bazarr/libs/scandir.py

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Python
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2018-10-31 16:08:29 +00:00
"""scandir, a better directory iterator and faster os.walk(), now in the Python 3.5 stdlib
scandir() is a generator version of os.listdir() that returns an
iterator over files in a directory, and also exposes the extra
information most OSes provide while iterating files in a directory
(such as type and stat information).
This module also includes a version of os.walk() that uses scandir()
to speed it up significantly.
See README.md or https://github.com/benhoyt/scandir for rationale and
docs, or read PEP 471 (https://www.python.org/dev/peps/pep-0471/) for
more details on its inclusion into Python 3.5
scandir is released under the new BSD 3-clause license. See
LICENSE.txt for the full license text.
"""
from __future__ import division
from errno import ENOENT
from os import listdir, lstat, stat, strerror
from os.path import join, islink
from stat import S_IFDIR, S_IFLNK, S_IFREG
import collections
import os
import sys
try:
import _scandir
except ImportError:
_scandir = None
try:
import ctypes
except ImportError:
ctypes = None
if _scandir is None and ctypes is None:
import warnings
warnings.warn("scandir can't find the compiled _scandir C module "
"or ctypes, using slow generic fallback")
__version__ = '1.6'
__all__ = ['scandir', 'scandir_generic', 'walk']
# Windows FILE_ATTRIBUTE constants for interpreting the
# FIND_DATA.dwFileAttributes member
FILE_ATTRIBUTE_ARCHIVE = 32
FILE_ATTRIBUTE_COMPRESSED = 2048
FILE_ATTRIBUTE_DEVICE = 64
FILE_ATTRIBUTE_DIRECTORY = 16
FILE_ATTRIBUTE_ENCRYPTED = 16384
FILE_ATTRIBUTE_HIDDEN = 2
FILE_ATTRIBUTE_INTEGRITY_STREAM = 32768
FILE_ATTRIBUTE_NORMAL = 128
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED = 8192
FILE_ATTRIBUTE_NO_SCRUB_DATA = 131072
FILE_ATTRIBUTE_OFFLINE = 4096
FILE_ATTRIBUTE_READONLY = 1
FILE_ATTRIBUTE_REPARSE_POINT = 1024
FILE_ATTRIBUTE_SPARSE_FILE = 512
FILE_ATTRIBUTE_SYSTEM = 4
FILE_ATTRIBUTE_TEMPORARY = 256
FILE_ATTRIBUTE_VIRTUAL = 65536
IS_PY3 = sys.version_info >= (3, 0)
if IS_PY3:
unicode = str # Because Python <= 3.2 doesn't have u'unicode' syntax
class GenericDirEntry(object):
__slots__ = ('name', '_stat', '_lstat', '_scandir_path', '_path')
def __init__(self, scandir_path, name):
self._scandir_path = scandir_path
self.name = name
self._stat = None
self._lstat = None
self._path = None
@property
def path(self):
if self._path is None:
self._path = join(self._scandir_path, self.name)
return self._path
def stat(self, follow_symlinks=True):
if follow_symlinks:
if self._stat is None:
self._stat = stat(self.path)
return self._stat
else:
if self._lstat is None:
self._lstat = lstat(self.path)
return self._lstat
def is_dir(self, follow_symlinks=True):
try:
st = self.stat(follow_symlinks=follow_symlinks)
except OSError as e:
if e.errno != ENOENT:
raise
return False # Path doesn't exist or is a broken symlink
return st.st_mode & 0o170000 == S_IFDIR
def is_file(self, follow_symlinks=True):
try:
st = self.stat(follow_symlinks=follow_symlinks)
except OSError as e:
if e.errno != ENOENT:
raise
return False # Path doesn't exist or is a broken symlink
return st.st_mode & 0o170000 == S_IFREG
def is_symlink(self):
try:
st = self.stat(follow_symlinks=False)
except OSError as e:
if e.errno != ENOENT:
raise
return False # Path doesn't exist or is a broken symlink
return st.st_mode & 0o170000 == S_IFLNK
def inode(self):
st = self.stat(follow_symlinks=False)
return st.st_ino
def __str__(self):
return '<{0}: {1!r}>'.format(self.__class__.__name__, self.name)
__repr__ = __str__
def _scandir_generic(path=unicode('.')):
"""Like os.listdir(), but yield DirEntry objects instead of returning
a list of names.
"""
for name in listdir(path):
yield GenericDirEntry(path, name)
if IS_PY3 and sys.platform == 'win32':
def scandir_generic(path=unicode('.')):
if isinstance(path, bytes):
raise TypeError("os.scandir() doesn't support bytes path on Windows, use Unicode instead")
return _scandir_generic(path)
scandir_generic.__doc__ = _scandir_generic.__doc__
else:
scandir_generic = _scandir_generic
scandir_c = None
scandir_python = None
if sys.platform == 'win32':
if ctypes is not None:
from ctypes import wintypes
# Various constants from windows.h
INVALID_HANDLE_VALUE = ctypes.c_void_p(-1).value
ERROR_FILE_NOT_FOUND = 2
ERROR_NO_MORE_FILES = 18
IO_REPARSE_TAG_SYMLINK = 0xA000000C
# Numer of seconds between 1601-01-01 and 1970-01-01
SECONDS_BETWEEN_EPOCHS = 11644473600
kernel32 = ctypes.windll.kernel32
# ctypes wrappers for (wide string versions of) FindFirstFile,
# FindNextFile, and FindClose
FindFirstFile = kernel32.FindFirstFileW
FindFirstFile.argtypes = [
wintypes.LPCWSTR,
ctypes.POINTER(wintypes.WIN32_FIND_DATAW),
]
FindFirstFile.restype = wintypes.HANDLE
FindNextFile = kernel32.FindNextFileW
FindNextFile.argtypes = [
wintypes.HANDLE,
ctypes.POINTER(wintypes.WIN32_FIND_DATAW),
]
FindNextFile.restype = wintypes.BOOL
FindClose = kernel32.FindClose
FindClose.argtypes = [wintypes.HANDLE]
FindClose.restype = wintypes.BOOL
Win32StatResult = collections.namedtuple('Win32StatResult', [
'st_mode',
'st_ino',
'st_dev',
'st_nlink',
'st_uid',
'st_gid',
'st_size',
'st_atime',
'st_mtime',
'st_ctime',
'st_atime_ns',
'st_mtime_ns',
'st_ctime_ns',
'st_file_attributes',
])
def filetime_to_time(filetime):
"""Convert Win32 FILETIME to time since Unix epoch in seconds."""
total = filetime.dwHighDateTime << 32 | filetime.dwLowDateTime
return total / 10000000 - SECONDS_BETWEEN_EPOCHS
def find_data_to_stat(data):
"""Convert Win32 FIND_DATA struct to stat_result."""
# First convert Win32 dwFileAttributes to st_mode
attributes = data.dwFileAttributes
st_mode = 0
if attributes & FILE_ATTRIBUTE_DIRECTORY:
st_mode |= S_IFDIR | 0o111
else:
st_mode |= S_IFREG
if attributes & FILE_ATTRIBUTE_READONLY:
st_mode |= 0o444
else:
st_mode |= 0o666
if (attributes & FILE_ATTRIBUTE_REPARSE_POINT and
data.dwReserved0 == IO_REPARSE_TAG_SYMLINK):
st_mode ^= st_mode & 0o170000
st_mode |= S_IFLNK
st_size = data.nFileSizeHigh << 32 | data.nFileSizeLow
st_atime = filetime_to_time(data.ftLastAccessTime)
st_mtime = filetime_to_time(data.ftLastWriteTime)
st_ctime = filetime_to_time(data.ftCreationTime)
# Some fields set to zero per CPython's posixmodule.c: st_ino, st_dev,
# st_nlink, st_uid, st_gid
return Win32StatResult(st_mode, 0, 0, 0, 0, 0, st_size,
st_atime, st_mtime, st_ctime,
int(st_atime * 1000000000),
int(st_mtime * 1000000000),
int(st_ctime * 1000000000),
attributes)
class Win32DirEntryPython(object):
__slots__ = ('name', '_stat', '_lstat', '_find_data', '_scandir_path', '_path', '_inode')
def __init__(self, scandir_path, name, find_data):
self._scandir_path = scandir_path
self.name = name
self._stat = None
self._lstat = None
self._find_data = find_data
self._path = None
self._inode = None
@property
def path(self):
if self._path is None:
self._path = join(self._scandir_path, self.name)
return self._path
def stat(self, follow_symlinks=True):
if follow_symlinks:
if self._stat is None:
if self.is_symlink():
# It's a symlink, call link-following stat()
self._stat = stat(self.path)
else:
# Not a symlink, stat is same as lstat value
if self._lstat is None:
self._lstat = find_data_to_stat(self._find_data)
self._stat = self._lstat
return self._stat
else:
if self._lstat is None:
# Lazily convert to stat object, because it's slow
# in Python, and often we only need is_dir() etc
self._lstat = find_data_to_stat(self._find_data)
return self._lstat
def is_dir(self, follow_symlinks=True):
is_symlink = self.is_symlink()
if follow_symlinks and is_symlink:
try:
return self.stat().st_mode & 0o170000 == S_IFDIR
except OSError as e:
if e.errno != ENOENT:
raise
return False
elif is_symlink:
return False
else:
return (self._find_data.dwFileAttributes &
FILE_ATTRIBUTE_DIRECTORY != 0)
def is_file(self, follow_symlinks=True):
is_symlink = self.is_symlink()
if follow_symlinks and is_symlink:
try:
return self.stat().st_mode & 0o170000 == S_IFREG
except OSError as e:
if e.errno != ENOENT:
raise
return False
elif is_symlink:
return False
else:
return (self._find_data.dwFileAttributes &
FILE_ATTRIBUTE_DIRECTORY == 0)
def is_symlink(self):
return (self._find_data.dwFileAttributes &
FILE_ATTRIBUTE_REPARSE_POINT != 0 and
self._find_data.dwReserved0 == IO_REPARSE_TAG_SYMLINK)
def inode(self):
if self._inode is None:
self._inode = lstat(self.path).st_ino
return self._inode
def __str__(self):
return '<{0}: {1!r}>'.format(self.__class__.__name__, self.name)
__repr__ = __str__
def win_error(error, filename):
exc = WindowsError(error, ctypes.FormatError(error))
exc.filename = filename
return exc
def _scandir_python(path=unicode('.')):
"""Like os.listdir(), but yield DirEntry objects instead of returning
a list of names.
"""
# Call FindFirstFile and handle errors
if isinstance(path, bytes):
is_bytes = True
filename = join(path.decode('mbcs', 'strict'), '*.*')
else:
is_bytes = False
filename = join(path, '*.*')
data = wintypes.WIN32_FIND_DATAW()
data_p = ctypes.byref(data)
handle = FindFirstFile(filename, data_p)
if handle == INVALID_HANDLE_VALUE:
error = ctypes.GetLastError()
if error == ERROR_FILE_NOT_FOUND:
# No files, don't yield anything
return
raise win_error(error, path)
# Call FindNextFile in a loop, stopping when no more files
try:
while True:
# Skip '.' and '..' (current and parent directory), but
# otherwise yield (filename, stat_result) tuple
name = data.cFileName
if name not in ('.', '..'):
if is_bytes:
name = name.encode('mbcs', 'replace')
yield Win32DirEntryPython(path, name, data)
data = wintypes.WIN32_FIND_DATAW()
data_p = ctypes.byref(data)
success = FindNextFile(handle, data_p)
if not success:
error = ctypes.GetLastError()
if error == ERROR_NO_MORE_FILES:
break
raise win_error(error, path)
finally:
if not FindClose(handle):
raise win_error(ctypes.GetLastError(), path)
if IS_PY3:
def scandir_python(path=unicode('.')):
if isinstance(path, bytes):
raise TypeError("os.scandir() doesn't support bytes path on Windows, use Unicode instead")
return _scandir_python(path)
scandir_python.__doc__ = _scandir_python.__doc__
else:
scandir_python = _scandir_python
if _scandir is not None:
scandir_c = _scandir.scandir
if _scandir is not None:
scandir = scandir_c
elif ctypes is not None:
scandir = scandir_python
else:
scandir = scandir_generic
# Linux, OS X, and BSD implementation
elif sys.platform.startswith(('linux', 'darwin', 'sunos5')) or 'bsd' in sys.platform:
have_dirent_d_type = (sys.platform != 'sunos5')
if ctypes is not None and have_dirent_d_type:
import ctypes.util
DIR_p = ctypes.c_void_p
# Rather annoying how the dirent struct is slightly different on each
# platform. The only fields we care about are d_name and d_type.
class Dirent(ctypes.Structure):
if sys.platform.startswith('linux'):
_fields_ = (
('d_ino', ctypes.c_ulong),
('d_off', ctypes.c_long),
('d_reclen', ctypes.c_ushort),
('d_type', ctypes.c_byte),
('d_name', ctypes.c_char * 256),
)
else:
_fields_ = (
('d_ino', ctypes.c_uint32), # must be uint32, not ulong
('d_reclen', ctypes.c_ushort),
('d_type', ctypes.c_byte),
('d_namlen', ctypes.c_byte),
('d_name', ctypes.c_char * 256),
)
DT_UNKNOWN = 0
DT_DIR = 4
DT_REG = 8
DT_LNK = 10
Dirent_p = ctypes.POINTER(Dirent)
Dirent_pp = ctypes.POINTER(Dirent_p)
libc = ctypes.CDLL(ctypes.util.find_library('c'), use_errno=True)
opendir = libc.opendir
opendir.argtypes = [ctypes.c_char_p]
opendir.restype = DIR_p
readdir_r = libc.readdir_r
readdir_r.argtypes = [DIR_p, Dirent_p, Dirent_pp]
readdir_r.restype = ctypes.c_int
closedir = libc.closedir
closedir.argtypes = [DIR_p]
closedir.restype = ctypes.c_int
file_system_encoding = sys.getfilesystemencoding()
class PosixDirEntry(object):
__slots__ = ('name', '_d_type', '_stat', '_lstat', '_scandir_path', '_path', '_inode')
def __init__(self, scandir_path, name, d_type, inode):
self._scandir_path = scandir_path
self.name = name
self._d_type = d_type
self._inode = inode
self._stat = None
self._lstat = None
self._path = None
@property
def path(self):
if self._path is None:
self._path = join(self._scandir_path, self.name)
return self._path
def stat(self, follow_symlinks=True):
if follow_symlinks:
if self._stat is None:
if self.is_symlink():
self._stat = stat(self.path)
else:
if self._lstat is None:
self._lstat = lstat(self.path)
self._stat = self._lstat
return self._stat
else:
if self._lstat is None:
self._lstat = lstat(self.path)
return self._lstat
def is_dir(self, follow_symlinks=True):
if (self._d_type == DT_UNKNOWN or
(follow_symlinks and self.is_symlink())):
try:
st = self.stat(follow_symlinks=follow_symlinks)
except OSError as e:
if e.errno != ENOENT:
raise
return False
return st.st_mode & 0o170000 == S_IFDIR
else:
return self._d_type == DT_DIR
def is_file(self, follow_symlinks=True):
if (self._d_type == DT_UNKNOWN or
(follow_symlinks and self.is_symlink())):
try:
st = self.stat(follow_symlinks=follow_symlinks)
except OSError as e:
if e.errno != ENOENT:
raise
return False
return st.st_mode & 0o170000 == S_IFREG
else:
return self._d_type == DT_REG
def is_symlink(self):
if self._d_type == DT_UNKNOWN:
try:
st = self.stat(follow_symlinks=False)
except OSError as e:
if e.errno != ENOENT:
raise
return False
return st.st_mode & 0o170000 == S_IFLNK
else:
return self._d_type == DT_LNK
def inode(self):
return self._inode
def __str__(self):
return '<{0}: {1!r}>'.format(self.__class__.__name__, self.name)
__repr__ = __str__
def posix_error(filename):
errno = ctypes.get_errno()
exc = OSError(errno, strerror(errno))
exc.filename = filename
return exc
def scandir_python(path=unicode('.')):
"""Like os.listdir(), but yield DirEntry objects instead of returning
a list of names.
"""
if isinstance(path, bytes):
opendir_path = path
is_bytes = True
else:
opendir_path = path.encode(file_system_encoding)
is_bytes = False
dir_p = opendir(opendir_path)
if not dir_p:
raise posix_error(path)
try:
result = Dirent_p()
while True:
entry = Dirent()
if readdir_r(dir_p, entry, result):
raise posix_error(path)
if not result:
break
name = entry.d_name
if name not in (b'.', b'..'):
if not is_bytes:
try:
name = name.decode(file_system_encoding)
except UnicodeDecodeError:
try:
name = name.decode("utf-8")
except UnicodeDecodeError:
pass
yield PosixDirEntry(path, name, entry.d_type, entry.d_ino)
finally:
if closedir(dir_p):
raise posix_error(path)
if _scandir is not None:
scandir_c = _scandir.scandir
if _scandir is not None:
scandir = scandir_c
elif ctypes is not None:
scandir = scandir_python
else:
scandir = scandir_generic
# Some other system -- no d_type or stat information
else:
scandir = scandir_generic
def _walk(top, topdown=True, onerror=None, followlinks=False):
"""Like Python 3.5's implementation of os.walk() -- faster than
the pre-Python 3.5 version as it uses scandir() internally.
"""
dirs = []
nondirs = []
# We may not have read permission for top, in which case we can't
# get a list of the files the directory contains. os.walk
# always suppressed the exception then, rather than blow up for a
# minor reason when (say) a thousand readable directories are still
# left to visit. That logic is copied here.
try:
scandir_it = scandir(top)
except OSError as error:
if onerror is not None:
onerror(error)
return
while True:
try:
try:
entry = next(scandir_it)
except StopIteration:
break
except OSError as error:
if onerror is not None:
onerror(error)
return
try:
is_dir = entry.is_dir()
except OSError:
# If is_dir() raises an OSError, consider that the entry is not
# a directory, same behaviour than os.path.isdir().
is_dir = False
if is_dir:
dirs.append(entry.name)
else:
nondirs.append(entry.name)
if not topdown and is_dir:
# Bottom-up: recurse into sub-directory, but exclude symlinks to
# directories if followlinks is False
if followlinks:
walk_into = True
else:
try:
is_symlink = entry.is_symlink()
except OSError:
# If is_symlink() raises an OSError, consider that the
# entry is not a symbolic link, same behaviour than
# os.path.islink().
is_symlink = False
walk_into = not is_symlink
if walk_into:
for entry in walk(entry.path, topdown, onerror, followlinks):
yield entry
# Yield before recursion if going top down
if topdown:
yield top, dirs, nondirs
# Recurse into sub-directories
for name in dirs:
new_path = join(top, name)
# Issue #23605: os.path.islink() is used instead of caching
# entry.is_symlink() result during the loop on os.scandir() because
# the caller can replace the directory entry during the "yield"
# above.
if followlinks or not islink(new_path):
for entry in walk(new_path, topdown, onerror, followlinks):
yield entry
else:
# Yield after recursion if going bottom up
yield top, dirs, nondirs
if IS_PY3 or sys.platform != 'win32':
walk = _walk
else:
# Fix for broken unicode handling on Windows on Python 2.x, see:
# https://github.com/benhoyt/scandir/issues/54
file_system_encoding = sys.getfilesystemencoding()
def walk(top, topdown=True, onerror=None, followlinks=False):
if isinstance(top, bytes):
try:
top = top.decode(file_system_encoding)
except UnicodeDecodeError:
top = top.decode("utf-8")
return _walk(top, topdown, onerror, followlinks)