mirror of
https://github.com/python/cpython.git
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c7f02a9659
bpo-33671 * use memoryview() with size == file size on Windows, see https://github.com/python/cpython/pull/7160#discussion_r195405230 * release intermediate (sliced) memoryview immediately * replace "OSX" occurrences with "macOS" * add some unittests for copyfileobj()
1309 lines
45 KiB
Python
1309 lines
45 KiB
Python
"""Utility functions for copying and archiving files and directory trees.
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XXX The functions here don't copy the resource fork or other metadata on Mac.
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"""
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import os
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import sys
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import stat
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import fnmatch
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import collections
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import errno
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import io
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try:
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import zlib
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del zlib
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_ZLIB_SUPPORTED = True
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except ImportError:
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_ZLIB_SUPPORTED = False
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try:
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import bz2
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del bz2
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_BZ2_SUPPORTED = True
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except ImportError:
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_BZ2_SUPPORTED = False
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try:
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import lzma
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del lzma
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_LZMA_SUPPORTED = True
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except ImportError:
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_LZMA_SUPPORTED = False
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try:
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from pwd import getpwnam
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except ImportError:
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getpwnam = None
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try:
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from grp import getgrnam
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except ImportError:
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getgrnam = None
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_WINDOWS = os.name == 'nt'
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posix = nt = None
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if os.name == 'posix':
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import posix
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elif _WINDOWS:
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import nt
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COPY_BUFSIZE = 1024 * 1024 if _WINDOWS else 16 * 1024
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_HAS_SENDFILE = posix and hasattr(os, "sendfile")
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_HAS_FCOPYFILE = posix and hasattr(posix, "_fcopyfile") # macOS
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__all__ = ["copyfileobj", "copyfile", "copymode", "copystat", "copy", "copy2",
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"copytree", "move", "rmtree", "Error", "SpecialFileError",
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"ExecError", "make_archive", "get_archive_formats",
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"register_archive_format", "unregister_archive_format",
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"get_unpack_formats", "register_unpack_format",
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"unregister_unpack_format", "unpack_archive",
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"ignore_patterns", "chown", "which", "get_terminal_size",
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"SameFileError"]
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# disk_usage is added later, if available on the platform
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class Error(OSError):
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pass
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class SameFileError(Error):
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"""Raised when source and destination are the same file."""
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class SpecialFileError(OSError):
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"""Raised when trying to do a kind of operation (e.g. copying) which is
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not supported on a special file (e.g. a named pipe)"""
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class ExecError(OSError):
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"""Raised when a command could not be executed"""
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class ReadError(OSError):
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"""Raised when an archive cannot be read"""
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class RegistryError(Exception):
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"""Raised when a registry operation with the archiving
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and unpacking registries fails"""
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class _GiveupOnFastCopy(Exception):
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"""Raised as a signal to fallback on using raw read()/write()
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file copy when fast-copy functions fail to do so.
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"""
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def _fastcopy_fcopyfile(fsrc, fdst, flags):
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"""Copy a regular file content or metadata by using high-performance
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fcopyfile(3) syscall (macOS).
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"""
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try:
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infd = fsrc.fileno()
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outfd = fdst.fileno()
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except Exception as err:
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raise _GiveupOnFastCopy(err) # not a regular file
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try:
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posix._fcopyfile(infd, outfd, flags)
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except OSError as err:
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err.filename = fsrc.name
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err.filename2 = fdst.name
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if err.errno in {errno.EINVAL, errno.ENOTSUP}:
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raise _GiveupOnFastCopy(err)
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else:
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raise err from None
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def _fastcopy_sendfile(fsrc, fdst):
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"""Copy data from one regular mmap-like fd to another by using
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high-performance sendfile(2) syscall.
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This should work on Linux >= 2.6.33 and Solaris only.
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"""
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# Note: copyfileobj() is left alone in order to not introduce any
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# unexpected breakage. Possible risks by using zero-copy calls
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# in copyfileobj() are:
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# - fdst cannot be open in "a"(ppend) mode
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# - fsrc and fdst may be open in "t"(ext) mode
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# - fsrc may be a BufferedReader (which hides unread data in a buffer),
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# GzipFile (which decompresses data), HTTPResponse (which decodes
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# chunks).
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# - possibly others (e.g. encrypted fs/partition?)
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global _HAS_SENDFILE
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try:
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infd = fsrc.fileno()
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outfd = fdst.fileno()
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except Exception as err:
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raise _GiveupOnFastCopy(err) # not a regular file
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# Hopefully the whole file will be copied in a single call.
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# sendfile() is called in a loop 'till EOF is reached (0 return)
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# so a bufsize smaller or bigger than the actual file size
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# should not make any difference, also in case the file content
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# changes while being copied.
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try:
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blocksize = max(os.fstat(infd).st_size, 2 ** 23) # min 8MB
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except Exception:
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blocksize = 2 ** 27 # 128MB
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offset = 0
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while True:
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try:
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sent = os.sendfile(outfd, infd, offset, blocksize)
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except OSError as err:
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# ...in oder to have a more informative exception.
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err.filename = fsrc.name
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err.filename2 = fdst.name
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if err.errno == errno.ENOTSOCK:
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# sendfile() on this platform (probably Linux < 2.6.33)
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# does not support copies between regular files (only
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# sockets).
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_HAS_SENDFILE = False
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raise _GiveupOnFastCopy(err)
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if err.errno == errno.ENOSPC: # filesystem is full
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raise err from None
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# Give up on first call and if no data was copied.
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if offset == 0 and os.lseek(outfd, 0, os.SEEK_CUR) == 0:
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raise _GiveupOnFastCopy(err)
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raise err
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else:
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if sent == 0:
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break # EOF
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offset += sent
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def _copyfileobj_readinto(fsrc, fdst, length=COPY_BUFSIZE):
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"""readinto()/memoryview() based variant of copyfileobj().
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*fsrc* must support readinto() method and both files must be
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open in binary mode.
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"""
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# Localize variable access to minimize overhead.
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fsrc_readinto = fsrc.readinto
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fdst_write = fdst.write
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with memoryview(bytearray(length)) as mv:
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while True:
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n = fsrc_readinto(mv)
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if not n:
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break
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elif n < length:
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with mv[:n] as smv:
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fdst.write(smv)
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else:
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fdst_write(mv)
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def copyfileobj(fsrc, fdst, length=COPY_BUFSIZE):
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"""copy data from file-like object fsrc to file-like object fdst"""
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# Localize variable access to minimize overhead.
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fsrc_read = fsrc.read
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fdst_write = fdst.write
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while True:
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buf = fsrc_read(length)
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if not buf:
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break
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fdst_write(buf)
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def _samefile(src, dst):
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# Macintosh, Unix.
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if hasattr(os.path, 'samefile'):
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try:
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return os.path.samefile(src, dst)
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except OSError:
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return False
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# All other platforms: check for same pathname.
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return (os.path.normcase(os.path.abspath(src)) ==
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os.path.normcase(os.path.abspath(dst)))
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def copyfile(src, dst, *, follow_symlinks=True):
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"""Copy data from src to dst in the most efficient way possible.
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If follow_symlinks is not set and src is a symbolic link, a new
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symlink will be created instead of copying the file it points to.
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"""
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if _samefile(src, dst):
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raise SameFileError("{!r} and {!r} are the same file".format(src, dst))
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file_size = 0
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for i, fn in enumerate([src, dst]):
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try:
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st = os.stat(fn)
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except OSError:
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# File most likely does not exist
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pass
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else:
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# XXX What about other special files? (sockets, devices...)
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if stat.S_ISFIFO(st.st_mode):
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raise SpecialFileError("`%s` is a named pipe" % fn)
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if _WINDOWS and i == 0:
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file_size = st.st_size
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if not follow_symlinks and os.path.islink(src):
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os.symlink(os.readlink(src), dst)
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else:
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with open(src, 'rb') as fsrc, open(dst, 'wb') as fdst:
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# macOS
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if _HAS_FCOPYFILE:
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try:
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_fastcopy_fcopyfile(fsrc, fdst, posix._COPYFILE_DATA)
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return dst
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except _GiveupOnFastCopy:
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pass
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# Linux / Solaris
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elif _HAS_SENDFILE:
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try:
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_fastcopy_sendfile(fsrc, fdst)
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return dst
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except _GiveupOnFastCopy:
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pass
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# Windows, see:
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# https://github.com/python/cpython/pull/7160#discussion_r195405230
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elif _WINDOWS and file_size > 0:
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_copyfileobj_readinto(fsrc, fdst, min(file_size, COPY_BUFSIZE))
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return dst
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copyfileobj(fsrc, fdst)
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return dst
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def copymode(src, dst, *, follow_symlinks=True):
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"""Copy mode bits from src to dst.
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If follow_symlinks is not set, symlinks aren't followed if and only
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if both `src` and `dst` are symlinks. If `lchmod` isn't available
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(e.g. Linux) this method does nothing.
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"""
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if not follow_symlinks and os.path.islink(src) and os.path.islink(dst):
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if hasattr(os, 'lchmod'):
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stat_func, chmod_func = os.lstat, os.lchmod
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else:
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return
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elif hasattr(os, 'chmod'):
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stat_func, chmod_func = os.stat, os.chmod
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else:
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return
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st = stat_func(src)
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chmod_func(dst, stat.S_IMODE(st.st_mode))
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if hasattr(os, 'listxattr'):
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def _copyxattr(src, dst, *, follow_symlinks=True):
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"""Copy extended filesystem attributes from `src` to `dst`.
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Overwrite existing attributes.
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If `follow_symlinks` is false, symlinks won't be followed.
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"""
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try:
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names = os.listxattr(src, follow_symlinks=follow_symlinks)
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except OSError as e:
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if e.errno not in (errno.ENOTSUP, errno.ENODATA):
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raise
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return
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for name in names:
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try:
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value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
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os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
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except OSError as e:
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if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
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raise
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else:
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def _copyxattr(*args, **kwargs):
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pass
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def copystat(src, dst, *, follow_symlinks=True):
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"""Copy all stat info (mode bits, atime, mtime, flags) from src to dst.
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If the optional flag `follow_symlinks` is not set, symlinks aren't followed if and
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only if both `src` and `dst` are symlinks.
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"""
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def _nop(*args, ns=None, follow_symlinks=None):
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pass
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# follow symlinks (aka don't not follow symlinks)
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follow = follow_symlinks or not (os.path.islink(src) and os.path.islink(dst))
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if follow:
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# use the real function if it exists
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def lookup(name):
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return getattr(os, name, _nop)
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else:
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# use the real function only if it exists
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# *and* it supports follow_symlinks
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def lookup(name):
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fn = getattr(os, name, _nop)
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if fn in os.supports_follow_symlinks:
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return fn
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return _nop
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st = lookup("stat")(src, follow_symlinks=follow)
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mode = stat.S_IMODE(st.st_mode)
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lookup("utime")(dst, ns=(st.st_atime_ns, st.st_mtime_ns),
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follow_symlinks=follow)
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try:
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lookup("chmod")(dst, mode, follow_symlinks=follow)
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except NotImplementedError:
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# if we got a NotImplementedError, it's because
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# * follow_symlinks=False,
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# * lchown() is unavailable, and
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# * either
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# * fchownat() is unavailable or
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# * fchownat() doesn't implement AT_SYMLINK_NOFOLLOW.
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# (it returned ENOSUP.)
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# therefore we're out of options--we simply cannot chown the
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# symlink. give up, suppress the error.
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# (which is what shutil always did in this circumstance.)
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pass
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if hasattr(st, 'st_flags'):
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try:
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lookup("chflags")(dst, st.st_flags, follow_symlinks=follow)
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except OSError as why:
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for err in 'EOPNOTSUPP', 'ENOTSUP':
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if hasattr(errno, err) and why.errno == getattr(errno, err):
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break
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else:
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raise
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_copyxattr(src, dst, follow_symlinks=follow)
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def copy(src, dst, *, follow_symlinks=True):
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"""Copy data and mode bits ("cp src dst"). Return the file's destination.
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The destination may be a directory.
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If follow_symlinks is false, symlinks won't be followed. This
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resembles GNU's "cp -P src dst".
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If source and destination are the same file, a SameFileError will be
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raised.
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"""
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if os.path.isdir(dst):
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dst = os.path.join(dst, os.path.basename(src))
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copyfile(src, dst, follow_symlinks=follow_symlinks)
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copymode(src, dst, follow_symlinks=follow_symlinks)
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return dst
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def copy2(src, dst, *, follow_symlinks=True):
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"""Copy data and all stat info ("cp -p src dst"). Return the file's
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destination.
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The destination may be a directory.
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If follow_symlinks is false, symlinks won't be followed. This
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resembles GNU's "cp -P src dst".
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"""
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if os.path.isdir(dst):
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dst = os.path.join(dst, os.path.basename(src))
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copyfile(src, dst, follow_symlinks=follow_symlinks)
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copystat(src, dst, follow_symlinks=follow_symlinks)
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return dst
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|
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def ignore_patterns(*patterns):
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"""Function that can be used as copytree() ignore parameter.
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Patterns is a sequence of glob-style patterns
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that are used to exclude files"""
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def _ignore_patterns(path, names):
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ignored_names = []
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for pattern in patterns:
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ignored_names.extend(fnmatch.filter(names, pattern))
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return set(ignored_names)
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return _ignore_patterns
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|
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def copytree(src, dst, symlinks=False, ignore=None, copy_function=copy2,
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ignore_dangling_symlinks=False):
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"""Recursively copy a directory tree.
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The destination directory must not already exist.
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If exception(s) occur, an Error is raised with a list of reasons.
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|
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If the optional symlinks flag is true, symbolic links in the
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source tree result in symbolic links in the destination tree; if
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it is false, the contents of the files pointed to by symbolic
|
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links are copied. If the file pointed by the symlink doesn't
|
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exist, an exception will be added in the list of errors raised in
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an Error exception at the end of the copy process.
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|
|
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You can set the optional ignore_dangling_symlinks flag to true if you
|
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want to silence this exception. Notice that this has no effect on
|
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platforms that don't support os.symlink.
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|
|
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The optional ignore argument is a callable. If given, it
|
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is called with the `src` parameter, which is the directory
|
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being visited by copytree(), and `names` which is the list of
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`src` contents, as returned by os.listdir():
|
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|
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callable(src, names) -> ignored_names
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|
|
Since copytree() is called recursively, the callable will be
|
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called once for each directory that is copied. It returns a
|
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list of names relative to the `src` directory that should
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not be copied.
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|
|
|
The optional copy_function argument is a callable that will be used
|
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to copy each file. It will be called with the source path and the
|
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destination path as arguments. By default, copy2() is used, but any
|
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function that supports the same signature (like copy()) can be used.
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|
|
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"""
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names = os.listdir(src)
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if ignore is not None:
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ignored_names = ignore(src, names)
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else:
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ignored_names = set()
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|
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os.makedirs(dst)
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errors = []
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for name in names:
|
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if name in ignored_names:
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continue
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srcname = os.path.join(src, name)
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dstname = os.path.join(dst, name)
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try:
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if os.path.islink(srcname):
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linkto = os.readlink(srcname)
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if symlinks:
|
|
# We can't just leave it to `copy_function` because legacy
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# code with a custom `copy_function` may rely on copytree
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# doing the right thing.
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os.symlink(linkto, dstname)
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copystat(srcname, dstname, follow_symlinks=not symlinks)
|
|
else:
|
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# ignore dangling symlink if the flag is on
|
|
if not os.path.exists(linkto) and ignore_dangling_symlinks:
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continue
|
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# otherwise let the copy occurs. copy2 will raise an error
|
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if os.path.isdir(srcname):
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copytree(srcname, dstname, symlinks, ignore,
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copy_function)
|
|
else:
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copy_function(srcname, dstname)
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elif os.path.isdir(srcname):
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copytree(srcname, dstname, symlinks, ignore, copy_function)
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else:
|
|
# Will raise a SpecialFileError for unsupported file types
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copy_function(srcname, dstname)
|
|
# catch the Error from the recursive copytree so that we can
|
|
# continue with other files
|
|
except Error as err:
|
|
errors.extend(err.args[0])
|
|
except OSError as why:
|
|
errors.append((srcname, dstname, str(why)))
|
|
try:
|
|
copystat(src, dst)
|
|
except OSError as why:
|
|
# Copying file access times may fail on Windows
|
|
if getattr(why, 'winerror', None) is None:
|
|
errors.append((src, dst, str(why)))
|
|
if errors:
|
|
raise Error(errors)
|
|
return dst
|
|
|
|
# version vulnerable to race conditions
|
|
def _rmtree_unsafe(path, onerror):
|
|
try:
|
|
with os.scandir(path) as scandir_it:
|
|
entries = list(scandir_it)
|
|
except OSError:
|
|
onerror(os.scandir, path, sys.exc_info())
|
|
entries = []
|
|
for entry in entries:
|
|
fullname = entry.path
|
|
try:
|
|
is_dir = entry.is_dir(follow_symlinks=False)
|
|
except OSError:
|
|
is_dir = False
|
|
if is_dir:
|
|
try:
|
|
if entry.is_symlink():
|
|
# This can only happen if someone replaces
|
|
# a directory with a symlink after the call to
|
|
# os.scandir or entry.is_dir above.
|
|
raise OSError("Cannot call rmtree on a symbolic link")
|
|
except OSError:
|
|
onerror(os.path.islink, fullname, sys.exc_info())
|
|
continue
|
|
_rmtree_unsafe(fullname, onerror)
|
|
else:
|
|
try:
|
|
os.unlink(fullname)
|
|
except OSError:
|
|
onerror(os.unlink, fullname, sys.exc_info())
|
|
try:
|
|
os.rmdir(path)
|
|
except OSError:
|
|
onerror(os.rmdir, path, sys.exc_info())
|
|
|
|
# Version using fd-based APIs to protect against races
|
|
def _rmtree_safe_fd(topfd, path, onerror):
|
|
try:
|
|
with os.scandir(topfd) as scandir_it:
|
|
entries = list(scandir_it)
|
|
except OSError as err:
|
|
err.filename = path
|
|
onerror(os.scandir, path, sys.exc_info())
|
|
return
|
|
for entry in entries:
|
|
fullname = os.path.join(path, entry.name)
|
|
try:
|
|
is_dir = entry.is_dir(follow_symlinks=False)
|
|
if is_dir:
|
|
orig_st = entry.stat(follow_symlinks=False)
|
|
is_dir = stat.S_ISDIR(orig_st.st_mode)
|
|
except OSError:
|
|
is_dir = False
|
|
if is_dir:
|
|
try:
|
|
dirfd = os.open(entry.name, os.O_RDONLY, dir_fd=topfd)
|
|
except OSError:
|
|
onerror(os.open, fullname, sys.exc_info())
|
|
else:
|
|
try:
|
|
if os.path.samestat(orig_st, os.fstat(dirfd)):
|
|
_rmtree_safe_fd(dirfd, fullname, onerror)
|
|
try:
|
|
os.rmdir(entry.name, dir_fd=topfd)
|
|
except OSError:
|
|
onerror(os.rmdir, fullname, sys.exc_info())
|
|
else:
|
|
try:
|
|
# This can only happen if someone replaces
|
|
# a directory with a symlink after the call to
|
|
# os.scandir or stat.S_ISDIR above.
|
|
raise OSError("Cannot call rmtree on a symbolic "
|
|
"link")
|
|
except OSError:
|
|
onerror(os.path.islink, fullname, sys.exc_info())
|
|
finally:
|
|
os.close(dirfd)
|
|
else:
|
|
try:
|
|
os.unlink(entry.name, dir_fd=topfd)
|
|
except OSError:
|
|
onerror(os.unlink, fullname, sys.exc_info())
|
|
|
|
_use_fd_functions = ({os.open, os.stat, os.unlink, os.rmdir} <=
|
|
os.supports_dir_fd and
|
|
os.scandir in os.supports_fd and
|
|
os.stat in os.supports_follow_symlinks)
|
|
|
|
def rmtree(path, ignore_errors=False, onerror=None):
|
|
"""Recursively delete a directory tree.
|
|
|
|
If ignore_errors is set, errors are ignored; otherwise, if onerror
|
|
is set, it is called to handle the error with arguments (func,
|
|
path, exc_info) where func is platform and implementation dependent;
|
|
path is the argument to that function that caused it to fail; and
|
|
exc_info is a tuple returned by sys.exc_info(). If ignore_errors
|
|
is false and onerror is None, an exception is raised.
|
|
|
|
"""
|
|
if ignore_errors:
|
|
def onerror(*args):
|
|
pass
|
|
elif onerror is None:
|
|
def onerror(*args):
|
|
raise
|
|
if _use_fd_functions:
|
|
# While the unsafe rmtree works fine on bytes, the fd based does not.
|
|
if isinstance(path, bytes):
|
|
path = os.fsdecode(path)
|
|
# Note: To guard against symlink races, we use the standard
|
|
# lstat()/open()/fstat() trick.
|
|
try:
|
|
orig_st = os.lstat(path)
|
|
except Exception:
|
|
onerror(os.lstat, path, sys.exc_info())
|
|
return
|
|
try:
|
|
fd = os.open(path, os.O_RDONLY)
|
|
except Exception:
|
|
onerror(os.lstat, path, sys.exc_info())
|
|
return
|
|
try:
|
|
if os.path.samestat(orig_st, os.fstat(fd)):
|
|
_rmtree_safe_fd(fd, path, onerror)
|
|
try:
|
|
os.rmdir(path)
|
|
except OSError:
|
|
onerror(os.rmdir, path, sys.exc_info())
|
|
else:
|
|
try:
|
|
# symlinks to directories are forbidden, see bug #1669
|
|
raise OSError("Cannot call rmtree on a symbolic link")
|
|
except OSError:
|
|
onerror(os.path.islink, path, sys.exc_info())
|
|
finally:
|
|
os.close(fd)
|
|
else:
|
|
try:
|
|
if os.path.islink(path):
|
|
# symlinks to directories are forbidden, see bug #1669
|
|
raise OSError("Cannot call rmtree on a symbolic link")
|
|
except OSError:
|
|
onerror(os.path.islink, path, sys.exc_info())
|
|
# can't continue even if onerror hook returns
|
|
return
|
|
return _rmtree_unsafe(path, onerror)
|
|
|
|
# Allow introspection of whether or not the hardening against symlink
|
|
# attacks is supported on the current platform
|
|
rmtree.avoids_symlink_attacks = _use_fd_functions
|
|
|
|
def _basename(path):
|
|
# A basename() variant which first strips the trailing slash, if present.
|
|
# Thus we always get the last component of the path, even for directories.
|
|
sep = os.path.sep + (os.path.altsep or '')
|
|
return os.path.basename(path.rstrip(sep))
|
|
|
|
def move(src, dst, copy_function=copy2):
|
|
"""Recursively move a file or directory to another location. This is
|
|
similar to the Unix "mv" command. Return the file or directory's
|
|
destination.
|
|
|
|
If the destination is a directory or a symlink to a directory, the source
|
|
is moved inside the directory. The destination path must not already
|
|
exist.
|
|
|
|
If the destination already exists but is not a directory, it may be
|
|
overwritten depending on os.rename() semantics.
|
|
|
|
If the destination is on our current filesystem, then rename() is used.
|
|
Otherwise, src is copied to the destination and then removed. Symlinks are
|
|
recreated under the new name if os.rename() fails because of cross
|
|
filesystem renames.
|
|
|
|
The optional `copy_function` argument is a callable that will be used
|
|
to copy the source or it will be delegated to `copytree`.
|
|
By default, copy2() is used, but any function that supports the same
|
|
signature (like copy()) can be used.
|
|
|
|
A lot more could be done here... A look at a mv.c shows a lot of
|
|
the issues this implementation glosses over.
|
|
|
|
"""
|
|
real_dst = dst
|
|
if os.path.isdir(dst):
|
|
if _samefile(src, dst):
|
|
# We might be on a case insensitive filesystem,
|
|
# perform the rename anyway.
|
|
os.rename(src, dst)
|
|
return
|
|
|
|
real_dst = os.path.join(dst, _basename(src))
|
|
if os.path.exists(real_dst):
|
|
raise Error("Destination path '%s' already exists" % real_dst)
|
|
try:
|
|
os.rename(src, real_dst)
|
|
except OSError:
|
|
if os.path.islink(src):
|
|
linkto = os.readlink(src)
|
|
os.symlink(linkto, real_dst)
|
|
os.unlink(src)
|
|
elif os.path.isdir(src):
|
|
if _destinsrc(src, dst):
|
|
raise Error("Cannot move a directory '%s' into itself"
|
|
" '%s'." % (src, dst))
|
|
copytree(src, real_dst, copy_function=copy_function,
|
|
symlinks=True)
|
|
rmtree(src)
|
|
else:
|
|
copy_function(src, real_dst)
|
|
os.unlink(src)
|
|
return real_dst
|
|
|
|
def _destinsrc(src, dst):
|
|
src = os.path.abspath(src)
|
|
dst = os.path.abspath(dst)
|
|
if not src.endswith(os.path.sep):
|
|
src += os.path.sep
|
|
if not dst.endswith(os.path.sep):
|
|
dst += os.path.sep
|
|
return dst.startswith(src)
|
|
|
|
def _get_gid(name):
|
|
"""Returns a gid, given a group name."""
|
|
if getgrnam is None or name is None:
|
|
return None
|
|
try:
|
|
result = getgrnam(name)
|
|
except KeyError:
|
|
result = None
|
|
if result is not None:
|
|
return result[2]
|
|
return None
|
|
|
|
def _get_uid(name):
|
|
"""Returns an uid, given a user name."""
|
|
if getpwnam is None or name is None:
|
|
return None
|
|
try:
|
|
result = getpwnam(name)
|
|
except KeyError:
|
|
result = None
|
|
if result is not None:
|
|
return result[2]
|
|
return None
|
|
|
|
def _make_tarball(base_name, base_dir, compress="gzip", verbose=0, dry_run=0,
|
|
owner=None, group=None, logger=None):
|
|
"""Create a (possibly compressed) tar file from all the files under
|
|
'base_dir'.
|
|
|
|
'compress' must be "gzip" (the default), "bzip2", "xz", or None.
|
|
|
|
'owner' and 'group' can be used to define an owner and a group for the
|
|
archive that is being built. If not provided, the current owner and group
|
|
will be used.
|
|
|
|
The output tar file will be named 'base_name' + ".tar", possibly plus
|
|
the appropriate compression extension (".gz", ".bz2", or ".xz").
|
|
|
|
Returns the output filename.
|
|
"""
|
|
if compress is None:
|
|
tar_compression = ''
|
|
elif _ZLIB_SUPPORTED and compress == 'gzip':
|
|
tar_compression = 'gz'
|
|
elif _BZ2_SUPPORTED and compress == 'bzip2':
|
|
tar_compression = 'bz2'
|
|
elif _LZMA_SUPPORTED and compress == 'xz':
|
|
tar_compression = 'xz'
|
|
else:
|
|
raise ValueError("bad value for 'compress', or compression format not "
|
|
"supported : {0}".format(compress))
|
|
|
|
import tarfile # late import for breaking circular dependency
|
|
|
|
compress_ext = '.' + tar_compression if compress else ''
|
|
archive_name = base_name + '.tar' + compress_ext
|
|
archive_dir = os.path.dirname(archive_name)
|
|
|
|
if archive_dir and not os.path.exists(archive_dir):
|
|
if logger is not None:
|
|
logger.info("creating %s", archive_dir)
|
|
if not dry_run:
|
|
os.makedirs(archive_dir)
|
|
|
|
# creating the tarball
|
|
if logger is not None:
|
|
logger.info('Creating tar archive')
|
|
|
|
uid = _get_uid(owner)
|
|
gid = _get_gid(group)
|
|
|
|
def _set_uid_gid(tarinfo):
|
|
if gid is not None:
|
|
tarinfo.gid = gid
|
|
tarinfo.gname = group
|
|
if uid is not None:
|
|
tarinfo.uid = uid
|
|
tarinfo.uname = owner
|
|
return tarinfo
|
|
|
|
if not dry_run:
|
|
tar = tarfile.open(archive_name, 'w|%s' % tar_compression)
|
|
try:
|
|
tar.add(base_dir, filter=_set_uid_gid)
|
|
finally:
|
|
tar.close()
|
|
|
|
return archive_name
|
|
|
|
def _make_zipfile(base_name, base_dir, verbose=0, dry_run=0, logger=None):
|
|
"""Create a zip file from all the files under 'base_dir'.
|
|
|
|
The output zip file will be named 'base_name' + ".zip". Returns the
|
|
name of the output zip file.
|
|
"""
|
|
import zipfile # late import for breaking circular dependency
|
|
|
|
zip_filename = base_name + ".zip"
|
|
archive_dir = os.path.dirname(base_name)
|
|
|
|
if archive_dir and not os.path.exists(archive_dir):
|
|
if logger is not None:
|
|
logger.info("creating %s", archive_dir)
|
|
if not dry_run:
|
|
os.makedirs(archive_dir)
|
|
|
|
if logger is not None:
|
|
logger.info("creating '%s' and adding '%s' to it",
|
|
zip_filename, base_dir)
|
|
|
|
if not dry_run:
|
|
with zipfile.ZipFile(zip_filename, "w",
|
|
compression=zipfile.ZIP_DEFLATED) as zf:
|
|
path = os.path.normpath(base_dir)
|
|
if path != os.curdir:
|
|
zf.write(path, path)
|
|
if logger is not None:
|
|
logger.info("adding '%s'", path)
|
|
for dirpath, dirnames, filenames in os.walk(base_dir):
|
|
for name in sorted(dirnames):
|
|
path = os.path.normpath(os.path.join(dirpath, name))
|
|
zf.write(path, path)
|
|
if logger is not None:
|
|
logger.info("adding '%s'", path)
|
|
for name in filenames:
|
|
path = os.path.normpath(os.path.join(dirpath, name))
|
|
if os.path.isfile(path):
|
|
zf.write(path, path)
|
|
if logger is not None:
|
|
logger.info("adding '%s'", path)
|
|
|
|
return zip_filename
|
|
|
|
_ARCHIVE_FORMATS = {
|
|
'tar': (_make_tarball, [('compress', None)], "uncompressed tar file"),
|
|
}
|
|
|
|
if _ZLIB_SUPPORTED:
|
|
_ARCHIVE_FORMATS['gztar'] = (_make_tarball, [('compress', 'gzip')],
|
|
"gzip'ed tar-file")
|
|
_ARCHIVE_FORMATS['zip'] = (_make_zipfile, [], "ZIP file")
|
|
|
|
if _BZ2_SUPPORTED:
|
|
_ARCHIVE_FORMATS['bztar'] = (_make_tarball, [('compress', 'bzip2')],
|
|
"bzip2'ed tar-file")
|
|
|
|
if _LZMA_SUPPORTED:
|
|
_ARCHIVE_FORMATS['xztar'] = (_make_tarball, [('compress', 'xz')],
|
|
"xz'ed tar-file")
|
|
|
|
def get_archive_formats():
|
|
"""Returns a list of supported formats for archiving and unarchiving.
|
|
|
|
Each element of the returned sequence is a tuple (name, description)
|
|
"""
|
|
formats = [(name, registry[2]) for name, registry in
|
|
_ARCHIVE_FORMATS.items()]
|
|
formats.sort()
|
|
return formats
|
|
|
|
def register_archive_format(name, function, extra_args=None, description=''):
|
|
"""Registers an archive format.
|
|
|
|
name is the name of the format. function is the callable that will be
|
|
used to create archives. If provided, extra_args is a sequence of
|
|
(name, value) tuples that will be passed as arguments to the callable.
|
|
description can be provided to describe the format, and will be returned
|
|
by the get_archive_formats() function.
|
|
"""
|
|
if extra_args is None:
|
|
extra_args = []
|
|
if not callable(function):
|
|
raise TypeError('The %s object is not callable' % function)
|
|
if not isinstance(extra_args, (tuple, list)):
|
|
raise TypeError('extra_args needs to be a sequence')
|
|
for element in extra_args:
|
|
if not isinstance(element, (tuple, list)) or len(element) !=2:
|
|
raise TypeError('extra_args elements are : (arg_name, value)')
|
|
|
|
_ARCHIVE_FORMATS[name] = (function, extra_args, description)
|
|
|
|
def unregister_archive_format(name):
|
|
del _ARCHIVE_FORMATS[name]
|
|
|
|
def make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0,
|
|
dry_run=0, owner=None, group=None, logger=None):
|
|
"""Create an archive file (eg. zip or tar).
|
|
|
|
'base_name' is the name of the file to create, minus any format-specific
|
|
extension; 'format' is the archive format: one of "zip", "tar", "gztar",
|
|
"bztar", or "xztar". Or any other registered format.
|
|
|
|
'root_dir' is a directory that will be the root directory of the
|
|
archive; ie. we typically chdir into 'root_dir' before creating the
|
|
archive. 'base_dir' is the directory where we start archiving from;
|
|
ie. 'base_dir' will be the common prefix of all files and
|
|
directories in the archive. 'root_dir' and 'base_dir' both default
|
|
to the current directory. Returns the name of the archive file.
|
|
|
|
'owner' and 'group' are used when creating a tar archive. By default,
|
|
uses the current owner and group.
|
|
"""
|
|
save_cwd = os.getcwd()
|
|
if root_dir is not None:
|
|
if logger is not None:
|
|
logger.debug("changing into '%s'", root_dir)
|
|
base_name = os.path.abspath(base_name)
|
|
if not dry_run:
|
|
os.chdir(root_dir)
|
|
|
|
if base_dir is None:
|
|
base_dir = os.curdir
|
|
|
|
kwargs = {'dry_run': dry_run, 'logger': logger}
|
|
|
|
try:
|
|
format_info = _ARCHIVE_FORMATS[format]
|
|
except KeyError:
|
|
raise ValueError("unknown archive format '%s'" % format) from None
|
|
|
|
func = format_info[0]
|
|
for arg, val in format_info[1]:
|
|
kwargs[arg] = val
|
|
|
|
if format != 'zip':
|
|
kwargs['owner'] = owner
|
|
kwargs['group'] = group
|
|
|
|
try:
|
|
filename = func(base_name, base_dir, **kwargs)
|
|
finally:
|
|
if root_dir is not None:
|
|
if logger is not None:
|
|
logger.debug("changing back to '%s'", save_cwd)
|
|
os.chdir(save_cwd)
|
|
|
|
return filename
|
|
|
|
|
|
def get_unpack_formats():
|
|
"""Returns a list of supported formats for unpacking.
|
|
|
|
Each element of the returned sequence is a tuple
|
|
(name, extensions, description)
|
|
"""
|
|
formats = [(name, info[0], info[3]) for name, info in
|
|
_UNPACK_FORMATS.items()]
|
|
formats.sort()
|
|
return formats
|
|
|
|
def _check_unpack_options(extensions, function, extra_args):
|
|
"""Checks what gets registered as an unpacker."""
|
|
# first make sure no other unpacker is registered for this extension
|
|
existing_extensions = {}
|
|
for name, info in _UNPACK_FORMATS.items():
|
|
for ext in info[0]:
|
|
existing_extensions[ext] = name
|
|
|
|
for extension in extensions:
|
|
if extension in existing_extensions:
|
|
msg = '%s is already registered for "%s"'
|
|
raise RegistryError(msg % (extension,
|
|
existing_extensions[extension]))
|
|
|
|
if not callable(function):
|
|
raise TypeError('The registered function must be a callable')
|
|
|
|
|
|
def register_unpack_format(name, extensions, function, extra_args=None,
|
|
description=''):
|
|
"""Registers an unpack format.
|
|
|
|
`name` is the name of the format. `extensions` is a list of extensions
|
|
corresponding to the format.
|
|
|
|
`function` is the callable that will be
|
|
used to unpack archives. The callable will receive archives to unpack.
|
|
If it's unable to handle an archive, it needs to raise a ReadError
|
|
exception.
|
|
|
|
If provided, `extra_args` is a sequence of
|
|
(name, value) tuples that will be passed as arguments to the callable.
|
|
description can be provided to describe the format, and will be returned
|
|
by the get_unpack_formats() function.
|
|
"""
|
|
if extra_args is None:
|
|
extra_args = []
|
|
_check_unpack_options(extensions, function, extra_args)
|
|
_UNPACK_FORMATS[name] = extensions, function, extra_args, description
|
|
|
|
def unregister_unpack_format(name):
|
|
"""Removes the pack format from the registry."""
|
|
del _UNPACK_FORMATS[name]
|
|
|
|
def _ensure_directory(path):
|
|
"""Ensure that the parent directory of `path` exists"""
|
|
dirname = os.path.dirname(path)
|
|
if not os.path.isdir(dirname):
|
|
os.makedirs(dirname)
|
|
|
|
def _unpack_zipfile(filename, extract_dir):
|
|
"""Unpack zip `filename` to `extract_dir`
|
|
"""
|
|
import zipfile # late import for breaking circular dependency
|
|
|
|
if not zipfile.is_zipfile(filename):
|
|
raise ReadError("%s is not a zip file" % filename)
|
|
|
|
zip = zipfile.ZipFile(filename)
|
|
try:
|
|
for info in zip.infolist():
|
|
name = info.filename
|
|
|
|
# don't extract absolute paths or ones with .. in them
|
|
if name.startswith('/') or '..' in name:
|
|
continue
|
|
|
|
target = os.path.join(extract_dir, *name.split('/'))
|
|
if not target:
|
|
continue
|
|
|
|
_ensure_directory(target)
|
|
if not name.endswith('/'):
|
|
# file
|
|
data = zip.read(info.filename)
|
|
f = open(target, 'wb')
|
|
try:
|
|
f.write(data)
|
|
finally:
|
|
f.close()
|
|
del data
|
|
finally:
|
|
zip.close()
|
|
|
|
def _unpack_tarfile(filename, extract_dir):
|
|
"""Unpack tar/tar.gz/tar.bz2/tar.xz `filename` to `extract_dir`
|
|
"""
|
|
import tarfile # late import for breaking circular dependency
|
|
try:
|
|
tarobj = tarfile.open(filename)
|
|
except tarfile.TarError:
|
|
raise ReadError(
|
|
"%s is not a compressed or uncompressed tar file" % filename)
|
|
try:
|
|
tarobj.extractall(extract_dir)
|
|
finally:
|
|
tarobj.close()
|
|
|
|
_UNPACK_FORMATS = {
|
|
'tar': (['.tar'], _unpack_tarfile, [], "uncompressed tar file"),
|
|
'zip': (['.zip'], _unpack_zipfile, [], "ZIP file"),
|
|
}
|
|
|
|
if _ZLIB_SUPPORTED:
|
|
_UNPACK_FORMATS['gztar'] = (['.tar.gz', '.tgz'], _unpack_tarfile, [],
|
|
"gzip'ed tar-file")
|
|
|
|
if _BZ2_SUPPORTED:
|
|
_UNPACK_FORMATS['bztar'] = (['.tar.bz2', '.tbz2'], _unpack_tarfile, [],
|
|
"bzip2'ed tar-file")
|
|
|
|
if _LZMA_SUPPORTED:
|
|
_UNPACK_FORMATS['xztar'] = (['.tar.xz', '.txz'], _unpack_tarfile, [],
|
|
"xz'ed tar-file")
|
|
|
|
def _find_unpack_format(filename):
|
|
for name, info in _UNPACK_FORMATS.items():
|
|
for extension in info[0]:
|
|
if filename.endswith(extension):
|
|
return name
|
|
return None
|
|
|
|
def unpack_archive(filename, extract_dir=None, format=None):
|
|
"""Unpack an archive.
|
|
|
|
`filename` is the name of the archive.
|
|
|
|
`extract_dir` is the name of the target directory, where the archive
|
|
is unpacked. If not provided, the current working directory is used.
|
|
|
|
`format` is the archive format: one of "zip", "tar", "gztar", "bztar",
|
|
or "xztar". Or any other registered format. If not provided,
|
|
unpack_archive will use the filename extension and see if an unpacker
|
|
was registered for that extension.
|
|
|
|
In case none is found, a ValueError is raised.
|
|
"""
|
|
if extract_dir is None:
|
|
extract_dir = os.getcwd()
|
|
|
|
extract_dir = os.fspath(extract_dir)
|
|
filename = os.fspath(filename)
|
|
|
|
if format is not None:
|
|
try:
|
|
format_info = _UNPACK_FORMATS[format]
|
|
except KeyError:
|
|
raise ValueError("Unknown unpack format '{0}'".format(format)) from None
|
|
|
|
func = format_info[1]
|
|
func(filename, extract_dir, **dict(format_info[2]))
|
|
else:
|
|
# we need to look at the registered unpackers supported extensions
|
|
format = _find_unpack_format(filename)
|
|
if format is None:
|
|
raise ReadError("Unknown archive format '{0}'".format(filename))
|
|
|
|
func = _UNPACK_FORMATS[format][1]
|
|
kwargs = dict(_UNPACK_FORMATS[format][2])
|
|
func(filename, extract_dir, **kwargs)
|
|
|
|
|
|
if hasattr(os, 'statvfs'):
|
|
|
|
__all__.append('disk_usage')
|
|
_ntuple_diskusage = collections.namedtuple('usage', 'total used free')
|
|
_ntuple_diskusage.total.__doc__ = 'Total space in bytes'
|
|
_ntuple_diskusage.used.__doc__ = 'Used space in bytes'
|
|
_ntuple_diskusage.free.__doc__ = 'Free space in bytes'
|
|
|
|
def disk_usage(path):
|
|
"""Return disk usage statistics about the given path.
|
|
|
|
Returned value is a named tuple with attributes 'total', 'used' and
|
|
'free', which are the amount of total, used and free space, in bytes.
|
|
"""
|
|
st = os.statvfs(path)
|
|
free = st.f_bavail * st.f_frsize
|
|
total = st.f_blocks * st.f_frsize
|
|
used = (st.f_blocks - st.f_bfree) * st.f_frsize
|
|
return _ntuple_diskusage(total, used, free)
|
|
|
|
elif _WINDOWS:
|
|
|
|
__all__.append('disk_usage')
|
|
_ntuple_diskusage = collections.namedtuple('usage', 'total used free')
|
|
|
|
def disk_usage(path):
|
|
"""Return disk usage statistics about the given path.
|
|
|
|
Returned values is a named tuple with attributes 'total', 'used' and
|
|
'free', which are the amount of total, used and free space, in bytes.
|
|
"""
|
|
total, free = nt._getdiskusage(path)
|
|
used = total - free
|
|
return _ntuple_diskusage(total, used, free)
|
|
|
|
|
|
def chown(path, user=None, group=None):
|
|
"""Change owner user and group of the given path.
|
|
|
|
user and group can be the uid/gid or the user/group names, and in that case,
|
|
they are converted to their respective uid/gid.
|
|
"""
|
|
|
|
if user is None and group is None:
|
|
raise ValueError("user and/or group must be set")
|
|
|
|
_user = user
|
|
_group = group
|
|
|
|
# -1 means don't change it
|
|
if user is None:
|
|
_user = -1
|
|
# user can either be an int (the uid) or a string (the system username)
|
|
elif isinstance(user, str):
|
|
_user = _get_uid(user)
|
|
if _user is None:
|
|
raise LookupError("no such user: {!r}".format(user))
|
|
|
|
if group is None:
|
|
_group = -1
|
|
elif not isinstance(group, int):
|
|
_group = _get_gid(group)
|
|
if _group is None:
|
|
raise LookupError("no such group: {!r}".format(group))
|
|
|
|
os.chown(path, _user, _group)
|
|
|
|
def get_terminal_size(fallback=(80, 24)):
|
|
"""Get the size of the terminal window.
|
|
|
|
For each of the two dimensions, the environment variable, COLUMNS
|
|
and LINES respectively, is checked. If the variable is defined and
|
|
the value is a positive integer, it is used.
|
|
|
|
When COLUMNS or LINES is not defined, which is the common case,
|
|
the terminal connected to sys.__stdout__ is queried
|
|
by invoking os.get_terminal_size.
|
|
|
|
If the terminal size cannot be successfully queried, either because
|
|
the system doesn't support querying, or because we are not
|
|
connected to a terminal, the value given in fallback parameter
|
|
is used. Fallback defaults to (80, 24) which is the default
|
|
size used by many terminal emulators.
|
|
|
|
The value returned is a named tuple of type os.terminal_size.
|
|
"""
|
|
# columns, lines are the working values
|
|
try:
|
|
columns = int(os.environ['COLUMNS'])
|
|
except (KeyError, ValueError):
|
|
columns = 0
|
|
|
|
try:
|
|
lines = int(os.environ['LINES'])
|
|
except (KeyError, ValueError):
|
|
lines = 0
|
|
|
|
# only query if necessary
|
|
if columns <= 0 or lines <= 0:
|
|
try:
|
|
size = os.get_terminal_size(sys.__stdout__.fileno())
|
|
except (AttributeError, ValueError, OSError):
|
|
# stdout is None, closed, detached, or not a terminal, or
|
|
# os.get_terminal_size() is unsupported
|
|
size = os.terminal_size(fallback)
|
|
if columns <= 0:
|
|
columns = size.columns
|
|
if lines <= 0:
|
|
lines = size.lines
|
|
|
|
return os.terminal_size((columns, lines))
|
|
|
|
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.
|
|
|
|
"""
|
|
# Check that a given file can be accessed with the correct mode.
|
|
# Additionally check that `file` is not a directory, as on Windows
|
|
# directories pass the os.access check.
|
|
def _access_check(fn, mode):
|
|
return (os.path.exists(fn) and os.access(fn, mode)
|
|
and not os.path.isdir(fn))
|
|
|
|
# If we're given a path with a directory part, look it up directly rather
|
|
# than referring to PATH directories. This includes checking relative to the
|
|
# current directory, e.g. ./script
|
|
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":
|
|
# The current directory takes precedence on Windows.
|
|
if not os.curdir in path:
|
|
path.insert(0, os.curdir)
|
|
|
|
# PATHEXT is necessary to check on Windows.
|
|
pathext = os.environ.get("PATHEXT", "").split(os.pathsep)
|
|
# See if the given file matches any of the expected path extensions.
|
|
# This will allow us to short circuit when given "python.exe".
|
|
# If it does match, only test that one, otherwise we have to try
|
|
# others.
|
|
if any(cmd.lower().endswith(ext.lower()) for ext in pathext):
|
|
files = [cmd]
|
|
else:
|
|
files = [cmd + ext for ext in pathext]
|
|
else:
|
|
# On other platforms you don't have things like PATHEXT to tell you
|
|
# what file suffixes are executable, so just pass on cmd as-is.
|
|
files = [cmd]
|
|
|
|
seen = set()
|
|
for dir in path:
|
|
normdir = os.path.normcase(dir)
|
|
if not normdir in seen:
|
|
seen.add(normdir)
|
|
for thefile in files:
|
|
name = os.path.join(dir, thefile)
|
|
if _access_check(name, mode):
|
|
return name
|
|
return None
|