
+/// If you are not certain if there will be I/O then it is better to use
+/// MakeBackgroundGenerator.  If helpful you can think of this as the AsyncGenerator
+/// equivalent of Future::MakeFinished
+///
+/// It is impossible to call this in an async-reentrant manner since the returned
+/// future will be completed by the time it is polled.
+///
+/// This generator does not queue
+template <typename T>
+static Result<AsyncGenerator<T>> MakeBlockingGenerator(
+    std::shared_ptr<Iterator<T>> iterator) {
+  return [it = std::move(iterator)]() mutable -> Future<T> {
+    return Future<T>::MakeFinished(it->Next());
+  };
+}
+
+template <typename T>
+static Result<AsyncGenerator<T>> MakeBlockingGenerator(Iterator<T> iterator) {
+  return MakeBlockingGenerator(std::make_shared<Iterator<T>>(std::move(iterator)));
+}
+
+/// \see MakeGeneratorIterator
+template <typename T>
+class GeneratorIterator {
+ public:
+  explicit GeneratorIterator(AsyncGenerator<T> source) : source_(std::move(source)) {}
+
+  Result<T> Next() { return source_().result(); }
+
+ private:
+  AsyncGenerator<T> source_;
+};
+
+/// \brief Convert an AsyncGenerator<T> to an Iterator<T> which blocks until each future
+/// is finished
+template <typename T>
+Iterator<T> MakeGeneratorIterator(AsyncGenerator<T> source) {
+  return Iterator<T>(GeneratorIterator<T>(std::move(source)));
+}
+
+/// \brief Add readahead to an iterator using a background thread.
+///
+/// Under the hood this is converting the iterator to a generator using
+/// MakeBackgroundGenerator, adding readahead to the converted generator with
+/// MakeReadaheadGenerator, and then converting back to an iterator using
+/// MakeGeneratorIterator.
+template <typename T>
+Result<Iterator<T>> MakeReadaheadIterator(Iterator<T> it, int readahead_queue_size) {
+  ARROW_ASSIGN_OR_RAISE(auto io_executor, internal::ThreadPool::Make(1));
+  auto max_q = readahead_queue_size;
+  auto q_restart = std::max(1, max_q / 2);
+  ARROW_ASSIGN_OR_RAISE(
+      auto background_generator,
+      MakeBackgroundGenerator(std::move(it), io_executor.get(), max_q, q_restart));
+  // Capture io_executor to keep it alive as long as owned_bg_generator is still
+  // referenced
+  AsyncGenerator<T> owned_bg_generator = [io_executor, background_generator]() {
+    return background_generator();
+  };
+  return MakeGeneratorIterator(std::move(owned_bg_generator));
+}
+
+/// \brief Make a generator that returns a single pre-generated future
+///
+/// This generator is async-reentrant.
+template <typename T>
+std::function<Future<T>()> MakeSingleFutureGenerator(Future<T> future) {
+  assert(future.is_valid());
+  auto state = std::make_shared<Future<T>>(std::move(future));
+  return [state]() -> Future<T> {
+    auto fut = std::move(*state);
+    if (fut.is_valid()) {
+      return fut;
+    } else {
+      return AsyncGeneratorEnd<T>();
+    }
+  };
+}
+
+/// \brief Make a generator that immediately ends.
+///
+/// This generator is async-reentrant.
+template <typename T>
+std::function<Future<T>()> MakeEmptyGenerator() {
+  return []() -> Future<T> { return AsyncGeneratorEnd<T>(); };
+}
+
+/// \brief Make a generator that always fails with a given error
+///
+/// This generator is async-reentrant.
+template <typename T>
+AsyncGenerator<T> MakeFailingGenerator(Status st) {
+  assert(!st.ok());
+  auto state = std::make_shared<Status>(std::move(st));
+  return [state]() -> Future<T> {
+    auto st = std::move(*state);
+    if (!st.ok()) {
+      return std::move(st);
+    } else {
+      return AsyncGeneratorEnd<T>();
+    }
+  };
+}
+
+/// \brief Make a generator that always fails with a given error
+///
+/// This overload allows inferring the return type from the argument.
+template <typename T>
+AsyncGenerator<T> MakeFailingGenerator(const Result<T>& result) {
+  return MakeFailingGenerator<T>(result.status());
+}
+
+/// \brief Prepend initial_values onto a generator
+///
+/// This generator is async-reentrant but will buffer requests and will not
+/// pull from following_values async-reentrantly.
+template <typename T>
+AsyncGenerator<T> MakeGeneratorStartsWith(std::vector<T> initial_values,
+                                          AsyncGenerator<T> following_values) {
+  auto initial_values_vec_gen = MakeVectorGenerator(std::move(initial_values));
+  auto gen_gen = MakeVectorGenerator<AsyncGenerator<T>>(
+      {std::move(initial_values_vec_gen), std::move(following_values)});
+  return MakeConcatenatedGenerator(std::move(gen_gen));
+}
+
+template <typename T>
+struct CancellableGenerator {
+  Future<T> operator()() {
+    if (stop_token.IsStopRequested()) {
+      return stop_token.Poll();
+    }
+    return source();
+  }
+
+  AsyncGenerator<T> source;
+  StopToken stop_token;
+};
+
+/// \brief Allow an async generator to be cancelled
+///
+/// This generator is async-reentrant
+template <typename T>
+AsyncGenerator<T> MakeCancellable(AsyncGenerator<T> source, StopToken stop_token) {
+  return CancellableGenerator<T>{std::move(source), std::move(stop_token)};
+}
+
+template <typename T>
+class DefaultIfEmptyGenerator {
+ public:
+  DefaultIfEmptyGenerator(AsyncGenerator<T> source, T or_value)
+      : state_(std::make_shared<State>(std::move(source), std::move(or_value))) {}
+
+  Future<T> operator()() {
+    if (state_->first) {
+      state_->first = false;
+      struct {
+        T or_value;
+
+        Result<T> operator()(const T& value) {
+          if (IterationTraits<T>::IsEnd(value)) {
+            return std::move(or_value);
+          }
+          return value;
+        }
+      } Continuation;
+      Continuation.or_value = std::move(state_->or_value);
+      return state_->source().Then(std::move(Continuation));
+    }
+    return state_->source();
+  }
+
+ private:
+  struct State {
+    AsyncGenerator<T> source;
+    T or_value;
+    bool first;
+    State(AsyncGenerator<T> source_, T or_value_)
+        : source(std::move(source_)), or_value(std::move(or_value_)), first(true) {}
+  };
+  std::shared_ptr<State> state_;
+};
+
+/// \brief If the generator is empty, return the given value, else
+/// forward the values from the generator.
+///
+/// This generator is async-reentrant.
+template <typename T>
+AsyncGenerator<T> MakeDefaultIfEmptyGenerator(AsyncGenerator<T> source, T or_value) {
+  return DefaultIfEmptyGenerator<T>(std::move(source), std::move(or_value));
+}
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/async_util.h

@@ -0,0 +1,460 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <atomic>
+#include <functional>
+#include <list>
+#include <memory>
+
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/util/cancel.h"
+#include "arrow/util/functional.h"
+#include "arrow/util/future.h"
+#include "arrow/util/iterator.h"
+#include "arrow/util/mutex.h"
+#include "arrow/util/thread_pool.h"
+#include "arrow/util/tracing.h"
+
+namespace arrow {
+
+using internal::FnOnce;
+
+namespace util {
+
+/// A utility which keeps tracks of, and schedules, asynchronous tasks
+///
+/// An asynchronous task has a synchronous component and an asynchronous component.
+/// The synchronous component typically schedules some kind of work on an external
+/// resource (e.g. the I/O thread pool or some kind of kernel-based asynchronous
+/// resource like io_uring).  The asynchronous part represents the work
+/// done on that external resource.  Executing the synchronous part will be referred
+/// to as "submitting the task" since this usually includes submitting the asynchronous
+/// portion to the external thread pool.
+///
+/// By default the scheduler will submit the task (execute the synchronous part) as
+/// soon as it is added, assuming the underlying thread pool hasn't terminated or the
+/// scheduler hasn't aborted.  In this mode, the scheduler is simply acting as
+/// a simple task group.
+///
+/// A task scheduler starts with an initial task.  That task, and all subsequent tasks
+/// are free to add subtasks.  Once all submitted tasks finish the scheduler will
+/// finish.  Note, it is not an error to add additional tasks after a scheduler has
+/// aborted. These tasks will be ignored and never submitted.  The scheduler returns a
+/// future which will complete when all submitted tasks have finished executing.  Once all
+/// tasks have been finished the scheduler is invalid and should no longer be used.
+///
+/// Task failure (either the synchronous portion or the asynchronous portion) will cause
+/// the scheduler to enter an aborted state.  The first such failure will be reported in
+/// the final task future.
+class ARROW_EXPORT AsyncTaskScheduler {
+ public:
+  /// Destructor for AsyncTaskScheduler
+  ///
+  /// The lifetime of the task scheduled is managed automatically.  The scheduler
+  /// will remain valid while any tasks are running (and can always be safely accessed)
+  /// within tasks) and will be destroyed as soon as all tasks have finished.
+  virtual ~AsyncTaskScheduler() = default;
+  /// An interface for a task
+  ///
+  /// Users may want to override this, for example, to add priority
+  /// information for use by a queue.
+  class Task {
+   public:
+    virtual ~Task() = default;
+    /// Submit the task
+    ///
+    /// This will be called by the scheduler at most once when there
+    /// is space to run the task.  This is expected to be a fairly quick
+    /// function that simply submits the actual task work to an external
+    /// resource (e.g. I/O thread pool).
+    ///
+    /// If this call fails then the scheduler will enter an aborted state.
+    virtual Result<Future<>> operator()() = 0;
+    /// The cost of the task
+    ///
+    /// A ThrottledAsyncTaskScheduler can be used to limit the number of concurrent tasks.
+    /// A custom cost may be used, for example, if you would like to limit the number of
+    /// tasks based on the total expected RAM usage of the tasks (this is done in the
+    /// scanner)
+    virtual int cost() const { return 1; }
+    /// The name of the task
+    ///
+    /// This is used for debugging and traceability.  The returned view must remain
+    /// valid for the lifetime of the task.
+    virtual std::string_view name() const = 0;
+
+    /// a span tied to the lifetime of the task, for internal use only
+    tracing::Span span;
+  };
+
+  /// Add a task to the scheduler
+  ///
+  /// If the scheduler is in an aborted state this call will return false and the task
+  /// will never be run.  This is harmless and does not need to be guarded against.
+  ///
+  /// The return value for this call can usually be ignored.  There is little harm in
+  /// attempting to add tasks to an aborted scheduler.  It is only included for callers
+  /// that want to avoid future task generation to save effort.
+  ///
+  /// \param task the task to submit
+  ///
+  /// A task's name must remain valid for the duration of the task.  It is used for
+  /// debugging (e.g. when debugging a deadlock to see which tasks still remain) and for
+  /// traceability (the name will be used for spans assigned to the task)
+  ///
+  /// \return true if the task was submitted or queued, false if the task was ignored
+  virtual bool AddTask(std::unique_ptr<Task> task) = 0;
+
+  /// Adds an async generator to the scheduler
+  ///
+  /// The async generator will be visited, one item at a time.  Submitting a task
+  /// will consist of polling the generator for the next future.  The generator's future
+  /// will then represent the task itself.
+  ///
+  /// This visits the task serially without readahead.  If readahead or parallelism
+  /// is desired then it should be added in the generator itself.
+  ///
+  /// The generator itself will be kept alive until all tasks have been completed.
+  /// However, if the scheduler is aborted, the generator will be destroyed as soon as the
+  /// next item would be requested.
+  ///
+  /// \param generator the generator to submit to the scheduler
+  /// \param visitor a function which visits each generator future as it completes
+  /// \param name a name which will be used for each submitted task
+  template <typename T>
+  bool AddAsyncGenerator(std::function<Future<T>()> generator,
+                         std::function<Status(const T&)> visitor, std::string_view name);
+
+  template <typename Callable>
+  struct SimpleTask : public Task {
+    SimpleTask(Callable callable, std::string_view name)
+        : callable(std::move(callable)), name_(name) {}
+    SimpleTask(Callable callable, std::string name)
+        : callable(std::move(callable)), owned_name_(std::move(name)) {
+      name_ = *owned_name_;
+    }
+    Result<Future<>> operator()() override { return callable(); }
+    std::string_view name() const override { return name_; }
+    Callable callable;
+    std::string_view name_;
+    std::optional<std::string> owned_name_;
+  };
+
+  /// Add a task with cost 1 to the scheduler
+  ///
+  /// \param callable a "submit" function that should return a future
+  /// \param name a name for the task
+  ///
+  /// `name` must remain valid until the task has been submitted AND the returned
+  /// future completes.  It is used for debugging and tracing.
+  ///
+  /// \see AddTask for more details
+  template <typename Callable>
+  bool AddSimpleTask(Callable callable, std::string_view name) {
+    return AddTask(std::make_unique<SimpleTask<Callable>>(std::move(callable), name));
+  }
+
+  /// Add a task with cost 1 to the scheduler
+  ///
+  /// This is an overload of \see AddSimpleTask that keeps `name` alive
+  /// in the task.
+  template <typename Callable>
+  bool AddSimpleTask(Callable callable, std::string name) {
+    return AddTask(
+        std::make_unique<SimpleTask<Callable>>(std::move(callable), std::move(name)));
+  }
+
+  /// Construct a scheduler
+  ///
+  /// \param initial_task The initial task which is responsible for adding
+  ///        the first subtasks to the scheduler.
+  /// \param abort_callback A callback that will be triggered immediately after a task
+  ///        fails while other tasks may still be running.  Nothing needs to be done here,
+  ///        when a task fails the scheduler will stop accepting new tasks and eventually
+  ///        return the error.  However, this callback can be used to more quickly end
+  ///        long running tasks that have already been submitted.  Defaults to doing
+  ///        nothing.
+  /// \param stop_token An optional stop token that will allow cancellation of the
+  ///        scheduler.  This will be checked before each task is submitted and, in the
+  ///        event of a cancellation, the scheduler will enter an aborted state. This is
+  ///        a graceful cancellation and submitted tasks will still complete.
+  /// \return A future that will be completed when the initial task and all subtasks have
+  ///         finished.
+  static Future<> Make(
+      FnOnce<Status(AsyncTaskScheduler*)> initial_task,
+      FnOnce<void(const Status&)> abort_callback = [](const Status&) {},
+      StopToken stop_token = StopToken::Unstoppable());
+
+  /// A span tracking execution of the scheduler's tasks, for internal use only
+  virtual const tracing::Span& span() const = 0;
+};
+
+class ARROW_EXPORT ThrottledAsyncTaskScheduler : public AsyncTaskScheduler {
+ public:
+  /// An interface for a task queue
+  ///
+  /// A queue's methods will not be called concurrently
+  class Queue {
+   public:
+    virtual ~Queue() = default;
+    /// Push a task to the queue
+    ///
+    /// \param task the task to enqueue
+    virtual void Push(std::unique_ptr<Task> task) = 0;
+    /// Pop the next task from the queue
+    virtual std::unique_ptr<Task> Pop() = 0;
+    /// Peek the next task in the queue
+    virtual const Task& Peek() = 0;
+    /// Check if the queue is empty
+    virtual bool Empty() = 0;
+    /// Purge the queue of all items
+    virtual void Purge() = 0;
+    virtual std::size_t Size() const = 0;
+  };
+
+  class Throttle {
+   public:
+    virtual ~Throttle() = default;
+    /// Acquire amt permits
+    ///
+    /// If nullopt is returned then the permits were immediately
+    /// acquired and the caller can proceed.  If a future is returned then the caller
+    /// should wait for the future to complete first.  When the returned future completes
+    /// the permits have NOT been acquired and the caller must call Acquire again
+    ///
+    /// \param amt the number of permits to acquire
+    virtual std::optional<Future<>> TryAcquire(int amt) = 0;
+    /// Release amt permits
+    ///
+    /// This will possibly complete waiting futures and should probably not be
+    /// called while holding locks.
+    ///
+    /// \param amt the number of permits to release
+    virtual void Release(int amt) = 0;
+
+    /// The size of the largest task that can run
+    ///
+    /// Incoming tasks will have their cost latched to this value to ensure
+    /// they can still run (although they will be the only thing allowed to
+    /// run at that time).
+    virtual int Capacity() = 0;
+
+    /// Pause the throttle
+    ///
+    /// Any tasks that have been submitted already will continue.  However, no new tasks
+    /// will be run until the throttle is resumed.
+    virtual void Pause() = 0;
+    /// Resume the throttle
+    ///
+    /// Allows task to be submitted again.  If there is a max_concurrent_cost limit then
+    /// it will still apply.
+    virtual void Resume() = 0;
+  };
+
+  /// Pause the throttle
+  ///
+  /// Any tasks that have been submitted already will continue.  However, no new tasks
+  /// will be run until the throttle is resumed.
+  virtual void Pause() = 0;
+  /// Resume the throttle
+  ///
+  /// Allows task to be submitted again.  If there is a max_concurrent_cost limit then
+  /// it will still apply.
+  virtual void Resume() = 0;
+  /// Return the number of tasks queued but not yet submitted
+  virtual std::size_t QueueSize() = 0;
+
+  /// Create a throttled view of a scheduler
+  ///
+  /// Tasks added via this view will be subjected to the throttle and, if the tasks cannot
+  /// run immediately, will be placed into a queue.
+  ///
+  /// Although a shared_ptr is returned it should generally be assumed that the caller
+  /// is being given exclusive ownership.  The shared_ptr is used to share the view with
+  /// queued and submitted tasks and the lifetime of those is unpredictable.  It is
+  /// important the caller keep the returned pointer alive for as long as they plan to add
+  /// tasks to the view.
+  ///
+  /// \param scheduler a scheduler to submit tasks to after throttling
+  ///
+  /// This can be the root scheduler, another throttled scheduler, or a task group.  These
+  /// are all composable.
+  ///
+  /// \param max_concurrent_cost the maximum amount of cost allowed to run at any one time
+  ///
+  /// If a task is added that has a cost greater than max_concurrent_cost then its cost
+  /// will be reduced to max_concurrent_cost so that it is still possible for the task to
+  /// run.
+  ///
+  /// \param queue the queue to use when tasks cannot be submitted
+  ///
+  /// By default a FIFO queue will be used.  However, a custom queue can be provided if
+  /// some tasks have higher priority than other tasks.
+  static std::shared_ptr<ThrottledAsyncTaskScheduler> Make(
+      AsyncTaskScheduler* scheduler, int max_concurrent_cost,
+      std::unique_ptr<Queue> queue = NULLPTR);
+
+  /// @brief Create a ThrottledAsyncTaskScheduler using a custom throttle
+  ///
+  /// \see Make
+  static std::shared_ptr<ThrottledAsyncTaskScheduler> MakeWithCustomThrottle(
+      AsyncTaskScheduler* scheduler, std::unique_ptr<Throttle> throttle,
+      std::unique_ptr<Queue> queue = NULLPTR);
+};
+
+/// A utility to keep track of a collection of tasks
+///
+/// Often it is useful to keep track of some state that only needs to stay alive
+/// for some small collection of tasks, or to perform some kind of final cleanup
+/// when a collection of tasks is finished.
+///
+/// For example, when scanning, we need to keep the file reader alive while all scan
+/// tasks run for a given file, and then we can gracefully close it when we finish the
+/// file.
+class ARROW_EXPORT AsyncTaskGroup : public AsyncTaskScheduler {
+ public:
+  /// Destructor for the task group
+  ///
+  /// The destructor might trigger the finish callback.  If the finish callback fails
+  /// then the error will be reported as a task on the scheduler.
+  ///
+  /// Failure to destroy the async task group will not prevent the scheduler from
+  /// finishing.  If the scheduler finishes before the async task group is done then
+  /// the finish callback will be run immediately when the async task group finishes.
+  ///
+  /// If the scheduler has aborted then the finish callback will not run.
+  ~AsyncTaskGroup() = default;
+  /// Create an async task group
+  ///
+  /// The finish callback will not run until the task group is destroyed and all
+  /// tasks are finished so you will generally want to reset / destroy the returned
+  /// unique_ptr at some point.
+  ///
+  /// \param scheduler The underlying scheduler to submit tasks to
+  /// \param finish_callback A callback that will be run only after the task group has
+  ///                        been destroyed and all tasks added by the group have
+  ///                        finished.
+  ///
+  /// Note: in error scenarios the finish callback may not run.  However, it will still,
+  /// of course, be destroyed.
+  static std::unique_ptr<AsyncTaskGroup> Make(AsyncTaskScheduler* scheduler,
+                                              FnOnce<Status()> finish_callback);
+};
+
+/// Create a task group that is also throttled
+///
+/// This is a utility factory that creates a throttled view of a scheduler and then
+/// wraps that throttled view with a task group that destroys the throttle when finished.
+///
+/// \see ThrottledAsyncTaskScheduler
+/// \see AsyncTaskGroup
+/// \param target the underlying scheduler to submit tasks to
+/// \param max_concurrent_cost the maximum amount of cost allowed to run at any one time
+/// \param queue the queue to use when tasks cannot be submitted
+/// \param finish_callback A callback that will be run only after the task group has
+///                  been destroyed and all tasks added by the group have finished
+ARROW_EXPORT std::unique_ptr<ThrottledAsyncTaskScheduler> MakeThrottledAsyncTaskGroup(
+    AsyncTaskScheduler* target, int max_concurrent_cost,
+    std::unique_ptr<ThrottledAsyncTaskScheduler::Queue> queue,
+    FnOnce<Status()> finish_callback);
+
+// Defined down here to avoid circular dependency between AsyncTaskScheduler and
+// AsyncTaskGroup
+template <typename T>
+bool AsyncTaskScheduler::AddAsyncGenerator(std::function<Future<T>()> generator,
+                                           std::function<Status(const T&)> visitor,
+                                           std::string_view name) {
+  struct State {
+    State(std::function<Future<T>()> generator, std::function<Status(const T&)> visitor,
+          std::unique_ptr<AsyncTaskGroup> task_group, std::string_view name)
+        : generator(std::move(generator)),
+          visitor(std::move(visitor)),
+          task_group(std::move(task_group)),
+          name(name) {}
+    std::function<Future<T>()> generator;
+    std::function<Status(const T&)> visitor;
+    std::unique_ptr<AsyncTaskGroup> task_group;
+    std::string_view name;
+  };
+  struct SubmitTask : public Task {
+    explicit SubmitTask(std::unique_ptr<State> state_holder)
+        : state_holder(std::move(state_holder)) {}
+
+    struct SubmitTaskCallback {
+      SubmitTaskCallback(std::unique_ptr<State> state_holder, Future<> task_completion)
+          : state_holder(std::move(state_holder)),
+            task_completion(std::move(task_completion)) {}
+      void operator()(const Result<T>& maybe_item) {
+        if (!maybe_item.ok()) {
+          task_completion.MarkFinished(maybe_item.status());
+          return;
+        }
+        const auto& item = *maybe_item;
+        if (IsIterationEnd(item)) {
+          task_completion.MarkFinished();
+          return;
+        }
+        Status visit_st = state_holder->visitor(item);
+        if (!visit_st.ok()) {
+          task_completion.MarkFinished(std::move(visit_st));
+          return;
+        }
+        state_holder->task_group->AddTask(
+            std::make_unique<SubmitTask>(std::move(state_holder)));
+        task_completion.MarkFinished();
+      }
+      std::unique_ptr<State> state_holder;
+      Future<> task_completion;
+    };
+
+    Result<Future<>> operator()() {
+      Future<> task = Future<>::Make();
+      // Consume as many items as we can (those that are already finished)
+      // synchronously to avoid recursion / stack overflow.
+      while (true) {
+        Future<T> next = state_holder->generator();
+        if (next.TryAddCallback(
+                [&] { return SubmitTaskCallback(std::move(state_holder), task); })) {
+          return task;
+        }
+        ARROW_ASSIGN_OR_RAISE(T item, next.result());
+        if (IsIterationEnd(item)) {
+          task.MarkFinished();
+          return task;
+        }
+        ARROW_RETURN_NOT_OK(state_holder->visitor(item));
+      }
+    }
+
+    std::string_view name() const { return state_holder->name; }
+
+    std::unique_ptr<State> state_holder;
+  };
+  std::unique_ptr<AsyncTaskGroup> task_group =
+      AsyncTaskGroup::Make(this, [] { return Status::OK(); });
+  AsyncTaskGroup* task_group_view = task_group.get();
+  std::unique_ptr<State> state_holder = std::make_unique<State>(
+      std::move(generator), std::move(visitor), std::move(task_group), name);
+  task_group_view->AddTask(std::make_unique<SubmitTask>(std::move(state_holder)));
+  return true;
+}
+
+}  // namespace util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/basic_decimal.h

@@ -0,0 +1,492 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <array>
+#include <cstdint>
+#include <cstring>
+#include <limits>
+#include <string>
+#include <type_traits>
+
+#include "arrow/util/endian.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/type_traits.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+
+enum class DecimalStatus {
+  kSuccess,
+  kDivideByZero,
+  kOverflow,
+  kRescaleDataLoss,
+};
+
+template <typename Derived, int BIT_WIDTH, int NWORDS = BIT_WIDTH / 64>
+class ARROW_EXPORT GenericBasicDecimal {
+ protected:
+  struct LittleEndianArrayTag {};
+
+#if ARROW_LITTLE_ENDIAN
+  static constexpr int kHighWordIndex = NWORDS - 1;
+  static constexpr int kLowWordIndex = 0;
+#else
+  static constexpr int kHighWordIndex = 0;
+  static constexpr int kLowWordIndex = NWORDS - 1;
+#endif
+
+ public:
+  static constexpr int kBitWidth = BIT_WIDTH;
+  static constexpr int kByteWidth = kBitWidth / 8;
+  static constexpr int kNumWords = NWORDS;
+
+  // A constructor tag to introduce a little-endian encoded array
+  static constexpr LittleEndianArrayTag LittleEndianArray{};
+
+  using WordArray = std::array<uint64_t, NWORDS>;
+
+  /// \brief Empty constructor creates a decimal with a value of 0.
+  constexpr GenericBasicDecimal() noexcept : array_({0}) {}
+
+  /// \brief Create a decimal from the two's complement representation.
+  ///
+  /// Input array is assumed to be in native endianness.
+  explicit constexpr GenericBasicDecimal(const WordArray& array) noexcept
+      : array_(array) {}
+
+  /// \brief Create a decimal from the two's complement representation.
+  ///
+  /// Input array is assumed to be in little endianness, with native endian elements.
+  GenericBasicDecimal(LittleEndianArrayTag, const WordArray& array) noexcept
+      : GenericBasicDecimal(bit_util::little_endian::ToNative(array)) {}
+
+  /// \brief Create a decimal from any integer not wider than 64 bits.
+  template <typename T,
+            typename = typename std::enable_if<
+                std::is_integral<T>::value && (sizeof(T) <= sizeof(uint64_t)), T>::type>
+  constexpr GenericBasicDecimal(T value) noexcept  // NOLINT(runtime/explicit)
+      : array_(WordsFromLowBits(value)) {}
+
+  /// \brief Create a decimal from an array of bytes.
+  ///
+  /// Bytes are assumed to be in native-endian byte order.
+  explicit GenericBasicDecimal(const uint8_t* bytes) {
+    memcpy(array_.data(), bytes, sizeof(array_));
+  }
+
+  /// \brief Get the bits of the two's complement representation of the number.
+  ///
+  /// The elements are in native endian order. The bits within each uint64_t element
+  /// are in native endian order. For example, on a little endian machine,
+  /// BasicDecimal128(123).native_endian_array() = {123, 0};
+  /// but on a big endian machine,
+  /// BasicDecimal128(123).native_endian_array() = {0, 123};
+  constexpr const WordArray& native_endian_array() const { return array_; }
+
+  /// \brief Get the bits of the two's complement representation of the number.
+  ///
+  /// The elements are in little endian order. However, the bits within each
+  /// uint64_t element are in native endian order.
+  /// For example, BasicDecimal128(123).little_endian_array() = {123, 0};
+  WordArray little_endian_array() const {
+    return bit_util::little_endian::FromNative(array_);
+  }
+
+  const uint8_t* native_endian_bytes() const {
+    return reinterpret_cast<const uint8_t*>(array_.data());
+  }
+
+  uint8_t* mutable_native_endian_bytes() {
+    return reinterpret_cast<uint8_t*>(array_.data());
+  }
+
+  /// \brief Return the raw bytes of the value in native-endian byte order.
+  std::array<uint8_t, kByteWidth> ToBytes() const {
+    std::array<uint8_t, kByteWidth> out{{0}};
+    memcpy(out.data(), array_.data(), kByteWidth);
+    return out;
+  }
+
+  /// \brief Copy the raw bytes of the value in native-endian byte order.
+  void ToBytes(uint8_t* out) const { memcpy(out, array_.data(), kByteWidth); }
+
+  /// Return 1 if positive or zero, -1 if strictly negative.
+  int64_t Sign() const {
+    return 1 | (static_cast<int64_t>(array_[kHighWordIndex]) >> 63);
+  }
+
+  bool IsNegative() const { return static_cast<int64_t>(array_[kHighWordIndex]) < 0; }
+
+  explicit operator bool() const { return array_ != WordArray{}; }
+
+  friend bool operator==(const GenericBasicDecimal& left,
+                         const GenericBasicDecimal& right) {
+    return left.array_ == right.array_;
+  }
+
+  friend bool operator!=(const GenericBasicDecimal& left,
+                         const GenericBasicDecimal& right) {
+    return left.array_ != right.array_;
+  }
+
+ protected:
+  WordArray array_;
+
+  template <typename T>
+  static constexpr uint64_t SignExtend(T low_bits) noexcept {
+    return low_bits >= T{} ? uint64_t{0} : ~uint64_t{0};
+  }
+
+  template <typename T>
+  static constexpr WordArray WordsFromLowBits(T low_bits) {
+    WordArray words{};
+    if (low_bits < T{}) {
+      for (auto& word : words) {
+        word = ~uint64_t{0};
+      }
+    }
+    words[kLowWordIndex] = static_cast<uint64_t>(low_bits);
+    return words;
+  }
+};
+
+/// Represents a signed 128-bit integer in two's complement.
+///
+/// This class is also compiled into LLVM IR - so, it should not have cpp references like
+/// streams and boost.
+class ARROW_EXPORT BasicDecimal128 : public GenericBasicDecimal<BasicDecimal128, 128> {
+ public:
+  static constexpr int kMaxPrecision = 38;
+  static constexpr int kMaxScale = 38;
+
+  using GenericBasicDecimal::GenericBasicDecimal;
+
+  constexpr BasicDecimal128() noexcept : GenericBasicDecimal() {}
+
+  /// \brief Create a BasicDecimal128 from the two's complement representation.
+#if ARROW_LITTLE_ENDIAN
+  constexpr BasicDecimal128(int64_t high, uint64_t low) noexcept
+      : BasicDecimal128(WordArray{low, static_cast<uint64_t>(high)}) {}
+#else
+  constexpr BasicDecimal128(int64_t high, uint64_t low) noexcept
+      : BasicDecimal128(WordArray{static_cast<uint64_t>(high), low}) {}
+#endif
+
+  /// \brief Negate the current value (in-place)
+  BasicDecimal128& Negate();
+
+  /// \brief Absolute value (in-place)
+  BasicDecimal128& Abs();
+
+  /// \brief Absolute value
+  static BasicDecimal128 Abs(const BasicDecimal128& left);
+
+  /// \brief Add a number to this one. The result is truncated to 128 bits.
+  BasicDecimal128& operator+=(const BasicDecimal128& right);
+
+  /// \brief Subtract a number from this one. The result is truncated to 128 bits.
+  BasicDecimal128& operator-=(const BasicDecimal128& right);
+
+  /// \brief Multiply this number by another number. The result is truncated to 128 bits.
+  BasicDecimal128& operator*=(const BasicDecimal128& right);
+
+  /// Divide this number by right and return the result.
+  ///
+  /// This operation is not destructive.
+  /// The answer rounds to zero. Signs work like:
+  ///   21 /  5 ->  4,  1
+  ///  -21 /  5 -> -4, -1
+  ///   21 / -5 -> -4,  1
+  ///  -21 / -5 ->  4, -1
+  /// \param[in] divisor the number to divide by
+  /// \param[out] result the quotient
+  /// \param[out] remainder the remainder after the division
+  DecimalStatus Divide(const BasicDecimal128& divisor, BasicDecimal128* result,
+                       BasicDecimal128* remainder) const;
+
+  /// \brief In-place division.
+  BasicDecimal128& operator/=(const BasicDecimal128& right);
+
+  /// \brief Bitwise "or" between two BasicDecimal128.
+  BasicDecimal128& operator|=(const BasicDecimal128& right);
+
+  /// \brief Bitwise "and" between two BasicDecimal128.
+  BasicDecimal128& operator&=(const BasicDecimal128& right);
+
+  /// \brief Shift left by the given number of bits.
+  BasicDecimal128& operator<<=(uint32_t bits);
+
+  BasicDecimal128 operator<<(uint32_t bits) const {
+    auto res = *this;
+    res <<= bits;
+    return res;
+  }
+
+  /// \brief Shift right by the given number of bits.
+  ///
+  /// Negative values will sign-extend.
+  BasicDecimal128& operator>>=(uint32_t bits);
+
+  BasicDecimal128 operator>>(uint32_t bits) const {
+    auto res = *this;
+    res >>= bits;
+    return res;
+  }
+
+  /// \brief Get the high bits of the two's complement representation of the number.
+  constexpr int64_t high_bits() const {
+#if ARROW_LITTLE_ENDIAN
+    return static_cast<int64_t>(array_[1]);
+#else
+    return static_cast<int64_t>(array_[0]);
+#endif
+  }
+
+  /// \brief Get the low bits of the two's complement representation of the number.
+  constexpr uint64_t low_bits() const {
+#if ARROW_LITTLE_ENDIAN
+    return array_[0];
+#else
+    return array_[1];
+#endif
+  }
+
+  /// \brief separate the integer and fractional parts for the given scale.
+  void GetWholeAndFraction(int32_t scale, BasicDecimal128* whole,
+                           BasicDecimal128* fraction) const;
+
+  /// \brief Scale multiplier for given scale value.
+  static const BasicDecimal128& GetScaleMultiplier(int32_t scale);
+  /// \brief Half-scale multiplier for given scale value.
+  static const BasicDecimal128& GetHalfScaleMultiplier(int32_t scale);
+
+  /// \brief Convert BasicDecimal128 from one scale to another
+  DecimalStatus Rescale(int32_t original_scale, int32_t new_scale,
+                        BasicDecimal128* out) const;
+
+  /// \brief Scale up.
+  BasicDecimal128 IncreaseScaleBy(int32_t increase_by) const;
+
+  /// \brief Scale down.
+  /// - If 'round' is true, the right-most digits are dropped and the result value is
+  ///   rounded up (+1 for +ve, -1 for -ve) based on the value of the dropped digits
+  ///   (>= 10^reduce_by / 2).
+  /// - If 'round' is false, the right-most digits are simply dropped.
+  BasicDecimal128 ReduceScaleBy(int32_t reduce_by, bool round = true) const;
+
+  /// \brief Whether this number fits in the given precision
+  ///
+  /// Return true if the number of significant digits is less or equal to `precision`.
+  bool FitsInPrecision(int32_t precision) const;
+
+  /// \brief count the number of leading binary zeroes.
+  int32_t CountLeadingBinaryZeros() const;
+
+  /// \brief Get the maximum valid unscaled decimal value.
+  static const BasicDecimal128& GetMaxValue();
+
+  /// \brief Get the maximum valid unscaled decimal value for the given precision.
+  static BasicDecimal128 GetMaxValue(int32_t precision);
+
+  /// \brief Get the maximum decimal value (is not a valid value).
+  static constexpr BasicDecimal128 GetMaxSentinel() {
+    return BasicDecimal128(/*high=*/std::numeric_limits<int64_t>::max(),
+                           /*low=*/std::numeric_limits<uint64_t>::max());
+  }
+  /// \brief Get the minimum decimal value (is not a valid value).
+  static constexpr BasicDecimal128 GetMinSentinel() {
+    return BasicDecimal128(/*high=*/std::numeric_limits<int64_t>::min(),
+                           /*low=*/std::numeric_limits<uint64_t>::min());
+  }
+};
+
+ARROW_EXPORT bool operator<(const BasicDecimal128& left, const BasicDecimal128& right);
+ARROW_EXPORT bool operator<=(const BasicDecimal128& left, const BasicDecimal128& right);
+ARROW_EXPORT bool operator>(const BasicDecimal128& left, const BasicDecimal128& right);
+ARROW_EXPORT bool operator>=(const BasicDecimal128& left, const BasicDecimal128& right);
+
+ARROW_EXPORT BasicDecimal128 operator-(const BasicDecimal128& operand);
+ARROW_EXPORT BasicDecimal128 operator~(const BasicDecimal128& operand);
+ARROW_EXPORT BasicDecimal128 operator+(const BasicDecimal128& left,
+                                       const BasicDecimal128& right);
+ARROW_EXPORT BasicDecimal128 operator-(const BasicDecimal128& left,
+                                       const BasicDecimal128& right);
+ARROW_EXPORT BasicDecimal128 operator*(const BasicDecimal128& left,
+                                       const BasicDecimal128& right);
+ARROW_EXPORT BasicDecimal128 operator/(const BasicDecimal128& left,
+                                       const BasicDecimal128& right);
+ARROW_EXPORT BasicDecimal128 operator%(const BasicDecimal128& left,
+                                       const BasicDecimal128& right);
+
+class ARROW_EXPORT BasicDecimal256 : public GenericBasicDecimal<BasicDecimal256, 256> {
+ public:
+  using GenericBasicDecimal::GenericBasicDecimal;
+
+  static constexpr int kMaxPrecision = 76;
+  static constexpr int kMaxScale = 76;
+
+  constexpr BasicDecimal256() noexcept : GenericBasicDecimal() {}
+
+  explicit BasicDecimal256(const BasicDecimal128& value) noexcept
+      : BasicDecimal256(bit_util::little_endian::ToNative<uint64_t, 4>(
+            {value.low_bits(), static_cast<uint64_t>(value.high_bits()),
+             SignExtend(value.high_bits()), SignExtend(value.high_bits())})) {}
+
+  /// \brief Negate the current value (in-place)
+  BasicDecimal256& Negate();
+
+  /// \brief Absolute value (in-place)
+  BasicDecimal256& Abs();
+
+  /// \brief Absolute value
+  static BasicDecimal256 Abs(const BasicDecimal256& left);
+
+  /// \brief Add a number to this one. The result is truncated to 256 bits.
+  BasicDecimal256& operator+=(const BasicDecimal256& right);
+
+  /// \brief Subtract a number from this one. The result is truncated to 256 bits.
+  BasicDecimal256& operator-=(const BasicDecimal256& right);
+
+  /// \brief Get the lowest bits of the two's complement representation of the number.
+  uint64_t low_bits() const { return bit_util::little_endian::Make(array_)[0]; }
+
+  /// \brief separate the integer and fractional parts for the given scale.
+  void GetWholeAndFraction(int32_t scale, BasicDecimal256* whole,
+                           BasicDecimal256* fraction) const;
+
+  /// \brief Scale multiplier for given scale value.
+  static const BasicDecimal256& GetScaleMultiplier(int32_t scale);
+  /// \brief Half-scale multiplier for given scale value.
+  static const BasicDecimal256& GetHalfScaleMultiplier(int32_t scale);
+
+  /// \brief Convert BasicDecimal256 from one scale to another
+  DecimalStatus Rescale(int32_t original_scale, int32_t new_scale,
+                        BasicDecimal256* out) const;
+
+  /// \brief Scale up.
+  BasicDecimal256 IncreaseScaleBy(int32_t increase_by) const;
+
+  /// \brief Scale down.
+  /// - If 'round' is true, the right-most digits are dropped and the result value is
+  ///   rounded up (+1 for positive, -1 for negative) based on the value of the
+  ///   dropped digits (>= 10^reduce_by / 2).
+  /// - If 'round' is false, the right-most digits are simply dropped.
+  BasicDecimal256 ReduceScaleBy(int32_t reduce_by, bool round = true) const;
+
+  /// \brief Whether this number fits in the given precision
+  ///
+  /// Return true if the number of significant digits is less or equal to `precision`.
+  bool FitsInPrecision(int32_t precision) const;
+
+  /// \brief Multiply this number by another number. The result is truncated to 256 bits.
+  BasicDecimal256& operator*=(const BasicDecimal256& right);
+
+  /// Divide this number by right and return the result.
+  ///
+  /// This operation is not destructive.
+  /// The answer rounds to zero. Signs work like:
+  ///   21 /  5 ->  4,  1
+  ///  -21 /  5 -> -4, -1
+  ///   21 / -5 -> -4,  1
+  ///  -21 / -5 ->  4, -1
+  /// \param[in] divisor the number to divide by
+  /// \param[out] result the quotient
+  /// \param[out] remainder the remainder after the division
+  DecimalStatus Divide(const BasicDecimal256& divisor, BasicDecimal256* result,
+                       BasicDecimal256* remainder) const;
+
+  /// \brief Shift left by the given number of bits.
+  BasicDecimal256& operator<<=(uint32_t bits);
+
+  BasicDecimal256 operator<<(uint32_t bits) const {
+    auto res = *this;
+    res <<= bits;
+    return res;
+  }
+
+  /// \brief Shift right by the given number of bits.
+  ///
+  /// Negative values will sign-extend.
+  BasicDecimal256& operator>>=(uint32_t bits);
+
+  BasicDecimal256 operator>>(uint32_t bits) const {
+    auto res = *this;
+    res >>= bits;
+    return res;
+  }
+
+  /// \brief In-place division.
+  BasicDecimal256& operator/=(const BasicDecimal256& right);
+
+  /// \brief Get the maximum valid unscaled decimal value for the given precision.
+  static BasicDecimal256 GetMaxValue(int32_t precision);
+
+  /// \brief Get the maximum decimal value (is not a valid value).
+  static constexpr BasicDecimal256 GetMaxSentinel() {
+#if ARROW_LITTLE_ENDIAN
+    return BasicDecimal256({std::numeric_limits<uint64_t>::max(),
+                            std::numeric_limits<uint64_t>::max(),
+                            std::numeric_limits<uint64_t>::max(),
+                            static_cast<uint64_t>(std::numeric_limits<int64_t>::max())});
+#else
+    return BasicDecimal256({static_cast<uint64_t>(std::numeric_limits<int64_t>::max()),
+                            std::numeric_limits<uint64_t>::max(),
+                            std::numeric_limits<uint64_t>::max(),
+                            std::numeric_limits<uint64_t>::max()});
+#endif
+  }
+  /// \brief Get the minimum decimal value (is not a valid value).
+  static constexpr BasicDecimal256 GetMinSentinel() {
+#if ARROW_LITTLE_ENDIAN
+    return BasicDecimal256(
+        {0, 0, 0, static_cast<uint64_t>(std::numeric_limits<int64_t>::min())});
+#else
+    return BasicDecimal256(
+        {static_cast<uint64_t>(std::numeric_limits<int64_t>::min()), 0, 0, 0});
+#endif
+  }
+};
+
+ARROW_EXPORT bool operator<(const BasicDecimal256& left, const BasicDecimal256& right);
+
+ARROW_EXPORT inline bool operator<=(const BasicDecimal256& left,
+                                    const BasicDecimal256& right) {
+  return !operator<(right, left);
+}
+
+ARROW_EXPORT inline bool operator>(const BasicDecimal256& left,
+                                   const BasicDecimal256& right) {
+  return operator<(right, left);
+}
+
+ARROW_EXPORT inline bool operator>=(const BasicDecimal256& left,
+                                    const BasicDecimal256& right) {
+  return !operator<(left, right);
+}
+
+ARROW_EXPORT BasicDecimal256 operator-(const BasicDecimal256& operand);
+ARROW_EXPORT BasicDecimal256 operator~(const BasicDecimal256& operand);
+ARROW_EXPORT BasicDecimal256 operator+(const BasicDecimal256& left,
+                                       const BasicDecimal256& right);
+ARROW_EXPORT BasicDecimal256 operator*(const BasicDecimal256& left,
+                                       const BasicDecimal256& right);
+ARROW_EXPORT BasicDecimal256 operator/(const BasicDecimal256& left,
+                                       const BasicDecimal256& right);
+
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/benchmark_util.h

@@ -0,0 +1,211 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include <algorithm>
+#include <cstdint>
+#include <string>
+
+#include "benchmark/benchmark.h"
+
+#include "arrow/memory_pool.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/cpu_info.h"
+#include "arrow/util/logging.h"  // IWYU pragma: keep
+
+namespace arrow {
+
+// Benchmark changed its parameter type between releases from
+// int to int64_t. As it doesn't have version macros, we need
+// to apply C++ template magic.
+
+template <typename Func>
+struct BenchmarkArgsType;
+
+// Pattern matching that extracts the vector element type of Benchmark::Args()
+template <typename Values>
+struct BenchmarkArgsType<benchmark::internal::Benchmark* (
+    benchmark::internal::Benchmark::*)(const std::vector<Values>&)> {
+  using type = Values;
+};
+
+using ArgsType =
+    typename BenchmarkArgsType<decltype(&benchmark::internal::Benchmark::Args)>::type;
+
+using internal::CpuInfo;
+
+static const CpuInfo* cpu_info = CpuInfo::GetInstance();
+
+static const int64_t kL1Size = cpu_info->CacheSize(CpuInfo::CacheLevel::L1);
+static const int64_t kL2Size = cpu_info->CacheSize(CpuInfo::CacheLevel::L2);
+static const int64_t kL3Size = cpu_info->CacheSize(CpuInfo::CacheLevel::L3);
+static const int64_t kCantFitInL3Size = kL3Size * 4;
+static const std::vector<int64_t> kMemorySizes = {kL1Size, kL2Size, kL3Size,
+                                                  kCantFitInL3Size};
+// 0 is treated as "no nulls"
+static const std::vector<ArgsType> kInverseNullProportions = {10000, 100, 10, 2, 1, 0};
+
+struct GenericItemsArgs {
+  // number of items processed per iteration
+  const int64_t size;
+
+  // proportion of nulls in generated arrays
+  double null_proportion;
+
+  explicit GenericItemsArgs(benchmark::State& state)
+      : size(state.range(0)), state_(state) {
+    if (state.range(1) == 0) {
+      this->null_proportion = 0.0;
+    } else {
+      this->null_proportion = std::min(1., 1. / static_cast<double>(state.range(1)));
+    }
+  }
+
+  ~GenericItemsArgs() {
+    state_.counters["size"] = static_cast<double>(size);
+    state_.counters["null_percent"] = null_proportion * 100;
+    state_.SetItemsProcessed(state_.iterations() * size);
+  }
+
+ private:
+  benchmark::State& state_;
+};
+
+void BenchmarkSetArgsWithSizes(benchmark::internal::Benchmark* bench,
+                               const std::vector<int64_t>& sizes = kMemorySizes) {
+  bench->Unit(benchmark::kMicrosecond);
+
+  for (const auto size : sizes) {
+    for (const auto inverse_null_proportion : kInverseNullProportions) {
+      bench->Args({static_cast<ArgsType>(size), inverse_null_proportion});
+    }
+  }
+}
+
+void BenchmarkSetArgs(benchmark::internal::Benchmark* bench) {
+  BenchmarkSetArgsWithSizes(bench, kMemorySizes);
+}
+
+void RegressionSetArgs(benchmark::internal::Benchmark* bench) {
+  // Regression do not need to account for cache hierarchy, thus optimize for
+  // the best case.
+  BenchmarkSetArgsWithSizes(bench, {kL1Size});
+}
+
+// RAII struct to handle some of the boilerplate in regression benchmarks
+struct RegressionArgs {
+  // size of memory tested (per iteration) in bytes
+  int64_t size;
+
+  // proportion of nulls in generated arrays
+  double null_proportion;
+
+  // If size_is_bytes is true, then it's a number of bytes, otherwise it's the
+  // number of items processed (for reporting)
+  explicit RegressionArgs(benchmark::State& state, bool size_is_bytes = true)
+      : size(state.range(0)), state_(state), size_is_bytes_(size_is_bytes) {
+    if (state.range(1) == 0) {
+      this->null_proportion = 0.0;
+    } else {
+      this->null_proportion = std::min(1., 1. / static_cast<double>(state.range(1)));
+    }
+  }
+
+  ~RegressionArgs() {
+    state_.counters["size"] = static_cast<double>(size);
+    state_.counters["null_percent"] = null_proportion * 100;
+    if (size_is_bytes_) {
+      state_.SetBytesProcessed(state_.iterations() * size);
+    } else {
+      state_.SetItemsProcessed(state_.iterations() * size);
+    }
+  }
+
+ private:
+  benchmark::State& state_;
+  bool size_is_bytes_;
+};
+
+class MemoryPoolMemoryManager : public benchmark::MemoryManager {
+  void Start() override {
+    memory_pool = std::make_shared<ProxyMemoryPool>(default_memory_pool());
+
+    MemoryPool* default_pool = default_memory_pool();
+    global_allocations_start = default_pool->num_allocations();
+  }
+
+// BENCHMARK_DONT_OPTIMIZE is used here to detect Google Benchmark
+// 1.8.0. We can remove this Stop(Result*) when we require Google
+// Benchmark 1.8.0 or later.
+#ifndef BENCHMARK_DONT_OPTIMIZE
+  void Stop(Result* result) override { Stop(*result); }
+#endif
+
+  void Stop(benchmark::MemoryManager::Result& result) override {
+    // If num_allocations is still zero, we assume that the memory pool wasn't passed down
+    // so we should record them.
+    MemoryPool* default_pool = default_memory_pool();
+    int64_t new_default_allocations =
+        default_pool->num_allocations() - global_allocations_start;
+
+    // Only record metrics if (1) there were allocations and (2) we
+    // recorded at least one.
+    if (new_default_allocations > 0 && memory_pool->num_allocations() > 0) {
+      if (new_default_allocations > memory_pool->num_allocations()) {
+        // If we missed some, let's report that.
+        int64_t missed_allocations =
+            new_default_allocations - memory_pool->num_allocations();
+        ARROW_LOG(WARNING) << "BenchmarkMemoryTracker recorded some allocations "
+                           << "for a benchmark, but missed " << missed_allocations
+                           << " allocations.\n";
+      }
+
+      result.max_bytes_used = memory_pool->max_memory();
+      result.total_allocated_bytes = memory_pool->total_bytes_allocated();
+      result.num_allocs = memory_pool->num_allocations();
+    }
+  }
+
+ public:
+  std::shared_ptr<::arrow::ProxyMemoryPool> memory_pool;
+
+ protected:
+  int64_t global_allocations_start;
+};
+
+/// \brief Track memory pool allocations in benchmarks.
+///
+/// Instantiate as a global variable to register the hooks into Google Benchmark
+/// to collect memory metrics. Before each benchmark, a new ProxyMemoryPool is
+/// created. It can then be accessed with memory_pool(). Once the benchmark is
+/// complete, the hook will record the maximum memory used, the total bytes
+/// allocated, and the total number of allocations. If no allocations were seen,
+/// (for example, if you forgot to pass down the memory pool), then these metrics
+/// will not be saved.
+///
+/// Since this is used as one global variable, this will not work if multiple
+/// benchmarks are run concurrently or for multi-threaded benchmarks (ones
+/// that use `->ThreadRange(...)`).
+class BenchmarkMemoryTracker {
+ public:
+  BenchmarkMemoryTracker() : manager_() { ::benchmark::RegisterMemoryManager(&manager_); }
+  ::arrow::MemoryPool* memory_pool() const { return manager_.memory_pool.get(); }
+
+ protected:
+  ::arrow::MemoryPoolMemoryManager manager_;
+};
+
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/binary_view_util.h

@@ -0,0 +1,95 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <string_view>
+#include <utility>
+
+#include "arrow/type.h"
+#include "arrow/util/span.h"
+
+namespace arrow::util {
+
+inline BinaryViewType::c_type ToInlineBinaryView(const void* data, int32_t size) {
+  // Small string: inlined. Bytes beyond size are zeroed
+  BinaryViewType::c_type out;
+  out.inlined = {size, {}};
+  memcpy(&out.inlined.data, data, size);
+  return out;
+}
+
+inline BinaryViewType::c_type ToInlineBinaryView(std::string_view v) {
+  return ToInlineBinaryView(v.data(), static_cast<int32_t>(v.size()));
+}
+
+inline BinaryViewType::c_type ToBinaryView(const void* data, int32_t size,
+                                           int32_t buffer_index, int32_t offset) {
+  if (size <= BinaryViewType::kInlineSize) {
+    return ToInlineBinaryView(data, size);
+  }
+
+  // Large string: store index/offset.
+  BinaryViewType::c_type out;
+  out.ref = {size, {}, buffer_index, offset};
+  memcpy(&out.ref.prefix, data, sizeof(out.ref.prefix));
+  return out;
+}
+
+inline BinaryViewType::c_type ToBinaryView(std::string_view v, int32_t buffer_index,
+                                           int32_t offset) {
+  return ToBinaryView(v.data(), static_cast<int32_t>(v.size()), buffer_index, offset);
+}
+
+template <typename BufferPtr>
+std::string_view FromBinaryView(const BinaryViewType::c_type& v,
+                                const BufferPtr* data_buffers) {
+  auto* data = v.is_inline() ? v.inlined.data.data()
+                             : data_buffers[v.ref.buffer_index]->data() + v.ref.offset;
+  return {reinterpret_cast<const char*>(data), static_cast<size_t>(v.size())};
+}
+template <typename BufferPtr>
+std::string_view FromBinaryView(BinaryViewType::c_type&&, const BufferPtr*) = delete;
+
+template <typename BufferPtr>
+bool EqualBinaryView(BinaryViewType::c_type l, BinaryViewType::c_type r,
+                     const BufferPtr* l_buffers, const BufferPtr* r_buffers) {
+  int64_t l_size_and_prefix, r_size_and_prefix;
+  memcpy(&l_size_and_prefix, &l, sizeof(l_size_and_prefix));
+  memcpy(&r_size_and_prefix, &r, sizeof(r_size_and_prefix));
+
+  if (l_size_and_prefix != r_size_and_prefix) return false;
+
+  if (l.is_inline()) {
+    // The columnar spec mandates that the inlined part be zero-padded, so we can compare
+    // a word at a time regardless of the exact size.
+    int64_t l_inlined, r_inlined;
+    memcpy(&l_inlined, l.inline_data() + BinaryViewType::kPrefixSize, sizeof(l_inlined));
+    memcpy(&r_inlined, r.inline_data() + BinaryViewType::kPrefixSize, sizeof(r_inlined));
+    return l_inlined == r_inlined;
+  }
+
+  // Sizes are equal and this is not inline, therefore both are out
+  // of line and have kPrefixSize first in common.
+  const uint8_t* l_data = l_buffers[l.ref.buffer_index]->data() + l.ref.offset;
+  const uint8_t* r_data = r_buffers[r.ref.buffer_index]->data() + r.ref.offset;
+  return memcmp(l_data + BinaryViewType::kPrefixSize,
+                r_data + BinaryViewType::kPrefixSize,
+                l.size() - BinaryViewType::kPrefixSize) == 0;
+}
+
+}  // namespace arrow::util

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bit_block_counter.h

@@ -0,0 +1,570 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <algorithm>
+#include <cstdint>
+#include <limits>
+#include <memory>
+
+#include "arrow/buffer.h"
+#include "arrow/status.h"
+#include "arrow/util/bit_util.h"
+#include "arrow/util/endian.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/ubsan.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+namespace detail {
+
+inline uint64_t LoadWord(const uint8_t* bytes) {
+  return bit_util::ToLittleEndian(util::SafeLoadAs<uint64_t>(bytes));
+}
+
+inline uint64_t ShiftWord(uint64_t current, uint64_t next, int64_t shift) {
+  if (shift == 0) {
+    return current;
+  }
+  return (current >> shift) | (next << (64 - shift));
+}
+
+// These templates are here to help with unit tests
+
+template <typename T>
+constexpr T BitNot(T x) {
+  return ~x;
+}
+
+template <>
+constexpr bool BitNot(bool x) {
+  return !x;
+}
+
+struct BitBlockAnd {
+  template <typename T>
+  static constexpr T Call(T left, T right) {
+    return left & right;
+  }
+};
+
+struct BitBlockAndNot {
+  template <typename T>
+  static constexpr T Call(T left, T right) {
+    return left & BitNot(right);
+  }
+};
+
+struct BitBlockOr {
+  template <typename T>
+  static constexpr T Call(T left, T right) {
+    return left | right;
+  }
+};
+
+struct BitBlockOrNot {
+  template <typename T>
+  static constexpr T Call(T left, T right) {
+    return left | BitNot(right);
+  }
+};
+
+}  // namespace detail
+
+/// \brief Return value from bit block counters: the total number of bits and
+/// the number of set bits.
+struct BitBlockCount {
+  int16_t length;
+  int16_t popcount;
+
+  bool NoneSet() const { return this->popcount == 0; }
+  bool AllSet() const { return this->length == this->popcount; }
+};
+
+/// \brief A class that scans through a true/false bitmap to compute popcounts
+/// 64 or 256 bits at a time. This is used to accelerate processing of
+/// mostly-not-null array data.
+class ARROW_EXPORT BitBlockCounter {
+ public:
+  BitBlockCounter(const uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(util::MakeNonNull(bitmap) + start_offset / 8),
+        bits_remaining_(length),
+        offset_(start_offset % 8) {}
+
+  /// \brief The bit size of each word run
+  static constexpr int64_t kWordBits = 64;
+
+  /// \brief The bit size of four words run
+  static constexpr int64_t kFourWordsBits = kWordBits * 4;
+
+  /// \brief Return the next run of available bits, usually 256. The returned
+  /// pair contains the size of run and the number of true values. The last
+  /// block will have a length less than 256 if the bitmap length is not a
+  /// multiple of 256, and will return 0-length blocks in subsequent
+  /// invocations.
+  BitBlockCount NextFourWords() {
+    using detail::LoadWord;
+    using detail::ShiftWord;
+
+    if (!bits_remaining_) {
+      return {0, 0};
+    }
+    int64_t total_popcount = 0;
+    if (offset_ == 0) {
+      if (bits_remaining_ < kFourWordsBits) {
+        return GetBlockSlow(kFourWordsBits);
+      }
+      total_popcount += bit_util::PopCount(LoadWord(bitmap_));
+      total_popcount += bit_util::PopCount(LoadWord(bitmap_ + 8));
+      total_popcount += bit_util::PopCount(LoadWord(bitmap_ + 16));
+      total_popcount += bit_util::PopCount(LoadWord(bitmap_ + 24));
+    } else {
+      // When the offset is > 0, we need there to be a word beyond the last
+      // aligned word in the bitmap for the bit shifting logic.
+      if (bits_remaining_ < 5 * kFourWordsBits - offset_) {
+        return GetBlockSlow(kFourWordsBits);
+      }
+      auto current = LoadWord(bitmap_);
+      auto next = LoadWord(bitmap_ + 8);
+      total_popcount += bit_util::PopCount(ShiftWord(current, next, offset_));
+      current = next;
+      next = LoadWord(bitmap_ + 16);
+      total_popcount += bit_util::PopCount(ShiftWord(current, next, offset_));
+      current = next;
+      next = LoadWord(bitmap_ + 24);
+      total_popcount += bit_util::PopCount(ShiftWord(current, next, offset_));
+      current = next;
+      next = LoadWord(bitmap_ + 32);
+      total_popcount += bit_util::PopCount(ShiftWord(current, next, offset_));
+    }
+    bitmap_ += bit_util::BytesForBits(kFourWordsBits);
+    bits_remaining_ -= kFourWordsBits;
+    return {256, static_cast<int16_t>(total_popcount)};
+  }
+
+  /// \brief Return the next run of available bits, usually 64. The returned
+  /// pair contains the size of run and the number of true values. The last
+  /// block will have a length less than 64 if the bitmap length is not a
+  /// multiple of 64, and will return 0-length blocks in subsequent
+  /// invocations.
+  BitBlockCount NextWord() {
+    using detail::LoadWord;
+    using detail::ShiftWord;
+
+    if (!bits_remaining_) {
+      return {0, 0};
+    }
+    int64_t popcount = 0;
+    if (offset_ == 0) {
+      if (bits_remaining_ < kWordBits) {
+        return GetBlockSlow(kWordBits);
+      }
+      popcount = bit_util::PopCount(LoadWord(bitmap_));
+    } else {
+      // When the offset is > 0, we need there to be a word beyond the last
+      // aligned word in the bitmap for the bit shifting logic.
+      if (bits_remaining_ < 2 * kWordBits - offset_) {
+        return GetBlockSlow(kWordBits);
+      }
+      popcount = bit_util::PopCount(
+          ShiftWord(LoadWord(bitmap_), LoadWord(bitmap_ + 8), offset_));
+    }
+    bitmap_ += kWordBits / 8;
+    bits_remaining_ -= kWordBits;
+    return {64, static_cast<int16_t>(popcount)};
+  }
+
+ private:
+  /// \brief Return block with the requested size when doing word-wise
+  /// computation is not possible due to inadequate bits remaining.
+  BitBlockCount GetBlockSlow(int64_t block_size) noexcept;
+
+  const uint8_t* bitmap_;
+  int64_t bits_remaining_;
+  int64_t offset_;
+};
+
+/// \brief A tool to iterate through a possibly nonexistent validity bitmap,
+/// to allow us to write one code path for both the with-nulls and no-nulls
+/// cases without giving up a lot of performance.
+class ARROW_EXPORT OptionalBitBlockCounter {
+ public:
+  // validity_bitmap may be NULLPTR
+  OptionalBitBlockCounter(const uint8_t* validity_bitmap, int64_t offset, int64_t length);
+
+  // validity_bitmap may be null
+  OptionalBitBlockCounter(const std::shared_ptr<Buffer>& validity_bitmap, int64_t offset,
+                          int64_t length);
+
+  /// Return block count for next word when the bitmap is available otherwise
+  /// return a block with length up to INT16_MAX when there is no validity
+  /// bitmap (so all the referenced values are not null).
+  BitBlockCount NextBlock() {
+    static constexpr int64_t kMaxBlockSize = std::numeric_limits<int16_t>::max();
+    if (has_bitmap_) {
+      BitBlockCount block = counter_.NextWord();
+      position_ += block.length;
+      return block;
+    } else {
+      int16_t block_size =
+          static_cast<int16_t>(std::min(kMaxBlockSize, length_ - position_));
+      position_ += block_size;
+      // All values are non-null
+      return {block_size, block_size};
+    }
+  }
+
+  // Like NextBlock, but returns a word-sized block even when there is no
+  // validity bitmap
+  BitBlockCount NextWord() {
+    static constexpr int64_t kWordSize = 64;
+    if (has_bitmap_) {
+      BitBlockCount block = counter_.NextWord();
+      position_ += block.length;
+      return block;
+    } else {
+      int16_t block_size = static_cast<int16_t>(std::min(kWordSize, length_ - position_));
+      position_ += block_size;
+      // All values are non-null
+      return {block_size, block_size};
+    }
+  }
+
+ private:
+  const bool has_bitmap_;
+  int64_t position_;
+  int64_t length_;
+  BitBlockCounter counter_;
+};
+
+/// \brief A class that computes popcounts on the result of bitwise operations
+/// between two bitmaps, 64 bits at a time. A 64-bit word is loaded from each
+/// bitmap, then the popcount is computed on e.g. the bitwise-and of the two
+/// words.
+class ARROW_EXPORT BinaryBitBlockCounter {
+ public:
+  BinaryBitBlockCounter(const uint8_t* left_bitmap, int64_t left_offset,
+                        const uint8_t* right_bitmap, int64_t right_offset, int64_t length)
+      : left_bitmap_(util::MakeNonNull(left_bitmap) + left_offset / 8),
+        left_offset_(left_offset % 8),
+        right_bitmap_(util::MakeNonNull(right_bitmap) + right_offset / 8),
+        right_offset_(right_offset % 8),
+        bits_remaining_(length) {}
+
+  /// \brief Return the popcount of the bitwise-and of the next run of
+  /// available bits, up to 64. The returned pair contains the size of run and
+  /// the number of true values. The last block will have a length less than 64
+  /// if the bitmap length is not a multiple of 64, and will return 0-length
+  /// blocks in subsequent invocations.
+  BitBlockCount NextAndWord() { return NextWord<detail::BitBlockAnd>(); }
+
+  /// \brief Computes "x & ~y" block for each available run of bits.
+  BitBlockCount NextAndNotWord() { return NextWord<detail::BitBlockAndNot>(); }
+
+  /// \brief Computes "x | y" block for each available run of bits.
+  BitBlockCount NextOrWord() { return NextWord<detail::BitBlockOr>(); }
+
+  /// \brief Computes "x | ~y" block for each available run of bits.
+  BitBlockCount NextOrNotWord() { return NextWord<detail::BitBlockOrNot>(); }
+
+ private:
+  template <class Op>
+  BitBlockCount NextWord() {
+    using detail::LoadWord;
+    using detail::ShiftWord;
+
+    if (!bits_remaining_) {
+      return {0, 0};
+    }
+    // When the offset is > 0, we need there to be a word beyond the last aligned
+    // word in the bitmap for the bit shifting logic.
+    constexpr int64_t kWordBits = BitBlockCounter::kWordBits;
+    const int64_t bits_required_to_use_words =
+        std::max(left_offset_ == 0 ? 64 : 64 + (64 - left_offset_),
+                 right_offset_ == 0 ? 64 : 64 + (64 - right_offset_));
+    if (bits_remaining_ < bits_required_to_use_words) {
+      const int16_t run_length =
+          static_cast<int16_t>(std::min(bits_remaining_, kWordBits));
+      int16_t popcount = 0;
+      for (int64_t i = 0; i < run_length; ++i) {
+        if (Op::Call(bit_util::GetBit(left_bitmap_, left_offset_ + i),
+                     bit_util::GetBit(right_bitmap_, right_offset_ + i))) {
+          ++popcount;
+        }
+      }
+      // This code path should trigger _at most_ 2 times. In the "two times"
+      // case, the first time the run length will be a multiple of 8.
+      left_bitmap_ += run_length / 8;
+      right_bitmap_ += run_length / 8;
+      bits_remaining_ -= run_length;
+      return {run_length, popcount};
+    }
+
+    int64_t popcount = 0;
+    if (left_offset_ == 0 && right_offset_ == 0) {
+      popcount =
+          bit_util::PopCount(Op::Call(LoadWord(left_bitmap_), LoadWord(right_bitmap_)));
+    } else {
+      auto left_word =
+          ShiftWord(LoadWord(left_bitmap_), LoadWord(left_bitmap_ + 8), left_offset_);
+      auto right_word =
+          ShiftWord(LoadWord(right_bitmap_), LoadWord(right_bitmap_ + 8), right_offset_);
+      popcount = bit_util::PopCount(Op::Call(left_word, right_word));
+    }
+    left_bitmap_ += kWordBits / 8;
+    right_bitmap_ += kWordBits / 8;
+    bits_remaining_ -= kWordBits;
+    return {64, static_cast<int16_t>(popcount)};
+  }
+
+  const uint8_t* left_bitmap_;
+  int64_t left_offset_;
+  const uint8_t* right_bitmap_;
+  int64_t right_offset_;
+  int64_t bits_remaining_;
+};
+
+class ARROW_EXPORT OptionalBinaryBitBlockCounter {
+ public:
+  // Any bitmap may be NULLPTR
+  OptionalBinaryBitBlockCounter(const uint8_t* left_bitmap, int64_t left_offset,
+                                const uint8_t* right_bitmap, int64_t right_offset,
+                                int64_t length);
+
+  // Any bitmap may be null
+  OptionalBinaryBitBlockCounter(const std::shared_ptr<Buffer>& left_bitmap,
+                                int64_t left_offset,
+                                const std::shared_ptr<Buffer>& right_bitmap,
+                                int64_t right_offset, int64_t length);
+
+  BitBlockCount NextAndBlock() {
+    static constexpr int64_t kMaxBlockSize = std::numeric_limits<int16_t>::max();
+    switch (has_bitmap_) {
+      case HasBitmap::BOTH: {
+        BitBlockCount block = binary_counter_.NextAndWord();
+        position_ += block.length;
+        return block;
+      }
+      case HasBitmap::ONE: {
+        BitBlockCount block = unary_counter_.NextWord();
+        position_ += block.length;
+        return block;
+      }
+      case HasBitmap::NONE:
+      default: {
+        const int16_t block_size =
+            static_cast<int16_t>(std::min(kMaxBlockSize, length_ - position_));
+        position_ += block_size;
+        // All values are non-null
+        return {block_size, block_size};
+      }
+    }
+  }
+
+  BitBlockCount NextOrNotBlock() {
+    static constexpr int64_t kMaxBlockSize = std::numeric_limits<int16_t>::max();
+    switch (has_bitmap_) {
+      case HasBitmap::BOTH: {
+        BitBlockCount block = binary_counter_.NextOrNotWord();
+        position_ += block.length;
+        return block;
+      }
+      case HasBitmap::ONE: {
+        BitBlockCount block = unary_counter_.NextWord();
+        position_ += block.length;
+        return block;
+      }
+      case HasBitmap::NONE:
+      default: {
+        const int16_t block_size =
+            static_cast<int16_t>(std::min(kMaxBlockSize, length_ - position_));
+        position_ += block_size;
+        // All values are non-null
+        return {block_size, block_size};
+      }
+    }
+  }
+
+ private:
+  enum class HasBitmap : int { BOTH, ONE, NONE };
+
+  const HasBitmap has_bitmap_;
+  int64_t position_;
+  int64_t length_;
+  BitBlockCounter unary_counter_;
+  BinaryBitBlockCounter binary_counter_;
+
+  static HasBitmap HasBitmapFromBitmaps(bool has_left, bool has_right) {
+    switch (static_cast<int>(has_left) + static_cast<int>(has_right)) {
+      case 0:
+        return HasBitmap::NONE;
+      case 1:
+        return HasBitmap::ONE;
+      default:  // 2
+        return HasBitmap::BOTH;
+    }
+  }
+};
+
+// Functional-style bit block visitors.
+
+template <typename VisitNotNull, typename VisitNull>
+static Status VisitBitBlocks(const uint8_t* bitmap, int64_t offset, int64_t length,
+                             VisitNotNull&& visit_not_null, VisitNull&& visit_null) {
+  internal::OptionalBitBlockCounter bit_counter(bitmap, offset, length);
+  int64_t position = 0;
+  while (position < length) {
+    internal::BitBlockCount block = bit_counter.NextBlock();
+    if (block.AllSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        ARROW_RETURN_NOT_OK(visit_not_null(position));
+      }
+    } else if (block.NoneSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        ARROW_RETURN_NOT_OK(visit_null());
+      }
+    } else {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        if (bit_util::GetBit(bitmap, offset + position)) {
+          ARROW_RETURN_NOT_OK(visit_not_null(position));
+        } else {
+          ARROW_RETURN_NOT_OK(visit_null());
+        }
+      }
+    }
+  }
+  return Status::OK();
+}
+
+template <typename VisitNotNull, typename VisitNull>
+static void VisitBitBlocksVoid(const uint8_t* bitmap, int64_t offset, int64_t length,
+                               VisitNotNull&& visit_not_null, VisitNull&& visit_null) {
+  internal::OptionalBitBlockCounter bit_counter(bitmap, offset, length);
+  int64_t position = 0;
+  while (position < length) {
+    internal::BitBlockCount block = bit_counter.NextBlock();
+    if (block.AllSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        visit_not_null(position);
+      }
+    } else if (block.NoneSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        visit_null();
+      }
+    } else {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        if (bit_util::GetBit(bitmap, offset + position)) {
+          visit_not_null(position);
+        } else {
+          visit_null();
+        }
+      }
+    }
+  }
+}
+
+template <typename VisitNotNull, typename VisitNull>
+static Status VisitTwoBitBlocks(const uint8_t* left_bitmap, int64_t left_offset,
+                                const uint8_t* right_bitmap, int64_t right_offset,
+                                int64_t length, VisitNotNull&& visit_not_null,
+                                VisitNull&& visit_null) {
+  if (left_bitmap == NULLPTR || right_bitmap == NULLPTR) {
+    // At most one bitmap is present
+    if (left_bitmap == NULLPTR) {
+      return VisitBitBlocks(right_bitmap, right_offset, length,
+                            std::forward<VisitNotNull>(visit_not_null),
+                            std::forward<VisitNull>(visit_null));
+    } else {
+      return VisitBitBlocks(left_bitmap, left_offset, length,
+                            std::forward<VisitNotNull>(visit_not_null),
+                            std::forward<VisitNull>(visit_null));
+    }
+  }
+  BinaryBitBlockCounter bit_counter(left_bitmap, left_offset, right_bitmap, right_offset,
+                                    length);
+  int64_t position = 0;
+  while (position < length) {
+    BitBlockCount block = bit_counter.NextAndWord();
+    if (block.AllSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        ARROW_RETURN_NOT_OK(visit_not_null(position));
+      }
+    } else if (block.NoneSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        ARROW_RETURN_NOT_OK(visit_null());
+      }
+    } else {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        if (bit_util::GetBit(left_bitmap, left_offset + position) &&
+            bit_util::GetBit(right_bitmap, right_offset + position)) {
+          ARROW_RETURN_NOT_OK(visit_not_null(position));
+        } else {
+          ARROW_RETURN_NOT_OK(visit_null());
+        }
+      }
+    }
+  }
+  return Status::OK();
+}
+
+template <typename VisitNotNull, typename VisitNull>
+static void VisitTwoBitBlocksVoid(const uint8_t* left_bitmap, int64_t left_offset,
+                                  const uint8_t* right_bitmap, int64_t right_offset,
+                                  int64_t length, VisitNotNull&& visit_not_null,
+                                  VisitNull&& visit_null) {
+  if (left_bitmap == NULLPTR || right_bitmap == NULLPTR) {
+    // At most one bitmap is present
+    if (left_bitmap == NULLPTR) {
+      return VisitBitBlocksVoid(right_bitmap, right_offset, length,
+                                std::forward<VisitNotNull>(visit_not_null),
+                                std::forward<VisitNull>(visit_null));
+    } else {
+      return VisitBitBlocksVoid(left_bitmap, left_offset, length,
+                                std::forward<VisitNotNull>(visit_not_null),
+                                std::forward<VisitNull>(visit_null));
+    }
+  }
+  BinaryBitBlockCounter bit_counter(left_bitmap, left_offset, right_bitmap, right_offset,
+                                    length);
+  int64_t position = 0;
+  while (position < length) {
+    BitBlockCount block = bit_counter.NextAndWord();
+    if (block.AllSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        visit_not_null(position);
+      }
+    } else if (block.NoneSet()) {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        visit_null();
+      }
+    } else {
+      for (int64_t i = 0; i < block.length; ++i, ++position) {
+        if (bit_util::GetBit(left_bitmap, left_offset + position) &&
+            bit_util::GetBit(right_bitmap, right_offset + position)) {
+          visit_not_null(position);
+        } else {
+          visit_null();
+        }
+      }
+    }
+  }
+}
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bit_run_reader.h

@@ -0,0 +1,515 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+#include <string>
+
+#include "arrow/util/bit_util.h"
+#include "arrow/util/bitmap_reader.h"
+#include "arrow/util/endian.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+struct BitRun {
+  int64_t length;
+  // Whether bits are set at this point.
+  bool set;
+
+  std::string ToString() const {
+    return std::string("{Length: ") + std::to_string(length) +
+           ", set=" + std::to_string(set) + "}";
+  }
+};
+
+inline bool operator==(const BitRun& lhs, const BitRun& rhs) {
+  return lhs.length == rhs.length && lhs.set == rhs.set;
+}
+
+inline bool operator!=(const BitRun& lhs, const BitRun& rhs) {
+  return lhs.length != rhs.length || lhs.set != rhs.set;
+}
+
+class BitRunReaderLinear {
+ public:
+  BitRunReaderLinear(const uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : reader_(bitmap, start_offset, length) {}
+
+  BitRun NextRun() {
+    BitRun rl = {/*length=*/0, reader_.IsSet()};
+    // Advance while the values are equal and not at the end of list.
+    while (reader_.position() < reader_.length() && reader_.IsSet() == rl.set) {
+      rl.length++;
+      reader_.Next();
+    }
+    return rl;
+  }
+
+ private:
+  BitmapReader reader_;
+};
+
+#if ARROW_LITTLE_ENDIAN
+/// A convenience class for counting the number of contiguous set/unset bits
+/// in a bitmap.
+class ARROW_EXPORT BitRunReader {
+ public:
+  /// \brief Constructs new BitRunReader.
+  ///
+  /// \param[in] bitmap source data
+  /// \param[in] start_offset bit offset into the source data
+  /// \param[in] length number of bits to copy
+  BitRunReader(const uint8_t* bitmap, int64_t start_offset, int64_t length);
+
+  /// Returns a new BitRun containing the number of contiguous
+  /// bits with the same value.  length == 0 indicates the
+  /// end of the bitmap.
+  BitRun NextRun() {
+    if (ARROW_PREDICT_FALSE(position_ >= length_)) {
+      return {/*length=*/0, false};
+    }
+    // This implementation relies on a efficient implementations of
+    // CountTrailingZeros and assumes that runs are more often then
+    // not.  The logic is to incrementally find the next bit change
+    // from the current position.  This is done by zeroing all
+    // bits in word_ up to position_ and using the TrailingZeroCount
+    // to find the index of the next set bit.
+
+    // The runs alternate on each call, so flip the bit.
+    current_run_bit_set_ = !current_run_bit_set_;
+
+    int64_t start_position = position_;
+    int64_t start_bit_offset = start_position & 63;
+    // Invert the word for proper use of CountTrailingZeros and
+    // clear bits so CountTrailingZeros can do it magic.
+    word_ = ~word_ & ~bit_util::LeastSignificantBitMask(start_bit_offset);
+
+    // Go  forward until the next change from unset to set.
+    int64_t new_bits = bit_util::CountTrailingZeros(word_) - start_bit_offset;
+    position_ += new_bits;
+
+    if (ARROW_PREDICT_FALSE(bit_util::IsMultipleOf64(position_)) &&
+        ARROW_PREDICT_TRUE(position_ < length_)) {
+      // Continue extending position while we can advance an entire word.
+      // (updates position_ accordingly).
+      AdvanceUntilChange();
+    }
+
+    return {/*length=*/position_ - start_position, current_run_bit_set_};
+  }
+
+ private:
+  void AdvanceUntilChange() {
+    int64_t new_bits = 0;
+    do {
+      // Advance the position of the bitmap for loading.
+      bitmap_ += sizeof(uint64_t);
+      LoadNextWord();
+      new_bits = bit_util::CountTrailingZeros(word_);
+      // Continue calculating run length.
+      position_ += new_bits;
+    } while (ARROW_PREDICT_FALSE(bit_util::IsMultipleOf64(position_)) &&
+             ARROW_PREDICT_TRUE(position_ < length_) && new_bits > 0);
+  }
+
+  void LoadNextWord() { return LoadWord(length_ - position_); }
+
+  // Helper method for Loading the next word.
+  void LoadWord(int64_t bits_remaining) {
+    word_ = 0;
+    // we need at least an extra byte in this case.
+    if (ARROW_PREDICT_TRUE(bits_remaining >= 64)) {
+      std::memcpy(&word_, bitmap_, 8);
+    } else {
+      int64_t bytes_to_load = bit_util::BytesForBits(bits_remaining);
+      auto word_ptr = reinterpret_cast<uint8_t*>(&word_);
+      std::memcpy(word_ptr, bitmap_, bytes_to_load);
+      // Ensure stoppage at last bit in bitmap by reversing the next higher
+      // order bit.
+      bit_util::SetBitTo(word_ptr, bits_remaining,
+                         !bit_util::GetBit(word_ptr, bits_remaining - 1));
+    }
+
+    // Two cases:
+    //   1. For unset, CountTrailingZeros works naturally so we don't
+    //   invert the word.
+    //   2. Otherwise invert so we can use CountTrailingZeros.
+    if (current_run_bit_set_) {
+      word_ = ~word_;
+    }
+  }
+  const uint8_t* bitmap_;
+  int64_t position_;
+  int64_t length_;
+  uint64_t word_;
+  bool current_run_bit_set_;
+};
+#else
+using BitRunReader = BitRunReaderLinear;
+#endif
+
+struct SetBitRun {
+  int64_t position;
+  int64_t length;
+
+  bool AtEnd() const { return length == 0; }
+
+  std::string ToString() const {
+    return std::string("{pos=") + std::to_string(position) +
+           ", len=" + std::to_string(length) + "}";
+  }
+
+  bool operator==(const SetBitRun& other) const {
+    return position == other.position && length == other.length;
+  }
+  bool operator!=(const SetBitRun& other) const {
+    return position != other.position || length != other.length;
+  }
+};
+
+template <bool Reverse>
+class BaseSetBitRunReader {
+ public:
+  /// \brief Constructs new SetBitRunReader.
+  ///
+  /// \param[in] bitmap source data
+  /// \param[in] start_offset bit offset into the source data
+  /// \param[in] length number of bits to copy
+  ARROW_NOINLINE
+  BaseSetBitRunReader(const uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(util::MakeNonNull(bitmap)),
+        length_(length),
+        remaining_(length_),
+        current_word_(0),
+        current_num_bits_(0) {
+    if (Reverse) {
+      bitmap_ += (start_offset + length) / 8;
+      const int8_t end_bit_offset = static_cast<int8_t>((start_offset + length) % 8);
+      if (length > 0 && end_bit_offset) {
+        // Get LSBs from last byte
+        ++bitmap_;
+        current_num_bits_ =
+            std::min(static_cast<int32_t>(length), static_cast<int32_t>(end_bit_offset));
+        current_word_ = LoadPartialWord(8 - end_bit_offset, current_num_bits_);
+      }
+    } else {
+      bitmap_ += start_offset / 8;
+      const int8_t bit_offset = static_cast<int8_t>(start_offset % 8);
+      if (length > 0 && bit_offset) {
+        // Get MSBs from first byte
+        current_num_bits_ =
+            std::min(static_cast<int32_t>(length), static_cast<int32_t>(8 - bit_offset));
+        current_word_ = LoadPartialWord(bit_offset, current_num_bits_);
+      }
+    }
+  }
+
+  ARROW_NOINLINE
+  SetBitRun NextRun() {
+    int64_t pos = 0;
+    int64_t len = 0;
+    if (current_num_bits_) {
+      const auto run = FindCurrentRun();
+      assert(remaining_ >= 0);
+      if (run.length && current_num_bits_) {
+        // The run ends in current_word_
+        return AdjustRun(run);
+      }
+      pos = run.position;
+      len = run.length;
+    }
+    if (!len) {
+      // We didn't get any ones in current_word_, so we can skip any zeros
+      // in the following words
+      SkipNextZeros();
+      if (remaining_ == 0) {
+        return {0, 0};
+      }
+      assert(current_num_bits_);
+      pos = position();
+    } else if (!current_num_bits_) {
+      if (ARROW_PREDICT_TRUE(remaining_ >= 64)) {
+        current_word_ = LoadFullWord();
+        current_num_bits_ = 64;
+      } else if (remaining_ > 0) {
+        current_word_ = LoadPartialWord(/*bit_offset=*/0, remaining_);
+        current_num_bits_ = static_cast<int32_t>(remaining_);
+      } else {
+        // No bits remaining, perhaps we found a run?
+        return AdjustRun({pos, len});
+      }
+      // If current word starts with a zero, we got a full run
+      if (!(current_word_ & kFirstBit)) {
+        return AdjustRun({pos, len});
+      }
+    }
+    // Current word should now start with a set bit
+    len += CountNextOnes();
+    return AdjustRun({pos, len});
+  }
+
+ protected:
+  int64_t position() const {
+    if (Reverse) {
+      return remaining_;
+    } else {
+      return length_ - remaining_;
+    }
+  }
+
+  SetBitRun AdjustRun(SetBitRun run) {
+    if (Reverse) {
+      assert(run.position >= run.length);
+      run.position -= run.length;
+    }
+    return run;
+  }
+
+  uint64_t LoadFullWord() {
+    uint64_t word;
+    if (Reverse) {
+      bitmap_ -= 8;
+    }
+    memcpy(&word, bitmap_, 8);
+    if (!Reverse) {
+      bitmap_ += 8;
+    }
+    return bit_util::ToLittleEndian(word);
+  }
+
+  uint64_t LoadPartialWord(int8_t bit_offset, int64_t num_bits) {
+    assert(num_bits > 0);
+    uint64_t word = 0;
+    const int64_t num_bytes = bit_util::BytesForBits(num_bits);
+    if (Reverse) {
+      // Read in the most significant bytes of the word
+      bitmap_ -= num_bytes;
+      memcpy(reinterpret_cast<char*>(&word) + 8 - num_bytes, bitmap_, num_bytes);
+      // XXX MostSignificantBitmask
+      return (bit_util::ToLittleEndian(word) << bit_offset) &
+             ~bit_util::LeastSignificantBitMask(64 - num_bits);
+    } else {
+      memcpy(&word, bitmap_, num_bytes);
+      bitmap_ += num_bytes;
+      return (bit_util::ToLittleEndian(word) >> bit_offset) &
+             bit_util::LeastSignificantBitMask(num_bits);
+    }
+  }
+
+  void SkipNextZeros() {
+    assert(current_num_bits_ == 0);
+    while (ARROW_PREDICT_TRUE(remaining_ >= 64)) {
+      current_word_ = LoadFullWord();
+      const auto num_zeros = CountFirstZeros(current_word_);
+      if (num_zeros < 64) {
+        // Run of zeros ends here
+        current_word_ = ConsumeBits(current_word_, num_zeros);
+        current_num_bits_ = 64 - num_zeros;
+        remaining_ -= num_zeros;
+        assert(remaining_ >= 0);
+        assert(current_num_bits_ >= 0);
+        return;
+      }
+      remaining_ -= 64;
+    }
+    // Run of zeros continues in last bitmap word
+    if (remaining_ > 0) {
+      current_word_ = LoadPartialWord(/*bit_offset=*/0, remaining_);
+      current_num_bits_ = static_cast<int32_t>(remaining_);
+      const auto num_zeros =
+          std::min<int32_t>(current_num_bits_, CountFirstZeros(current_word_));
+      current_word_ = ConsumeBits(current_word_, num_zeros);
+      current_num_bits_ -= num_zeros;
+      remaining_ -= num_zeros;
+      assert(remaining_ >= 0);
+      assert(current_num_bits_ >= 0);
+    }
+  }
+
+  int64_t CountNextOnes() {
+    assert(current_word_ & kFirstBit);
+
+    int64_t len;
+    if (~current_word_) {
+      const auto num_ones = CountFirstZeros(~current_word_);
+      assert(num_ones <= current_num_bits_);
+      assert(num_ones <= remaining_);
+      remaining_ -= num_ones;
+      current_word_ = ConsumeBits(current_word_, num_ones);
+      current_num_bits_ -= num_ones;
+      if (current_num_bits_) {
+        // Run of ones ends here
+        return num_ones;
+      }
+      len = num_ones;
+    } else {
+      // current_word_ is all ones
+      remaining_ -= 64;
+      current_num_bits_ = 0;
+      len = 64;
+    }
+
+    while (ARROW_PREDICT_TRUE(remaining_ >= 64)) {
+      current_word_ = LoadFullWord();
+      const auto num_ones = CountFirstZeros(~current_word_);
+      len += num_ones;
+      remaining_ -= num_ones;
+      if (num_ones < 64) {
+        // Run of ones ends here
+        current_word_ = ConsumeBits(current_word_, num_ones);
+        current_num_bits_ = 64 - num_ones;
+        return len;
+      }
+    }
+    // Run of ones continues in last bitmap word
+    if (remaining_ > 0) {
+      current_word_ = LoadPartialWord(/*bit_offset=*/0, remaining_);
+      current_num_bits_ = static_cast<int32_t>(remaining_);
+      const auto num_ones = CountFirstZeros(~current_word_);
+      assert(num_ones <= current_num_bits_);
+      assert(num_ones <= remaining_);
+      current_word_ = ConsumeBits(current_word_, num_ones);
+      current_num_bits_ -= num_ones;
+      remaining_ -= num_ones;
+      len += num_ones;
+    }
+    return len;
+  }
+
+  SetBitRun FindCurrentRun() {
+    // Skip any pending zeros
+    const auto num_zeros = CountFirstZeros(current_word_);
+    if (num_zeros >= current_num_bits_) {
+      remaining_ -= current_num_bits_;
+      current_word_ = 0;
+      current_num_bits_ = 0;
+      return {0, 0};
+    }
+    assert(num_zeros <= remaining_);
+    current_word_ = ConsumeBits(current_word_, num_zeros);
+    current_num_bits_ -= num_zeros;
+    remaining_ -= num_zeros;
+    const int64_t pos = position();
+    // Count any ones
+    const auto num_ones = CountFirstZeros(~current_word_);
+    assert(num_ones <= current_num_bits_);
+    assert(num_ones <= remaining_);
+    current_word_ = ConsumeBits(current_word_, num_ones);
+    current_num_bits_ -= num_ones;
+    remaining_ -= num_ones;
+    return {pos, num_ones};
+  }
+
+  inline int CountFirstZeros(uint64_t word);
+  inline uint64_t ConsumeBits(uint64_t word, int32_t num_bits);
+
+  const uint8_t* bitmap_;
+  const int64_t length_;
+  int64_t remaining_;
+  uint64_t current_word_;
+  int32_t current_num_bits_;
+
+  static constexpr uint64_t kFirstBit = Reverse ? 0x8000000000000000ULL : 1;
+};
+
+template <>
+inline int BaseSetBitRunReader<false>::CountFirstZeros(uint64_t word) {
+  return bit_util::CountTrailingZeros(word);
+}
+
+template <>
+inline int BaseSetBitRunReader<true>::CountFirstZeros(uint64_t word) {
+  return bit_util::CountLeadingZeros(word);
+}
+
+template <>
+inline uint64_t BaseSetBitRunReader<false>::ConsumeBits(uint64_t word, int32_t num_bits) {
+  return word >> num_bits;
+}
+
+template <>
+inline uint64_t BaseSetBitRunReader<true>::ConsumeBits(uint64_t word, int32_t num_bits) {
+  return word << num_bits;
+}
+
+using SetBitRunReader = BaseSetBitRunReader</*Reverse=*/false>;
+using ReverseSetBitRunReader = BaseSetBitRunReader</*Reverse=*/true>;
+
+// Functional-style bit run visitors.
+
+// XXX: Try to make this function small so the compiler can inline and optimize
+// the `visit` function, which is normally a hot loop with vectorizable code.
+// - don't inline SetBitRunReader constructor, it doesn't hurt performance
+// - un-inline NextRun hurts 'many null' cases a bit, but improves normal cases
+template <typename Visit>
+inline Status VisitSetBitRuns(const uint8_t* bitmap, int64_t offset, int64_t length,
+                              Visit&& visit) {
+  if (bitmap == NULLPTR) {
+    // Assuming all set (as in a null bitmap)
+    return visit(static_cast<int64_t>(0), static_cast<int64_t>(length));
+  }
+  SetBitRunReader reader(bitmap, offset, length);
+  while (true) {
+    const auto run = reader.NextRun();
+    if (run.length == 0) {
+      break;
+    }
+    ARROW_RETURN_NOT_OK(visit(run.position, run.length));
+  }
+  return Status::OK();
+}
+
+template <typename Visit>
+inline void VisitSetBitRunsVoid(const uint8_t* bitmap, int64_t offset, int64_t length,
+                                Visit&& visit) {
+  if (bitmap == NULLPTR) {
+    // Assuming all set (as in a null bitmap)
+    visit(static_cast<int64_t>(0), static_cast<int64_t>(length));
+    return;
+  }
+  SetBitRunReader reader(bitmap, offset, length);
+  while (true) {
+    const auto run = reader.NextRun();
+    if (run.length == 0) {
+      break;
+    }
+    visit(run.position, run.length);
+  }
+}
+
+template <typename Visit>
+inline Status VisitSetBitRuns(const std::shared_ptr<Buffer>& bitmap, int64_t offset,
+                              int64_t length, Visit&& visit) {
+  return VisitSetBitRuns(bitmap ? bitmap->data() : NULLPTR, offset, length,
+                         std::forward<Visit>(visit));
+}
+
+template <typename Visit>
+inline void VisitSetBitRunsVoid(const std::shared_ptr<Buffer>& bitmap, int64_t offset,
+                                int64_t length, Visit&& visit) {
+  VisitSetBitRunsVoid(bitmap ? bitmap->data() : NULLPTR, offset, length,
+                      std::forward<Visit>(visit));
+}
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bit_stream_utils.h

@@ -0,0 +1,529 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// From Apache Impala (incubating) as of 2016-01-29
+
+#pragma once
+
+#include <algorithm>
+#include <cstdint>
+#include <cstring>
+
+#include "arrow/util/bit_util.h"
+#include "arrow/util/bpacking.h"
+#include "arrow/util/logging.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/ubsan.h"
+
+namespace arrow {
+namespace bit_util {
+
+/// Utility class to write bit/byte streams.  This class can write data to either be
+/// bit packed or byte aligned (and a single stream that has a mix of both).
+/// This class does not allocate memory.
+class BitWriter {
+ public:
+  /// buffer: buffer to write bits to.  Buffer should be preallocated with
+  /// 'buffer_len' bytes.
+  BitWriter(uint8_t* buffer, int buffer_len) : buffer_(buffer), max_bytes_(buffer_len) {
+    Clear();
+  }
+
+  void Clear() {
+    buffered_values_ = 0;
+    byte_offset_ = 0;
+    bit_offset_ = 0;
+  }
+
+  /// The number of current bytes written, including the current byte (i.e. may include a
+  /// fraction of a byte). Includes buffered values.
+  int bytes_written() const {
+    return byte_offset_ + static_cast<int>(bit_util::BytesForBits(bit_offset_));
+  }
+  uint8_t* buffer() const { return buffer_; }
+  int buffer_len() const { return max_bytes_; }
+
+  /// Writes a value to buffered_values_, flushing to buffer_ if necessary.  This is bit
+  /// packed.  Returns false if there was not enough space. num_bits must be <= 32.
+  bool PutValue(uint64_t v, int num_bits);
+
+  /// Writes v to the next aligned byte using num_bytes. If T is larger than
+  /// num_bytes, the extra high-order bytes will be ignored. Returns false if
+  /// there was not enough space.
+  /// Assume the v is stored in buffer_ as a little-endian format
+  template <typename T>
+  bool PutAligned(T v, int num_bytes);
+
+  /// Write a Vlq encoded int to the buffer.  Returns false if there was not enough
+  /// room.  The value is written byte aligned.
+  /// For more details on vlq:
+  /// en.wikipedia.org/wiki/Variable-length_quantity
+  bool PutVlqInt(uint32_t v);
+
+  // Writes an int zigzag encoded.
+  bool PutZigZagVlqInt(int32_t v);
+
+  /// Write a Vlq encoded int64 to the buffer.  Returns false if there was not enough
+  /// room.  The value is written byte aligned.
+  /// For more details on vlq:
+  /// en.wikipedia.org/wiki/Variable-length_quantity
+  bool PutVlqInt(uint64_t v);
+
+  // Writes an int64 zigzag encoded.
+  bool PutZigZagVlqInt(int64_t v);
+
+  /// Get a pointer to the next aligned byte and advance the underlying buffer
+  /// by num_bytes.
+  /// Returns NULL if there was not enough space.
+  uint8_t* GetNextBytePtr(int num_bytes = 1);
+
+  /// Flushes all buffered values to the buffer. Call this when done writing to
+  /// the buffer.  If 'align' is true, buffered_values_ is reset and any future
+  /// writes will be written to the next byte boundary.
+  void Flush(bool align = false);
+
+ private:
+  uint8_t* buffer_;
+  int max_bytes_;
+
+  /// Bit-packed values are initially written to this variable before being memcpy'd to
+  /// buffer_. This is faster than writing values byte by byte directly to buffer_.
+  uint64_t buffered_values_;
+
+  int byte_offset_;  // Offset in buffer_
+  int bit_offset_;   // Offset in buffered_values_
+};
+
+namespace detail {
+
+inline uint64_t ReadLittleEndianWord(const uint8_t* buffer, int bytes_remaining) {
+  uint64_t le_value = 0;
+  if (ARROW_PREDICT_TRUE(bytes_remaining >= 8)) {
+    memcpy(&le_value, buffer, 8);
+  } else {
+    memcpy(&le_value, buffer, bytes_remaining);
+  }
+  return arrow::bit_util::FromLittleEndian(le_value);
+}
+
+}  // namespace detail
+
+/// Utility class to read bit/byte stream.  This class can read bits or bytes
+/// that are either byte aligned or not.  It also has utilities to read multiple
+/// bytes in one read (e.g. encoded int).
+class BitReader {
+ public:
+  BitReader() = default;
+
+  /// 'buffer' is the buffer to read from.  The buffer's length is 'buffer_len'.
+  BitReader(const uint8_t* buffer, int buffer_len) : BitReader() {
+    Reset(buffer, buffer_len);
+  }
+
+  void Reset(const uint8_t* buffer, int buffer_len) {
+    buffer_ = buffer;
+    max_bytes_ = buffer_len;
+    byte_offset_ = 0;
+    bit_offset_ = 0;
+    buffered_values_ =
+        detail::ReadLittleEndianWord(buffer_ + byte_offset_, max_bytes_ - byte_offset_);
+  }
+
+  /// Gets the next value from the buffer.  Returns true if 'v' could be read or false if
+  /// there are not enough bytes left.
+  template <typename T>
+  bool GetValue(int num_bits, T* v);
+
+  /// Get a number of values from the buffer. Return the number of values actually read.
+  template <typename T>
+  int GetBatch(int num_bits, T* v, int batch_size);
+
+  /// Reads a 'num_bytes'-sized value from the buffer and stores it in 'v'. T
+  /// needs to be a little-endian native type and big enough to store
+  /// 'num_bytes'. The value is assumed to be byte-aligned so the stream will
+  /// be advanced to the start of the next byte before 'v' is read. Returns
+  /// false if there are not enough bytes left.
+  /// Assume the v was stored in buffer_ as a little-endian format
+  template <typename T>
+  bool GetAligned(int num_bytes, T* v);
+
+  /// Advances the stream by a number of bits. Returns true if succeed or false if there
+  /// are not enough bits left.
+  bool Advance(int64_t num_bits);
+
+  /// Reads a vlq encoded int from the stream.  The encoded int must start at
+  /// the beginning of a byte. Return false if there were not enough bytes in
+  /// the buffer.
+  bool GetVlqInt(uint32_t* v);
+
+  // Reads a zigzag encoded int `into` v.
+  bool GetZigZagVlqInt(int32_t* v);
+
+  /// Reads a vlq encoded int64 from the stream.  The encoded int must start at
+  /// the beginning of a byte. Return false if there were not enough bytes in
+  /// the buffer.
+  bool GetVlqInt(uint64_t* v);
+
+  // Reads a zigzag encoded int64 `into` v.
+  bool GetZigZagVlqInt(int64_t* v);
+
+  /// Returns the number of bytes left in the stream, not including the current
+  /// byte (i.e., there may be an additional fraction of a byte).
+  int bytes_left() const {
+    return max_bytes_ -
+           (byte_offset_ + static_cast<int>(bit_util::BytesForBits(bit_offset_)));
+  }
+
+  /// Maximum byte length of a vlq encoded int
+  static constexpr int kMaxVlqByteLength = 5;
+
+  /// Maximum byte length of a vlq encoded int64
+  static constexpr int kMaxVlqByteLengthForInt64 = 10;
+
+ private:
+  const uint8_t* buffer_;
+  int max_bytes_;
+
+  /// Bytes are memcpy'd from buffer_ and values are read from this variable. This is
+  /// faster than reading values byte by byte directly from buffer_.
+  uint64_t buffered_values_;
+
+  int byte_offset_;  // Offset in buffer_
+  int bit_offset_;   // Offset in buffered_values_
+};
+
+inline bool BitWriter::PutValue(uint64_t v, int num_bits) {
+  DCHECK_LE(num_bits, 64);
+  if (num_bits < 64) {
+    DCHECK_EQ(v >> num_bits, 0) << "v = " << v << ", num_bits = " << num_bits;
+  }
+
+  if (ARROW_PREDICT_FALSE(byte_offset_ * 8 + bit_offset_ + num_bits > max_bytes_ * 8))
+    return false;
+
+  buffered_values_ |= v << bit_offset_;
+  bit_offset_ += num_bits;
+
+  if (ARROW_PREDICT_FALSE(bit_offset_ >= 64)) {
+    // Flush buffered_values_ and write out bits of v that did not fit
+    buffered_values_ = arrow::bit_util::ToLittleEndian(buffered_values_);
+    memcpy(buffer_ + byte_offset_, &buffered_values_, 8);
+    buffered_values_ = 0;
+    byte_offset_ += 8;
+    bit_offset_ -= 64;
+    buffered_values_ =
+        (num_bits - bit_offset_ == 64) ? 0 : (v >> (num_bits - bit_offset_));
+  }
+  DCHECK_LT(bit_offset_, 64);
+  return true;
+}
+
+inline void BitWriter::Flush(bool align) {
+  int num_bytes = static_cast<int>(bit_util::BytesForBits(bit_offset_));
+  DCHECK_LE(byte_offset_ + num_bytes, max_bytes_);
+  auto buffered_values = arrow::bit_util::ToLittleEndian(buffered_values_);
+  memcpy(buffer_ + byte_offset_, &buffered_values, num_bytes);
+
+  if (align) {
+    buffered_values_ = 0;
+    byte_offset_ += num_bytes;
+    bit_offset_ = 0;
+  }
+}
+
+inline uint8_t* BitWriter::GetNextBytePtr(int num_bytes) {
+  Flush(/* align */ true);
+  DCHECK_LE(byte_offset_, max_bytes_);
+  if (byte_offset_ + num_bytes > max_bytes_) return NULL;
+  uint8_t* ptr = buffer_ + byte_offset_;
+  byte_offset_ += num_bytes;
+  return ptr;
+}
+
+template <typename T>
+inline bool BitWriter::PutAligned(T val, int num_bytes) {
+  uint8_t* ptr = GetNextBytePtr(num_bytes);
+  if (ptr == NULL) return false;
+  val = arrow::bit_util::ToLittleEndian(val);
+  memcpy(ptr, &val, num_bytes);
+  return true;
+}
+
+namespace detail {
+
+template <typename T>
+inline void GetValue_(int num_bits, T* v, int max_bytes, const uint8_t* buffer,
+                      int* bit_offset, int* byte_offset, uint64_t* buffered_values) {
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4800)
+#endif
+  *v = static_cast<T>(bit_util::TrailingBits(*buffered_values, *bit_offset + num_bits) >>
+                      *bit_offset);
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+  *bit_offset += num_bits;
+  if (*bit_offset >= 64) {
+    *byte_offset += 8;
+    *bit_offset -= 64;
+
+    *buffered_values =
+        detail::ReadLittleEndianWord(buffer + *byte_offset, max_bytes - *byte_offset);
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4800 4805)
+#endif
+    // Read bits of v that crossed into new buffered_values_
+    if (ARROW_PREDICT_TRUE(num_bits - *bit_offset < static_cast<int>(8 * sizeof(T)))) {
+      // if shift exponent(num_bits - *bit_offset) is not less than sizeof(T), *v will not
+      // change and the following code may cause a runtime error that the shift exponent
+      // is too large
+      *v = *v | static_cast<T>(bit_util::TrailingBits(*buffered_values, *bit_offset)
+                               << (num_bits - *bit_offset));
+    }
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+    DCHECK_LE(*bit_offset, 64);
+  }
+}
+
+}  // namespace detail
+
+template <typename T>
+inline bool BitReader::GetValue(int num_bits, T* v) {
+  return GetBatch(num_bits, v, 1) == 1;
+}
+
+template <typename T>
+inline int BitReader::GetBatch(int num_bits, T* v, int batch_size) {
+  DCHECK(buffer_ != NULL);
+  DCHECK_LE(num_bits, static_cast<int>(sizeof(T) * 8)) << "num_bits: " << num_bits;
+
+  int bit_offset = bit_offset_;
+  int byte_offset = byte_offset_;
+  uint64_t buffered_values = buffered_values_;
+  int max_bytes = max_bytes_;
+  const uint8_t* buffer = buffer_;
+
+  const int64_t needed_bits = num_bits * static_cast<int64_t>(batch_size);
+  constexpr uint64_t kBitsPerByte = 8;
+  const int64_t remaining_bits =
+      static_cast<int64_t>(max_bytes - byte_offset) * kBitsPerByte - bit_offset;
+  if (remaining_bits < needed_bits) {
+    batch_size = static_cast<int>(remaining_bits / num_bits);
+  }
+
+  int i = 0;
+  if (ARROW_PREDICT_FALSE(bit_offset != 0)) {
+    for (; i < batch_size && bit_offset != 0; ++i) {
+      detail::GetValue_(num_bits, &v[i], max_bytes, buffer, &bit_offset, &byte_offset,
+                        &buffered_values);
+    }
+  }
+
+  if (sizeof(T) == 4) {
+    int num_unpacked =
+        internal::unpack32(reinterpret_cast<const uint32_t*>(buffer + byte_offset),
+                           reinterpret_cast<uint32_t*>(v + i), batch_size - i, num_bits);
+    i += num_unpacked;
+    byte_offset += num_unpacked * num_bits / 8;
+  } else if (sizeof(T) == 8 && num_bits > 32) {
+    // Use unpack64 only if num_bits is larger than 32
+    // TODO (ARROW-13677): improve the performance of internal::unpack64
+    // and remove the restriction of num_bits
+    int num_unpacked =
+        internal::unpack64(buffer + byte_offset, reinterpret_cast<uint64_t*>(v + i),
+                           batch_size - i, num_bits);
+    i += num_unpacked;
+    byte_offset += num_unpacked * num_bits / 8;
+  } else {
+    // TODO: revisit this limit if necessary
+    DCHECK_LE(num_bits, 32);
+    const int buffer_size = 1024;
+    uint32_t unpack_buffer[buffer_size];
+    while (i < batch_size) {
+      int unpack_size = std::min(buffer_size, batch_size - i);
+      int num_unpacked =
+          internal::unpack32(reinterpret_cast<const uint32_t*>(buffer + byte_offset),
+                             unpack_buffer, unpack_size, num_bits);
+      if (num_unpacked == 0) {
+        break;
+      }
+      for (int k = 0; k < num_unpacked; ++k) {
+#ifdef _MSC_VER
+#pragma warning(push)
+#pragma warning(disable : 4800)
+#endif
+        v[i + k] = static_cast<T>(unpack_buffer[k]);
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+      }
+      i += num_unpacked;
+      byte_offset += num_unpacked * num_bits / 8;
+    }
+  }
+
+  buffered_values =
+      detail::ReadLittleEndianWord(buffer + byte_offset, max_bytes - byte_offset);
+
+  for (; i < batch_size; ++i) {
+    detail::GetValue_(num_bits, &v[i], max_bytes, buffer, &bit_offset, &byte_offset,
+                      &buffered_values);
+  }
+
+  bit_offset_ = bit_offset;
+  byte_offset_ = byte_offset;
+  buffered_values_ = buffered_values;
+
+  return batch_size;
+}
+
+template <typename T>
+inline bool BitReader::GetAligned(int num_bytes, T* v) {
+  if (ARROW_PREDICT_FALSE(num_bytes > static_cast<int>(sizeof(T)))) {
+    return false;
+  }
+
+  int bytes_read = static_cast<int>(bit_util::BytesForBits(bit_offset_));
+  if (ARROW_PREDICT_FALSE(byte_offset_ + bytes_read + num_bytes > max_bytes_)) {
+    return false;
+  }
+
+  // Advance byte_offset to next unread byte and read num_bytes
+  byte_offset_ += bytes_read;
+  if constexpr (std::is_same_v<T, bool>) {
+    // ARROW-18031: if we're trying to get an aligned bool, just check
+    // the LSB of the next byte and move on. If we memcpy + FromLittleEndian
+    // as usual, we have potential undefined behavior for bools if the value
+    // isn't 0 or 1
+    *v = *(buffer_ + byte_offset_) & 1;
+  } else {
+    memcpy(v, buffer_ + byte_offset_, num_bytes);
+    *v = arrow::bit_util::FromLittleEndian(*v);
+  }
+  byte_offset_ += num_bytes;
+
+  bit_offset_ = 0;
+  buffered_values_ =
+      detail::ReadLittleEndianWord(buffer_ + byte_offset_, max_bytes_ - byte_offset_);
+  return true;
+}
+
+inline bool BitReader::Advance(int64_t num_bits) {
+  int64_t bits_required = bit_offset_ + num_bits;
+  int64_t bytes_required = bit_util::BytesForBits(bits_required);
+  if (ARROW_PREDICT_FALSE(bytes_required > max_bytes_ - byte_offset_)) {
+    return false;
+  }
+  byte_offset_ += static_cast<int>(bits_required >> 3);
+  bit_offset_ = static_cast<int>(bits_required & 7);
+  buffered_values_ =
+      detail::ReadLittleEndianWord(buffer_ + byte_offset_, max_bytes_ - byte_offset_);
+  return true;
+}
+
+inline bool BitWriter::PutVlqInt(uint32_t v) {
+  bool result = true;
+  while ((v & 0xFFFFFF80UL) != 0UL) {
+    result &= PutAligned<uint8_t>(static_cast<uint8_t>((v & 0x7F) | 0x80), 1);
+    v >>= 7;
+  }
+  result &= PutAligned<uint8_t>(static_cast<uint8_t>(v & 0x7F), 1);
+  return result;
+}
+
+inline bool BitReader::GetVlqInt(uint32_t* v) {
+  uint32_t tmp = 0;
+
+  for (int i = 0; i < kMaxVlqByteLength; i++) {
+    uint8_t byte = 0;
+    if (ARROW_PREDICT_FALSE(!GetAligned<uint8_t>(1, &byte))) {
+      return false;
+    }
+    tmp |= static_cast<uint32_t>(byte & 0x7F) << (7 * i);
+
+    if ((byte & 0x80) == 0) {
+      *v = tmp;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+inline bool BitWriter::PutZigZagVlqInt(int32_t v) {
+  uint32_t u_v = ::arrow::util::SafeCopy<uint32_t>(v);
+  u_v = (u_v << 1) ^ static_cast<uint32_t>(v >> 31);
+  return PutVlqInt(u_v);
+}
+
+inline bool BitReader::GetZigZagVlqInt(int32_t* v) {
+  uint32_t u;
+  if (!GetVlqInt(&u)) return false;
+  u = (u >> 1) ^ (~(u & 1) + 1);
+  *v = ::arrow::util::SafeCopy<int32_t>(u);
+  return true;
+}
+
+inline bool BitWriter::PutVlqInt(uint64_t v) {
+  bool result = true;
+  while ((v & 0xFFFFFFFFFFFFFF80ULL) != 0ULL) {
+    result &= PutAligned<uint8_t>(static_cast<uint8_t>((v & 0x7F) | 0x80), 1);
+    v >>= 7;
+  }
+  result &= PutAligned<uint8_t>(static_cast<uint8_t>(v & 0x7F), 1);
+  return result;
+}
+
+inline bool BitReader::GetVlqInt(uint64_t* v) {
+  uint64_t tmp = 0;
+
+  for (int i = 0; i < kMaxVlqByteLengthForInt64; i++) {
+    uint8_t byte = 0;
+    if (ARROW_PREDICT_FALSE(!GetAligned<uint8_t>(1, &byte))) {
+      return false;
+    }
+    tmp |= static_cast<uint64_t>(byte & 0x7F) << (7 * i);
+
+    if ((byte & 0x80) == 0) {
+      *v = tmp;
+      return true;
+    }
+  }
+
+  return false;
+}
+
+inline bool BitWriter::PutZigZagVlqInt(int64_t v) {
+  uint64_t u_v = ::arrow::util::SafeCopy<uint64_t>(v);
+  u_v = (u_v << 1) ^ static_cast<uint64_t>(v >> 63);
+  return PutVlqInt(u_v);
+}
+
+inline bool BitReader::GetZigZagVlqInt(int64_t* v) {
+  uint64_t u;
+  if (!GetVlqInt(&u)) return false;
+  u = (u >> 1) ^ (~(u & 1) + 1);
+  *v = ::arrow::util::SafeCopy<int64_t>(u);
+  return true;
+}
+
+}  // namespace bit_util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bit_util.h

@@ -0,0 +1,370 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#if defined(_MSC_VER)
+#if defined(_M_AMD64) || defined(_M_X64)
+#include <intrin.h>  // IWYU pragma: keep
+#include <nmmintrin.h>
+#endif
+
+#pragma intrinsic(_BitScanReverse)
+#pragma intrinsic(_BitScanForward)
+#define ARROW_POPCOUNT64 __popcnt64
+#define ARROW_POPCOUNT32 __popcnt
+#else
+#define ARROW_POPCOUNT64 __builtin_popcountll
+#define ARROW_POPCOUNT32 __builtin_popcount
+#endif
+
+#include <cstdint>
+#include <type_traits>
+
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace detail {
+
+template <typename Integer>
+typename std::make_unsigned<Integer>::type as_unsigned(Integer x) {
+  return static_cast<typename std::make_unsigned<Integer>::type>(x);
+}
+
+}  // namespace detail
+
+namespace bit_util {
+
+// The number of set bits in a given unsigned byte value, pre-computed
+//
+// Generated with the following Python code
+// output = 'static constexpr uint8_t kBytePopcount[] = {{{0}}};'
+// popcounts = [str(bin(i).count('1')) for i in range(0, 256)]
+// print(output.format(', '.join(popcounts)))
+static constexpr uint8_t kBytePopcount[] = {
+    0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3,
+    4, 4, 5, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4,
+    4, 5, 4, 5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4,
+    5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5,
+    4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2,
+    3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5,
+    5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4,
+    5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6,
+    4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8};
+
+static inline uint64_t PopCount(uint64_t bitmap) { return ARROW_POPCOUNT64(bitmap); }
+static inline uint32_t PopCount(uint32_t bitmap) { return ARROW_POPCOUNT32(bitmap); }
+
+//
+// Bit-related computations on integer values
+//
+
+// Returns the ceil of value/divisor
+constexpr int64_t CeilDiv(int64_t value, int64_t divisor) {
+  return (value == 0) ? 0 : 1 + (value - 1) / divisor;
+}
+
+// Return the number of bytes needed to fit the given number of bits
+constexpr int64_t BytesForBits(int64_t bits) {
+  // This formula avoids integer overflow on very large `bits`
+  return (bits >> 3) + ((bits & 7) != 0);
+}
+
+constexpr bool IsPowerOf2(int64_t value) {
+  return value > 0 && (value & (value - 1)) == 0;
+}
+
+constexpr bool IsPowerOf2(uint64_t value) {
+  return value > 0 && (value & (value - 1)) == 0;
+}
+
+// Returns the smallest power of two that contains v.  If v is already a
+// power of two, it is returned as is.
+static inline int64_t NextPower2(int64_t n) {
+  // Taken from
+  // http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
+  n--;
+  n |= n >> 1;
+  n |= n >> 2;
+  n |= n >> 4;
+  n |= n >> 8;
+  n |= n >> 16;
+  n |= n >> 32;
+  n++;
+  return n;
+}
+
+constexpr bool IsMultipleOf64(int64_t n) { return (n & 63) == 0; }
+
+constexpr bool IsMultipleOf8(int64_t n) { return (n & 7) == 0; }
+
+// Returns a mask for the bit_index lower order bits.
+// Only valid for bit_index in the range [0, 64).
+constexpr uint64_t LeastSignificantBitMask(int64_t bit_index) {
+  return (static_cast<uint64_t>(1) << bit_index) - 1;
+}
+
+// Returns 'value' rounded up to the nearest multiple of 'factor'
+constexpr int64_t RoundUp(int64_t value, int64_t factor) {
+  return CeilDiv(value, factor) * factor;
+}
+
+// Returns 'value' rounded down to the nearest multiple of 'factor'
+constexpr int64_t RoundDown(int64_t value, int64_t factor) {
+  return (value / factor) * factor;
+}
+
+// Returns 'value' rounded up to the nearest multiple of 'factor' when factor
+// is a power of two.
+// The result is undefined on overflow, i.e. if `value > 2**64 - factor`,
+// since we cannot return the correct result which would be 2**64.
+constexpr int64_t RoundUpToPowerOf2(int64_t value, int64_t factor) {
+  // DCHECK(value >= 0);
+  // DCHECK(IsPowerOf2(factor));
+  return (value + (factor - 1)) & ~(factor - 1);
+}
+
+constexpr uint64_t RoundUpToPowerOf2(uint64_t value, uint64_t factor) {
+  // DCHECK(IsPowerOf2(factor));
+  return (value + (factor - 1)) & ~(factor - 1);
+}
+
+constexpr int64_t RoundUpToMultipleOf8(int64_t num) { return RoundUpToPowerOf2(num, 8); }
+
+constexpr int64_t RoundUpToMultipleOf64(int64_t num) {
+  return RoundUpToPowerOf2(num, 64);
+}
+
+// Returns the number of bytes covering a sliced bitmap. Find the length
+// rounded to cover full bytes on both extremities.
+//
+// The following example represents a slice (offset=10, length=9)
+//
+// 0       8       16     24
+// |-------|-------|------|
+//           [       ]          (slice)
+//         [             ]      (same slice aligned to bytes bounds, length=16)
+//
+// The covering bytes is the length (in bytes) of this new aligned slice.
+constexpr int64_t CoveringBytes(int64_t offset, int64_t length) {
+  return (bit_util::RoundUp(length + offset, 8) - bit_util::RoundDown(offset, 8)) / 8;
+}
+
+// Returns the 'num_bits' least-significant bits of 'v'.
+static inline uint64_t TrailingBits(uint64_t v, int num_bits) {
+  if (ARROW_PREDICT_FALSE(num_bits == 0)) return 0;
+  if (ARROW_PREDICT_FALSE(num_bits >= 64)) return v;
+  int n = 64 - num_bits;
+  return (v << n) >> n;
+}
+
+/// \brief Count the number of leading zeros in an unsigned integer.
+static inline int CountLeadingZeros(uint32_t value) {
+#if defined(__clang__) || defined(__GNUC__)
+  if (value == 0) return 32;
+  return static_cast<int>(__builtin_clz(value));
+#elif defined(_MSC_VER)
+  unsigned long index;                                               // NOLINT
+  if (_BitScanReverse(&index, static_cast<unsigned long>(value))) {  // NOLINT
+    return 31 - static_cast<int>(index);
+  } else {
+    return 32;
+  }
+#else
+  int bitpos = 0;
+  while (value != 0) {
+    value >>= 1;
+    ++bitpos;
+  }
+  return 32 - bitpos;
+#endif
+}
+
+static inline int CountLeadingZeros(uint64_t value) {
+#if defined(__clang__) || defined(__GNUC__)
+  if (value == 0) return 64;
+  return static_cast<int>(__builtin_clzll(value));
+#elif defined(_MSC_VER)
+  unsigned long index;                     // NOLINT
+  if (_BitScanReverse64(&index, value)) {  // NOLINT
+    return 63 - static_cast<int>(index);
+  } else {
+    return 64;
+  }
+#else
+  int bitpos = 0;
+  while (value != 0) {
+    value >>= 1;
+    ++bitpos;
+  }
+  return 64 - bitpos;
+#endif
+}
+
+static inline int CountTrailingZeros(uint32_t value) {
+#if defined(__clang__) || defined(__GNUC__)
+  if (value == 0) return 32;
+  return static_cast<int>(__builtin_ctzl(value));
+#elif defined(_MSC_VER)
+  unsigned long index;  // NOLINT
+  if (_BitScanForward(&index, value)) {
+    return static_cast<int>(index);
+  } else {
+    return 32;
+  }
+#else
+  int bitpos = 0;
+  if (value) {
+    while (value & 1 == 0) {
+      value >>= 1;
+      ++bitpos;
+    }
+  } else {
+    bitpos = 32;
+  }
+  return bitpos;
+#endif
+}
+
+static inline int CountTrailingZeros(uint64_t value) {
+#if defined(__clang__) || defined(__GNUC__)
+  if (value == 0) return 64;
+  return static_cast<int>(__builtin_ctzll(value));
+#elif defined(_MSC_VER)
+  unsigned long index;  // NOLINT
+  if (_BitScanForward64(&index, value)) {
+    return static_cast<int>(index);
+  } else {
+    return 64;
+  }
+#else
+  int bitpos = 0;
+  if (value) {
+    while (value & 1 == 0) {
+      value >>= 1;
+      ++bitpos;
+    }
+  } else {
+    bitpos = 64;
+  }
+  return bitpos;
+#endif
+}
+
+// Returns the minimum number of bits needed to represent an unsigned value
+static inline int NumRequiredBits(uint64_t x) { return 64 - CountLeadingZeros(x); }
+
+// Returns ceil(log2(x)).
+static inline int Log2(uint64_t x) {
+  // DCHECK_GT(x, 0);
+  return NumRequiredBits(x - 1);
+}
+
+//
+// Utilities for reading and writing individual bits by their index
+// in a memory area.
+//
+
+// Bitmask selecting the k-th bit in a byte
+static constexpr uint8_t kBitmask[] = {1, 2, 4, 8, 16, 32, 64, 128};
+
+// the bitwise complement version of kBitmask
+static constexpr uint8_t kFlippedBitmask[] = {254, 253, 251, 247, 239, 223, 191, 127};
+
+// Bitmask selecting the (k - 1) preceding bits in a byte
+static constexpr uint8_t kPrecedingBitmask[] = {0, 1, 3, 7, 15, 31, 63, 127};
+static constexpr uint8_t kPrecedingWrappingBitmask[] = {255, 1, 3, 7, 15, 31, 63, 127};
+
+// the bitwise complement version of kPrecedingBitmask
+static constexpr uint8_t kTrailingBitmask[] = {255, 254, 252, 248, 240, 224, 192, 128};
+
+static constexpr bool GetBit(const uint8_t* bits, uint64_t i) {
+  return (bits[i >> 3] >> (i & 0x07)) & 1;
+}
+
+// Gets the i-th bit from a byte. Should only be used with i <= 7.
+static constexpr bool GetBitFromByte(uint8_t byte, uint8_t i) {
+  return byte & kBitmask[i];
+}
+
+static inline void ClearBit(uint8_t* bits, int64_t i) {
+  bits[i / 8] &= kFlippedBitmask[i % 8];
+}
+
+static inline void SetBit(uint8_t* bits, int64_t i) { bits[i / 8] |= kBitmask[i % 8]; }
+
+static inline void SetBitTo(uint8_t* bits, int64_t i, bool bit_is_set) {
+  // https://graphics.stanford.edu/~seander/bithacks.html
+  // "Conditionally set or clear bits without branching"
+  // NOTE: this seems to confuse Valgrind as it reads from potentially
+  // uninitialized memory
+  bits[i / 8] ^= static_cast<uint8_t>(-static_cast<uint8_t>(bit_is_set) ^ bits[i / 8]) &
+                 kBitmask[i % 8];
+}
+
+/// \brief set or clear a range of bits quickly
+ARROW_EXPORT
+void SetBitsTo(uint8_t* bits, int64_t start_offset, int64_t length, bool bits_are_set);
+
+/// \brief Sets all bits in the bitmap to true
+ARROW_EXPORT
+void SetBitmap(uint8_t* data, int64_t offset, int64_t length);
+
+/// \brief Clears all bits in the bitmap (set to false)
+ARROW_EXPORT
+void ClearBitmap(uint8_t* data, int64_t offset, int64_t length);
+
+/// Returns a mask with lower i bits set to 1. If i >= sizeof(Word)*8, all-ones will be
+/// returned
+/// ex:
+/// ref: https://stackoverflow.com/a/59523400
+template <typename Word>
+constexpr Word PrecedingWordBitmask(unsigned int const i) {
+  return static_cast<Word>(static_cast<Word>(i < sizeof(Word) * 8)
+                           << (i & (sizeof(Word) * 8 - 1))) -
+         1;
+}
+static_assert(PrecedingWordBitmask<uint8_t>(0) == 0x00, "");
+static_assert(PrecedingWordBitmask<uint8_t>(4) == 0x0f, "");
+static_assert(PrecedingWordBitmask<uint8_t>(8) == 0xff, "");
+static_assert(PrecedingWordBitmask<uint16_t>(8) == 0x00ff, "");
+
+/// \brief Create a word with low `n` bits from `low` and high `sizeof(Word)-n` bits
+/// from `high`.
+/// Word ret
+/// for (i = 0; i < sizeof(Word)*8; i++){
+///     ret[i]= i < n ? low[i]: high[i];
+/// }
+template <typename Word>
+constexpr Word SpliceWord(int n, Word low, Word high) {
+  return (high & ~PrecedingWordBitmask<Word>(n)) | (low & PrecedingWordBitmask<Word>(n));
+}
+
+/// \brief Pack integers into a bitmap in batches of 8
+template <int batch_size>
+void PackBits(const uint32_t* values, uint8_t* out) {
+  for (int i = 0; i < batch_size / 8; ++i) {
+    *out++ = static_cast<uint8_t>(values[0] | values[1] << 1 | values[2] << 2 |
+                                  values[3] << 3 | values[4] << 4 | values[5] << 5 |
+                                  values[6] << 6 | values[7] << 7);
+    values += 8;
+  }
+}
+
+}  // namespace bit_util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bitmap_builders.h

@@ -0,0 +1,43 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+#include "arrow/result.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+/// \brief Generate Bitmap with all position to `value` except for one found
+/// at `straggler_pos`.
+ARROW_EXPORT
+Result<std::shared_ptr<Buffer>> BitmapAllButOne(MemoryPool* pool, int64_t length,
+                                                int64_t straggler_pos, bool value = true);
+
+/// \brief Convert vector of bytes to bitmap buffer
+ARROW_EXPORT
+Result<std::shared_ptr<Buffer>> BytesToBits(const std::vector<uint8_t>&,
+                                            MemoryPool* pool = default_memory_pool());
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bitmap_generate.h

@@ -0,0 +1,112 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+#include <memory>
+
+#include "arrow/buffer.h"
+#include "arrow/memory_pool.h"
+#include "arrow/result.h"
+#include "arrow/util/bit_util.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+// A std::generate() like function to write sequential bits into a bitmap area.
+// Bits preceding the bitmap area are preserved, bits following the bitmap
+// area may be clobbered.
+
+template <class Generator>
+void GenerateBits(uint8_t* bitmap, int64_t start_offset, int64_t length, Generator&& g) {
+  if (length == 0) {
+    return;
+  }
+  uint8_t* cur = bitmap + start_offset / 8;
+  uint8_t bit_mask = bit_util::kBitmask[start_offset % 8];
+  uint8_t current_byte = *cur & bit_util::kPrecedingBitmask[start_offset % 8];
+
+  for (int64_t index = 0; index < length; ++index) {
+    const bool bit = g();
+    current_byte = bit ? (current_byte | bit_mask) : current_byte;
+    bit_mask = static_cast<uint8_t>(bit_mask << 1);
+    if (bit_mask == 0) {
+      bit_mask = 1;
+      *cur++ = current_byte;
+      current_byte = 0;
+    }
+  }
+  if (bit_mask != 1) {
+    *cur++ = current_byte;
+  }
+}
+
+// Like GenerateBits(), but unrolls its main loop for higher performance.
+
+template <class Generator>
+void GenerateBitsUnrolled(uint8_t* bitmap, int64_t start_offset, int64_t length,
+                          Generator&& g) {
+  static_assert(std::is_same<decltype(std::declval<Generator>()()), bool>::value,
+                "Functor passed to GenerateBitsUnrolled must return bool");
+
+  if (length == 0) {
+    return;
+  }
+  uint8_t current_byte;
+  uint8_t* cur = bitmap + start_offset / 8;
+  const uint64_t start_bit_offset = start_offset % 8;
+  uint8_t bit_mask = bit_util::kBitmask[start_bit_offset];
+  int64_t remaining = length;
+
+  if (bit_mask != 0x01) {
+    current_byte = *cur & bit_util::kPrecedingBitmask[start_bit_offset];
+    while (bit_mask != 0 && remaining > 0) {
+      current_byte |= g() * bit_mask;
+      bit_mask = static_cast<uint8_t>(bit_mask << 1);
+      --remaining;
+    }
+    *cur++ = current_byte;
+  }
+
+  int64_t remaining_bytes = remaining / 8;
+  uint8_t out_results[8];
+  while (remaining_bytes-- > 0) {
+    for (int i = 0; i < 8; ++i) {
+      out_results[i] = g();
+    }
+    *cur++ = static_cast<uint8_t>(out_results[0] | out_results[1] << 1 |
+                                  out_results[2] << 2 | out_results[3] << 3 |
+                                  out_results[4] << 4 | out_results[5] << 5 |
+                                  out_results[6] << 6 | out_results[7] << 7);
+  }
+
+  int64_t remaining_bits = remaining % 8;
+  if (remaining_bits) {
+    current_byte = 0;
+    bit_mask = 0x01;
+    while (remaining_bits-- > 0) {
+      current_byte |= g() * bit_mask;
+      bit_mask = static_cast<uint8_t>(bit_mask << 1);
+    }
+    *cur++ = current_byte;
+  }
+}
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bitmap_reader.h

@@ -0,0 +1,273 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+
+#include "arrow/buffer.h"
+#include "arrow/util/bit_util.h"
+#include "arrow/util/endian.h"
+#include "arrow/util/macros.h"
+
+namespace arrow {
+namespace internal {
+
+class BitmapReader {
+ public:
+  BitmapReader(const uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(bitmap), position_(0), length_(length) {
+    current_byte_ = 0;
+    byte_offset_ = start_offset / 8;
+    bit_offset_ = start_offset % 8;
+    if (length > 0) {
+      current_byte_ = bitmap[byte_offset_];
+    }
+  }
+
+  bool IsSet() const { return (current_byte_ & (1 << bit_offset_)) != 0; }
+
+  bool IsNotSet() const { return (current_byte_ & (1 << bit_offset_)) == 0; }
+
+  void Next() {
+    ++bit_offset_;
+    ++position_;
+    if (ARROW_PREDICT_FALSE(bit_offset_ == 8)) {
+      bit_offset_ = 0;
+      ++byte_offset_;
+      if (ARROW_PREDICT_TRUE(position_ < length_)) {
+        current_byte_ = bitmap_[byte_offset_];
+      }
+    }
+  }
+
+  int64_t position() const { return position_; }
+
+  int64_t length() const { return length_; }
+
+ private:
+  const uint8_t* bitmap_;
+  int64_t position_;
+  int64_t length_;
+
+  uint8_t current_byte_;
+  int64_t byte_offset_;
+  int64_t bit_offset_;
+};
+
+// XXX Cannot name it BitmapWordReader because the name is already used
+// in bitmap_ops.cc
+
+class BitmapUInt64Reader {
+ public:
+  BitmapUInt64Reader(const uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(util::MakeNonNull(bitmap) + start_offset / 8),
+        num_carry_bits_(8 - start_offset % 8),
+        length_(length),
+        remaining_length_(length_),
+        carry_bits_(0) {
+    if (length_ > 0) {
+      // Load carry bits from the first byte's MSBs
+      if (length_ >= num_carry_bits_) {
+        carry_bits_ =
+            LoadPartialWord(static_cast<int8_t>(8 - num_carry_bits_), num_carry_bits_);
+      } else {
+        carry_bits_ = LoadPartialWord(static_cast<int8_t>(8 - num_carry_bits_), length_);
+      }
+    }
+  }
+
+  uint64_t NextWord() {
+    if (ARROW_PREDICT_TRUE(remaining_length_ >= 64 + num_carry_bits_)) {
+      // We can load a full word
+      uint64_t next_word = LoadFullWord();
+      // Carry bits come first, then the (64 - num_carry_bits_) LSBs from next_word
+      uint64_t word = carry_bits_ | (next_word << num_carry_bits_);
+      carry_bits_ = next_word >> (64 - num_carry_bits_);
+      remaining_length_ -= 64;
+      return word;
+    } else if (remaining_length_ > num_carry_bits_) {
+      // We can load a partial word
+      uint64_t next_word =
+          LoadPartialWord(/*bit_offset=*/0, remaining_length_ - num_carry_bits_);
+      uint64_t word = carry_bits_ | (next_word << num_carry_bits_);
+      carry_bits_ = next_word >> (64 - num_carry_bits_);
+      remaining_length_ = std::max<int64_t>(remaining_length_ - 64, 0);
+      return word;
+    } else {
+      remaining_length_ = 0;
+      return carry_bits_;
+    }
+  }
+
+  int64_t position() const { return length_ - remaining_length_; }
+
+  int64_t length() const { return length_; }
+
+ private:
+  uint64_t LoadFullWord() {
+    uint64_t word;
+    memcpy(&word, bitmap_, 8);
+    bitmap_ += 8;
+    return bit_util::ToLittleEndian(word);
+  }
+
+  uint64_t LoadPartialWord(int8_t bit_offset, int64_t num_bits) {
+    uint64_t word = 0;
+    const int64_t num_bytes = bit_util::BytesForBits(num_bits);
+    memcpy(&word, bitmap_, num_bytes);
+    bitmap_ += num_bytes;
+    return (bit_util::ToLittleEndian(word) >> bit_offset) &
+           bit_util::LeastSignificantBitMask(num_bits);
+  }
+
+  const uint8_t* bitmap_;
+  const int64_t num_carry_bits_;  // in [1, 8]
+  const int64_t length_;
+  int64_t remaining_length_;
+  uint64_t carry_bits_;
+};
+
+// BitmapWordReader here is faster than BitmapUInt64Reader (in bitmap_reader.h)
+// on sufficiently large inputs.  However, it has a larger prolog / epilog overhead
+// and should probably not be used for small bitmaps.
+
+template <typename Word, bool may_have_byte_offset = true>
+class BitmapWordReader {
+ public:
+  BitmapWordReader() = default;
+  BitmapWordReader(const uint8_t* bitmap, int64_t offset, int64_t length)
+      : offset_(static_cast<int64_t>(may_have_byte_offset) * (offset % 8)),
+        bitmap_(bitmap + offset / 8),
+        bitmap_end_(bitmap_ + bit_util::BytesForBits(offset_ + length)) {
+    // decrement word count by one as we may touch two adjacent words in one iteration
+    nwords_ = length / (sizeof(Word) * 8) - 1;
+    if (nwords_ < 0) {
+      nwords_ = 0;
+    }
+    trailing_bits_ = static_cast<int>(length - nwords_ * sizeof(Word) * 8);
+    trailing_bytes_ = static_cast<int>(bit_util::BytesForBits(trailing_bits_));
+
+    if (nwords_ > 0) {
+      current_data.word_ = load<Word>(bitmap_);
+    } else if (length > 0) {
+      current_data.epi.byte_ = load<uint8_t>(bitmap_);
+    }
+  }
+
+  Word NextWord() {
+    bitmap_ += sizeof(Word);
+    const Word next_word = load<Word>(bitmap_);
+    Word word = current_data.word_;
+    if (may_have_byte_offset && offset_) {
+      // combine two adjacent words into one word
+      // |<------ next ----->|<---- current ---->|
+      // +-------------+-----+-------------+-----+
+      // |     ---     |  A  |      B      | --- |
+      // +-------------+-----+-------------+-----+
+      //                  |         |       offset
+      //                  v         v
+      //               +-----+-------------+
+      //               |  A  |      B      |
+      //               +-----+-------------+
+      //               |<------ word ----->|
+      word >>= offset_;
+      word |= next_word << (sizeof(Word) * 8 - offset_);
+    }
+    current_data.word_ = next_word;
+    return word;
+  }
+
+  uint8_t NextTrailingByte(int& valid_bits) {
+    uint8_t byte;
+    assert(trailing_bits_ > 0);
+
+    if (trailing_bits_ <= 8) {
+      // last byte
+      valid_bits = trailing_bits_;
+      trailing_bits_ = 0;
+      byte = 0;
+      internal::BitmapReader reader(bitmap_, offset_, valid_bits);
+      for (int i = 0; i < valid_bits; ++i) {
+        byte >>= 1;
+        if (reader.IsSet()) {
+          byte |= 0x80;
+        }
+        reader.Next();
+      }
+      byte >>= (8 - valid_bits);
+    } else {
+      ++bitmap_;
+      const uint8_t next_byte = load<uint8_t>(bitmap_);
+      byte = current_data.epi.byte_;
+      if (may_have_byte_offset && offset_) {
+        byte >>= offset_;
+        byte |= next_byte << (8 - offset_);
+      }
+      current_data.epi.byte_ = next_byte;
+      trailing_bits_ -= 8;
+      trailing_bytes_--;
+      valid_bits = 8;
+    }
+    return byte;
+  }
+
+  int64_t words() const { return nwords_; }
+  int trailing_bytes() const { return trailing_bytes_; }
+
+ private:
+  int64_t offset_;
+  const uint8_t* bitmap_;
+
+  const uint8_t* bitmap_end_;
+  int64_t nwords_;
+  int trailing_bits_;
+  int trailing_bytes_;
+  union {
+    Word word_;
+    struct {
+#if ARROW_LITTLE_ENDIAN == 0
+      uint8_t padding_bytes_[sizeof(Word) - 1];
+#endif
+      uint8_t byte_;
+    } epi;
+  } current_data;
+
+  template <typename DType>
+  DType load(const uint8_t* bitmap) {
+    assert(bitmap + sizeof(DType) <= bitmap_end_);
+    return bit_util::ToLittleEndian(util::SafeLoadAs<DType>(bitmap));
+  }
+};
+
+/// \brief Index into a possibly nonexistent bitmap
+struct OptionalBitIndexer {
+  const uint8_t* bitmap;
+  const int64_t offset;
+
+  explicit OptionalBitIndexer(const uint8_t* buffer = NULLPTR, int64_t offset = 0)
+      : bitmap(buffer), offset(offset) {}
+
+  bool operator[](int64_t i) const {
+    return bitmap == NULLPTR || bit_util::GetBit(bitmap, offset + i);
+  }
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bitmap_writer.h

@@ -0,0 +1,286 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+#include <cstring>
+
+#include "arrow/util/bit_util.h"
+#include "arrow/util/endian.h"
+#include "arrow/util/macros.h"
+
+namespace arrow {
+namespace internal {
+
+class BitmapWriter {
+  // A sequential bitwise writer that preserves surrounding bit values.
+
+ public:
+  BitmapWriter(uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(bitmap), position_(0), length_(length) {
+    byte_offset_ = start_offset / 8;
+    bit_mask_ = bit_util::kBitmask[start_offset % 8];
+    if (length > 0) {
+      current_byte_ = bitmap[byte_offset_];
+    } else {
+      current_byte_ = 0;
+    }
+  }
+
+  void Set() { current_byte_ |= bit_mask_; }
+
+  void Clear() { current_byte_ &= bit_mask_ ^ 0xFF; }
+
+  void Next() {
+    bit_mask_ = static_cast<uint8_t>(bit_mask_ << 1);
+    ++position_;
+    if (bit_mask_ == 0) {
+      // Finished this byte, need advancing
+      bit_mask_ = 0x01;
+      bitmap_[byte_offset_++] = current_byte_;
+      if (ARROW_PREDICT_TRUE(position_ < length_)) {
+        current_byte_ = bitmap_[byte_offset_];
+      }
+    }
+  }
+
+  void Finish() {
+    // Store current byte if we didn't went past bitmap storage
+    if (length_ > 0 && (bit_mask_ != 0x01 || position_ < length_)) {
+      bitmap_[byte_offset_] = current_byte_;
+    }
+  }
+
+  int64_t position() const { return position_; }
+
+ private:
+  uint8_t* bitmap_;
+  int64_t position_;
+  int64_t length_;
+
+  uint8_t current_byte_;
+  uint8_t bit_mask_;
+  int64_t byte_offset_;
+};
+
+class FirstTimeBitmapWriter {
+  // Like BitmapWriter, but any bit values *following* the bits written
+  // might be clobbered.  It is hence faster than BitmapWriter, and can
+  // also avoid false positives with Valgrind.
+
+ public:
+  FirstTimeBitmapWriter(uint8_t* bitmap, int64_t start_offset, int64_t length)
+      : bitmap_(bitmap), position_(0), length_(length) {
+    current_byte_ = 0;
+    byte_offset_ = start_offset / 8;
+    bit_mask_ = bit_util::kBitmask[start_offset % 8];
+    if (length > 0) {
+      current_byte_ =
+          bitmap[byte_offset_] & bit_util::kPrecedingBitmask[start_offset % 8];
+    } else {
+      current_byte_ = 0;
+    }
+  }
+
+  /// Appends number_of_bits from word to valid_bits and valid_bits_offset.
+  ///
+  /// \param[in] word The LSB bitmap to append. Any bits past number_of_bits are assumed
+  ///            to be unset (i.e. 0).
+  /// \param[in] number_of_bits The number of bits to append from word.
+  void AppendWord(uint64_t word, int64_t number_of_bits) {
+    if (ARROW_PREDICT_FALSE(number_of_bits == 0)) {
+      return;
+    }
+
+    // Location that the first byte needs to be written to.
+    uint8_t* append_position = bitmap_ + byte_offset_;
+
+    // Update state variables except for current_byte_ here.
+    position_ += number_of_bits;
+    int64_t bit_offset = bit_util::CountTrailingZeros(static_cast<uint32_t>(bit_mask_));
+    bit_mask_ = bit_util::kBitmask[(bit_offset + number_of_bits) % 8];
+    byte_offset_ += (bit_offset + number_of_bits) / 8;
+
+    if (bit_offset != 0) {
+      // We are in the middle of the byte. This code updates the byte and shifts
+      // bits appropriately within word so it can be memcpy'd below.
+      int64_t bits_to_carry = 8 - bit_offset;
+      // Carry over bits from word to current_byte_. We assume any extra bits in word
+      // unset so no additional accounting is needed for when number_of_bits <
+      // bits_to_carry.
+      current_byte_ |= (word & bit_util::kPrecedingBitmask[bits_to_carry]) << bit_offset;
+      // Check if everything is transferred into current_byte_.
+      if (ARROW_PREDICT_FALSE(number_of_bits < bits_to_carry)) {
+        return;
+      }
+      *append_position = current_byte_;
+      append_position++;
+      // Move the carry bits off of word.
+      word = word >> bits_to_carry;
+      number_of_bits -= bits_to_carry;
+    }
+    word = bit_util::ToLittleEndian(word);
+    int64_t bytes_for_word = ::arrow::bit_util::BytesForBits(number_of_bits);
+    std::memcpy(append_position, &word, bytes_for_word);
+    // At this point, the previous current_byte_ has been written to bitmap_.
+    // The new current_byte_ is either the last relevant byte in 'word'
+    // or cleared if the new position is byte aligned (i.e. a fresh byte).
+    if (bit_mask_ == 0x1) {
+      current_byte_ = 0;
+    } else {
+      current_byte_ = *(append_position + bytes_for_word - 1);
+    }
+  }
+
+  void Set() { current_byte_ |= bit_mask_; }
+
+  void Clear() {}
+
+  void Next() {
+    bit_mask_ = static_cast<uint8_t>(bit_mask_ << 1);
+    ++position_;
+    if (bit_mask_ == 0) {
+      // Finished this byte, need advancing
+      bit_mask_ = 0x01;
+      bitmap_[byte_offset_++] = current_byte_;
+      current_byte_ = 0;
+    }
+  }
+
+  void Finish() {
+    // Store current byte if we didn't went go bitmap storage
+    if (length_ > 0 && (bit_mask_ != 0x01 || position_ < length_)) {
+      bitmap_[byte_offset_] = current_byte_;
+    }
+  }
+
+  int64_t position() const { return position_; }
+
+ private:
+  uint8_t* bitmap_;
+  int64_t position_;
+  int64_t length_;
+
+  uint8_t current_byte_;
+  uint8_t bit_mask_;
+  int64_t byte_offset_;
+};
+
+template <typename Word, bool may_have_byte_offset = true>
+class BitmapWordWriter {
+ public:
+  BitmapWordWriter() = default;
+  BitmapWordWriter(uint8_t* bitmap, int64_t offset, int64_t length)
+      : offset_(static_cast<int64_t>(may_have_byte_offset) * (offset % 8)),
+        bitmap_(bitmap + offset / 8),
+        bitmap_end_(bitmap_ + bit_util::BytesForBits(offset_ + length)),
+        mask_((1U << offset_) - 1) {
+    if (offset_) {
+      if (length >= static_cast<int>(sizeof(Word) * 8)) {
+        current_data.word_ = load<Word>(bitmap_);
+      } else if (length > 0) {
+        current_data.epi.byte_ = load<uint8_t>(bitmap_);
+      }
+    }
+  }
+
+  void PutNextWord(Word word) {
+    if (may_have_byte_offset && offset_) {
+      // split one word into two adjacent words, don't touch unused bits
+      //               |<------ word ----->|
+      //               +-----+-------------+
+      //               |  A  |      B      |
+      //               +-----+-------------+
+      //                  |         |
+      //                  v         v       offset
+      // +-------------+-----+-------------+-----+
+      // |     ---     |  A  |      B      | --- |
+      // +-------------+-----+-------------+-----+
+      // |<------ next ----->|<---- current ---->|
+      word = (word << offset_) | (word >> (sizeof(Word) * 8 - offset_));
+      Word next_word = load<Word>(bitmap_ + sizeof(Word));
+      current_data.word_ = (current_data.word_ & mask_) | (word & ~mask_);
+      next_word = (next_word & ~mask_) | (word & mask_);
+      store<Word>(bitmap_, current_data.word_);
+      store<Word>(bitmap_ + sizeof(Word), next_word);
+      current_data.word_ = next_word;
+    } else {
+      store<Word>(bitmap_, word);
+    }
+    bitmap_ += sizeof(Word);
+  }
+
+  void PutNextTrailingByte(uint8_t byte, int valid_bits) {
+    if (valid_bits == 8) {
+      if (may_have_byte_offset && offset_) {
+        byte = (byte << offset_) | (byte >> (8 - offset_));
+        uint8_t next_byte = load<uint8_t>(bitmap_ + 1);
+        current_data.epi.byte_ = (current_data.epi.byte_ & mask_) | (byte & ~mask_);
+        next_byte = (next_byte & ~mask_) | (byte & mask_);
+        store<uint8_t>(bitmap_, current_data.epi.byte_);
+        store<uint8_t>(bitmap_ + 1, next_byte);
+        current_data.epi.byte_ = next_byte;
+      } else {
+        store<uint8_t>(bitmap_, byte);
+      }
+      ++bitmap_;
+    } else {
+      assert(valid_bits > 0);
+      assert(valid_bits < 8);
+      assert(bitmap_ + bit_util::BytesForBits(offset_ + valid_bits) <= bitmap_end_);
+      internal::BitmapWriter writer(bitmap_, offset_, valid_bits);
+      for (int i = 0; i < valid_bits; ++i) {
+        (byte & 0x01) ? writer.Set() : writer.Clear();
+        writer.Next();
+        byte >>= 1;
+      }
+      writer.Finish();
+    }
+  }
+
+ private:
+  int64_t offset_;
+  uint8_t* bitmap_;
+
+  const uint8_t* bitmap_end_;
+  uint64_t mask_;
+  union {
+    Word word_;
+    struct {
+#if ARROW_LITTLE_ENDIAN == 0
+      uint8_t padding_bytes_[sizeof(Word) - 1];
+#endif
+      uint8_t byte_;
+    } epi;
+  } current_data;
+
+  template <typename DType>
+  DType load(const uint8_t* bitmap) {
+    assert(bitmap + sizeof(DType) <= bitmap_end_);
+    return bit_util::ToLittleEndian(util::SafeLoadAs<DType>(bitmap));
+  }
+
+  template <typename DType>
+  void store(uint8_t* bitmap, DType data) {
+    assert(bitmap + sizeof(DType) <= bitmap_end_);
+    util::SafeStore(bitmap, bit_util::FromLittleEndian(data));
+  }
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bitset_stack.h

@@ -0,0 +1,89 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <algorithm>
+#include <array>
+#include <bitset>
+#include <cassert>
+#include <cstdint>
+#include <cstring>
+#include <memory>
+#include <string>
+#include <string_view>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "arrow/buffer.h"
+#include "arrow/memory_pool.h"
+#include "arrow/result.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/bit_util.h"
+#include "arrow/util/compare.h"
+#include "arrow/util/functional.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/string_builder.h"
+#include "arrow/util/type_traits.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+/// \brief Store a stack of bitsets efficiently. The top bitset may be
+/// accessed and its bits may be modified, but it may not be resized.
+class BitsetStack {
+ public:
+  using reference = typename std::vector<bool>::reference;
+
+  /// \brief push a bitset onto the stack
+  /// \param size number of bits in the next bitset
+  /// \param value initial value for bits in the pushed bitset
+  void Push(int size, bool value) {
+    offsets_.push_back(bit_count());
+    bits_.resize(bit_count() + size, value);
+  }
+
+  /// \brief number of bits in the bitset at the top of the stack
+  int TopSize() const {
+    if (offsets_.size() == 0) return 0;
+    return bit_count() - offsets_.back();
+  }
+
+  /// \brief pop a bitset off the stack
+  void Pop() {
+    bits_.resize(offsets_.back());
+    offsets_.pop_back();
+  }
+
+  /// \brief get the value of a bit in the top bitset
+  /// \param i index of the bit to access
+  bool operator[](int i) const { return bits_[offsets_.back() + i]; }
+
+  /// \brief get a mutable reference to a bit in the top bitset
+  /// \param i index of the bit to access
+  reference operator[](int i) { return bits_[offsets_.back() + i]; }
+
+ private:
+  int bit_count() const { return static_cast<int>(bits_.size()); }
+  std::vector<bool> bits_;
+  std::vector<int> offsets_;
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bpacking.h

@@ -0,0 +1,34 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include "arrow/util/endian.h"
+#include "arrow/util/visibility.h"
+
+#include <stdint.h>
+
+namespace arrow {
+namespace internal {
+
+ARROW_EXPORT
+int unpack32(const uint32_t* in, uint32_t* out, int batch_size, int num_bits);
+ARROW_EXPORT
+int unpack64(const uint8_t* in, uint64_t* out, int batch_size, int num_bits);
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bpacking_avx2.h

@@ -0,0 +1,28 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <stdint.h>
+
+namespace arrow {
+namespace internal {
+
+int unpack32_avx2(const uint32_t* in, uint32_t* out, int batch_size, int num_bits);
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/bpacking_avx512.h

@@ -0,0 +1,28 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <stdint.h>
+
+namespace arrow {
+namespace internal {
+
+int unpack32_avx512(const uint32_t* in, uint32_t* out, int batch_size, int num_bits);
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/byte_size.h

@@ -0,0 +1,88 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+
+#include "arrow/type_fwd.h"
+
+namespace arrow {
+
+namespace util {
+
+/// \brief The sum of bytes in each buffer referenced by the array
+///
+/// Note: An array may only reference a portion of a buffer.
+///       This method will overestimate in this case and return the
+///       byte size of the entire buffer.
+/// Note: If a buffer is referenced multiple times then it will
+///       only be counted once.
+ARROW_EXPORT int64_t TotalBufferSize(const ArrayData& array_data);
+/// \brief The sum of bytes in each buffer referenced by the array
+/// \see TotalBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT int64_t TotalBufferSize(const Array& array);
+/// \brief The sum of bytes in each buffer referenced by the array
+/// \see TotalBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT int64_t TotalBufferSize(const ChunkedArray& chunked_array);
+/// \brief The sum of bytes in each buffer referenced by the batch
+/// \see TotalBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT int64_t TotalBufferSize(const RecordBatch& record_batch);
+/// \brief The sum of bytes in each buffer referenced by the table
+/// \see TotalBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT int64_t TotalBufferSize(const Table& table);
+
+/// \brief Calculate the buffer ranges referenced by the array
+///
+/// These ranges will take into account array offsets
+///
+/// The ranges may contain duplicates
+///
+/// Dictionary arrays will ignore the offset of their containing array
+///
+/// The return value will be a struct array corresponding to the schema:
+/// schema({field("start", uint64()), field("offset", uint64()), field("length",
+/// uint64()))
+ARROW_EXPORT Result<std::shared_ptr<Array>> ReferencedRanges(const ArrayData& array_data);
+
+/// \brief Returns the sum of bytes from all buffer ranges referenced
+///
+/// Unlike TotalBufferSize this method will account for array
+/// offsets.
+///
+/// If buffers are shared between arrays then the shared
+/// portion will be counted multiple times.
+///
+/// Dictionary arrays will always be counted in their entirety
+/// even if the array only references a portion of the dictionary.
+ARROW_EXPORT Result<int64_t> ReferencedBufferSize(const ArrayData& array_data);
+/// \brief Returns the sum of bytes from all buffer ranges referenced
+/// \see ReferencedBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT Result<int64_t> ReferencedBufferSize(const Array& array_data);
+/// \brief Returns the sum of bytes from all buffer ranges referenced
+/// \see ReferencedBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT Result<int64_t> ReferencedBufferSize(const ChunkedArray& array_data);
+/// \brief Returns the sum of bytes from all buffer ranges referenced
+/// \see ReferencedBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT Result<int64_t> ReferencedBufferSize(const RecordBatch& array_data);
+/// \brief Returns the sum of bytes from all buffer ranges referenced
+/// \see ReferencedBufferSize(const ArrayData& array_data) for details
+ARROW_EXPORT Result<int64_t> ReferencedBufferSize(const Table& array_data);
+
+}  // namespace util
+
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/compression.h

@@ -0,0 +1,241 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+#include <limits>
+#include <memory>
+#include <optional>
+#include <string>
+
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/util/type_fwd.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace util {
+
+constexpr int kUseDefaultCompressionLevel = std::numeric_limits<int>::min();
+
+/// \brief Streaming compressor interface
+///
+class ARROW_EXPORT Compressor {
+ public:
+  virtual ~Compressor() = default;
+
+  struct CompressResult {
+    int64_t bytes_read;
+    int64_t bytes_written;
+  };
+  struct FlushResult {
+    int64_t bytes_written;
+    bool should_retry;
+  };
+  struct EndResult {
+    int64_t bytes_written;
+    bool should_retry;
+  };
+
+  /// \brief Compress some input.
+  ///
+  /// If bytes_read is 0 on return, then a larger output buffer should be supplied.
+  virtual Result<CompressResult> Compress(int64_t input_len, const uint8_t* input,
+                                          int64_t output_len, uint8_t* output) = 0;
+
+  /// \brief Flush part of the compressed output.
+  ///
+  /// If should_retry is true on return, Flush() should be called again
+  /// with a larger buffer.
+  virtual Result<FlushResult> Flush(int64_t output_len, uint8_t* output) = 0;
+
+  /// \brief End compressing, doing whatever is necessary to end the stream.
+  ///
+  /// If should_retry is true on return, End() should be called again
+  /// with a larger buffer.  Otherwise, the Compressor should not be used anymore.
+  ///
+  /// End() implies Flush().
+  virtual Result<EndResult> End(int64_t output_len, uint8_t* output) = 0;
+
+  // XXX add methods for buffer size heuristics?
+};
+
+/// \brief Streaming decompressor interface
+///
+class ARROW_EXPORT Decompressor {
+ public:
+  virtual ~Decompressor() = default;
+
+  struct DecompressResult {
+    // XXX is need_more_output necessary? (Brotli?)
+    int64_t bytes_read;
+    int64_t bytes_written;
+    bool need_more_output;
+  };
+
+  /// \brief Decompress some input.
+  ///
+  /// If need_more_output is true on return, a larger output buffer needs
+  /// to be supplied.
+  virtual Result<DecompressResult> Decompress(int64_t input_len, const uint8_t* input,
+                                              int64_t output_len, uint8_t* output) = 0;
+
+  /// \brief Return whether the compressed stream is finished.
+  ///
+  /// This is a heuristic.  If true is returned, then it is guaranteed
+  /// that the stream is finished.  If false is returned, however, it may
+  /// simply be that the underlying library isn't able to provide the information.
+  virtual bool IsFinished() = 0;
+
+  /// \brief Reinitialize decompressor, making it ready for a new compressed stream.
+  virtual Status Reset() = 0;
+
+  // XXX add methods for buffer size heuristics?
+};
+
+/// \brief Compression codec options
+class ARROW_EXPORT CodecOptions {
+ public:
+  explicit CodecOptions(int compression_level = kUseDefaultCompressionLevel)
+      : compression_level(compression_level) {}
+
+  virtual ~CodecOptions() = default;
+
+  int compression_level;
+};
+
+// ----------------------------------------------------------------------
+// GZip codec options implementation
+
+enum class GZipFormat {
+  ZLIB,
+  DEFLATE,
+  GZIP,
+};
+
+class ARROW_EXPORT GZipCodecOptions : public CodecOptions {
+ public:
+  GZipFormat gzip_format = GZipFormat::GZIP;
+  std::optional<int> window_bits;
+};
+
+// ----------------------------------------------------------------------
+// brotli codec options implementation
+
+class ARROW_EXPORT BrotliCodecOptions : public CodecOptions {
+ public:
+  std::optional<int> window_bits;
+};
+
+/// \brief Compression codec
+class ARROW_EXPORT Codec {
+ public:
+  virtual ~Codec() = default;
+
+  /// \brief Return special value to indicate that a codec implementation
+  /// should use its default compression level
+  static int UseDefaultCompressionLevel();
+
+  /// \brief Return a string name for compression type
+  static const std::string& GetCodecAsString(Compression::type t);
+
+  /// \brief Return compression type for name (all lower case)
+  static Result<Compression::type> GetCompressionType(const std::string& name);
+
+  /// \brief Create a codec for the given compression algorithm with CodecOptions
+  static Result<std::unique_ptr<Codec>> Create(
+      Compression::type codec, const CodecOptions& codec_options = CodecOptions{});
+
+  /// \brief Create a codec for the given compression algorithm
+  static Result<std::unique_ptr<Codec>> Create(Compression::type codec,
+                                               int compression_level);
+
+  /// \brief Return true if support for indicated codec has been enabled
+  static bool IsAvailable(Compression::type codec);
+
+  /// \brief Return true if indicated codec supports setting a compression level
+  static bool SupportsCompressionLevel(Compression::type codec);
+
+  /// \brief Return the smallest supported compression level for the codec
+  /// Note: This function creates a temporary Codec instance
+  static Result<int> MinimumCompressionLevel(Compression::type codec);
+
+  /// \brief Return the largest supported compression level for the codec
+  /// Note: This function creates a temporary Codec instance
+  static Result<int> MaximumCompressionLevel(Compression::type codec);
+
+  /// \brief Return the default compression level
+  /// Note: This function creates a temporary Codec instance
+  static Result<int> DefaultCompressionLevel(Compression::type codec);
+
+  /// \brief Return the smallest supported compression level
+  virtual int minimum_compression_level() const = 0;
+
+  /// \brief Return the largest supported compression level
+  virtual int maximum_compression_level() const = 0;
+
+  /// \brief Return the default compression level
+  virtual int default_compression_level() const = 0;
+
+  /// \brief One-shot decompression function
+  ///
+  /// output_buffer_len must be correct and therefore be obtained in advance.
+  /// The actual decompressed length is returned.
+  ///
+  /// \note One-shot decompression is not always compatible with streaming
+  /// compression.  Depending on the codec (e.g. LZ4), different formats may
+  /// be used.
+  virtual Result<int64_t> Decompress(int64_t input_len, const uint8_t* input,
+                                     int64_t output_buffer_len,
+                                     uint8_t* output_buffer) = 0;
+
+  /// \brief One-shot compression function
+  ///
+  /// output_buffer_len must first have been computed using MaxCompressedLen().
+  /// The actual compressed length is returned.
+  ///
+  /// \note One-shot compression is not always compatible with streaming
+  /// decompression.  Depending on the codec (e.g. LZ4), different formats may
+  /// be used.
+  virtual Result<int64_t> Compress(int64_t input_len, const uint8_t* input,
+                                   int64_t output_buffer_len, uint8_t* output_buffer) = 0;
+
+  virtual int64_t MaxCompressedLen(int64_t input_len, const uint8_t* input) = 0;
+
+  /// \brief Create a streaming compressor instance
+  virtual Result<std::shared_ptr<Compressor>> MakeCompressor() = 0;
+
+  /// \brief Create a streaming compressor instance
+  virtual Result<std::shared_ptr<Decompressor>> MakeDecompressor() = 0;
+
+  /// \brief This Codec's compression type
+  virtual Compression::type compression_type() const = 0;
+
+  /// \brief The name of this Codec's compression type
+  const std::string& name() const { return GetCodecAsString(compression_type()); }
+
+  /// \brief This Codec's compression level, if applicable
+  virtual int compression_level() const { return UseDefaultCompressionLevel(); }
+
+ private:
+  /// \brief Initializes the codec's resources.
+  virtual Status Init();
+};
+
+}  // namespace util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/converter.h

@@ -0,0 +1,411 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "arrow/array.h"
+#include "arrow/chunked_array.h"
+#include "arrow/status.h"
+#include "arrow/type.h"
+#include "arrow/type_traits.h"
+#include "arrow/util/checked_cast.h"
+#include "arrow/visit_type_inline.h"
+
+namespace arrow {
+namespace internal {
+
+template <typename BaseConverter, template <typename...> class ConverterTrait>
+static Result<std::unique_ptr<BaseConverter>> MakeConverter(
+    std::shared_ptr<DataType> type, typename BaseConverter::OptionsType options,
+    MemoryPool* pool);
+
+template <typename Input, typename Options>
+class Converter {
+ public:
+  using Self = Converter<Input, Options>;
+  using InputType = Input;
+  using OptionsType = Options;
+
+  virtual ~Converter() = default;
+
+  Status Construct(std::shared_ptr<DataType> type, OptionsType options,
+                   MemoryPool* pool) {
+    type_ = std::move(type);
+    options_ = std::move(options);
+    return Init(pool);
+  }
+
+  virtual Status Append(InputType value) { return Status::NotImplemented("Append"); }
+
+  virtual Status Extend(InputType values, int64_t size, int64_t offset = 0) {
+    return Status::NotImplemented("Extend");
+  }
+
+  virtual Status ExtendMasked(InputType values, InputType mask, int64_t size,
+                              int64_t offset = 0) {
+    return Status::NotImplemented("ExtendMasked");
+  }
+
+  const std::shared_ptr<ArrayBuilder>& builder() const { return builder_; }
+
+  const std::shared_ptr<DataType>& type() const { return type_; }
+
+  OptionsType options() const { return options_; }
+
+  bool may_overflow() const { return may_overflow_; }
+
+  bool rewind_on_overflow() const { return rewind_on_overflow_; }
+
+  virtual Status Reserve(int64_t additional_capacity) {
+    return builder_->Reserve(additional_capacity);
+  }
+
+  Status AppendNull() { return builder_->AppendNull(); }
+
+  virtual Result<std::shared_ptr<Array>> ToArray() { return builder_->Finish(); }
+
+  virtual Result<std::shared_ptr<Array>> ToArray(int64_t length) {
+    ARROW_ASSIGN_OR_RAISE(auto arr, this->ToArray());
+    return arr->Slice(0, length);
+  }
+
+  virtual Result<std::shared_ptr<ChunkedArray>> ToChunkedArray() {
+    ARROW_ASSIGN_OR_RAISE(auto array, ToArray());
+    std::vector<std::shared_ptr<Array>> chunks = {std::move(array)};
+    return std::make_shared<ChunkedArray>(chunks);
+  }
+
+ protected:
+  virtual Status Init(MemoryPool* pool) { return Status::OK(); }
+
+  std::shared_ptr<DataType> type_;
+  std::shared_ptr<ArrayBuilder> builder_;
+  OptionsType options_;
+  bool may_overflow_ = false;
+  bool rewind_on_overflow_ = false;
+};
+
+template <typename ArrowType, typename BaseConverter>
+class PrimitiveConverter : public BaseConverter {
+ public:
+  using BuilderType = typename TypeTraits<ArrowType>::BuilderType;
+
+ protected:
+  Status Init(MemoryPool* pool) override {
+    this->builder_ = std::make_shared<BuilderType>(this->type_, pool);
+    // Narrow variable-sized binary types may overflow
+    this->may_overflow_ = is_binary_like(this->type_->id());
+    primitive_type_ = checked_cast<const ArrowType*>(this->type_.get());
+    primitive_builder_ = checked_cast<BuilderType*>(this->builder_.get());
+    return Status::OK();
+  }
+
+  const ArrowType* primitive_type_;
+  BuilderType* primitive_builder_;
+};
+
+template <typename ArrowType, typename BaseConverter,
+          template <typename...> class ConverterTrait>
+class ListConverter : public BaseConverter {
+ public:
+  using BuilderType = typename TypeTraits<ArrowType>::BuilderType;
+  using ConverterType = typename ConverterTrait<ArrowType>::type;
+
+ protected:
+  Status Init(MemoryPool* pool) override {
+    list_type_ = checked_cast<const ArrowType*>(this->type_.get());
+    ARROW_ASSIGN_OR_RAISE(value_converter_,
+                          (MakeConverter<BaseConverter, ConverterTrait>(
+                              list_type_->value_type(), this->options_, pool)));
+    this->builder_ =
+        std::make_shared<BuilderType>(pool, value_converter_->builder(), this->type_);
+    list_builder_ = checked_cast<BuilderType*>(this->builder_.get());
+    // Narrow list types may overflow
+    this->may_overflow_ = this->rewind_on_overflow_ =
+        sizeof(typename ArrowType::offset_type) < sizeof(int64_t);
+    return Status::OK();
+  }
+
+  const ArrowType* list_type_;
+  BuilderType* list_builder_;
+  std::unique_ptr<BaseConverter> value_converter_;
+};
+
+template <typename BaseConverter, template <typename...> class ConverterTrait>
+class StructConverter : public BaseConverter {
+ public:
+  using ConverterType = typename ConverterTrait<StructType>::type;
+
+  Status Reserve(int64_t additional_capacity) override {
+    ARROW_RETURN_NOT_OK(this->builder_->Reserve(additional_capacity));
+    for (const auto& child : children_) {
+      ARROW_RETURN_NOT_OK(child->Reserve(additional_capacity));
+    }
+    return Status::OK();
+  }
+
+ protected:
+  Status Init(MemoryPool* pool) override {
+    std::unique_ptr<BaseConverter> child_converter;
+    std::vector<std::shared_ptr<ArrayBuilder>> child_builders;
+
+    struct_type_ = checked_cast<const StructType*>(this->type_.get());
+    for (const auto& field : struct_type_->fields()) {
+      ARROW_ASSIGN_OR_RAISE(child_converter,
+                            (MakeConverter<BaseConverter, ConverterTrait>(
+                                field->type(), this->options_, pool)));
+      this->may_overflow_ |= child_converter->may_overflow();
+      this->rewind_on_overflow_ = this->may_overflow_;
+      child_builders.push_back(child_converter->builder());
+      children_.push_back(std::move(child_converter));
+    }
+
+    this->builder_ =
+        std::make_shared<StructBuilder>(this->type_, pool, std::move(child_builders));
+    struct_builder_ = checked_cast<StructBuilder*>(this->builder_.get());
+
+    return Status::OK();
+  }
+
+  const StructType* struct_type_;
+  StructBuilder* struct_builder_;
+  std::vector<std::unique_ptr<BaseConverter>> children_;
+};
+
+template <typename ValueType, typename BaseConverter>
+class DictionaryConverter : public BaseConverter {
+ public:
+  using BuilderType = DictionaryBuilder<ValueType>;
+
+ protected:
+  Status Init(MemoryPool* pool) override {
+    std::unique_ptr<ArrayBuilder> builder;
+    ARROW_RETURN_NOT_OK(MakeDictionaryBuilder(pool, this->type_, NULLPTR, &builder));
+    this->builder_ = std::move(builder);
+    this->may_overflow_ = false;
+    dict_type_ = checked_cast<const DictionaryType*>(this->type_.get());
+    value_type_ = checked_cast<const ValueType*>(dict_type_->value_type().get());
+    value_builder_ = checked_cast<BuilderType*>(this->builder_.get());
+    return Status::OK();
+  }
+
+  const DictionaryType* dict_type_;
+  const ValueType* value_type_;
+  BuilderType* value_builder_;
+};
+
+template <typename BaseConverter, template <typename...> class ConverterTrait>
+struct MakeConverterImpl {
+  template <typename T, typename ConverterType = typename ConverterTrait<T>::type>
+  Status Visit(const T&) {
+    out.reset(new ConverterType());
+    return out->Construct(std::move(type), std::move(options), pool);
+  }
+
+  Status Visit(const DictionaryType& t) {
+    switch (t.value_type()->id()) {
+#define DICTIONARY_CASE(TYPE)                                                       \
+  case TYPE::type_id:                                                               \
+    out = std::make_unique<                                                         \
+        typename ConverterTrait<DictionaryType>::template dictionary_type<TYPE>>(); \
+    break;
+      DICTIONARY_CASE(BooleanType);
+      DICTIONARY_CASE(Int8Type);
+      DICTIONARY_CASE(Int16Type);
+      DICTIONARY_CASE(Int32Type);
+      DICTIONARY_CASE(Int64Type);
+      DICTIONARY_CASE(UInt8Type);
+      DICTIONARY_CASE(UInt16Type);
+      DICTIONARY_CASE(UInt32Type);
+      DICTIONARY_CASE(UInt64Type);
+      DICTIONARY_CASE(FloatType);
+      DICTIONARY_CASE(DoubleType);
+      DICTIONARY_CASE(BinaryType);
+      DICTIONARY_CASE(StringType);
+      DICTIONARY_CASE(FixedSizeBinaryType);
+#undef DICTIONARY_CASE
+      default:
+        return Status::NotImplemented("DictionaryArray converter for type ", t.ToString(),
+                                      " not implemented");
+    }
+    return out->Construct(std::move(type), std::move(options), pool);
+  }
+
+  Status Visit(const DataType& t) { return Status::NotImplemented(t.name()); }
+
+  std::shared_ptr<DataType> type;
+  typename BaseConverter::OptionsType options;
+  MemoryPool* pool;
+  std::unique_ptr<BaseConverter> out;
+};
+
+template <typename BaseConverter, template <typename...> class ConverterTrait>
+static Result<std::unique_ptr<BaseConverter>> MakeConverter(
+    std::shared_ptr<DataType> type, typename BaseConverter::OptionsType options,
+    MemoryPool* pool) {
+  MakeConverterImpl<BaseConverter, ConverterTrait> visitor{
+      std::move(type), std::move(options), pool, NULLPTR};
+  ARROW_RETURN_NOT_OK(VisitTypeInline(*visitor.type, &visitor));
+  return std::move(visitor.out);
+}
+
+template <typename Converter>
+class Chunker {
+ public:
+  using InputType = typename Converter::InputType;
+
+  explicit Chunker(std::unique_ptr<Converter> converter)
+      : converter_(std::move(converter)) {}
+
+  Status Reserve(int64_t additional_capacity) {
+    ARROW_RETURN_NOT_OK(converter_->Reserve(additional_capacity));
+    reserved_ += additional_capacity;
+    return Status::OK();
+  }
+
+  Status AppendNull() {
+    auto status = converter_->AppendNull();
+    if (ARROW_PREDICT_FALSE(status.IsCapacityError())) {
+      if (converter_->builder()->length() == 0) {
+        // Builder length == 0 means the individual element is too large to append.
+        // In this case, no need to try again.
+        return status;
+      }
+      ARROW_RETURN_NOT_OK(FinishChunk());
+      return converter_->AppendNull();
+    }
+    ++length_;
+    return status;
+  }
+
+  Status Append(InputType value) {
+    auto status = converter_->Append(value);
+    if (ARROW_PREDICT_FALSE(status.IsCapacityError())) {
+      if (converter_->builder()->length() == 0) {
+        return status;
+      }
+      ARROW_RETURN_NOT_OK(FinishChunk());
+      return Append(value);
+    }
+    ++length_;
+    return status;
+  }
+
+  Status Extend(InputType values, int64_t size, int64_t offset = 0) {
+    while (offset < size) {
+      auto length_before = converter_->builder()->length();
+      auto status = converter_->Extend(values, size, offset);
+      auto length_after = converter_->builder()->length();
+      auto num_converted = length_after - length_before;
+
+      offset += num_converted;
+      length_ += num_converted;
+
+      if (status.IsCapacityError()) {
+        if (converter_->builder()->length() == 0) {
+          // Builder length == 0 means the individual element is too large to append.
+          // In this case, no need to try again.
+          return status;
+        } else if (converter_->rewind_on_overflow()) {
+          // The list-like and binary-like conversion paths may raise  a capacity error,
+          // we need to handle them differently. While the binary-like converters check
+          // the capacity before append/extend the list-like converters just check after
+          // append/extend. Thus depending on the implementation semantics we may need
+          // to rewind (slice) the output chunk by one.
+          length_ -= 1;
+          offset -= 1;
+        }
+        ARROW_RETURN_NOT_OK(FinishChunk());
+      } else if (!status.ok()) {
+        return status;
+      }
+    }
+    return Status::OK();
+  }
+
+  Status ExtendMasked(InputType values, InputType mask, int64_t size,
+                      int64_t offset = 0) {
+    while (offset < size) {
+      auto length_before = converter_->builder()->length();
+      auto status = converter_->ExtendMasked(values, mask, size, offset);
+      auto length_after = converter_->builder()->length();
+      auto num_converted = length_after - length_before;
+
+      offset += num_converted;
+      length_ += num_converted;
+
+      if (status.IsCapacityError()) {
+        if (converter_->builder()->length() == 0) {
+          // Builder length == 0 means the individual element is too large to append.
+          // In this case, no need to try again.
+          return status;
+        } else if (converter_->rewind_on_overflow()) {
+          // The list-like and binary-like conversion paths may raise  a capacity error,
+          // we need to handle them differently. While the binary-like converters check
+          // the capacity before append/extend the list-like converters just check after
+          // append/extend. Thus depending on the implementation semantics we may need
+          // to rewind (slice) the output chunk by one.
+          length_ -= 1;
+          offset -= 1;
+        }
+        ARROW_RETURN_NOT_OK(FinishChunk());
+      } else if (!status.ok()) {
+        return status;
+      }
+    }
+    return Status::OK();
+  }
+
+  Status FinishChunk() {
+    ARROW_ASSIGN_OR_RAISE(auto chunk, converter_->ToArray(length_));
+    chunks_.push_back(chunk);
+    // Reserve space for the remaining items.
+    // Besides being an optimization, it is also required if the converter's
+    // implementation relies on unsafe builder methods in converter->Append().
+    auto remaining = reserved_ - length_;
+    Reset();
+    return Reserve(remaining);
+  }
+
+  Result<std::shared_ptr<ChunkedArray>> ToChunkedArray() {
+    ARROW_RETURN_NOT_OK(FinishChunk());
+    return std::make_shared<ChunkedArray>(chunks_);
+  }
+
+ protected:
+  void Reset() {
+    converter_->builder()->Reset();
+    length_ = 0;
+    reserved_ = 0;
+  }
+
+  int64_t length_ = 0;
+  int64_t reserved_ = 0;
+  std::unique_ptr<Converter> converter_;
+  std::vector<std::shared_ptr<Array>> chunks_;
+};
+
+template <typename T>
+static Result<std::unique_ptr<Chunker<T>>> MakeChunker(std::unique_ptr<T> converter) {
+  return std::make_unique<Chunker<T>>(std::move(converter));
+}
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/cpu_info.h

@@ -0,0 +1,114 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// From Apache Impala (incubating) as of 2016-01-29. Pared down to a minimal
+// set of functions needed for Apache Arrow / Apache parquet-cpp
+
+#pragma once
+
+#include <cstdint>
+#include <memory>
+#include <string>
+
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+/// CpuInfo is an interface to query for cpu information at runtime.  The caller can
+/// ask for the sizes of the caches and what hardware features are supported.
+/// On Linux, this information is pulled from a couple of sys files (/proc/cpuinfo and
+/// /sys/devices)
+class ARROW_EXPORT CpuInfo {
+ public:
+  ~CpuInfo();
+
+  /// x86 features
+  static constexpr int64_t SSSE3 = (1LL << 0);
+  static constexpr int64_t SSE4_1 = (1LL << 1);
+  static constexpr int64_t SSE4_2 = (1LL << 2);
+  static constexpr int64_t POPCNT = (1LL << 3);
+  static constexpr int64_t AVX = (1LL << 4);
+  static constexpr int64_t AVX2 = (1LL << 5);
+  static constexpr int64_t AVX512F = (1LL << 6);
+  static constexpr int64_t AVX512CD = (1LL << 7);
+  static constexpr int64_t AVX512VL = (1LL << 8);
+  static constexpr int64_t AVX512DQ = (1LL << 9);
+  static constexpr int64_t AVX512BW = (1LL << 10);
+  static constexpr int64_t AVX512 = AVX512F | AVX512CD | AVX512VL | AVX512DQ | AVX512BW;
+  static constexpr int64_t BMI1 = (1LL << 11);
+  static constexpr int64_t BMI2 = (1LL << 12);
+
+  /// Arm features
+  static constexpr int64_t ASIMD = (1LL << 32);
+
+  /// Cache enums for L1 (data), L2 and L3
+  enum class CacheLevel { L1 = 0, L2, L3, Last = L3 };
+
+  /// CPU vendors
+  enum class Vendor { Unknown, Intel, AMD };
+
+  static const CpuInfo* GetInstance();
+
+  /// Returns all the flags for this cpu
+  int64_t hardware_flags() const;
+
+  /// Returns the number of cores (including hyper-threaded) on this machine.
+  int num_cores() const;
+
+  /// Returns the vendor of the cpu.
+  Vendor vendor() const;
+
+  /// Returns the model name of the cpu (e.g. Intel i7-2600)
+  const std::string& model_name() const;
+
+  /// Returns the size of the cache in KB at this cache level
+  int64_t CacheSize(CacheLevel level) const;
+
+  /// \brief Returns whether or not the given feature is enabled.
+  ///
+  /// IsSupported() is true iff IsDetected() is also true and the feature
+  /// wasn't disabled by the user (for example by setting the ARROW_USER_SIMD_LEVEL
+  /// environment variable).
+  bool IsSupported(int64_t flags) const;
+
+  /// Returns whether or not the given feature is available on the CPU.
+  bool IsDetected(int64_t flags) const;
+
+  /// Determine if the CPU meets the minimum CPU requirements and if not, issue an error
+  /// and terminate.
+  void VerifyCpuRequirements() const;
+
+  /// Toggle a hardware feature on and off.  It is not valid to turn on a feature
+  /// that the underlying hardware cannot support. This is useful for testing.
+  void EnableFeature(int64_t flag, bool enable);
+
+  bool HasEfficientBmi2() const {
+    // BMI2 (pext, pdep) is only efficient on Intel X86 processors.
+    return vendor() == Vendor::Intel && IsSupported(BMI2);
+  }
+
+ private:
+  CpuInfo();
+
+  struct Impl;
+  std::unique_ptr<Impl> impl_;
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/crc32.h

@@ -0,0 +1,36 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include <cstddef>
+#include <cstdint>
+
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+/// \brief Compute the CRC32 checksum of the given data
+///
+/// This function computes CRC32 with the polynomial 0x04C11DB7,
+/// as used in zlib and others (note this is different from CRC32C).
+/// To compute a running CRC32, pass the previous value in `prev`,
+/// otherwise `prev` should be 0.
+ARROW_EXPORT
+uint32_t crc32(uint32_t prev, const void* data, size_t length);
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/debug.h

@@ -0,0 +1,29 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace internal {
+
+ARROW_EXPORT
+void DebugTrap();
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/dispatch.h

@@ -0,0 +1,115 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <utility>
+#include <vector>
+
+#include "arrow/status.h"
+#include "arrow/util/cpu_info.h"
+
+namespace arrow {
+namespace internal {
+
+enum class DispatchLevel : int {
+  // These dispatch levels, corresponding to instruction set features,
+  // are sorted in increasing order of preference.
+  NONE = 0,
+  SSE4_2,
+  AVX2,
+  AVX512,
+  NEON,
+  MAX
+};
+
+/*
+  A facility for dynamic dispatch according to available DispatchLevel.
+
+  Typical use:
+
+    static void my_function_default(...);
+    static void my_function_avx2(...);
+
+    struct MyDynamicFunction {
+      using FunctionType = decltype(&my_function_default);
+
+      static std::vector<std::pair<DispatchLevel, FunctionType>> implementations() {
+        return {
+          { DispatchLevel::NONE, my_function_default }
+    #if defined(ARROW_HAVE_RUNTIME_AVX2)
+          , { DispatchLevel::AVX2, my_function_avx2 }
+    #endif
+        };
+      }
+    };
+
+    void my_function(...) {
+      static DynamicDispatch<MyDynamicFunction> dispatch;
+      return dispatch.func(...);
+    }
+*/
+template <typename DynamicFunction>
+class DynamicDispatch {
+ protected:
+  using FunctionType = typename DynamicFunction::FunctionType;
+  using Implementation = std::pair<DispatchLevel, FunctionType>;
+
+ public:
+  DynamicDispatch() { Resolve(DynamicFunction::implementations()); }
+
+  FunctionType func = {};
+
+ protected:
+  // Use the Implementation with the highest DispatchLevel
+  void Resolve(const std::vector<Implementation>& implementations) {
+    Implementation cur{DispatchLevel::NONE, {}};
+
+    for (const auto& impl : implementations) {
+      if (impl.first >= cur.first && IsSupported(impl.first)) {
+        // Higher (or same) level than current
+        cur = impl;
+      }
+    }
+
+    if (!cur.second) {
+      Status::Invalid("No appropriate implementation found").Abort();
+    }
+    func = cur.second;
+  }
+
+ private:
+  bool IsSupported(DispatchLevel level) const {
+    static const auto cpu_info = arrow::internal::CpuInfo::GetInstance();
+
+    switch (level) {
+      case DispatchLevel::NONE:
+        return true;
+      case DispatchLevel::SSE4_2:
+        return cpu_info->IsSupported(CpuInfo::SSE4_2);
+      case DispatchLevel::AVX2:
+        return cpu_info->IsSupported(CpuInfo::AVX2);
+      case DispatchLevel::AVX512:
+        return cpu_info->IsSupported(CpuInfo::AVX512);
+      default:
+        return false;
+    }
+  }
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/double_conversion.h

@@ -0,0 +1,32 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include "arrow/vendored/double-conversion/double-conversion.h"  // IWYU pragma: export
+
+namespace arrow {
+namespace util {
+namespace double_conversion {
+
+using ::arrow_vendored::double_conversion::DoubleToStringConverter;
+using ::arrow_vendored::double_conversion::StringBuilder;
+using ::arrow_vendored::double_conversion::StringToDoubleConverter;
+
+}  // namespace double_conversion
+}  // namespace util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/endian.h

@@ -0,0 +1,245 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#ifdef _WIN32
+#define ARROW_LITTLE_ENDIAN 1
+#else
+#if defined(__APPLE__) || defined(__FreeBSD__)
+#include <machine/endian.h>  // IWYU pragma: keep
+#elif defined(sun) || defined(__sun)
+#include <sys/byteorder.h>  // IWYU pragma: keep
+#else
+#include <endian.h>  // IWYU pragma: keep
+#endif
+#
+#ifndef __BYTE_ORDER__
+#error "__BYTE_ORDER__ not defined"
+#endif
+#
+#ifndef __ORDER_LITTLE_ENDIAN__
+#error "__ORDER_LITTLE_ENDIAN__ not defined"
+#endif
+#
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#define ARROW_LITTLE_ENDIAN 1
+#else
+#define ARROW_LITTLE_ENDIAN 0
+#endif
+#endif
+
+#if defined(_MSC_VER)
+#include <intrin.h>  // IWYU pragma: keep
+#define ARROW_BYTE_SWAP64 _byteswap_uint64
+#define ARROW_BYTE_SWAP32 _byteswap_ulong
+#else
+#define ARROW_BYTE_SWAP64 __builtin_bswap64
+#define ARROW_BYTE_SWAP32 __builtin_bswap32
+#endif
+
+#include <algorithm>
+#include <array>
+
+#include "arrow/util/type_traits.h"
+#include "arrow/util/ubsan.h"
+
+namespace arrow {
+namespace bit_util {
+
+//
+// Byte-swap 16-bit, 32-bit and 64-bit values
+//
+
+// Swap the byte order (i.e. endianness)
+static inline int64_t ByteSwap(int64_t value) { return ARROW_BYTE_SWAP64(value); }
+static inline uint64_t ByteSwap(uint64_t value) {
+  return static_cast<uint64_t>(ARROW_BYTE_SWAP64(value));
+}
+static inline int32_t ByteSwap(int32_t value) { return ARROW_BYTE_SWAP32(value); }
+static inline uint32_t ByteSwap(uint32_t value) {
+  return static_cast<uint32_t>(ARROW_BYTE_SWAP32(value));
+}
+static inline int16_t ByteSwap(int16_t value) {
+  constexpr auto m = static_cast<int16_t>(0xff);
+  return static_cast<int16_t>(((value >> 8) & m) | ((value & m) << 8));
+}
+static inline uint16_t ByteSwap(uint16_t value) {
+  return static_cast<uint16_t>(ByteSwap(static_cast<int16_t>(value)));
+}
+static inline uint8_t ByteSwap(uint8_t value) { return value; }
+static inline int8_t ByteSwap(int8_t value) { return value; }
+static inline double ByteSwap(double value) {
+  const uint64_t swapped = ARROW_BYTE_SWAP64(util::SafeCopy<uint64_t>(value));
+  return util::SafeCopy<double>(swapped);
+}
+static inline float ByteSwap(float value) {
+  const uint32_t swapped = ARROW_BYTE_SWAP32(util::SafeCopy<uint32_t>(value));
+  return util::SafeCopy<float>(swapped);
+}
+
+// Write the swapped bytes into dst. Src and dst cannot overlap.
+static inline void ByteSwap(void* dst, const void* src, int len) {
+  switch (len) {
+    case 1:
+      *reinterpret_cast<int8_t*>(dst) = *reinterpret_cast<const int8_t*>(src);
+      return;
+    case 2:
+      *reinterpret_cast<int16_t*>(dst) = ByteSwap(*reinterpret_cast<const int16_t*>(src));
+      return;
+    case 4:
+      *reinterpret_cast<int32_t*>(dst) = ByteSwap(*reinterpret_cast<const int32_t*>(src));
+      return;
+    case 8:
+      *reinterpret_cast<int64_t*>(dst) = ByteSwap(*reinterpret_cast<const int64_t*>(src));
+      return;
+    default:
+      break;
+  }
+
+  auto d = reinterpret_cast<uint8_t*>(dst);
+  auto s = reinterpret_cast<const uint8_t*>(src);
+  for (int i = 0; i < len; ++i) {
+    d[i] = s[len - i - 1];
+  }
+}
+
+// Convert to little/big endian format from the machine's native endian format.
+#if ARROW_LITTLE_ENDIAN
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T ToBigEndian(T value) {
+  return ByteSwap(value);
+}
+
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T ToLittleEndian(T value) {
+  return value;
+}
+#else
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T ToBigEndian(T value) {
+  return value;
+}
+
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T ToLittleEndian(T value) {
+  return ByteSwap(value);
+}
+#endif
+
+// Convert from big/little endian format to the machine's native endian format.
+#if ARROW_LITTLE_ENDIAN
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T FromBigEndian(T value) {
+  return ByteSwap(value);
+}
+
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T FromLittleEndian(T value) {
+  return value;
+}
+#else
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T FromBigEndian(T value) {
+  return value;
+}
+
+template <typename T, typename = internal::EnableIfIsOneOf<
+                          T, int64_t, uint64_t, int32_t, uint32_t, int16_t, uint16_t,
+                          uint8_t, int8_t, float, double, bool>>
+static inline T FromLittleEndian(T value) {
+  return ByteSwap(value);
+}
+#endif
+
+// Handle endianness in *word* granularity (keep individual array element untouched)
+namespace little_endian {
+
+namespace detail {
+
+// Read a native endian array as little endian
+template <typename T, size_t N>
+struct Reader {
+  const std::array<T, N>& native_array;
+
+  explicit Reader(const std::array<T, N>& native_array) : native_array(native_array) {}
+
+  const T& operator[](size_t i) const {
+    return native_array[ARROW_LITTLE_ENDIAN ? i : N - 1 - i];
+  }
+};
+
+// Read/write a native endian array as little endian
+template <typename T, size_t N>
+struct Writer {
+  std::array<T, N>* native_array;
+
+  explicit Writer(std::array<T, N>* native_array) : native_array(native_array) {}
+
+  const T& operator[](size_t i) const {
+    return (*native_array)[ARROW_LITTLE_ENDIAN ? i : N - 1 - i];
+  }
+  T& operator[](size_t i) { return (*native_array)[ARROW_LITTLE_ENDIAN ? i : N - 1 - i]; }
+};
+
+}  // namespace detail
+
+// Construct array reader and try to deduce template augments
+template <typename T, size_t N>
+static inline detail::Reader<T, N> Make(const std::array<T, N>& native_array) {
+  return detail::Reader<T, N>(native_array);
+}
+
+// Construct array writer and try to deduce template augments
+template <typename T, size_t N>
+static inline detail::Writer<T, N> Make(std::array<T, N>* native_array) {
+  return detail::Writer<T, N>(native_array);
+}
+
+// Convert little endian array to native endian
+template <typename T, size_t N>
+static inline std::array<T, N> ToNative(std::array<T, N> array) {
+  if (!ARROW_LITTLE_ENDIAN) {
+    std::reverse(array.begin(), array.end());
+  }
+  return array;
+}
+
+// Convert native endian array to little endian
+template <typename T, size_t N>
+static inline std::array<T, N> FromNative(std::array<T, N> array) {
+  return ToNative(array);
+}
+
+}  // namespace little_endian
+
+}  // namespace bit_util
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/formatting.h

@@ -0,0 +1,656 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// This is a private header for number-to-string formatting utilities
+
+#pragma once
+
+#include <array>
+#include <cassert>
+#include <chrono>
+#include <limits>
+#include <memory>
+#include <string>
+#include <string_view>
+#include <type_traits>
+#include <utility>
+
+#include "arrow/status.h"
+#include "arrow/type.h"
+#include "arrow/type_traits.h"
+#include "arrow/util/double_conversion.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/string.h"
+#include "arrow/util/time.h"
+#include "arrow/util/visibility.h"
+#include "arrow/vendored/datetime.h"
+
+namespace arrow {
+namespace internal {
+
+/// \brief The entry point for conversion to strings.
+template <typename ARROW_TYPE, typename Enable = void>
+class StringFormatter;
+
+template <typename T>
+struct is_formattable {
+  template <typename U, typename = typename StringFormatter<U>::value_type>
+  static std::true_type Test(U*);
+
+  template <typename U>
+  static std::false_type Test(...);
+
+  static constexpr bool value = decltype(Test<T>(NULLPTR))::value;
+};
+
+template <typename T, typename R = void>
+using enable_if_formattable = enable_if_t<is_formattable<T>::value, R>;
+
+template <typename Appender>
+using Return = decltype(std::declval<Appender>()(std::string_view{}));
+
+/////////////////////////////////////////////////////////////////////////
+// Boolean formatting
+
+template <>
+class StringFormatter<BooleanType> {
+ public:
+  explicit StringFormatter(const DataType* = NULLPTR) {}
+
+  using value_type = bool;
+
+  template <typename Appender>
+  Return<Appender> operator()(bool value, Appender&& append) {
+    if (value) {
+      const char string[] = "true";
+      return append(std::string_view(string));
+    } else {
+      const char string[] = "false";
+      return append(std::string_view(string));
+    }
+  }
+};
+
+/////////////////////////////////////////////////////////////////////////
+// Decimals formatting
+
+template <typename ARROW_TYPE>
+class DecimalToStringFormatterMixin {
+ public:
+  explicit DecimalToStringFormatterMixin(const DataType* type)
+      : scale_(static_cast<const ARROW_TYPE*>(type)->scale()) {}
+
+  using value_type = typename TypeTraits<ARROW_TYPE>::CType;
+
+  template <typename Appender>
+  Return<Appender> operator()(const value_type& value, Appender&& append) {
+    return append(value.ToString(scale_));
+  }
+
+ private:
+  int32_t scale_;
+};
+
+template <>
+class StringFormatter<Decimal128Type>
+    : public DecimalToStringFormatterMixin<Decimal128Type> {
+  using DecimalToStringFormatterMixin::DecimalToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<Decimal256Type>
+    : public DecimalToStringFormatterMixin<Decimal256Type> {
+  using DecimalToStringFormatterMixin::DecimalToStringFormatterMixin;
+};
+
+/////////////////////////////////////////////////////////////////////////
+// Integer formatting
+
+namespace detail {
+
+// A 2x100 direct table mapping integers in [0..99] to their decimal representations.
+ARROW_EXPORT extern const char digit_pairs[];
+
+// Based on fmtlib's format_int class:
+// Write digits from right to left into a stack allocated buffer.
+// \pre *cursor points to the byte after the one that will be written.
+// \post *cursor points to the byte that was written.
+inline void FormatOneChar(char c, char** cursor) { *(--(*cursor)) = c; }
+
+template <typename Int>
+void FormatOneDigit(Int value, char** cursor) {
+  assert(value >= 0 && value <= 9);
+  FormatOneChar(static_cast<char>('0' + value), cursor);
+}
+
+// GH-35662: I don't know why but the following combination causes SEGV:
+// * template implementation without inline
+// * MinGW
+// * Release build
+template <typename Int>
+inline void FormatTwoDigits(Int value, char** cursor) {
+  assert(value >= 0 && value <= 99);
+  auto digit_pair = &digit_pairs[value * 2];
+  FormatOneChar(digit_pair[1], cursor);
+  FormatOneChar(digit_pair[0], cursor);
+}
+
+template <typename Int>
+void FormatAllDigits(Int value, char** cursor) {
+  assert(value >= 0);
+  while (value >= 100) {
+    FormatTwoDigits(value % 100, cursor);
+    value /= 100;
+  }
+
+  if (value >= 10) {
+    FormatTwoDigits(value, cursor);
+  } else {
+    FormatOneDigit(value, cursor);
+  }
+}
+
+template <typename Int>
+void FormatAllDigitsLeftPadded(Int value, size_t pad, char pad_char, char** cursor) {
+  auto end = *cursor - pad;
+  FormatAllDigits(value, cursor);
+  while (*cursor > end) {
+    FormatOneChar(pad_char, cursor);
+  }
+}
+
+template <size_t BUFFER_SIZE>
+std::string_view ViewDigitBuffer(const std::array<char, BUFFER_SIZE>& buffer,
+                                 char* cursor) {
+  auto buffer_end = buffer.data() + BUFFER_SIZE;
+  return {cursor, static_cast<size_t>(buffer_end - cursor)};
+}
+
+template <typename Int, typename UInt = typename std::make_unsigned<Int>::type>
+constexpr UInt Abs(Int value) {
+  return value < 0 ? ~static_cast<UInt>(value) + 1 : static_cast<UInt>(value);
+}
+
+template <typename Int>
+constexpr size_t Digits10(Int value) {
+  return value <= 9 ? 1 : Digits10(value / 10) + 1;
+}
+
+}  // namespace detail
+
+template <typename ARROW_TYPE>
+class IntToStringFormatterMixin {
+ public:
+  explicit IntToStringFormatterMixin(const DataType* = NULLPTR) {}
+
+  using value_type = typename ARROW_TYPE::c_type;
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    constexpr size_t buffer_size =
+        detail::Digits10(std::numeric_limits<value_type>::max()) + 1;
+
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+    detail::FormatAllDigits(detail::Abs(value), &cursor);
+    if (value < 0) {
+      detail::FormatOneChar('-', &cursor);
+    }
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+};
+
+template <>
+class StringFormatter<Int8Type> : public IntToStringFormatterMixin<Int8Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<Int16Type> : public IntToStringFormatterMixin<Int16Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<Int32Type> : public IntToStringFormatterMixin<Int32Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<Int64Type> : public IntToStringFormatterMixin<Int64Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<UInt8Type> : public IntToStringFormatterMixin<UInt8Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<UInt16Type> : public IntToStringFormatterMixin<UInt16Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<UInt32Type> : public IntToStringFormatterMixin<UInt32Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<UInt64Type> : public IntToStringFormatterMixin<UInt64Type> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+/////////////////////////////////////////////////////////////////////////
+// Floating-point formatting
+
+class ARROW_EXPORT FloatToStringFormatter {
+ public:
+  FloatToStringFormatter();
+  FloatToStringFormatter(int flags, const char* inf_symbol, const char* nan_symbol,
+                         char exp_character, int decimal_in_shortest_low,
+                         int decimal_in_shortest_high,
+                         int max_leading_padding_zeroes_in_precision_mode,
+                         int max_trailing_padding_zeroes_in_precision_mode);
+  ~FloatToStringFormatter();
+
+  // Returns the number of characters written
+  int FormatFloat(float v, char* out_buffer, int out_size);
+  int FormatFloat(double v, char* out_buffer, int out_size);
+  int FormatFloat(uint16_t v, char* out_buffer, int out_size);
+
+ protected:
+  struct Impl;
+  std::unique_ptr<Impl> impl_;
+};
+
+template <typename ARROW_TYPE>
+class FloatToStringFormatterMixin : public FloatToStringFormatter {
+ public:
+  using value_type = typename ARROW_TYPE::c_type;
+
+  static constexpr int buffer_size = 50;
+
+  explicit FloatToStringFormatterMixin(const DataType* = NULLPTR) {}
+
+  FloatToStringFormatterMixin(int flags, const char* inf_symbol, const char* nan_symbol,
+                              char exp_character, int decimal_in_shortest_low,
+                              int decimal_in_shortest_high,
+                              int max_leading_padding_zeroes_in_precision_mode,
+                              int max_trailing_padding_zeroes_in_precision_mode)
+      : FloatToStringFormatter(flags, inf_symbol, nan_symbol, exp_character,
+                               decimal_in_shortest_low, decimal_in_shortest_high,
+                               max_leading_padding_zeroes_in_precision_mode,
+                               max_trailing_padding_zeroes_in_precision_mode) {}
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    char buffer[buffer_size];
+    int size = FormatFloat(value, buffer, buffer_size);
+    return append(std::string_view(buffer, size));
+  }
+};
+
+template <>
+class StringFormatter<HalfFloatType> : public FloatToStringFormatterMixin<HalfFloatType> {
+ public:
+  using FloatToStringFormatterMixin::FloatToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<FloatType> : public FloatToStringFormatterMixin<FloatType> {
+ public:
+  using FloatToStringFormatterMixin::FloatToStringFormatterMixin;
+};
+
+template <>
+class StringFormatter<DoubleType> : public FloatToStringFormatterMixin<DoubleType> {
+ public:
+  using FloatToStringFormatterMixin::FloatToStringFormatterMixin;
+};
+
+/////////////////////////////////////////////////////////////////////////
+// Temporal formatting
+
+namespace detail {
+
+constexpr size_t BufferSizeYYYY_MM_DD() {
+  // "-"? "99999-12-31"
+  return 1 + detail::Digits10(99999) + 1 + detail::Digits10(12) + 1 +
+         detail::Digits10(31);
+}
+
+inline void FormatYYYY_MM_DD(arrow_vendored::date::year_month_day ymd, char** cursor) {
+  FormatTwoDigits(static_cast<unsigned>(ymd.day()), cursor);
+  FormatOneChar('-', cursor);
+  FormatTwoDigits(static_cast<unsigned>(ymd.month()), cursor);
+  FormatOneChar('-', cursor);
+  auto year = static_cast<int>(ymd.year());
+  const auto is_neg_year = year < 0;
+  year = std::abs(year);
+  assert(year <= 99999);
+  FormatTwoDigits(year % 100, cursor);
+  year /= 100;
+  FormatTwoDigits(year % 100, cursor);
+  if (year >= 100) {
+    FormatOneDigit(year / 100, cursor);
+  }
+  if (is_neg_year) {
+    FormatOneChar('-', cursor);
+  }
+}
+
+template <typename Duration>
+constexpr size_t BufferSizeHH_MM_SS() {
+  // "23:59:59" ("." "9"+)?
+  return detail::Digits10(23) + 1 + detail::Digits10(59) + 1 + detail::Digits10(59) + 1 +
+         detail::Digits10(Duration::period::den) - 1;
+}
+
+template <typename Duration>
+void FormatHH_MM_SS(arrow_vendored::date::hh_mm_ss<Duration> hms, char** cursor) {
+  constexpr size_t subsecond_digits = Digits10(Duration::period::den) - 1;
+  if (subsecond_digits != 0) {
+    FormatAllDigitsLeftPadded(hms.subseconds().count(), subsecond_digits, '0', cursor);
+    FormatOneChar('.', cursor);
+  }
+  FormatTwoDigits(hms.seconds().count(), cursor);
+  FormatOneChar(':', cursor);
+  FormatTwoDigits(hms.minutes().count(), cursor);
+  FormatOneChar(':', cursor);
+  FormatTwoDigits(hms.hours().count(), cursor);
+}
+
+// Some out-of-bound datetime values would result in erroneous printing
+// because of silent integer wraparound in the `arrow_vendored::date` library.
+//
+// To avoid such misprinting, we must therefore check the bounds explicitly.
+// The bounds correspond to start of year -32767 and end of year 32767,
+// respectively (-32768 is an invalid year value in `arrow_vendored::date`).
+//
+// Note these values are the same as documented for C++20:
+// https://en.cppreference.com/w/cpp/chrono/year_month_day/operator_days
+template <typename Unit>
+bool IsDateTimeInRange(Unit duration) {
+  constexpr Unit kMinIncl =
+      std::chrono::duration_cast<Unit>(arrow_vendored::date::days{-12687428});
+  constexpr Unit kMaxExcl =
+      std::chrono::duration_cast<Unit>(arrow_vendored::date::days{11248738});
+  return duration >= kMinIncl && duration < kMaxExcl;
+}
+
+// IsDateTimeInRange() specialization for nanoseconds: a 64-bit number of
+// nanoseconds cannot represent years outside of the [-32767, 32767]
+// range, and the {kMinIncl, kMaxExcl} constants above would overflow.
+constexpr bool IsDateTimeInRange(std::chrono::nanoseconds duration) { return true; }
+
+template <typename Unit>
+bool IsTimeInRange(Unit duration) {
+  constexpr Unit kMinIncl = std::chrono::duration_cast<Unit>(std::chrono::seconds{0});
+  constexpr Unit kMaxExcl = std::chrono::duration_cast<Unit>(std::chrono::seconds{86400});
+  return duration >= kMinIncl && duration < kMaxExcl;
+}
+
+template <typename RawValue, typename Appender>
+Return<Appender> FormatOutOfRange(RawValue&& raw_value, Appender&& append) {
+  // XXX locale-sensitive but good enough for now
+  std::string formatted = "<value out of range: " + ToChars(raw_value) + ">";
+  return append(std::move(formatted));
+}
+
+const auto kEpoch = arrow_vendored::date::sys_days{arrow_vendored::date::jan / 1 / 1970};
+
+}  // namespace detail
+
+template <>
+class StringFormatter<DurationType> : public IntToStringFormatterMixin<DurationType> {
+  using IntToStringFormatterMixin::IntToStringFormatterMixin;
+};
+
+class DateToStringFormatterMixin {
+ public:
+  explicit DateToStringFormatterMixin(const DataType* = NULLPTR) {}
+
+ protected:
+  template <typename Appender>
+  Return<Appender> FormatDays(arrow_vendored::date::days since_epoch, Appender&& append) {
+    arrow_vendored::date::sys_days timepoint_days{since_epoch};
+
+    constexpr size_t buffer_size = detail::BufferSizeYYYY_MM_DD();
+
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    detail::FormatYYYY_MM_DD(arrow_vendored::date::year_month_day{timepoint_days},
+                             &cursor);
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+};
+
+template <>
+class StringFormatter<Date32Type> : public DateToStringFormatterMixin {
+ public:
+  using value_type = typename Date32Type::c_type;
+
+  using DateToStringFormatterMixin::DateToStringFormatterMixin;
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    const auto since_epoch = arrow_vendored::date::days{value};
+    if (!ARROW_PREDICT_TRUE(detail::IsDateTimeInRange(since_epoch))) {
+      return detail::FormatOutOfRange(value, append);
+    }
+    return FormatDays(since_epoch, std::forward<Appender>(append));
+  }
+};
+
+template <>
+class StringFormatter<Date64Type> : public DateToStringFormatterMixin {
+ public:
+  using value_type = typename Date64Type::c_type;
+
+  using DateToStringFormatterMixin::DateToStringFormatterMixin;
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    const auto since_epoch = std::chrono::milliseconds{value};
+    if (!ARROW_PREDICT_TRUE(detail::IsDateTimeInRange(since_epoch))) {
+      return detail::FormatOutOfRange(value, append);
+    }
+    return FormatDays(std::chrono::duration_cast<arrow_vendored::date::days>(since_epoch),
+                      std::forward<Appender>(append));
+  }
+};
+
+template <>
+class StringFormatter<TimestampType> {
+ public:
+  using value_type = int64_t;
+
+  explicit StringFormatter(const DataType* type)
+      : unit_(checked_cast<const TimestampType&>(*type).unit()),
+        timezone_(checked_cast<const TimestampType&>(*type).timezone()) {}
+
+  template <typename Duration, typename Appender>
+  Return<Appender> operator()(Duration, value_type value, Appender&& append) {
+    using arrow_vendored::date::days;
+
+    const Duration since_epoch{value};
+    if (!ARROW_PREDICT_TRUE(detail::IsDateTimeInRange(since_epoch))) {
+      return detail::FormatOutOfRange(value, append);
+    }
+
+    const auto timepoint = detail::kEpoch + since_epoch;
+    // Round days towards zero
+    // (the naive approach of using arrow_vendored::date::floor() would
+    //  result in UB for very large negative timestamps, similarly as
+    //  https://github.com/HowardHinnant/date/issues/696)
+    auto timepoint_days = std::chrono::time_point_cast<days>(timepoint);
+    Duration since_midnight;
+    if (timepoint_days <= timepoint) {
+      // Year >= 1970
+      since_midnight = timepoint - timepoint_days;
+    } else {
+      // Year < 1970
+      since_midnight = days(1) - (timepoint_days - timepoint);
+      timepoint_days -= days(1);
+    }
+
+    // YYYY_MM_DD " " HH_MM_SS "Z"?
+    constexpr size_t buffer_size =
+        detail::BufferSizeYYYY_MM_DD() + 1 + detail::BufferSizeHH_MM_SS<Duration>() + 1;
+
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    if (timezone_.size() > 0) {
+      detail::FormatOneChar('Z', &cursor);
+    }
+    detail::FormatHH_MM_SS(arrow_vendored::date::make_time(since_midnight), &cursor);
+    detail::FormatOneChar(' ', &cursor);
+    detail::FormatYYYY_MM_DD(timepoint_days, &cursor);
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    return util::VisitDuration(unit_, *this, value, std::forward<Appender>(append));
+  }
+
+ private:
+  TimeUnit::type unit_;
+  std::string timezone_;
+};
+
+template <typename T>
+class StringFormatter<T, enable_if_time<T>> {
+ public:
+  using value_type = typename T::c_type;
+
+  explicit StringFormatter(const DataType* type)
+      : unit_(checked_cast<const T&>(*type).unit()) {}
+
+  template <typename Duration, typename Appender>
+  Return<Appender> operator()(Duration, value_type count, Appender&& append) {
+    const Duration since_midnight{count};
+    if (!ARROW_PREDICT_TRUE(detail::IsTimeInRange(since_midnight))) {
+      return detail::FormatOutOfRange(count, append);
+    }
+
+    constexpr size_t buffer_size = detail::BufferSizeHH_MM_SS<Duration>();
+
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    detail::FormatHH_MM_SS(arrow_vendored::date::make_time(since_midnight), &cursor);
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type value, Appender&& append) {
+    return util::VisitDuration(unit_, *this, value, std::forward<Appender>(append));
+  }
+
+ private:
+  TimeUnit::type unit_;
+};
+
+template <>
+class StringFormatter<MonthIntervalType> {
+ public:
+  using value_type = MonthIntervalType::c_type;
+
+  explicit StringFormatter(const DataType*) {}
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type interval, Appender&& append) {
+    constexpr size_t buffer_size =
+        /*'m'*/ 3 + /*negative signs*/ 1 +
+        /*months*/ detail::Digits10(std::numeric_limits<value_type>::max());
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    detail::FormatOneChar('M', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval), &cursor);
+    if (interval < 0) detail::FormatOneChar('-', &cursor);
+
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+};
+
+template <>
+class StringFormatter<DayTimeIntervalType> {
+ public:
+  using value_type = DayTimeIntervalType::DayMilliseconds;
+
+  explicit StringFormatter(const DataType*) {}
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type interval, Appender&& append) {
+    constexpr size_t buffer_size =
+        /*d, ms*/ 3 + /*negative signs*/ 2 +
+        /*days/milliseconds*/ 2 * detail::Digits10(std::numeric_limits<int32_t>::max());
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    detail::FormatOneChar('s', &cursor);
+    detail::FormatOneChar('m', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval.milliseconds), &cursor);
+    if (interval.milliseconds < 0) detail::FormatOneChar('-', &cursor);
+
+    detail::FormatOneChar('d', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval.days), &cursor);
+    if (interval.days < 0) detail::FormatOneChar('-', &cursor);
+
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+};
+
+template <>
+class StringFormatter<MonthDayNanoIntervalType> {
+ public:
+  using value_type = MonthDayNanoIntervalType::MonthDayNanos;
+
+  explicit StringFormatter(const DataType*) {}
+
+  template <typename Appender>
+  Return<Appender> operator()(value_type interval, Appender&& append) {
+    constexpr size_t buffer_size =
+        /*m, d, ns*/ 4 + /*negative signs*/ 3 +
+        /*months/days*/ 2 * detail::Digits10(std::numeric_limits<int32_t>::max()) +
+        /*nanoseconds*/ detail::Digits10(std::numeric_limits<int64_t>::max());
+    std::array<char, buffer_size> buffer;
+    char* cursor = buffer.data() + buffer_size;
+
+    detail::FormatOneChar('s', &cursor);
+    detail::FormatOneChar('n', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval.nanoseconds), &cursor);
+    if (interval.nanoseconds < 0) detail::FormatOneChar('-', &cursor);
+
+    detail::FormatOneChar('d', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval.days), &cursor);
+    if (interval.days < 0) detail::FormatOneChar('-', &cursor);
+
+    detail::FormatOneChar('M', &cursor);
+    detail::FormatAllDigits(detail::Abs(interval.months), &cursor);
+    if (interval.months < 0) detail::FormatOneChar('-', &cursor);
+
+    return append(detail::ViewDigitBuffer(buffer, cursor));
+  }
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/functional.h

@@ -0,0 +1,160 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <memory>
+#include <tuple>
+#include <type_traits>
+
+#include "arrow/result.h"
+#include "arrow/util/macros.h"
+
+namespace arrow {
+namespace internal {
+
+struct Empty {
+  static Result<Empty> ToResult(Status s) {
+    if (ARROW_PREDICT_TRUE(s.ok())) {
+      return Empty{};
+    }
+    return s;
+  }
+};
+
+/// Helper struct for examining lambdas and other callables.
+/// TODO(ARROW-12655) support function pointers
+struct call_traits {
+ public:
+  template <typename R, typename... A>
+  static std::false_type is_overloaded_impl(R(A...));
+
+  template <typename F>
+  static std::false_type is_overloaded_impl(decltype(&F::operator())*);
+
+  template <typename F>
+  static std::true_type is_overloaded_impl(...);
+
+  template <typename F, typename R, typename... A>
+  static R return_type_impl(R (F::*)(A...));
+
+  template <typename F, typename R, typename... A>
+  static R return_type_impl(R (F::*)(A...) const);
+
+  template <std::size_t I, typename F, typename R, typename... A>
+  static typename std::tuple_element<I, std::tuple<A...>>::type argument_type_impl(
+      R (F::*)(A...));
+
+  template <std::size_t I, typename F, typename R, typename... A>
+  static typename std::tuple_element<I, std::tuple<A...>>::type argument_type_impl(
+      R (F::*)(A...) const);
+
+  template <std::size_t I, typename F, typename R, typename... A>
+  static typename std::tuple_element<I, std::tuple<A...>>::type argument_type_impl(
+      R (F::*)(A...) &&);
+
+  template <typename F, typename R, typename... A>
+  static std::integral_constant<int, sizeof...(A)> argument_count_impl(R (F::*)(A...));
+
+  template <typename F, typename R, typename... A>
+  static std::integral_constant<int, sizeof...(A)> argument_count_impl(R (F::*)(A...)
+                                                                           const);
+
+  template <typename F, typename R, typename... A>
+  static std::integral_constant<int, sizeof...(A)> argument_count_impl(R (F::*)(A...) &&);
+
+  /// bool constant indicating whether F is a callable with more than one possible
+  /// signature. Will be true_type for objects which define multiple operator() or which
+  /// define a template operator()
+  template <typename F>
+  using is_overloaded =
+      decltype(is_overloaded_impl<typename std::decay<F>::type>(NULLPTR));
+
+  template <typename F, typename T = void>
+  using enable_if_overloaded = typename std::enable_if<is_overloaded<F>::value, T>::type;
+
+  template <typename F, typename T = void>
+  using disable_if_overloaded =
+      typename std::enable_if<!is_overloaded<F>::value, T>::type;
+
+  /// If F is not overloaded, the argument types of its call operator can be
+  /// extracted via call_traits::argument_type<Index, F>
+  template <std::size_t I, typename F>
+  using argument_type = decltype(argument_type_impl<I>(&std::decay<F>::type::operator()));
+
+  template <typename F>
+  using argument_count = decltype(argument_count_impl(&std::decay<F>::type::operator()));
+
+  template <typename F>
+  using return_type = decltype(return_type_impl(&std::decay<F>::type::operator()));
+
+  template <typename F, typename T, typename RT = T>
+  using enable_if_return =
+      typename std::enable_if<std::is_same<return_type<F>, T>::value, RT>;
+
+  template <typename T, typename R = void>
+  using enable_if_empty = typename std::enable_if<std::is_same<T, Empty>::value, R>::type;
+
+  template <typename T, typename R = void>
+  using enable_if_not_empty =
+      typename std::enable_if<!std::is_same<T, Empty>::value, R>::type;
+};
+
+/// A type erased callable object which may only be invoked once.
+/// It can be constructed from any lambda which matches the provided call signature.
+/// Invoking it results in destruction of the lambda, freeing any state/references
+/// immediately. Invoking a default constructed FnOnce or one which has already been
+/// invoked will segfault.
+template <typename Signature>
+class FnOnce;
+
+template <typename R, typename... A>
+class FnOnce<R(A...)> {
+ public:
+  FnOnce() = default;
+
+  template <typename Fn,
+            typename = typename std::enable_if<std::is_convertible<
+                decltype(std::declval<Fn&&>()(std::declval<A>()...)), R>::value>::type>
+  FnOnce(Fn fn) : impl_(new FnImpl<Fn>(std::move(fn))) {  // NOLINT runtime/explicit
+  }
+
+  explicit operator bool() const { return impl_ != NULLPTR; }
+
+  R operator()(A... a) && {
+    auto bye = std::move(impl_);
+    return bye->invoke(std::forward<A&&>(a)...);
+  }
+
+ private:
+  struct Impl {
+    virtual ~Impl() = default;
+    virtual R invoke(A&&... a) = 0;
+  };
+
+  template <typename Fn>
+  struct FnImpl : Impl {
+    explicit FnImpl(Fn fn) : fn_(std::move(fn)) {}
+    R invoke(A&&... a) override { return std::move(fn_)(std::forward<A&&>(a)...); }
+    Fn fn_;
+  };
+
+  std::unique_ptr<Impl> impl_;
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/hashing.h

@@ -0,0 +1,944 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Private header, not to be exported
+
+#pragma once
+
+#include <algorithm>
+#include <cassert>
+#include <cmath>
+#include <cstdint>
+#include <cstring>
+#include <limits>
+#include <memory>
+#include <string>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "arrow/array/builder_binary.h"
+#include "arrow/buffer_builder.h"
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/type_fwd.h"
+#include "arrow/type_traits.h"
+#include "arrow/util/bit_util.h"
+#include "arrow/util/bitmap_builders.h"
+#include "arrow/util/endian.h"
+#include "arrow/util/logging.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/ubsan.h"
+
+#define XXH_INLINE_ALL
+
+#include "arrow/vendored/xxhash.h"  // IWYU pragma: keep
+
+namespace arrow {
+namespace internal {
+
+// XXX would it help to have a 32-bit hash value on large datasets?
+typedef uint64_t hash_t;
+
+// Notes about the choice of a hash function.
+// - XXH3 is extremely fast on most data sizes, from small to huge;
+//   faster even than HW CRC-based hashing schemes
+// - our custom hash function for tiny values (< 16 bytes) is still
+//   significantly faster (~30%), at least on this machine and compiler
+
+template <uint64_t AlgNum>
+inline hash_t ComputeStringHash(const void* data, int64_t length);
+
+/// \brief A hash function for bitmaps that can handle offsets and lengths in
+/// terms of number of bits. The hash only depends on the bits actually hashed.
+///
+/// It's the caller's responsibility to ensure that bits_offset + num_bits are
+/// readable from the bitmap.
+///
+/// \pre bits_offset >= 0
+/// \pre num_bits >= 0
+/// \pre (bits_offset + num_bits + 7) / 8 <= readable length in bytes from bitmap
+///
+/// \param bitmap The pointer to the bitmap.
+/// \param seed The seed for the hash function (useful when chaining hash functions).
+/// \param bits_offset The offset in bits relative to the start of the bitmap.
+/// \param num_bits The number of bits after the offset to be hashed.
+ARROW_EXPORT hash_t ComputeBitmapHash(const uint8_t* bitmap, hash_t seed,
+                                      int64_t bits_offset, int64_t num_bits);
+
+template <typename Scalar, uint64_t AlgNum>
+struct ScalarHelperBase {
+  static bool CompareScalars(Scalar u, Scalar v) { return u == v; }
+
+  static hash_t ComputeHash(const Scalar& value) {
+    // Generic hash computation for scalars.  Simply apply the string hash
+    // to the bit representation of the value.
+
+    // XXX in the case of FP values, we'd like equal values to have the same hash,
+    // even if they have different bit representations...
+    return ComputeStringHash<AlgNum>(&value, sizeof(value));
+  }
+};
+
+template <typename Scalar, uint64_t AlgNum = 0, typename Enable = void>
+struct ScalarHelper : public ScalarHelperBase<Scalar, AlgNum> {};
+
+template <typename Scalar, uint64_t AlgNum>
+struct ScalarHelper<Scalar, AlgNum, enable_if_t<std::is_integral<Scalar>::value>>
+    : public ScalarHelperBase<Scalar, AlgNum> {
+  // ScalarHelper specialization for integers
+
+  static hash_t ComputeHash(const Scalar& value) {
+    // Faster hash computation for integers.
+
+    // Two of xxhash's prime multipliers (which are chosen for their
+    // bit dispersion properties)
+    static constexpr uint64_t multipliers[] = {11400714785074694791ULL,
+                                               14029467366897019727ULL};
+
+    // Multiplying by the prime number mixes the low bits into the high bits,
+    // then byte-swapping (which is a single CPU instruction) allows the
+    // combined high and low bits to participate in the initial hash table index.
+    auto h = static_cast<hash_t>(value);
+    return bit_util::ByteSwap(multipliers[AlgNum] * h);
+  }
+};
+
+template <typename Scalar, uint64_t AlgNum>
+struct ScalarHelper<Scalar, AlgNum,
+                    enable_if_t<std::is_same<std::string_view, Scalar>::value>>
+    : public ScalarHelperBase<Scalar, AlgNum> {
+  // ScalarHelper specialization for std::string_view
+
+  static hash_t ComputeHash(std::string_view value) {
+    return ComputeStringHash<AlgNum>(value.data(), static_cast<int64_t>(value.size()));
+  }
+};
+
+template <typename Scalar, uint64_t AlgNum>
+struct ScalarHelper<Scalar, AlgNum, enable_if_t<std::is_floating_point<Scalar>::value>>
+    : public ScalarHelperBase<Scalar, AlgNum> {
+  // ScalarHelper specialization for reals
+
+  static bool CompareScalars(Scalar u, Scalar v) {
+    if (std::isnan(u)) {
+      // XXX should we do a bit-precise comparison?
+      return std::isnan(v);
+    }
+    return u == v;
+  }
+};
+
+template <uint64_t AlgNum = 0>
+hash_t ComputeStringHash(const void* data, int64_t length) {
+  if (ARROW_PREDICT_TRUE(length <= 16)) {
+    // Specialize for small hash strings, as they are quite common as
+    // hash table keys.  Even XXH3 isn't quite as fast.
+    auto p = reinterpret_cast<const uint8_t*>(data);
+    auto n = static_cast<uint32_t>(length);
+    if (n <= 8) {
+      if (n <= 3) {
+        if (n == 0) {
+          return 1U;
+        }
+        uint32_t x = (n << 24) ^ (p[0] << 16) ^ (p[n / 2] << 8) ^ p[n - 1];
+        return ScalarHelper<uint32_t, AlgNum>::ComputeHash(x);
+      }
+      // 4 <= length <= 8
+      // We can read the string as two overlapping 32-bit ints, apply
+      // different hash functions to each of them in parallel, then XOR
+      // the results
+      uint32_t x, y;
+      hash_t hx, hy;
+      x = util::SafeLoadAs<uint32_t>(p + n - 4);
+      y = util::SafeLoadAs<uint32_t>(p);
+      hx = ScalarHelper<uint32_t, AlgNum>::ComputeHash(x);
+      hy = ScalarHelper<uint32_t, AlgNum ^ 1>::ComputeHash(y);
+      return n ^ hx ^ hy;
+    }
+    // 8 <= length <= 16
+    // Apply the same principle as above
+    uint64_t x, y;
+    hash_t hx, hy;
+    x = util::SafeLoadAs<uint64_t>(p + n - 8);
+    y = util::SafeLoadAs<uint64_t>(p);
+    hx = ScalarHelper<uint64_t, AlgNum>::ComputeHash(x);
+    hy = ScalarHelper<uint64_t, AlgNum ^ 1>::ComputeHash(y);
+    return n ^ hx ^ hy;
+  }
+
+#if XXH3_SECRET_SIZE_MIN != 136
+#error XXH3_SECRET_SIZE_MIN changed, please fix kXxh3Secrets
+#endif
+
+  // XXH3_64bits_withSeed generates a secret based on the seed, which is too slow.
+  // Instead, we use hard-coded random secrets.  To maximize cache efficiency,
+  // they reuse the same memory area.
+  static constexpr unsigned char kXxh3Secrets[XXH3_SECRET_SIZE_MIN + 1] = {
+      0xe7, 0x8b, 0x13, 0xf9, 0xfc, 0xb5, 0x8e, 0xef, 0x81, 0x48, 0x2c, 0xbf, 0xf9, 0x9f,
+      0xc1, 0x1e, 0x43, 0x6d, 0xbf, 0xa6, 0x6d, 0xb5, 0x72, 0xbc, 0x97, 0xd8, 0x61, 0x24,
+      0x0f, 0x12, 0xe3, 0x05, 0x21, 0xf7, 0x5c, 0x66, 0x67, 0xa5, 0x65, 0x03, 0x96, 0x26,
+      0x69, 0xd8, 0x29, 0x20, 0xf8, 0xc7, 0xb0, 0x3d, 0xdd, 0x7d, 0x18, 0xa0, 0x60, 0x75,
+      0x92, 0xa4, 0xce, 0xba, 0xc0, 0x77, 0xf4, 0xac, 0xb7, 0x03, 0x53, 0xf0, 0x98, 0xce,
+      0xe6, 0x2b, 0x20, 0xc7, 0x82, 0x91, 0xab, 0xbf, 0x68, 0x5c, 0x62, 0x4d, 0x33, 0xa3,
+      0xe1, 0xb3, 0xff, 0x97, 0x54, 0x4c, 0x44, 0x34, 0xb5, 0xb9, 0x32, 0x4c, 0x75, 0x42,
+      0x89, 0x53, 0x94, 0xd4, 0x9f, 0x2b, 0x76, 0x4d, 0x4e, 0xe6, 0xfa, 0x15, 0x3e, 0xc1,
+      0xdb, 0x71, 0x4b, 0x2c, 0x94, 0xf5, 0xfc, 0x8c, 0x89, 0x4b, 0xfb, 0xc1, 0x82, 0xa5,
+      0x6a, 0x53, 0xf9, 0x4a, 0xba, 0xce, 0x1f, 0xc0, 0x97, 0x1a, 0x87};
+
+  static_assert(AlgNum < 2, "AlgNum too large");
+  static constexpr auto secret = kXxh3Secrets + AlgNum;
+  return XXH3_64bits_withSecret(data, static_cast<size_t>(length), secret,
+                                XXH3_SECRET_SIZE_MIN);
+}
+
+// XXX add a HashEq<ArrowType> struct with both hash and compare functions?
+
+// ----------------------------------------------------------------------
+// An open-addressing insert-only hash table (no deletes)
+
+template <typename Payload>
+class HashTable {
+ public:
+  static constexpr hash_t kSentinel = 0ULL;
+  static constexpr int64_t kLoadFactor = 2UL;
+
+  struct Entry {
+    hash_t h;
+    Payload payload;
+
+    // An entry is valid if the hash is different from the sentinel value
+    operator bool() const { return h != kSentinel; }
+  };
+
+  HashTable(MemoryPool* pool, uint64_t capacity) : entries_builder_(pool) {
+    DCHECK_NE(pool, nullptr);
+    // Minimum of 32 elements
+    capacity = std::max<uint64_t>(capacity, 32UL);
+    capacity_ = bit_util::NextPower2(capacity);
+    capacity_mask_ = capacity_ - 1;
+    size_ = 0;
+
+    DCHECK_OK(UpsizeBuffer(capacity_));
+  }
+
+  // Lookup with non-linear probing
+  // cmp_func should have signature bool(const Payload*).
+  // Return a (Entry*, found) pair.
+  template <typename CmpFunc>
+  std::pair<Entry*, bool> Lookup(hash_t h, CmpFunc&& cmp_func) {
+    auto p = Lookup<DoCompare, CmpFunc>(h, entries_, capacity_mask_,
+                                        std::forward<CmpFunc>(cmp_func));
+    return {&entries_[p.first], p.second};
+  }
+
+  template <typename CmpFunc>
+  std::pair<const Entry*, bool> Lookup(hash_t h, CmpFunc&& cmp_func) const {
+    auto p = Lookup<DoCompare, CmpFunc>(h, entries_, capacity_mask_,
+                                        std::forward<CmpFunc>(cmp_func));
+    return {&entries_[p.first], p.second};
+  }
+
+  Status Insert(Entry* entry, hash_t h, const Payload& payload) {
+    // Ensure entry is empty before inserting
+    assert(!*entry);
+    entry->h = FixHash(h);
+    entry->payload = payload;
+    ++size_;
+
+    if (ARROW_PREDICT_FALSE(NeedUpsizing())) {
+      // Resize less frequently since it is expensive
+      return Upsize(capacity_ * kLoadFactor * 2);
+    }
+    return Status::OK();
+  }
+
+  uint64_t size() const { return size_; }
+
+  // Visit all non-empty entries in the table
+  // The visit_func should have signature void(const Entry*)
+  template <typename VisitFunc>
+  void VisitEntries(VisitFunc&& visit_func) const {
+    for (uint64_t i = 0; i < capacity_; i++) {
+      const auto& entry = entries_[i];
+      if (entry) {
+        visit_func(&entry);
+      }
+    }
+  }
+
+ protected:
+  // NoCompare is for when the value is known not to exist in the table
+  enum CompareKind { DoCompare, NoCompare };
+
+  // The workhorse lookup function
+  template <CompareKind CKind, typename CmpFunc>
+  std::pair<uint64_t, bool> Lookup(hash_t h, const Entry* entries, uint64_t size_mask,
+                                   CmpFunc&& cmp_func) const {
+    static constexpr uint8_t perturb_shift = 5;
+
+    uint64_t index, perturb;
+    const Entry* entry;
+
+    h = FixHash(h);
+    index = h & size_mask;
+    perturb = (h >> perturb_shift) + 1U;
+
+    while (true) {
+      entry = &entries[index];
+      if (CompareEntry<CKind, CmpFunc>(h, entry, std::forward<CmpFunc>(cmp_func))) {
+        // Found
+        return {index, true};
+      }
+      if (entry->h == kSentinel) {
+        // Empty slot
+        return {index, false};
+      }
+
+      // Perturbation logic inspired from CPython's set / dict object.
+      // The goal is that all 64 bits of the unmasked hash value eventually
+      // participate in the probing sequence, to minimize clustering.
+      index = (index + perturb) & size_mask;
+      perturb = (perturb >> perturb_shift) + 1U;
+    }
+  }
+
+  template <CompareKind CKind, typename CmpFunc>
+  bool CompareEntry(hash_t h, const Entry* entry, CmpFunc&& cmp_func) const {
+    if (CKind == NoCompare) {
+      return false;
+    } else {
+      return entry->h == h && cmp_func(&entry->payload);
+    }
+  }
+
+  bool NeedUpsizing() const {
+    // Keep the load factor <= 1/2
+    return size_ * kLoadFactor >= capacity_;
+  }
+
+  Status UpsizeBuffer(uint64_t capacity) {
+    RETURN_NOT_OK(entries_builder_.Resize(capacity));
+    entries_ = entries_builder_.mutable_data();
+    memset(static_cast<void*>(entries_), 0, capacity * sizeof(Entry));
+
+    return Status::OK();
+  }
+
+  Status Upsize(uint64_t new_capacity) {
+    assert(new_capacity > capacity_);
+    uint64_t new_mask = new_capacity - 1;
+    assert((new_capacity & new_mask) == 0);  // it's a power of two
+
+    // Stash old entries and seal builder, effectively resetting the Buffer
+    const Entry* old_entries = entries_;
+    ARROW_ASSIGN_OR_RAISE(auto previous, entries_builder_.FinishWithLength(capacity_));
+    // Allocate new buffer
+    RETURN_NOT_OK(UpsizeBuffer(new_capacity));
+
+    for (uint64_t i = 0; i < capacity_; i++) {
+      const auto& entry = old_entries[i];
+      if (entry) {
+        // Dummy compare function will not be called
+        auto p = Lookup<NoCompare>(entry.h, entries_, new_mask,
+                                   [](const Payload*) { return false; });
+        // Lookup<NoCompare> (and CompareEntry<NoCompare>) ensure that an
+        // empty slots is always returned
+        assert(!p.second);
+        entries_[p.first] = entry;
+      }
+    }
+    capacity_ = new_capacity;
+    capacity_mask_ = new_mask;
+
+    return Status::OK();
+  }
+
+  hash_t FixHash(hash_t h) const { return (h == kSentinel) ? 42U : h; }
+
+  // The number of slots available in the hash table array.
+  uint64_t capacity_;
+  uint64_t capacity_mask_;
+  // The number of used slots in the hash table array.
+  uint64_t size_;
+
+  Entry* entries_;
+  TypedBufferBuilder<Entry> entries_builder_;
+};
+
+// XXX typedef memo_index_t int32_t ?
+
+constexpr int32_t kKeyNotFound = -1;
+
+// ----------------------------------------------------------------------
+// A base class for memoization table.
+
+class MemoTable {
+ public:
+  virtual ~MemoTable() = default;
+
+  virtual int32_t size() const = 0;
+};
+
+// ----------------------------------------------------------------------
+// A memoization table for memory-cheap scalar values.
+
+// The memoization table remembers and allows to look up the insertion
+// index for each key.
+
+template <typename Scalar, template <class> class HashTableTemplateType = HashTable>
+class ScalarMemoTable : public MemoTable {
+ public:
+  explicit ScalarMemoTable(MemoryPool* pool, int64_t entries = 0)
+      : hash_table_(pool, static_cast<uint64_t>(entries)) {}
+
+  int32_t Get(const Scalar& value) const {
+    auto cmp_func = [value](const Payload* payload) -> bool {
+      return ScalarHelper<Scalar, 0>::CompareScalars(payload->value, value);
+    };
+    hash_t h = ComputeHash(value);
+    auto p = hash_table_.Lookup(h, cmp_func);
+    if (p.second) {
+      return p.first->payload.memo_index;
+    } else {
+      return kKeyNotFound;
+    }
+  }
+
+  template <typename Func1, typename Func2>
+  Status GetOrInsert(const Scalar& value, Func1&& on_found, Func2&& on_not_found,
+                     int32_t* out_memo_index) {
+    auto cmp_func = [value](const Payload* payload) -> bool {
+      return ScalarHelper<Scalar, 0>::CompareScalars(value, payload->value);
+    };
+    hash_t h = ComputeHash(value);
+    auto p = hash_table_.Lookup(h, cmp_func);
+    int32_t memo_index;
+    if (p.second) {
+      memo_index = p.first->payload.memo_index;
+      on_found(memo_index);
+    } else {
+      memo_index = size();
+      RETURN_NOT_OK(hash_table_.Insert(p.first, h, {value, memo_index}));
+      on_not_found(memo_index);
+    }
+    *out_memo_index = memo_index;
+    return Status::OK();
+  }
+
+  Status GetOrInsert(const Scalar& value, int32_t* out_memo_index) {
+    return GetOrInsert(
+        value, [](int32_t i) {}, [](int32_t i) {}, out_memo_index);
+  }
+
+  int32_t GetNull() const { return null_index_; }
+
+  template <typename Func1, typename Func2>
+  int32_t GetOrInsertNull(Func1&& on_found, Func2&& on_not_found) {
+    int32_t memo_index = GetNull();
+    if (memo_index != kKeyNotFound) {
+      on_found(memo_index);
+    } else {
+      null_index_ = memo_index = size();
+      on_not_found(memo_index);
+    }
+    return memo_index;
+  }
+
+  int32_t GetOrInsertNull() {
+    return GetOrInsertNull([](int32_t i) {}, [](int32_t i) {});
+  }
+
+  // The number of entries in the memo table +1 if null was added.
+  // (which is also 1 + the largest memo index)
+  int32_t size() const override {
+    return static_cast<int32_t>(hash_table_.size()) + (GetNull() != kKeyNotFound);
+  }
+
+  // Copy values starting from index `start` into `out_data`
+  void CopyValues(int32_t start, Scalar* out_data) const {
+    hash_table_.VisitEntries([=](const HashTableEntry* entry) {
+      int32_t index = entry->payload.memo_index - start;
+      if (index >= 0) {
+        out_data[index] = entry->payload.value;
+      }
+    });
+    // Zero-initialize the null entry
+    if (null_index_ != kKeyNotFound) {
+      int32_t index = null_index_ - start;
+      if (index >= 0) {
+        out_data[index] = Scalar{};
+      }
+    }
+  }
+
+  void CopyValues(Scalar* out_data) const { CopyValues(0, out_data); }
+
+ protected:
+  struct Payload {
+    Scalar value;
+    int32_t memo_index;
+  };
+
+  using HashTableType = HashTableTemplateType<Payload>;
+  using HashTableEntry = typename HashTableType::Entry;
+  HashTableType hash_table_;
+  int32_t null_index_ = kKeyNotFound;
+
+  hash_t ComputeHash(const Scalar& value) const {
+    return ScalarHelper<Scalar, 0>::ComputeHash(value);
+  }
+
+ public:
+  // defined here so that `HashTableType` is visible
+  // Merge entries from `other_table` into `this->hash_table_`.
+  Status MergeTable(const ScalarMemoTable& other_table) {
+    const HashTableType& other_hashtable = other_table.hash_table_;
+
+    other_hashtable.VisitEntries([this](const HashTableEntry* other_entry) {
+      int32_t unused;
+      DCHECK_OK(this->GetOrInsert(other_entry->payload.value, &unused));
+    });
+    // TODO: ARROW-17074 - implement proper error handling
+    return Status::OK();
+  }
+};
+
+// ----------------------------------------------------------------------
+// A memoization table for small scalar values, using direct indexing
+
+template <typename Scalar, typename Enable = void>
+struct SmallScalarTraits {};
+
+template <>
+struct SmallScalarTraits<bool> {
+  static constexpr int32_t cardinality = 2;
+
+  static uint32_t AsIndex(bool value) { return value ? 1 : 0; }
+};
+
+template <typename Scalar>
+struct SmallScalarTraits<Scalar, enable_if_t<std::is_integral<Scalar>::value>> {
+  using Unsigned = typename std::make_unsigned<Scalar>::type;
+
+  static constexpr int32_t cardinality = 1U + std::numeric_limits<Unsigned>::max();
+
+  static uint32_t AsIndex(Scalar value) { return static_cast<Unsigned>(value); }
+};
+
+template <typename Scalar, template <class> class HashTableTemplateType = HashTable>
+class SmallScalarMemoTable : public MemoTable {
+ public:
+  explicit SmallScalarMemoTable(MemoryPool* pool, int64_t entries = 0) {
+    std::fill(value_to_index_, value_to_index_ + cardinality + 1, kKeyNotFound);
+    index_to_value_.reserve(cardinality);
+  }
+
+  int32_t Get(const Scalar value) const {
+    auto value_index = AsIndex(value);
+    return value_to_index_[value_index];
+  }
+
+  template <typename Func1, typename Func2>
+  Status GetOrInsert(const Scalar value, Func1&& on_found, Func2&& on_not_found,
+                     int32_t* out_memo_index) {
+    auto value_index = AsIndex(value);
+    auto memo_index = value_to_index_[value_index];
+    if (memo_index == kKeyNotFound) {
+      memo_index = static_cast<int32_t>(index_to_value_.size());
+      index_to_value_.push_back(value);
+      value_to_index_[value_index] = memo_index;
+      DCHECK_LT(memo_index, cardinality + 1);
+      on_not_found(memo_index);
+    } else {
+      on_found(memo_index);
+    }
+    *out_memo_index = memo_index;
+    return Status::OK();
+  }
+
+  Status GetOrInsert(const Scalar value, int32_t* out_memo_index) {
+    return GetOrInsert(
+        value, [](int32_t i) {}, [](int32_t i) {}, out_memo_index);
+  }
+
+  int32_t GetNull() const { return value_to_index_[cardinality]; }
+
+  template <typename Func1, typename Func2>
+  int32_t GetOrInsertNull(Func1&& on_found, Func2&& on_not_found) {
+    auto memo_index = GetNull();
+    if (memo_index == kKeyNotFound) {
+      memo_index = value_to_index_[cardinality] = size();
+      index_to_value_.push_back(0);
+      on_not_found(memo_index);
+    } else {
+      on_found(memo_index);
+    }
+    return memo_index;
+  }
+
+  int32_t GetOrInsertNull() {
+    return GetOrInsertNull([](int32_t i) {}, [](int32_t i) {});
+  }
+
+  // The number of entries in the memo table
+  // (which is also 1 + the largest memo index)
+  int32_t size() const override { return static_cast<int32_t>(index_to_value_.size()); }
+
+  // Merge entries from `other_table` into `this`.
+  Status MergeTable(const SmallScalarMemoTable& other_table) {
+    for (const Scalar& other_val : other_table.index_to_value_) {
+      int32_t unused;
+      RETURN_NOT_OK(this->GetOrInsert(other_val, &unused));
+    }
+    return Status::OK();
+  }
+
+  // Copy values starting from index `start` into `out_data`
+  void CopyValues(int32_t start, Scalar* out_data) const {
+    DCHECK_GE(start, 0);
+    DCHECK_LE(static_cast<size_t>(start), index_to_value_.size());
+    int64_t offset = start * static_cast<int32_t>(sizeof(Scalar));
+    memcpy(out_data, index_to_value_.data() + offset, (size() - start) * sizeof(Scalar));
+  }
+
+  void CopyValues(Scalar* out_data) const { CopyValues(0, out_data); }
+
+  const std::vector<Scalar>& values() const { return index_to_value_; }
+
+ protected:
+  static constexpr auto cardinality = SmallScalarTraits<Scalar>::cardinality;
+  static_assert(cardinality <= 256, "cardinality too large for direct-addressed table");
+
+  uint32_t AsIndex(Scalar value) const {
+    return SmallScalarTraits<Scalar>::AsIndex(value);
+  }
+
+  // The last index is reserved for the null element.
+  int32_t value_to_index_[cardinality + 1];
+  std::vector<Scalar> index_to_value_;
+};
+
+// ----------------------------------------------------------------------
+// A memoization table for variable-sized binary data.
+
+template <typename BinaryBuilderT>
+class BinaryMemoTable : public MemoTable {
+ public:
+  using builder_offset_type = typename BinaryBuilderT::offset_type;
+  explicit BinaryMemoTable(MemoryPool* pool, int64_t entries = 0,
+                           int64_t values_size = -1)
+      : hash_table_(pool, static_cast<uint64_t>(entries)), binary_builder_(pool) {
+    const int64_t data_size = (values_size < 0) ? entries * 4 : values_size;
+    DCHECK_OK(binary_builder_.Resize(entries));
+    DCHECK_OK(binary_builder_.ReserveData(data_size));
+  }
+
+  int32_t Get(const void* data, builder_offset_type length) const {
+    hash_t h = ComputeStringHash<0>(data, length);
+    auto p = Lookup(h, data, length);
+    if (p.second) {
+      return p.first->payload.memo_index;
+    } else {
+      return kKeyNotFound;
+    }
+  }
+
+  int32_t Get(std::string_view value) const {
+    return Get(value.data(), static_cast<builder_offset_type>(value.length()));
+  }
+
+  template <typename Func1, typename Func2>
+  Status GetOrInsert(const void* data, builder_offset_type length, Func1&& on_found,
+                     Func2&& on_not_found, int32_t* out_memo_index) {
+    hash_t h = ComputeStringHash<0>(data, length);
+    auto p = Lookup(h, data, length);
+    int32_t memo_index;
+    if (p.second) {
+      memo_index = p.first->payload.memo_index;
+      on_found(memo_index);
+    } else {
+      memo_index = size();
+      // Insert string value
+      RETURN_NOT_OK(binary_builder_.Append(static_cast<const char*>(data), length));
+      // Insert hash entry
+      RETURN_NOT_OK(
+          hash_table_.Insert(const_cast<HashTableEntry*>(p.first), h, {memo_index}));
+
+      on_not_found(memo_index);
+    }
+    *out_memo_index = memo_index;
+    return Status::OK();
+  }
+
+  template <typename Func1, typename Func2>
+  Status GetOrInsert(std::string_view value, Func1&& on_found, Func2&& on_not_found,
+                     int32_t* out_memo_index) {
+    return GetOrInsert(value.data(), static_cast<builder_offset_type>(value.length()),
+                       std::forward<Func1>(on_found), std::forward<Func2>(on_not_found),
+                       out_memo_index);
+  }
+
+  Status GetOrInsert(const void* data, builder_offset_type length,
+                     int32_t* out_memo_index) {
+    return GetOrInsert(
+        data, length, [](int32_t i) {}, [](int32_t i) {}, out_memo_index);
+  }
+
+  Status GetOrInsert(std::string_view value, int32_t* out_memo_index) {
+    return GetOrInsert(value.data(), static_cast<builder_offset_type>(value.length()),
+                       out_memo_index);
+  }
+
+  int32_t GetNull() const { return null_index_; }
+
+  template <typename Func1, typename Func2>
+  int32_t GetOrInsertNull(Func1&& on_found, Func2&& on_not_found) {
+    int32_t memo_index = GetNull();
+    if (memo_index == kKeyNotFound) {
+      memo_index = null_index_ = size();
+      DCHECK_OK(binary_builder_.AppendNull());
+      on_not_found(memo_index);
+    } else {
+      on_found(memo_index);
+    }
+    return memo_index;
+  }
+
+  int32_t GetOrInsertNull() {
+    return GetOrInsertNull([](int32_t i) {}, [](int32_t i) {});
+  }
+
+  // The number of entries in the memo table
+  // (which is also 1 + the largest memo index)
+  int32_t size() const override {
+    return static_cast<int32_t>(hash_table_.size() + (GetNull() != kKeyNotFound));
+  }
+
+  int64_t values_size() const { return binary_builder_.value_data_length(); }
+
+  // Copy (n + 1) offsets starting from index `start` into `out_data`
+  template <class Offset>
+  void CopyOffsets(int32_t start, Offset* out_data) const {
+    DCHECK_LE(start, size());
+
+    const builder_offset_type* offsets = binary_builder_.offsets_data();
+    const builder_offset_type delta =
+        start < binary_builder_.length() ? offsets[start] : 0;
+    for (int32_t i = start; i < size(); ++i) {
+      const builder_offset_type adjusted_offset = offsets[i] - delta;
+      Offset cast_offset = static_cast<Offset>(adjusted_offset);
+      assert(static_cast<builder_offset_type>(cast_offset) ==
+             adjusted_offset);  // avoid truncation
+      *out_data++ = cast_offset;
+    }
+
+    // Copy last value since BinaryBuilder only materializes it on in Finish()
+    *out_data = static_cast<Offset>(binary_builder_.value_data_length() - delta);
+  }
+
+  template <class Offset>
+  void CopyOffsets(Offset* out_data) const {
+    CopyOffsets(0, out_data);
+  }
+
+  // Copy values starting from index `start` into `out_data`
+  void CopyValues(int32_t start, uint8_t* out_data) const {
+    CopyValues(start, -1, out_data);
+  }
+
+  // Same as above, but check output size in debug mode
+  void CopyValues(int32_t start, int64_t out_size, uint8_t* out_data) const {
+    DCHECK_LE(start, size());
+
+    // The absolute byte offset of `start` value in the binary buffer.
+    const builder_offset_type offset = binary_builder_.offset(start);
+    const auto length = binary_builder_.value_data_length() - static_cast<size_t>(offset);
+
+    if (out_size != -1) {
+      assert(static_cast<int64_t>(length) <= out_size);
+    }
+
+    auto view = binary_builder_.GetView(start);
+    memcpy(out_data, view.data(), length);
+  }
+
+  void CopyValues(uint8_t* out_data) const { CopyValues(0, -1, out_data); }
+
+  void CopyValues(int64_t out_size, uint8_t* out_data) const {
+    CopyValues(0, out_size, out_data);
+  }
+
+  void CopyFixedWidthValues(int32_t start, int32_t width_size, int64_t out_size,
+                            uint8_t* out_data) const {
+    // This method exists to cope with the fact that the BinaryMemoTable does
+    // not know the fixed width when inserting the null value. The data
+    // buffer hold a zero length string for the null value (if found).
+    //
+    // Thus, the method will properly inject an empty value of the proper width
+    // in the output buffer.
+    //
+    if (start >= size()) {
+      return;
+    }
+
+    int32_t null_index = GetNull();
+    if (null_index < start) {
+      // Nothing to skip, proceed as usual.
+      CopyValues(start, out_size, out_data);
+      return;
+    }
+
+    builder_offset_type left_offset = binary_builder_.offset(start);
+
+    // Ensure that the data length is exactly missing width_size bytes to fit
+    // in the expected output (n_values * width_size).
+#ifndef NDEBUG
+    int64_t data_length = values_size() - static_cast<size_t>(left_offset);
+    assert(data_length + width_size == out_size);
+    ARROW_UNUSED(data_length);
+#endif
+
+    auto in_data = binary_builder_.value_data() + left_offset;
+    // The null use 0-length in the data, slice the data in 2 and skip by
+    // width_size in out_data. [part_1][width_size][part_2]
+    auto null_data_offset = binary_builder_.offset(null_index);
+    auto left_size = null_data_offset - left_offset;
+    if (left_size > 0) {
+      memcpy(out_data, in_data + left_offset, left_size);
+    }
+    // Zero-initialize the null entry
+    memset(out_data + left_size, 0, width_size);
+
+    auto right_size = values_size() - static_cast<size_t>(null_data_offset);
+    if (right_size > 0) {
+      // skip the null fixed size value.
+      auto out_offset = left_size + width_size;
+      assert(out_data + out_offset + right_size == out_data + out_size);
+      memcpy(out_data + out_offset, in_data + null_data_offset, right_size);
+    }
+  }
+
+  // Visit the stored values in insertion order.
+  // The visitor function should have the signature `void(std::string_view)`
+  // or `void(const std::string_view&)`.
+  template <typename VisitFunc>
+  void VisitValues(int32_t start, VisitFunc&& visit) const {
+    for (int32_t i = start; i < size(); ++i) {
+      visit(binary_builder_.GetView(i));
+    }
+  }
+
+ protected:
+  struct Payload {
+    int32_t memo_index;
+  };
+
+  using HashTableType = HashTable<Payload>;
+  using HashTableEntry = typename HashTable<Payload>::Entry;
+  HashTableType hash_table_;
+  BinaryBuilderT binary_builder_;
+
+  int32_t null_index_ = kKeyNotFound;
+
+  std::pair<const HashTableEntry*, bool> Lookup(hash_t h, const void* data,
+                                                builder_offset_type length) const {
+    auto cmp_func = [&](const Payload* payload) {
+      std::string_view lhs = binary_builder_.GetView(payload->memo_index);
+      std::string_view rhs(static_cast<const char*>(data), length);
+      return lhs == rhs;
+    };
+    return hash_table_.Lookup(h, cmp_func);
+  }
+
+ public:
+  Status MergeTable(const BinaryMemoTable& other_table) {
+    other_table.VisitValues(0, [this](std::string_view other_value) {
+      int32_t unused;
+      DCHECK_OK(this->GetOrInsert(other_value, &unused));
+    });
+    return Status::OK();
+  }
+};
+
+template <typename T, typename Enable = void>
+struct HashTraits {};
+
+template <>
+struct HashTraits<BooleanType> {
+  using MemoTableType = SmallScalarMemoTable<bool>;
+};
+
+template <typename T>
+struct HashTraits<T, enable_if_8bit_int<T>> {
+  using c_type = typename T::c_type;
+  using MemoTableType = SmallScalarMemoTable<typename T::c_type>;
+};
+
+template <typename T>
+struct HashTraits<T, enable_if_t<has_c_type<T>::value && !is_8bit_int<T>::value>> {
+  using c_type = typename T::c_type;
+  using MemoTableType = ScalarMemoTable<c_type, HashTable>;
+};
+
+template <typename T>
+struct HashTraits<T, enable_if_t<has_string_view<T>::value &&
+                                 !std::is_base_of<LargeBinaryType, T>::value>> {
+  using MemoTableType = BinaryMemoTable<BinaryBuilder>;
+};
+
+template <typename T>
+struct HashTraits<T, enable_if_decimal<T>> {
+  using MemoTableType = BinaryMemoTable<BinaryBuilder>;
+};
+
+template <typename T>
+struct HashTraits<T, enable_if_t<std::is_base_of<LargeBinaryType, T>::value>> {
+  using MemoTableType = BinaryMemoTable<LargeBinaryBuilder>;
+};
+
+template <typename MemoTableType>
+static inline Status ComputeNullBitmap(MemoryPool* pool, const MemoTableType& memo_table,
+                                       int64_t start_offset, int64_t* null_count,
+                                       std::shared_ptr<Buffer>* null_bitmap) {
+  int64_t dict_length = static_cast<int64_t>(memo_table.size()) - start_offset;
+  int64_t null_index = memo_table.GetNull();
+
+  *null_count = 0;
+  *null_bitmap = nullptr;
+
+  if (null_index != kKeyNotFound && null_index >= start_offset) {
+    null_index -= start_offset;
+    *null_count = 1;
+    ARROW_ASSIGN_OR_RAISE(*null_bitmap,
+                          internal::BitmapAllButOne(pool, dict_length, null_index));
+  }
+
+  return Status::OK();
+}
+
+struct StringViewHash {
+  // std::hash compatible hasher for use with std::unordered_*
+  // (the std::hash specialization provided by nonstd constructs std::string
+  // temporaries then invokes std::hash<std::string> against those)
+  hash_t operator()(std::string_view value) const {
+    return ComputeStringHash<0>(value.data(), static_cast<int64_t>(value.size()));
+  }
+};
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/int_util_overflow.h

@@ -0,0 +1,118 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cstdint>
+#include <limits>
+#include <type_traits>
+
+#include "arrow/status.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+// "safe-math.h" includes <intsafe.h> from the Windows headers.
+#include "arrow/util/windows_compatibility.h"
+#include "arrow/vendored/portable-snippets/safe-math.h"
+// clang-format off (avoid include reordering)
+#include "arrow/util/windows_fixup.h"
+// clang-format on
+
+namespace arrow {
+namespace internal {
+
+// Define functions AddWithOverflow, SubtractWithOverflow, MultiplyWithOverflow
+// with the signature `bool(T u, T v, T* out)` where T is an integer type.
+// On overflow, these functions return true.  Otherwise, false is returned
+// and `out` is updated with the result of the operation.
+
+#define OP_WITH_OVERFLOW(_func_name, _psnip_op, _type, _psnip_type)           \
+  [[nodiscard]] static inline bool _func_name(_type u, _type v, _type* out) { \
+    return !psnip_safe_##_psnip_type##_##_psnip_op(out, u, v);                \
+  }
+
+#define OPS_WITH_OVERFLOW(_func_name, _psnip_op)            \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, int8_t, int8)     \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, int16_t, int16)   \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, int32_t, int32)   \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, int64_t, int64)   \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, uint8_t, uint8)   \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, uint16_t, uint16) \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, uint32_t, uint32) \
+  OP_WITH_OVERFLOW(_func_name, _psnip_op, uint64_t, uint64)
+
+OPS_WITH_OVERFLOW(AddWithOverflow, add)
+OPS_WITH_OVERFLOW(SubtractWithOverflow, sub)
+OPS_WITH_OVERFLOW(MultiplyWithOverflow, mul)
+OPS_WITH_OVERFLOW(DivideWithOverflow, div)
+
+#undef OP_WITH_OVERFLOW
+#undef OPS_WITH_OVERFLOW
+
+// Define function NegateWithOverflow with the signature `bool(T u, T* out)`
+// where T is a signed integer type.  On overflow, these functions return true.
+// Otherwise, false is returned and `out` is updated with the result of the
+// operation.
+
+#define UNARY_OP_WITH_OVERFLOW(_func_name, _psnip_op, _type, _psnip_type) \
+  [[nodiscard]] static inline bool _func_name(_type u, _type* out) {      \
+    return !psnip_safe_##_psnip_type##_##_psnip_op(out, u);               \
+  }
+
+#define SIGNED_UNARY_OPS_WITH_OVERFLOW(_func_name, _psnip_op)   \
+  UNARY_OP_WITH_OVERFLOW(_func_name, _psnip_op, int8_t, int8)   \
+  UNARY_OP_WITH_OVERFLOW(_func_name, _psnip_op, int16_t, int16) \
+  UNARY_OP_WITH_OVERFLOW(_func_name, _psnip_op, int32_t, int32) \
+  UNARY_OP_WITH_OVERFLOW(_func_name, _psnip_op, int64_t, int64)
+
+SIGNED_UNARY_OPS_WITH_OVERFLOW(NegateWithOverflow, neg)
+
+#undef UNARY_OP_WITH_OVERFLOW
+#undef SIGNED_UNARY_OPS_WITH_OVERFLOW
+
+/// Signed addition with well-defined behaviour on overflow (as unsigned)
+template <typename SignedInt>
+SignedInt SafeSignedAdd(SignedInt u, SignedInt v) {
+  using UnsignedInt = typename std::make_unsigned<SignedInt>::type;
+  return static_cast<SignedInt>(static_cast<UnsignedInt>(u) +
+                                static_cast<UnsignedInt>(v));
+}
+
+/// Signed subtraction with well-defined behaviour on overflow (as unsigned)
+template <typename SignedInt>
+SignedInt SafeSignedSubtract(SignedInt u, SignedInt v) {
+  using UnsignedInt = typename std::make_unsigned<SignedInt>::type;
+  return static_cast<SignedInt>(static_cast<UnsignedInt>(u) -
+                                static_cast<UnsignedInt>(v));
+}
+
+/// Signed negation with well-defined behaviour on overflow (as unsigned)
+template <typename SignedInt>
+SignedInt SafeSignedNegate(SignedInt u) {
+  using UnsignedInt = typename std::make_unsigned<SignedInt>::type;
+  return static_cast<SignedInt>(~static_cast<UnsignedInt>(u) + 1);
+}
+
+/// Signed left shift with well-defined behaviour on negative numbers or overflow
+template <typename SignedInt, typename Shift>
+SignedInt SafeLeftShift(SignedInt u, Shift shift) {
+  using UnsignedInt = typename std::make_unsigned<SignedInt>::type;
+  return static_cast<SignedInt>(static_cast<UnsignedInt>(u) << shift);
+}
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/io_util.h

@@ -0,0 +1,452 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#ifndef _WIN32
+#define ARROW_HAVE_SIGACTION 1
+#endif
+
+#include <atomic>
+#include <memory>
+#include <optional>
+#include <string>
+#include <utility>
+#include <vector>
+
+#if ARROW_HAVE_SIGACTION
+#include <csignal>  // Needed for struct sigaction
+#endif
+
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/type_fwd.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/windows_fixup.h"
+
+namespace arrow::internal {
+
+// NOTE: 8-bit path strings on Windows are encoded using UTF-8.
+// Using MBCS would fail encoding some paths.
+
+#if defined(_WIN32)
+using NativePathString = std::wstring;
+#else
+using NativePathString = std::string;
+#endif
+
+class ARROW_EXPORT PlatformFilename {
+ public:
+  struct Impl;
+
+  ~PlatformFilename();
+  PlatformFilename();
+  PlatformFilename(const PlatformFilename&);
+  PlatformFilename(PlatformFilename&&);
+  PlatformFilename& operator=(const PlatformFilename&);
+  PlatformFilename& operator=(PlatformFilename&&);
+  explicit PlatformFilename(NativePathString path);
+  explicit PlatformFilename(const NativePathString::value_type* path);
+
+  const NativePathString& ToNative() const;
+  std::string ToString() const;
+
+  PlatformFilename Parent() const;
+  Result<PlatformFilename> Real() const;
+
+  // These functions can fail for character encoding reasons.
+  static Result<PlatformFilename> FromString(std::string_view file_name);
+  Result<PlatformFilename> Join(std::string_view child_name) const;
+
+  PlatformFilename Join(const PlatformFilename& child_name) const;
+
+  bool operator==(const PlatformFilename& other) const;
+  bool operator!=(const PlatformFilename& other) const;
+
+  // Made public to avoid the proliferation of friend declarations.
+  const Impl* impl() const { return impl_.get(); }
+
+ private:
+  std::unique_ptr<Impl> impl_;
+
+  explicit PlatformFilename(Impl impl);
+};
+
+/// Create a directory if it doesn't exist.
+///
+/// Return whether the directory was created.
+ARROW_EXPORT
+Result<bool> CreateDir(const PlatformFilename& dir_path);
+
+/// Create a directory and its parents if it doesn't exist.
+///
+/// Return whether the directory was created.
+ARROW_EXPORT
+Result<bool> CreateDirTree(const PlatformFilename& dir_path);
+
+/// Delete a directory's contents (but not the directory itself) if it exists.
+///
+/// Return whether the directory existed.
+ARROW_EXPORT
+Result<bool> DeleteDirContents(const PlatformFilename& dir_path,
+                               bool allow_not_found = true);
+
+/// Delete a directory tree if it exists.
+///
+/// Return whether the directory existed.
+ARROW_EXPORT
+Result<bool> DeleteDirTree(const PlatformFilename& dir_path, bool allow_not_found = true);
+
+// Non-recursively list the contents of the given directory.
+// The returned names are the children's base names, not including dir_path.
+ARROW_EXPORT
+Result<std::vector<PlatformFilename>> ListDir(const PlatformFilename& dir_path);
+
+/// Delete a file if it exists.
+///
+/// Return whether the file existed.
+ARROW_EXPORT
+Result<bool> DeleteFile(const PlatformFilename& file_path, bool allow_not_found = true);
+
+/// Return whether a file exists.
+ARROW_EXPORT
+Result<bool> FileExists(const PlatformFilename& path);
+
+// TODO expose this more publicly to make it available from io/file.h?
+/// A RAII wrapper for a file descriptor.
+///
+/// The underlying file descriptor is automatically closed on destruction.
+/// Moving is supported with well-defined semantics.
+/// Furthermore, closing is idempotent.
+class ARROW_EXPORT FileDescriptor {
+ public:
+  FileDescriptor() = default;
+  explicit FileDescriptor(int fd) : fd_(fd) {}
+  FileDescriptor(FileDescriptor&&);
+  FileDescriptor& operator=(FileDescriptor&&);
+
+  ~FileDescriptor();
+
+  Status Close();
+
+  /// May return -1 if closed or default-initialized
+  int fd() const { return fd_.load(); }
+
+  /// Detach and return the underlying file descriptor
+  int Detach();
+
+  bool closed() const { return fd_.load() == -1; }
+
+ protected:
+  static void CloseFromDestructor(int fd);
+
+  std::atomic<int> fd_{-1};
+};
+
+/// Open a file for reading and return a file descriptor.
+ARROW_EXPORT
+Result<FileDescriptor> FileOpenReadable(const PlatformFilename& file_name);
+
+/// Open a file for writing and return a file descriptor.
+ARROW_EXPORT
+Result<FileDescriptor> FileOpenWritable(const PlatformFilename& file_name,
+                                        bool write_only = true, bool truncate = true,
+                                        bool append = false);
+
+/// Read from current file position.  Return number of bytes read.
+ARROW_EXPORT
+Result<int64_t> FileRead(int fd, uint8_t* buffer, int64_t nbytes);
+/// Read from given file position.  Return number of bytes read.
+ARROW_EXPORT
+Result<int64_t> FileReadAt(int fd, uint8_t* buffer, int64_t position, int64_t nbytes);
+
+ARROW_EXPORT
+Status FileWrite(int fd, const uint8_t* buffer, const int64_t nbytes);
+ARROW_EXPORT
+Status FileTruncate(int fd, const int64_t size);
+
+ARROW_EXPORT
+Status FileSeek(int fd, int64_t pos);
+ARROW_EXPORT
+Status FileSeek(int fd, int64_t pos, int whence);
+ARROW_EXPORT
+Result<int64_t> FileTell(int fd);
+ARROW_EXPORT
+Result<int64_t> FileGetSize(int fd);
+
+ARROW_EXPORT
+Status FileClose(int fd);
+
+struct Pipe {
+  FileDescriptor rfd;
+  FileDescriptor wfd;
+
+  Status Close() { return rfd.Close() & wfd.Close(); }
+};
+
+ARROW_EXPORT
+Result<Pipe> CreatePipe();
+
+ARROW_EXPORT
+Status SetPipeFileDescriptorNonBlocking(int fd);
+
+class ARROW_EXPORT SelfPipe {
+ public:
+  static Result<std::shared_ptr<SelfPipe>> Make(bool signal_safe);
+  virtual ~SelfPipe();
+
+  /// \brief Wait for a wakeup.
+  ///
+  /// Status::Invalid is returned if the pipe has been shutdown.
+  /// Otherwise the next sent payload is returned.
+  virtual Result<uint64_t> Wait() = 0;
+
+  /// \brief Wake up the pipe by sending a payload.
+  ///
+  /// This method is async-signal-safe if `signal_safe` was set to true.
+  virtual void Send(uint64_t payload) = 0;
+
+  /// \brief Wake up the pipe and shut it down.
+  virtual Status Shutdown() = 0;
+};
+
+ARROW_EXPORT
+int64_t GetPageSize();
+
+struct MemoryRegion {
+  void* addr;
+  size_t size;
+};
+
+ARROW_EXPORT
+Status MemoryMapRemap(void* addr, size_t old_size, size_t new_size, int fildes,
+                      void** new_addr);
+ARROW_EXPORT
+Status MemoryAdviseWillNeed(const std::vector<MemoryRegion>& regions);
+
+ARROW_EXPORT
+Result<std::string> GetEnvVar(const char* name);
+ARROW_EXPORT
+Result<std::string> GetEnvVar(const std::string& name);
+ARROW_EXPORT
+Result<NativePathString> GetEnvVarNative(const char* name);
+ARROW_EXPORT
+Result<NativePathString> GetEnvVarNative(const std::string& name);
+
+ARROW_EXPORT
+Status SetEnvVar(const char* name, const char* value);
+ARROW_EXPORT
+Status SetEnvVar(const std::string& name, const std::string& value);
+ARROW_EXPORT
+Status DelEnvVar(const char* name);
+ARROW_EXPORT
+Status DelEnvVar(const std::string& name);
+
+ARROW_EXPORT
+std::string ErrnoMessage(int errnum);
+#if _WIN32
+ARROW_EXPORT
+std::string WinErrorMessage(int errnum);
+#endif
+
+ARROW_EXPORT
+std::shared_ptr<StatusDetail> StatusDetailFromErrno(int errnum);
+ARROW_EXPORT
+std::optional<int> ErrnoFromStatusDetail(const StatusDetail& detail);
+#if _WIN32
+ARROW_EXPORT
+std::shared_ptr<StatusDetail> StatusDetailFromWinError(int errnum);
+#endif
+ARROW_EXPORT
+std::shared_ptr<StatusDetail> StatusDetailFromSignal(int signum);
+
+template <typename... Args>
+Status StatusFromErrno(int errnum, StatusCode code, Args&&... args) {
+  return Status::FromDetailAndArgs(code, StatusDetailFromErrno(errnum),
+                                   std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+Status IOErrorFromErrno(int errnum, Args&&... args) {
+  return StatusFromErrno(errnum, StatusCode::IOError, std::forward<Args>(args)...);
+}
+
+#if _WIN32
+template <typename... Args>
+Status StatusFromWinError(int errnum, StatusCode code, Args&&... args) {
+  return Status::FromDetailAndArgs(code, StatusDetailFromWinError(errnum),
+                                   std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+Status IOErrorFromWinError(int errnum, Args&&... args) {
+  return StatusFromWinError(errnum, StatusCode::IOError, std::forward<Args>(args)...);
+}
+#endif
+
+template <typename... Args>
+Status StatusFromSignal(int signum, StatusCode code, Args&&... args) {
+  return Status::FromDetailAndArgs(code, StatusDetailFromSignal(signum),
+                                   std::forward<Args>(args)...);
+}
+
+template <typename... Args>
+Status CancelledFromSignal(int signum, Args&&... args) {
+  return StatusFromSignal(signum, StatusCode::Cancelled, std::forward<Args>(args)...);
+}
+
+ARROW_EXPORT
+int ErrnoFromStatus(const Status&);
+
+// Always returns 0 on non-Windows platforms (for Python).
+ARROW_EXPORT
+int WinErrorFromStatus(const Status&);
+
+ARROW_EXPORT
+int SignalFromStatus(const Status&);
+
+class ARROW_EXPORT TemporaryDir {
+ public:
+  ~TemporaryDir();
+
+  /// '/'-terminated path to the temporary dir
+  const PlatformFilename& path() { return path_; }
+
+  /// Create a temporary subdirectory in the system temporary dir,
+  /// named starting with `prefix`.
+  static Result<std::unique_ptr<TemporaryDir>> Make(const std::string& prefix);
+
+ private:
+  PlatformFilename path_;
+
+  explicit TemporaryDir(PlatformFilename&&);
+};
+
+class ARROW_EXPORT SignalHandler {
+ public:
+  using Callback = void (*)(int);
+
+  SignalHandler();
+  explicit SignalHandler(Callback cb);
+#if ARROW_HAVE_SIGACTION
+  explicit SignalHandler(const struct sigaction& sa);
+#endif
+
+  Callback callback() const;
+#if ARROW_HAVE_SIGACTION
+  const struct sigaction& action() const;
+#endif
+
+ protected:
+#if ARROW_HAVE_SIGACTION
+  // Storing the full sigaction allows to restore the entire signal handling
+  // configuration.
+  struct sigaction sa_;
+#else
+  Callback cb_;
+#endif
+};
+
+/// \brief Return the current handler for the given signal number.
+ARROW_EXPORT
+Result<SignalHandler> GetSignalHandler(int signum);
+
+/// \brief Set a new handler for the given signal number.
+///
+/// The old signal handler is returned.
+ARROW_EXPORT
+Result<SignalHandler> SetSignalHandler(int signum, const SignalHandler& handler);
+
+/// \brief Reinstate the signal handler
+///
+/// For use in signal handlers.  This is needed on platforms without sigaction()
+/// such as Windows, as the default signal handler is restored there as
+/// soon as a signal is raised.
+ARROW_EXPORT
+void ReinstateSignalHandler(int signum, SignalHandler::Callback handler);
+
+/// \brief Send a signal to the current process
+///
+/// The thread which will receive the signal is unspecified.
+ARROW_EXPORT
+Status SendSignal(int signum);
+
+/// \brief Send a signal to the given thread
+///
+/// This function isn't supported on Windows.
+ARROW_EXPORT
+Status SendSignalToThread(int signum, uint64_t thread_id);
+
+/// \brief Get an unpredictable random seed
+///
+/// This function may be slightly costly, so should only be used to initialize
+/// a PRNG, not to generate a large amount of random numbers.
+/// It is better to use this function rather than std::random_device, unless
+/// absolutely necessary (e.g. to generate a cryptographic secret).
+ARROW_EXPORT
+int64_t GetRandomSeed();
+
+/// \brief Get the current thread id
+///
+/// In addition to having the same properties as std::thread, the returned value
+/// is a regular integer value, which is more convenient than an opaque type.
+ARROW_EXPORT
+uint64_t GetThreadId();
+
+/// \brief Get the current memory used by the current process in bytes
+///
+/// This function supports Windows, Linux, and Mac and will return 0 otherwise
+ARROW_EXPORT
+int64_t GetCurrentRSS();
+
+/// \brief Get the total memory available to the system in bytes
+///
+/// This function supports Windows, Linux, and Mac and will return 0 otherwise
+ARROW_EXPORT
+int64_t GetTotalMemoryBytes();
+
+/// \brief Load a dynamic library
+///
+/// This wraps dlopen() except on Windows, where LoadLibrary() is called.
+/// These two platforms handle absolute paths consistently; relative paths
+/// or the library's bare name may be handled but inconsistently.
+///
+/// \return An opaque handle for the dynamic library, which can be used for
+///         subsequent symbol lookup. Nullptr will never be returned; instead
+///         an error will be raised.
+ARROW_EXPORT Result<void*> LoadDynamicLibrary(const PlatformFilename& path);
+
+/// \brief Load a dynamic library
+///
+/// An overload taking null terminated string.
+ARROW_EXPORT Result<void*> LoadDynamicLibrary(const char* path);
+
+/// \brief Retrieve a symbol by name from a library handle.
+///
+/// This wraps dlsym() except on Windows, where GetProcAddress() is called.
+///
+/// \return The address associated with the named symbol. Nullptr will never be
+///         returned; instead an error will be raised.
+ARROW_EXPORT Result<void*> GetSymbol(void* handle, const char* name);
+
+template <typename T>
+Result<T*> GetSymbolAs(void* handle, const char* name) {
+  ARROW_ASSIGN_OR_RAISE(void* sym, GetSymbol(handle, name));
+  return reinterpret_cast<T*>(sym);
+}
+
+}  // namespace arrow::internal

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/iterator.h

@@ -0,0 +1,568 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <cassert>
+#include <functional>
+#include <memory>
+#include <optional>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "arrow/result.h"
+#include "arrow/status.h"
+#include "arrow/util/compare.h"
+#include "arrow/util/functional.h"
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+
+template <typename T>
+class Iterator;
+
+template <typename T>
+struct IterationTraits {
+  /// \brief a reserved value which indicates the end of iteration. By
+  /// default this is NULLPTR since most iterators yield pointer types.
+  /// Specialize IterationTraits if different end semantics are required.
+  ///
+  /// Note: This should not be used to determine if a given value is a
+  /// terminal value.  Use IsIterationEnd (which uses IsEnd) instead.  This
+  /// is only for returning terminal values.
+  static T End() { return T(NULLPTR); }
+
+  /// \brief Checks to see if the value is a terminal value.
+  /// A method is used here since T is not necessarily comparable in many
+  /// cases even though it has a distinct final value
+  static bool IsEnd(const T& val) { return val == End(); }
+};
+
+template <typename T>
+T IterationEnd() {
+  return IterationTraits<T>::End();
+}
+
+template <typename T>
+bool IsIterationEnd(const T& val) {
+  return IterationTraits<T>::IsEnd(val);
+}
+
+template <typename T>
+struct IterationTraits<std::optional<T>> {
+  /// \brief by default when iterating through a sequence of optional,
+  /// nullopt indicates the end of iteration.
+  /// Specialize IterationTraits if different end semantics are required.
+  static std::optional<T> End() { return std::nullopt; }
+
+  /// \brief by default when iterating through a sequence of optional,
+  /// nullopt (!has_value()) indicates the end of iteration.
+  /// Specialize IterationTraits if different end semantics are required.
+  static bool IsEnd(const std::optional<T>& val) { return !val.has_value(); }
+
+  // TODO(bkietz) The range-for loop over Iterator<optional<T>> yields
+  // Result<optional<T>> which is unnecessary (since only the unyielded end optional
+  // is nullopt. Add IterationTraits::GetRangeElement() to handle this case
+};
+
+/// \brief A generic Iterator that can return errors
+template <typename T>
+class Iterator : public util::EqualityComparable<Iterator<T>> {
+ public:
+  /// \brief Iterator may be constructed from any type which has a member function
+  /// with signature Result<T> Next();
+  /// End of iterator is signalled by returning IteratorTraits<T>::End();
+  ///
+  /// The argument is moved or copied to the heap and kept in a unique_ptr<void>. Only
+  /// its destructor and its Next method (which are stored in function pointers) are
+  /// referenced after construction.
+  ///
+  /// This approach is used to dodge MSVC linkage hell (ARROW-6244, ARROW-6558) when using
+  /// an abstract template base class: instead of being inlined as usual for a template
+  /// function the base's virtual destructor will be exported, leading to multiple
+  /// definition errors when linking to any other TU where the base is instantiated.
+  template <typename Wrapped>
+  explicit Iterator(Wrapped has_next)
+      : ptr_(new Wrapped(std::move(has_next)), Delete<Wrapped>), next_(Next<Wrapped>) {}
+
+  Iterator() : ptr_(NULLPTR, [](void*) {}) {}
+
+  /// \brief Return the next element of the sequence, IterationTraits<T>::End() when the
+  /// iteration is completed. Calling this on a default constructed Iterator
+  /// will result in undefined behavior.
+  Result<T> Next() { return next_(ptr_.get()); }
+
+  /// Pass each element of the sequence to a visitor. Will return any error status
+  /// returned by the visitor, terminating iteration.
+  template <typename Visitor>
+  Status Visit(Visitor&& visitor) {
+    for (;;) {
+      ARROW_ASSIGN_OR_RAISE(auto value, Next());
+
+      if (IsIterationEnd(value)) break;
+
+      ARROW_RETURN_NOT_OK(visitor(std::move(value)));
+    }
+
+    return Status::OK();
+  }
+
+  /// Iterators will only compare equal if they are both null.
+  /// Equality comparability is required to make an Iterator of Iterators
+  /// (to check for the end condition).
+  bool Equals(const Iterator& other) const { return ptr_ == other.ptr_; }
+
+  explicit operator bool() const { return ptr_ != NULLPTR; }
+
+  class RangeIterator {
+   public:
+    RangeIterator() : value_(IterationTraits<T>::End()) {}
+
+    explicit RangeIterator(Iterator i)
+        : value_(IterationTraits<T>::End()),
+          iterator_(std::make_shared<Iterator>(std::move(i))) {
+      Next();
+    }
+
+    bool operator!=(const RangeIterator& other) const { return value_ != other.value_; }
+
+    RangeIterator& operator++() {
+      Next();
+      return *this;
+    }
+
+    Result<T> operator*() {
+      ARROW_RETURN_NOT_OK(value_.status());
+
+      auto value = std::move(value_);
+      value_ = IterationTraits<T>::End();
+      return value;
+    }
+
+   private:
+    void Next() {
+      if (!value_.ok()) {
+        value_ = IterationTraits<T>::End();
+        return;
+      }
+      value_ = iterator_->Next();
+    }
+
+    Result<T> value_;
+    std::shared_ptr<Iterator> iterator_;
+  };
+
+  RangeIterator begin() { return RangeIterator(std::move(*this)); }
+
+  RangeIterator end() { return RangeIterator(); }
+
+  /// \brief Move every element of this iterator into a vector.
+  Result<std::vector<T>> ToVector() {
+    std::vector<T> out;
+    for (auto maybe_element : *this) {
+      ARROW_ASSIGN_OR_RAISE(auto element, maybe_element);
+      out.push_back(std::move(element));
+    }
+    // ARROW-8193: On gcc-4.8 without the explicit move it tries to use the
+    // copy constructor, which may be deleted on the elements of type T
+    return std::move(out);
+  }
+
+ private:
+  /// Implementation of deleter for ptr_: Casts from void* to the wrapped type and
+  /// deletes that.
+  template <typename HasNext>
+  static void Delete(void* ptr) {
+    delete static_cast<HasNext*>(ptr);
+  }
+
+  /// Implementation of Next: Casts from void* to the wrapped type and invokes that
+  /// type's Next member function.
+  template <typename HasNext>
+  static Result<T> Next(void* ptr) {
+    return static_cast<HasNext*>(ptr)->Next();
+  }
+
+  /// ptr_ is a unique_ptr to void with a custom deleter: a function pointer which first
+  /// casts from void* to a pointer to the wrapped type then deletes that.
+  std::unique_ptr<void, void (*)(void*)> ptr_;
+
+  /// next_ is a function pointer which first casts from void* to a pointer to the wrapped
+  /// type then invokes its Next member function.
+  Result<T> (*next_)(void*) = NULLPTR;
+};
+
+template <typename T>
+struct TransformFlow {
+  using YieldValueType = T;
+
+  TransformFlow(YieldValueType value, bool ready_for_next)
+      : finished_(false),
+        ready_for_next_(ready_for_next),
+        yield_value_(std::move(value)) {}
+  TransformFlow(bool finished, bool ready_for_next)
+      : finished_(finished), ready_for_next_(ready_for_next), yield_value_() {}
+
+  bool HasValue() const { return yield_value_.has_value(); }
+  bool Finished() const { return finished_; }
+  bool ReadyForNext() const { return ready_for_next_; }
+  T Value() const { return *yield_value_; }
+
+  bool finished_ = false;
+  bool ready_for_next_ = false;
+  std::optional<YieldValueType> yield_value_;
+};
+
+struct TransformFinish {
+  template <typename T>
+  operator TransformFlow<T>() && {  // NOLINT explicit
+    return TransformFlow<T>(true, true);
+  }
+};
+
+struct TransformSkip {
+  template <typename T>
+  operator TransformFlow<T>() && {  // NOLINT explicit
+    return TransformFlow<T>(false, true);
+  }
+};
+
+template <typename T>
+TransformFlow<T> TransformYield(T value = {}, bool ready_for_next = true) {
+  return TransformFlow<T>(std::move(value), ready_for_next);
+}
+
+template <typename T, typename V>
+using Transformer = std::function<Result<TransformFlow<V>>(T)>;
+
+template <typename T, typename V>
+class TransformIterator {
+ public:
+  explicit TransformIterator(Iterator<T> it, Transformer<T, V> transformer)
+      : it_(std::move(it)),
+        transformer_(std::move(transformer)),
+        last_value_(),
+        finished_() {}
+
+  Result<V> Next() {
+    while (!finished_) {
+      ARROW_ASSIGN_OR_RAISE(std::optional<V> next, Pump());
+      if (next.has_value()) {
+        return std::move(*next);
+      }
+      ARROW_ASSIGN_OR_RAISE(last_value_, it_.Next());
+    }
+    return IterationTraits<V>::End();
+  }
+
+ private:
+  // Calls the transform function on the current value.  Can return in several ways
+  // * If the next value is requested (e.g. skip) it will return an empty optional
+  // * If an invalid status is encountered that will be returned
+  // * If finished it will return IterationTraits<V>::End()
+  // * If a value is returned by the transformer that will be returned
+  Result<std::optional<V>> Pump() {
+    if (!finished_ && last_value_.has_value()) {
+      auto next_res = transformer_(*last_value_);
+      if (!next_res.ok()) {
+        finished_ = true;
+        return next_res.status();
+      }
+      auto next = *next_res;
+      if (next.ReadyForNext()) {
+        if (IsIterationEnd(*last_value_)) {
+          finished_ = true;
+        }
+        last_value_.reset();
+      }
+      if (next.Finished()) {
+        finished_ = true;
+      }
+      if (next.HasValue()) {
+        return next.Value();
+      }
+    }
+    if (finished_) {
+      return IterationTraits<V>::End();
+    }
+    return std::nullopt;
+  }
+
+  Iterator<T> it_;
+  Transformer<T, V> transformer_;
+  std::optional<T> last_value_;
+  bool finished_ = false;
+};
+
+/// \brief Transforms an iterator according to a transformer, returning a new Iterator.
+///
+/// The transformer will be called on each element of the source iterator and for each
+/// call it can yield a value, skip, or finish the iteration.  When yielding a value the
+/// transformer can choose to consume the source item (the default, ready_for_next = true)
+/// or to keep it and it will be called again on the same value.
+///
+/// This is essentially a more generic form of the map operation that can return 0, 1, or
+/// many values for each of the source items.
+///
+/// The transformer will be exposed to the end of the source sequence
+/// (IterationTraits::End) in case it needs to return some penultimate item(s).
+///
+/// Any invalid status returned by the transformer will be returned immediately.
+template <typename T, typename V>
+Iterator<V> MakeTransformedIterator(Iterator<T> it, Transformer<T, V> op) {
+  return Iterator<V>(TransformIterator<T, V>(std::move(it), std::move(op)));
+}
+
+template <typename T>
+struct IterationTraits<Iterator<T>> {
+  // The end condition for an Iterator of Iterators is a default constructed (null)
+  // Iterator.
+  static Iterator<T> End() { return Iterator<T>(); }
+  static bool IsEnd(const Iterator<T>& val) { return !val; }
+};
+
+template <typename Fn, typename T>
+class FunctionIterator {
+ public:
+  explicit FunctionIterator(Fn fn) : fn_(std::move(fn)) {}
+
+  Result<T> Next() { return fn_(); }
+
+ private:
+  Fn fn_;
+};
+
+/// \brief Construct an Iterator which invokes a callable on Next()
+template <typename Fn,
+          typename Ret = typename internal::call_traits::return_type<Fn>::ValueType>
+Iterator<Ret> MakeFunctionIterator(Fn fn) {
+  return Iterator<Ret>(FunctionIterator<Fn, Ret>(std::move(fn)));
+}
+
+template <typename T>
+Iterator<T> MakeEmptyIterator() {
+  return MakeFunctionIterator([]() -> Result<T> { return IterationTraits<T>::End(); });
+}
+
+template <typename T>
+Iterator<T> MakeErrorIterator(Status s) {
+  return MakeFunctionIterator([s]() -> Result<T> {
+    ARROW_RETURN_NOT_OK(s);
+    return IterationTraits<T>::End();
+  });
+}
+
+/// \brief Simple iterator which yields the elements of a std::vector
+template <typename T>
+class VectorIterator {
+ public:
+  explicit VectorIterator(std::vector<T> v) : elements_(std::move(v)) {}
+
+  Result<T> Next() {
+    if (i_ == elements_.size()) {
+      return IterationTraits<T>::End();
+    }
+    return std::move(elements_[i_++]);
+  }
+
+ private:
+  std::vector<T> elements_;
+  size_t i_ = 0;
+};
+
+template <typename T>
+Iterator<T> MakeVectorIterator(std::vector<T> v) {
+  return Iterator<T>(VectorIterator<T>(std::move(v)));
+}
+
+/// \brief Simple iterator which yields *pointers* to the elements of a std::vector<T>.
+/// This is provided to support T where IterationTraits<T>::End is not specialized
+template <typename T>
+class VectorPointingIterator {
+ public:
+  explicit VectorPointingIterator(std::vector<T> v) : elements_(std::move(v)) {}
+
+  Result<T*> Next() {
+    if (i_ == elements_.size()) {
+      return NULLPTR;
+    }
+    return &elements_[i_++];
+  }
+
+ private:
+  std::vector<T> elements_;
+  size_t i_ = 0;
+};
+
+template <typename T>
+Iterator<T*> MakeVectorPointingIterator(std::vector<T> v) {
+  return Iterator<T*>(VectorPointingIterator<T>(std::move(v)));
+}
+
+/// \brief MapIterator takes ownership of an iterator and a function to apply
+/// on every element. The mapped function is not allowed to fail.
+template <typename Fn, typename I, typename O>
+class MapIterator {
+ public:
+  explicit MapIterator(Fn map, Iterator<I> it)
+      : map_(std::move(map)), it_(std::move(it)) {}
+
+  Result<O> Next() {
+    ARROW_ASSIGN_OR_RAISE(I i, it_.Next());
+
+    if (IsIterationEnd(i)) {
+      return IterationTraits<O>::End();
+    }
+
+    return map_(std::move(i));
+  }
+
+ private:
+  Fn map_;
+  Iterator<I> it_;
+};
+
+/// \brief MapIterator takes ownership of an iterator and a function to apply
+/// on every element. The mapped function is not allowed to fail.
+template <typename Fn, typename From = internal::call_traits::argument_type<0, Fn>,
+          typename To = internal::call_traits::return_type<Fn>>
+Iterator<To> MakeMapIterator(Fn map, Iterator<From> it) {
+  return Iterator<To>(MapIterator<Fn, From, To>(std::move(map), std::move(it)));
+}
+
+/// \brief Like MapIterator, but where the function can fail.
+template <typename Fn, typename From = internal::call_traits::argument_type<0, Fn>,
+          typename To = typename internal::call_traits::return_type<Fn>::ValueType>
+Iterator<To> MakeMaybeMapIterator(Fn map, Iterator<From> it) {
+  return Iterator<To>(MapIterator<Fn, From, To>(std::move(map), std::move(it)));
+}
+
+struct FilterIterator {
+  enum Action { ACCEPT, REJECT };
+
+  template <typename To>
+  static Result<std::pair<To, Action>> Reject() {
+    return std::make_pair(IterationTraits<To>::End(), REJECT);
+  }
+
+  template <typename To>
+  static Result<std::pair<To, Action>> Accept(To out) {
+    return std::make_pair(std::move(out), ACCEPT);
+  }
+
+  template <typename To>
+  static Result<std::pair<To, Action>> MaybeAccept(Result<To> maybe_out) {
+    return std::move(maybe_out).Map(Accept<To>);
+  }
+
+  template <typename To>
+  static Result<std::pair<To, Action>> Error(Status s) {
+    return s;
+  }
+
+  template <typename Fn, typename From, typename To>
+  class Impl {
+   public:
+    explicit Impl(Fn filter, Iterator<From> it) : filter_(filter), it_(std::move(it)) {}
+
+    Result<To> Next() {
+      To out = IterationTraits<To>::End();
+      Action action;
+
+      for (;;) {
+        ARROW_ASSIGN_OR_RAISE(From i, it_.Next());
+
+        if (IsIterationEnd(i)) {
+          return IterationTraits<To>::End();
+        }
+
+        ARROW_ASSIGN_OR_RAISE(std::tie(out, action), filter_(std::move(i)));
+
+        if (action == ACCEPT) return out;
+      }
+    }
+
+   private:
+    Fn filter_;
+    Iterator<From> it_;
+  };
+};
+
+/// \brief Like MapIterator, but where the function can fail or reject elements.
+template <
+    typename Fn, typename From = typename internal::call_traits::argument_type<0, Fn>,
+    typename Ret = typename internal::call_traits::return_type<Fn>::ValueType,
+    typename To = typename std::tuple_element<0, Ret>::type,
+    typename Enable = typename std::enable_if<std::is_same<
+        typename std::tuple_element<1, Ret>::type, FilterIterator::Action>::value>::type>
+Iterator<To> MakeFilterIterator(Fn filter, Iterator<From> it) {
+  return Iterator<To>(
+      FilterIterator::Impl<Fn, From, To>(std::move(filter), std::move(it)));
+}
+
+/// \brief FlattenIterator takes an iterator generating iterators and yields a
+/// unified iterator that flattens/concatenates in a single stream.
+template <typename T>
+class FlattenIterator {
+ public:
+  explicit FlattenIterator(Iterator<Iterator<T>> it) : parent_(std::move(it)) {}
+
+  Result<T> Next() {
+    if (IsIterationEnd(child_)) {
+      // Pop from parent's iterator.
+      ARROW_ASSIGN_OR_RAISE(child_, parent_.Next());
+
+      // Check if final iteration reached.
+      if (IsIterationEnd(child_)) {
+        return IterationTraits<T>::End();
+      }
+
+      return Next();
+    }
+
+    // Pop from child_ and check for depletion.
+    ARROW_ASSIGN_OR_RAISE(T out, child_.Next());
+    if (IsIterationEnd(out)) {
+      // Reset state such that we pop from parent on the recursive call
+      child_ = IterationTraits<Iterator<T>>::End();
+
+      return Next();
+    }
+
+    return out;
+  }
+
+ private:
+  Iterator<Iterator<T>> parent_;
+  Iterator<T> child_ = IterationTraits<Iterator<T>>::End();
+};
+
+template <typename T>
+Iterator<T> MakeFlattenIterator(Iterator<Iterator<T>> it) {
+  return Iterator<T>(FlattenIterator<T>(std::move(it)));
+}
+
+template <typename Reader>
+Iterator<typename Reader::ValueType> MakeIteratorFromReader(
+    const std::shared_ptr<Reader>& reader) {
+  return MakeFunctionIterator([reader] { return reader->Next(); });
+}
+
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/launder.h

@@ -0,0 +1,35 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#include <new>
+
+namespace arrow {
+namespace internal {
+
+#if __cpp_lib_launder
+using std::launder;
+#else
+template <class T>
+constexpr T* launder(T* p) noexcept {
+  return p;
+}
+#endif
+
+}  // namespace internal
+}  // namespace arrow

venv/lib/python3.10/site-packages/pyarrow/include/arrow/util/logging.h

@@ -0,0 +1,259 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#pragma once
+
+#ifdef GANDIVA_IR
+
+// The LLVM IR code doesn't have an NDEBUG mode. And, it shouldn't include references to
+// streams or stdc++. So, making the DCHECK calls void in that case.
+
+#define ARROW_IGNORE_EXPR(expr) ((void)(expr))
+
+#define DCHECK(condition) ARROW_IGNORE_EXPR(condition)
+#define DCHECK_OK(status) ARROW_IGNORE_EXPR(status)
+#define DCHECK_EQ(val1, val2) ARROW_IGNORE_EXPR(val1)
+#define DCHECK_NE(val1, val2) ARROW_IGNORE_EXPR(val1)
+#define DCHECK_LE(val1, val2) ARROW_IGNORE_EXPR(val1)
+#define DCHECK_LT(val1, val2) ARROW_IGNORE_EXPR(val1)
+#define DCHECK_GE(val1, val2) ARROW_IGNORE_EXPR(val1)
+#define DCHECK_GT(val1, val2) ARROW_IGNORE_EXPR(val1)
+
+#else  // !GANDIVA_IR
+
+#include <memory>
+#include <ostream>
+#include <string>
+
+#include "arrow/util/macros.h"
+#include "arrow/util/visibility.h"
+
+namespace arrow {
+namespace util {
+
+enum class ArrowLogLevel : int {
+  ARROW_DEBUG = -1,
+  ARROW_INFO = 0,
+  ARROW_WARNING = 1,
+  ARROW_ERROR = 2,
+  ARROW_FATAL = 3
+};
+
+#define ARROW_LOG_INTERNAL(level) ::arrow::util::ArrowLog(__FILE__, __LINE__, level)
+#define ARROW_LOG(level) ARROW_LOG_INTERNAL(::arrow::util::ArrowLogLevel::ARROW_##level)
+
+#define ARROW_IGNORE_EXPR(expr) ((void)(expr))
+
+#define ARROW_CHECK_OR_LOG(condition, level) \
+  ARROW_PREDICT_TRUE(condition)              \
+  ? ARROW_IGNORE_EXPR(0)                     \
+  : ::arrow::util::Voidify() & ARROW_LOG(level) << " Check failed: " #condition " "
+
+#define ARROW_CHECK(condition) ARROW_CHECK_OR_LOG(condition, FATAL)
+
+// If 'to_call' returns a bad status, CHECK immediately with a logged message
+// of 'msg' followed by the status.
+#define ARROW_CHECK_OK_PREPEND(to_call, msg, level)                 \
+  do {                                                              \
+    ::arrow::Status _s = (to_call);                                 \
+    ARROW_CHECK_OR_LOG(_s.ok(), level)                              \
+        << "Operation failed: " << ARROW_STRINGIFY(to_call) << "\n" \
+        << (msg) << ": " << _s.ToString();                          \
+  } while (false)
+
+// If the status is bad, CHECK immediately, appending the status to the
+// logged message.
+#define ARROW_CHECK_OK(s) ARROW_CHECK_OK_PREPEND(s, "Bad status", FATAL)
+
+#define ARROW_CHECK_EQ(val1, val2) ARROW_CHECK((val1) == (val2))
+#define ARROW_CHECK_NE(val1, val2) ARROW_CHECK((val1) != (val2))
+#define ARROW_CHECK_LE(val1, val2) ARROW_CHECK((val1) <= (val2))
+#define ARROW_CHECK_LT(val1, val2) ARROW_CHECK((val1) < (val2))
+#define ARROW_CHECK_GE(val1, val2) ARROW_CHECK((val1) >= (val2))
+#define ARROW_CHECK_GT(val1, val2) ARROW_CHECK((val1) > (val2))
+
+#ifdef NDEBUG
+#define ARROW_DFATAL ::arrow::util::ArrowLogLevel::ARROW_WARNING
+
+// CAUTION: DCHECK_OK() always evaluates its argument, but other DCHECK*() macros
+// only do so in debug mode.
+
+#define ARROW_DCHECK(condition)               \
+  while (false) ARROW_IGNORE_EXPR(condition); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_OK(s) \
+  ARROW_IGNORE_EXPR(s);    \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_EQ(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_NE(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_LE(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_LT(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_GE(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+#define ARROW_DCHECK_GT(val1, val2)      \
+  while (false) ARROW_IGNORE_EXPR(val1); \
+  while (false) ARROW_IGNORE_EXPR(val2); \
+  while (false) ::arrow::util::detail::NullLog()
+
+#else
+#define ARROW_DFATAL ::arrow::util::ArrowLogLevel::ARROW_FATAL
+
+#define ARROW_DCHECK ARROW_CHECK
+#define ARROW_DCHECK_OK ARROW_CHECK_OK
+#define ARROW_DCHECK_EQ ARROW_CHECK_EQ
+#define ARROW_DCHECK_NE ARROW_CHECK_NE
+#define ARROW_DCHECK_LE ARROW_CHECK_LE
+#define ARROW_DCHECK_LT ARROW_CHECK_LT
+#define ARROW_DCHECK_GE ARROW_CHECK_GE
+#define ARROW_DCHECK_GT ARROW_CHECK_GT
+
+#endif  // NDEBUG
+
+#define DCHECK ARROW_DCHECK
+#define DCHECK_OK ARROW_DCHECK_OK
+#define DCHECK_EQ ARROW_DCHECK_EQ
+#define DCHECK_NE ARROW_DCHECK_NE
+#define DCHECK_LE ARROW_DCHECK_LE
+#define DCHECK_LT ARROW_DCHECK_LT
+#define DCHECK_GE ARROW_DCHECK_GE
+#define DCHECK_GT ARROW_DCHECK_GT
+
+// This code is adapted from
+// https://github.com/ray-project/ray/blob/master/src/ray/util/logging.h.
+
+// To make the logging lib pluggable with other logging libs and make
+// the implementation unawared by the user, ArrowLog is only a declaration
+// which hide the implementation into logging.cc file.
+// In logging.cc, we can choose different log libs using different macros.
+
+// This is also a null log which does not output anything.
+class ARROW_EXPORT ArrowLogBase {
+ public:
+  virtual ~ArrowLogBase() {}
+
+  virtual bool IsEnabled() const { return false; }
+
+  template <typename T>
+  ArrowLogBase& operator<<(const T& t) {
+    if (IsEnabled()) {
+      Stream() << t;
+    }
+    return *this;
+  }
+
+ protected:
+  virtual std::ostream& Stream() = 0;
+};
+
+class ARROW_EXPORT ArrowLog : public ArrowLogBase {
+ public:
+  ArrowLog(const char* file_name, int line_number, ArrowLogLevel severity);
+  ~ArrowLog() override;
+
+  /// Return whether or not current logging instance is enabled.
+  ///
+  /// \return True if logging is enabled and false otherwise.
+  bool IsEnabled() const override;
+
+  /// The init function of arrow log for a program which should be called only once.
+  ///
+  /// \param appName The app name which starts the log.
+  /// \param severity_threshold Logging threshold for the program.
+  /// \param logDir Logging output file name. If empty, the log won't output to file.
+  static void StartArrowLog(const std::string& appName,
+                            ArrowLogLevel severity_threshold = ArrowLogLevel::ARROW_INFO,
+                            const std::string& logDir = "");
+
+  /// The shutdown function of arrow log, it should be used with StartArrowLog as a pair.
+  static void ShutDownArrowLog();
+
+  /// Install the failure signal handler to output call stack when crash.
+  /// If glog is not installed, this function won't do anything.
+  static void InstallFailureSignalHandler();
+
+  /// Uninstall the signal actions installed by InstallFailureSignalHandler.
+  static void UninstallSignalAction();
+
+  /// Return whether or not the log level is enabled in current setting.
+  ///
+  /// \param log_level The input log level to test.
+  /// \return True if input log level is not lower than the threshold.
+  static bool IsLevelEnabled(ArrowLogLevel log_level);
+
+ private:
+  ARROW_DISALLOW_COPY_AND_ASSIGN(ArrowLog);
+
+  // Hide the implementation of log provider by void *.
+  // Otherwise, lib user may define the same macro to use the correct header file.
+  void* logging_provider_;
+  /// True if log messages should be logged and false if they should be ignored.
+  bool is_enabled_;
+
+  static ArrowLogLevel severity_threshold_;
+
+ protected:
+  std::ostream& Stream() override;
+};
+
+// This class make ARROW_CHECK compilation pass to change the << operator to void.
+// This class is copied from glog.
+class ARROW_EXPORT Voidify {
+ public:
+  Voidify() {}
+  // This has to be an operator with a precedence lower than << but
+  // higher than ?:
+  void operator&(ArrowLogBase&) {}
+};
+
+namespace detail {
+
+/// @brief A helper for the nil log sink.
+///
+/// Using this helper is analogous to sending log messages to /dev/null:
+/// nothing gets logged.
+class NullLog {
+ public:
+  /// The no-op output operator.
+  ///
+  /// @param [in] t
+  ///   The object to send into the nil sink.
+  /// @return Reference to the updated object.
+  template <class T>
+  NullLog& operator<<(const T& t) {
+    return *this;
+  }
+};
+
+}  // namespace detail
+}  // namespace util
+}  // namespace arrow
+
+#endif  // GANDIVA_IR