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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
"""
Like :py:mod:`os.path`, with a reduced set of functions, and with normalized path
separators (always use forward slashes).
Also contains a few additional utilities not found in :py:mod:`os.path`.
"""
import ctypes
import os
import posixpath
import re
import sys
def normsep(path):
"""
Normalize path separators, by using forward slashes instead of whatever
:py:const:`os.sep` is.
"""
if os.sep != "/":
# Python 2 is happy to do things like byte_string.replace(u'foo',
# u'bar'), but not Python 3.
if isinstance(path, bytes):
path = path.replace(os.sep.encode("ascii"), b"/")
else:
path = path.replace(os.sep, "/")
if os.altsep and os.altsep != "/":
if isinstance(path, bytes):
path = path.replace(os.altsep.encode("ascii"), b"/")
else:
path = path.replace(os.altsep, "/")
return path
def cargo_workaround(path):
unc = "//?/"
if path.startswith(unc):
return path[len(unc) :]
return path
def relpath(path, start):
path = normsep(path)
start = normsep(start)
if sys.platform == "win32":
# os.path.relpath can't handle relative paths between UNC and non-UNC
path = cargo_workaround(path)
start = cargo_workaround(start)
try:
rel = os.path.relpath(path, start)
except ValueError:
# On Windows this can throw a ValueError if the two paths are on
# different drives. In that case, just return the path.
return abspath(path)
rel = normsep(rel)
return "" if rel == "." else rel
def realpath(path):
return normsep(os.path.realpath(path))
def abspath(path):
return normsep(os.path.abspath(path))
def join(*paths):
return normsep(os.path.join(*paths))
def normpath(path):
return posixpath.normpath(normsep(path))
def dirname(path):
return posixpath.dirname(normsep(path))
def commonprefix(paths):
return posixpath.commonprefix([normsep(path) for path in paths])
def basename(path):
return os.path.basename(path)
def splitext(path):
return posixpath.splitext(normsep(path))
def split(path):
"""
Return the normalized path as a list of its components.
``split('foo/bar/baz')`` returns ``['foo', 'bar', 'baz']``
"""
return normsep(path).split("/")
def basedir(path, bases):
"""
Given a list of directories (`bases`), return which one contains the given
path. If several matches are found, the deepest base directory is returned.
``basedir('foo/bar/baz', ['foo', 'baz', 'foo/bar'])`` returns ``'foo/bar'``
(`'foo'` and `'foo/bar'` both match, but `'foo/bar'` is the deepest match)
"""
path = normsep(path)
bases = [normsep(b) for b in bases]
if path in bases:
return path
for b in sorted(bases, reverse=True):
if b == "" or path.startswith(b + "/"):
return b
re_cache = {}
# Python versions < 3.7 return r'\/' for re.escape('/').
if re.escape("/") == "/":
MATCH_STAR_STAR_RE = re.compile(r"(^|/)\\\*\\\*/")
MATCH_STAR_STAR_END_RE = re.compile(r"(^|/)\\\*\\\*$")
else:
MATCH_STAR_STAR_RE = re.compile(r"(^|\\\/)\\\*\\\*\\\/")
MATCH_STAR_STAR_END_RE = re.compile(r"(^|\\\/)\\\*\\\*$")
def match(path, pattern):
"""
Return whether the given path matches the given pattern.
An asterisk can be used to match any string, including the null string, in
one part of the path:
``foo`` matches ``*``, ``f*`` or ``fo*o``
However, an asterisk matching a subdirectory may not match the null string:
``foo/bar`` does *not* match ``foo/*/bar``
If the pattern matches one of the ancestor directories of the path, the
patch is considered matching:
``foo/bar`` matches ``foo``
Two adjacent asterisks can be used to match files and zero or more
directories and subdirectories.
``foo/bar`` matches ``foo/**/bar``, or ``**/bar``
"""
if not pattern:
return True
if pattern not in re_cache:
p = re.escape(pattern)
p = MATCH_STAR_STAR_RE.sub(r"\1(?:.+/)?", p)
p = MATCH_STAR_STAR_END_RE.sub(r"(?:\1.+)?", p)
p = p.replace(r"\*", "[^/]*") + "(?:/.*)?$"
re_cache[pattern] = re.compile(p)
return re_cache[pattern].match(path) is not None
def rebase(oldbase, base, relativepath):
"""
Return `relativepath` relative to `base` instead of `oldbase`.
"""
if base == oldbase:
return relativepath
if len(base) < len(oldbase):
assert basedir(oldbase, [base]) == base
relbase = relpath(oldbase, base)
result = join(relbase, relativepath)
else:
assert basedir(base, [oldbase]) == oldbase
relbase = relpath(base, oldbase)
result = relpath(relativepath, relbase)
result = normpath(result)
if relativepath.endswith("/") and not result.endswith("/"):
result += "/"
return result
def readlink(path):
if hasattr(os, "readlink"):
return normsep(os.readlink(path))
# Unfortunately os.path.realpath doesn't support symlinks on Windows, and os.readlink
# is only available on Windows with Python 3.2+. We have to resort to ctypes...
assert sys.platform == "win32"
CreateFileW = ctypes.windll.kernel32.CreateFileW
CreateFileW.argtypes = [
ctypes.wintypes.LPCWSTR,
ctypes.wintypes.DWORD,
ctypes.wintypes.DWORD,
ctypes.wintypes.LPVOID,
ctypes.wintypes.DWORD,
ctypes.wintypes.DWORD,
ctypes.wintypes.HANDLE,
]
CreateFileW.restype = ctypes.wintypes.HANDLE
GENERIC_READ = 0x80000000
FILE_SHARE_READ = 0x00000001
OPEN_EXISTING = 3
FILE_FLAG_BACKUP_SEMANTICS = 0x02000000
handle = CreateFileW(
path,
GENERIC_READ,
FILE_SHARE_READ,
0,
OPEN_EXISTING,
FILE_FLAG_BACKUP_SEMANTICS,
0,
)
assert handle != 1, "Failed getting a handle to: {}".format(path)
MAX_PATH = 260
buf = ctypes.create_unicode_buffer(MAX_PATH)
GetFinalPathNameByHandleW = ctypes.windll.kernel32.GetFinalPathNameByHandleW
GetFinalPathNameByHandleW.argtypes = [
ctypes.wintypes.HANDLE,
ctypes.wintypes.LPWSTR,
ctypes.wintypes.DWORD,
ctypes.wintypes.DWORD,
]
GetFinalPathNameByHandleW.restype = ctypes.wintypes.DWORD
FILE_NAME_NORMALIZED = 0x0
rv = GetFinalPathNameByHandleW(handle, buf, MAX_PATH, FILE_NAME_NORMALIZED)
assert rv != 0 and rv <= MAX_PATH, "Failed getting final path for: {}".format(path)
CloseHandle = ctypes.windll.kernel32.CloseHandle
CloseHandle.argtypes = [ctypes.wintypes.HANDLE]
CloseHandle.restype = ctypes.wintypes.BOOL
rv = CloseHandle(handle)
assert rv != 0, "Failed closing handle"
# Remove leading '\\?\' from the result.
return normsep(buf.value[4:])