File size: 15,349 Bytes
6db9ec4 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 |
# Copyright (c) 2009, Giampaolo Rodola'. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Module which provides compatibility with older Python versions.
This is more future-compatible rather than the opposite (prefer latest
Python 3 way of doing things).
"""
import collections
import contextlib
import errno
import functools
import os
import sys
import types
# fmt: off
__all__ = [
# constants
"PY3",
# builtins
"long", "range", "super", "unicode", "basestring",
# literals
"u", "b",
# collections module
"lru_cache",
# shutil module
"which", "get_terminal_size",
# contextlib module
"redirect_stderr",
# python 3 exceptions
"FileNotFoundError", "PermissionError", "ProcessLookupError",
"InterruptedError", "ChildProcessError", "FileExistsError",
]
# fmt: on
PY3 = sys.version_info[0] >= 3
_SENTINEL = object()
if PY3:
long = int
xrange = range
unicode = str
basestring = str
range = range
def u(s):
return s
def b(s):
return s.encode("latin-1")
else:
long = long
range = xrange
unicode = unicode
basestring = basestring
def u(s):
return unicode(s, "unicode_escape")
def b(s):
return s
# --- builtins
# Python 3 super().
# Taken from "future" package.
# Credit: Ryan Kelly
if PY3:
super = super
else:
_builtin_super = super
def super(type_=_SENTINEL, type_or_obj=_SENTINEL, framedepth=1):
"""Like Python 3 builtin super(). If called without any arguments
it attempts to infer them at runtime.
"""
if type_ is _SENTINEL:
f = sys._getframe(framedepth)
try:
# Get the function's first positional argument.
type_or_obj = f.f_locals[f.f_code.co_varnames[0]]
except (IndexError, KeyError):
msg = 'super() used in a function with no args'
raise RuntimeError(msg)
try:
# Get the MRO so we can crawl it.
mro = type_or_obj.__mro__
except (AttributeError, RuntimeError):
try:
mro = type_or_obj.__class__.__mro__
except AttributeError:
msg = 'super() used in a non-newstyle class'
raise RuntimeError(msg)
for type_ in mro:
# Find the class that owns the currently-executing method.
for meth in type_.__dict__.values():
# Drill down through any wrappers to the underlying func.
# This handles e.g. classmethod() and staticmethod().
try:
while not isinstance(meth, types.FunctionType):
if isinstance(meth, property):
# Calling __get__ on the property will invoke
# user code which might throw exceptions or
# have side effects
meth = meth.fget
else:
try:
meth = meth.__func__
except AttributeError:
meth = meth.__get__(type_or_obj, type_)
except (AttributeError, TypeError):
continue
if meth.func_code is f.f_code:
break # found
else:
# Not found. Move onto the next class in MRO.
continue
break # found
else:
msg = 'super() called outside a method'
raise RuntimeError(msg)
# Dispatch to builtin super().
if type_or_obj is not _SENTINEL:
return _builtin_super(type_, type_or_obj)
return _builtin_super(type_)
# --- exceptions
if PY3:
FileNotFoundError = FileNotFoundError # NOQA
PermissionError = PermissionError # NOQA
ProcessLookupError = ProcessLookupError # NOQA
InterruptedError = InterruptedError # NOQA
ChildProcessError = ChildProcessError # NOQA
FileExistsError = FileExistsError # NOQA
else:
# https://github.com/PythonCharmers/python-future/blob/exceptions/
# src/future/types/exceptions/pep3151.py
import platform
def _instance_checking_exception(base_exception=Exception):
def wrapped(instance_checker):
class TemporaryClass(base_exception):
def __init__(self, *args, **kwargs):
if len(args) == 1 and isinstance(args[0], TemporaryClass):
unwrap_me = args[0]
for attr in dir(unwrap_me):
if not attr.startswith('__'):
setattr(self, attr, getattr(unwrap_me, attr))
else:
super(TemporaryClass, self).__init__( # noqa
*args, **kwargs
)
class __metaclass__(type):
def __instancecheck__(cls, inst):
return instance_checker(inst)
def __subclasscheck__(cls, classinfo):
value = sys.exc_info()[1]
return isinstance(value, cls)
TemporaryClass.__name__ = instance_checker.__name__
TemporaryClass.__doc__ = instance_checker.__doc__
return TemporaryClass
return wrapped
@_instance_checking_exception(EnvironmentError)
def FileNotFoundError(inst):
return getattr(inst, 'errno', _SENTINEL) == errno.ENOENT
@_instance_checking_exception(EnvironmentError)
def ProcessLookupError(inst):
return getattr(inst, 'errno', _SENTINEL) == errno.ESRCH
@_instance_checking_exception(EnvironmentError)
def PermissionError(inst):
return getattr(inst, 'errno', _SENTINEL) in (errno.EACCES, errno.EPERM)
@_instance_checking_exception(EnvironmentError)
def InterruptedError(inst):
return getattr(inst, 'errno', _SENTINEL) == errno.EINTR
@_instance_checking_exception(EnvironmentError)
def ChildProcessError(inst):
return getattr(inst, 'errno', _SENTINEL) == errno.ECHILD
@_instance_checking_exception(EnvironmentError)
def FileExistsError(inst):
return getattr(inst, 'errno', _SENTINEL) == errno.EEXIST
if platform.python_implementation() != "CPython":
try:
raise OSError(errno.EEXIST, "perm")
except FileExistsError:
pass
except OSError:
msg = (
"broken or incompatible Python implementation, see: "
"https://github.com/giampaolo/psutil/issues/1659"
)
raise RuntimeError(msg)
# --- stdlib additions
# py 3.2 functools.lru_cache
# Taken from: http://code.activestate.com/recipes/578078
# Credit: Raymond Hettinger
try:
from functools import lru_cache
except ImportError:
try:
from threading import RLock
except ImportError:
from dummy_threading import RLock
_CacheInfo = collections.namedtuple(
"CacheInfo", ["hits", "misses", "maxsize", "currsize"]
)
class _HashedSeq(list):
__slots__ = ('hashvalue',)
def __init__(self, tup, hash=hash):
self[:] = tup
self.hashvalue = hash(tup)
def __hash__(self):
return self.hashvalue
def _make_key(
args,
kwds,
typed,
kwd_mark=(_SENTINEL,),
fasttypes=set((int, str, frozenset, type(None))), # noqa
sorted=sorted,
tuple=tuple,
type=type,
len=len,
):
key = args
if kwds:
sorted_items = sorted(kwds.items())
key += kwd_mark
for item in sorted_items:
key += item
if typed:
key += tuple(type(v) for v in args)
if kwds:
key += tuple(type(v) for k, v in sorted_items)
elif len(key) == 1 and type(key[0]) in fasttypes:
return key[0]
return _HashedSeq(key)
def lru_cache(maxsize=100, typed=False):
"""Least-recently-used cache decorator, see:
http://docs.python.org/3/library/functools.html#functools.lru_cache.
"""
def decorating_function(user_function):
cache = {}
stats = [0, 0]
HITS, MISSES = 0, 1
make_key = _make_key
cache_get = cache.get
_len = len
lock = RLock()
root = []
root[:] = [root, root, None, None]
nonlocal_root = [root]
PREV, NEXT, KEY, RESULT = 0, 1, 2, 3
if maxsize == 0:
def wrapper(*args, **kwds):
result = user_function(*args, **kwds)
stats[MISSES] += 1
return result
elif maxsize is None:
def wrapper(*args, **kwds):
key = make_key(args, kwds, typed)
result = cache_get(key, root)
if result is not root:
stats[HITS] += 1
return result
result = user_function(*args, **kwds)
cache[key] = result
stats[MISSES] += 1
return result
else:
def wrapper(*args, **kwds):
if kwds or typed:
key = make_key(args, kwds, typed)
else:
key = args
lock.acquire()
try:
link = cache_get(key)
if link is not None:
(root,) = nonlocal_root
link_prev, link_next, key, result = link
link_prev[NEXT] = link_next
link_next[PREV] = link_prev
last = root[PREV]
last[NEXT] = root[PREV] = link
link[PREV] = last
link[NEXT] = root
stats[HITS] += 1
return result
finally:
lock.release()
result = user_function(*args, **kwds)
lock.acquire()
try:
(root,) = nonlocal_root
if key in cache:
pass
elif _len(cache) >= maxsize:
oldroot = root
oldroot[KEY] = key
oldroot[RESULT] = result
root = nonlocal_root[0] = oldroot[NEXT]
oldkey = root[KEY]
root[KEY] = root[RESULT] = None
del cache[oldkey]
cache[key] = oldroot
else:
last = root[PREV]
link = [last, root, key, result]
last[NEXT] = root[PREV] = cache[key] = link
stats[MISSES] += 1
finally:
lock.release()
return result
def cache_info():
"""Report cache statistics."""
lock.acquire()
try:
return _CacheInfo(
stats[HITS], stats[MISSES], maxsize, len(cache)
)
finally:
lock.release()
def cache_clear():
"""Clear the cache and cache statistics."""
lock.acquire()
try:
cache.clear()
root = nonlocal_root[0]
root[:] = [root, root, None, None]
stats[:] = [0, 0]
finally:
lock.release()
wrapper.__wrapped__ = user_function
wrapper.cache_info = cache_info
wrapper.cache_clear = cache_clear
return functools.update_wrapper(wrapper, user_function)
return decorating_function
# python 3.3
try:
from shutil import which
except ImportError:
def which(cmd, mode=os.F_OK | os.X_OK, path=None):
"""Given a command, mode, and a PATH string, return the path which
conforms to the given mode on the PATH, or None if there is no such
file.
`mode` defaults to os.F_OK | os.X_OK. `path` defaults to the result
of os.environ.get("PATH"), or can be overridden with a custom search
path.
"""
def _access_check(fn, mode):
return (
os.path.exists(fn)
and os.access(fn, mode)
and not os.path.isdir(fn)
)
if os.path.dirname(cmd):
if _access_check(cmd, mode):
return cmd
return None
if path is None:
path = os.environ.get("PATH", os.defpath)
if not path:
return None
path = path.split(os.pathsep)
if sys.platform == "win32":
if os.curdir not in path:
path.insert(0, os.curdir)
pathext = os.environ.get("PATHEXT", "").split(os.pathsep)
if any(cmd.lower().endswith(ext.lower()) for ext in pathext):
files = [cmd]
else:
files = [cmd + ext for ext in pathext]
else:
files = [cmd]
seen = set()
for dir in path:
normdir = os.path.normcase(dir)
if normdir not in seen:
seen.add(normdir)
for thefile in files:
name = os.path.join(dir, thefile)
if _access_check(name, mode):
return name
return None
# python 3.3
try:
from shutil import get_terminal_size
except ImportError:
def get_terminal_size(fallback=(80, 24)):
try:
import fcntl
import struct
import termios
except ImportError:
return fallback
else:
try:
# This should work on Linux.
res = struct.unpack(
'hh', fcntl.ioctl(1, termios.TIOCGWINSZ, '1234')
)
return (res[1], res[0])
except Exception: # noqa: BLE001
return fallback
# python 3.3
try:
from subprocess import TimeoutExpired as SubprocessTimeoutExpired
except ImportError:
class SubprocessTimeoutExpired(Exception):
pass
# python 3.5
try:
from contextlib import redirect_stderr
except ImportError:
@contextlib.contextmanager
def redirect_stderr(new_target):
original = sys.stderr
try:
sys.stderr = new_target
yield new_target
finally:
sys.stderr = original
|