1039 lines
35 KiB
Python
1039 lines
35 KiB
Python
r"""OS routines for NT or Posix depending on what system we're on.
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This exports:
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- all functions from posix, nt or ce, e.g. unlink, stat, etc.
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- os.path is either posixpath or ntpath
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- os.name is either 'posix', 'nt' or 'ce'.
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- os.curdir is a string representing the current directory ('.' or ':')
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- os.pardir is a string representing the parent directory ('..' or '::')
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- os.sep is the (or a most common) pathname separator ('/' or ':' or '\\')
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- os.extsep is the extension separator (always '.')
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- os.altsep is the alternate pathname separator (None or '/')
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- os.pathsep is the component separator used in $PATH etc
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- os.linesep is the line separator in text files ('\r' or '\n' or '\r\n')
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- os.defpath is the default search path for executables
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- os.devnull is the file path of the null device ('/dev/null', etc.)
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Programs that import and use 'os' stand a better chance of being
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portable between different platforms. Of course, they must then
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only use functions that are defined by all platforms (e.g., unlink
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and opendir), and leave all pathname manipulation to os.path
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(e.g., split and join).
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"""
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#'
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import sys, errno
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import stat as st
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_names = sys.builtin_module_names
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# Note: more names are added to __all__ later.
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__all__ = ["altsep", "curdir", "pardir", "sep", "pathsep", "linesep",
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"defpath", "name", "path", "devnull", "SEEK_SET", "SEEK_CUR",
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"SEEK_END", "fsencode", "fsdecode", "get_exec_path", "fdopen",
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"popen", "extsep"]
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def _exists(name):
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return name in globals()
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def _get_exports_list(module):
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try:
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return list(module.__all__)
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except AttributeError:
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return [n for n in dir(module) if n[0] != '_']
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# Any new dependencies of the os module and/or changes in path separator
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# requires updating importlib as well.
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if 'posix' in _names:
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name = 'posix'
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linesep = '\n'
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from posix import *
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try:
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from posix import _exit
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__all__.append('_exit')
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except ImportError:
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pass
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import posixpath as path
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try:
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from posix import _have_functions
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except ImportError:
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pass
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import posix
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__all__.extend(_get_exports_list(posix))
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del posix
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elif 'nt' in _names:
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name = 'nt'
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linesep = '\r\n'
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from nt import *
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try:
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from nt import _exit
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__all__.append('_exit')
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except ImportError:
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pass
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import ntpath as path
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import nt
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__all__.extend(_get_exports_list(nt))
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del nt
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try:
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from nt import _have_functions
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except ImportError:
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pass
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elif 'ce' in _names:
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name = 'ce'
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linesep = '\r\n'
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from ce import *
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try:
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from ce import _exit
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__all__.append('_exit')
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except ImportError:
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pass
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# We can use the standard Windows path.
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import ntpath as path
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import ce
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__all__.extend(_get_exports_list(ce))
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del ce
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try:
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from ce import _have_functions
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except ImportError:
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pass
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else:
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raise ImportError('no os specific module found')
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sys.modules['os.path'] = path
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from os.path import (curdir, pardir, sep, pathsep, defpath, extsep, altsep,
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devnull)
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del _names
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if _exists("_have_functions"):
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_globals = globals()
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def _add(str, fn):
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if (fn in _globals) and (str in _have_functions):
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_set.add(_globals[fn])
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_set = set()
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_add("HAVE_FACCESSAT", "access")
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_add("HAVE_FCHMODAT", "chmod")
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_add("HAVE_FCHOWNAT", "chown")
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_add("HAVE_FSTATAT", "stat")
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_add("HAVE_FUTIMESAT", "utime")
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_add("HAVE_LINKAT", "link")
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_add("HAVE_MKDIRAT", "mkdir")
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_add("HAVE_MKFIFOAT", "mkfifo")
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_add("HAVE_MKNODAT", "mknod")
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_add("HAVE_OPENAT", "open")
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_add("HAVE_READLINKAT", "readlink")
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_add("HAVE_RENAMEAT", "rename")
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_add("HAVE_SYMLINKAT", "symlink")
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_add("HAVE_UNLINKAT", "unlink")
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_add("HAVE_UNLINKAT", "rmdir")
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_add("HAVE_UTIMENSAT", "utime")
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supports_dir_fd = _set
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_set = set()
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_add("HAVE_FACCESSAT", "access")
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supports_effective_ids = _set
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_set = set()
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_add("HAVE_FCHDIR", "chdir")
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_add("HAVE_FCHMOD", "chmod")
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_add("HAVE_FCHOWN", "chown")
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_add("HAVE_FDOPENDIR", "listdir")
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_add("HAVE_FEXECVE", "execve")
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_set.add(stat) # fstat always works
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_add("HAVE_FTRUNCATE", "truncate")
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_add("HAVE_FUTIMENS", "utime")
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_add("HAVE_FUTIMES", "utime")
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_add("HAVE_FPATHCONF", "pathconf")
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if _exists("statvfs") and _exists("fstatvfs"): # mac os x10.3
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_add("HAVE_FSTATVFS", "statvfs")
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supports_fd = _set
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_set = set()
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_add("HAVE_FACCESSAT", "access")
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# Some platforms don't support lchmod(). Often the function exists
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# anyway, as a stub that always returns ENOSUP or perhaps EOPNOTSUPP.
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# (No, I don't know why that's a good design.) ./configure will detect
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# this and reject it--so HAVE_LCHMOD still won't be defined on such
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# platforms. This is Very Helpful.
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#
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# However, sometimes platforms without a working lchmod() *do* have
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# fchmodat(). (Examples: Linux kernel 3.2 with glibc 2.15,
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# OpenIndiana 3.x.) And fchmodat() has a flag that theoretically makes
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# it behave like lchmod(). So in theory it would be a suitable
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# replacement for lchmod(). But when lchmod() doesn't work, fchmodat()'s
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# flag doesn't work *either*. Sadly ./configure isn't sophisticated
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# enough to detect this condition--it only determines whether or not
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# fchmodat() minimally works.
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#
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# Therefore we simply ignore fchmodat() when deciding whether or not
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# os.chmod supports follow_symlinks. Just checking lchmod() is
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# sufficient. After all--if you have a working fchmodat(), your
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# lchmod() almost certainly works too.
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#
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# _add("HAVE_FCHMODAT", "chmod")
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_add("HAVE_FCHOWNAT", "chown")
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_add("HAVE_FSTATAT", "stat")
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_add("HAVE_LCHFLAGS", "chflags")
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_add("HAVE_LCHMOD", "chmod")
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if _exists("lchown"): # mac os x10.3
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_add("HAVE_LCHOWN", "chown")
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_add("HAVE_LINKAT", "link")
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_add("HAVE_LUTIMES", "utime")
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_add("HAVE_LSTAT", "stat")
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_add("HAVE_FSTATAT", "stat")
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_add("HAVE_UTIMENSAT", "utime")
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_add("MS_WINDOWS", "stat")
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supports_follow_symlinks = _set
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del _set
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del _have_functions
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del _globals
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del _add
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# Python uses fixed values for the SEEK_ constants; they are mapped
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# to native constants if necessary in posixmodule.c
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# Other possible SEEK values are directly imported from posixmodule.c
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SEEK_SET = 0
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SEEK_CUR = 1
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SEEK_END = 2
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# Super directory utilities.
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# (Inspired by Eric Raymond; the doc strings are mostly his)
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def makedirs(name, mode=0o777, exist_ok=False):
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"""makedirs(name [, mode=0o777][, exist_ok=False])
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Super-mkdir; create a leaf directory and all intermediate ones. Works like
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mkdir, except that any intermediate path segment (not just the rightmost)
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will be created if it does not exist. If the target directory already
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exists, raise an OSError if exist_ok is False. Otherwise no exception is
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raised. This is recursive.
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"""
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head, tail = path.split(name)
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if not tail:
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head, tail = path.split(head)
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if head and tail and not path.exists(head):
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try:
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makedirs(head, mode, exist_ok)
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except FileExistsError:
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# Defeats race condition when another thread created the path
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pass
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cdir = curdir
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if isinstance(tail, bytes):
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cdir = bytes(curdir, 'ASCII')
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if tail == cdir: # xxx/newdir/. exists if xxx/newdir exists
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return
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try:
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mkdir(name, mode)
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except OSError:
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# Cannot rely on checking for EEXIST, since the operating system
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# could give priority to other errors like EACCES or EROFS
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if not exist_ok or not path.isdir(name):
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raise
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def removedirs(name):
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"""removedirs(name)
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Super-rmdir; remove a leaf directory and all empty intermediate
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ones. Works like rmdir except that, if the leaf directory is
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successfully removed, directories corresponding to rightmost path
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segments will be pruned away until either the whole path is
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consumed or an error occurs. Errors during this latter phase are
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ignored -- they generally mean that a directory was not empty.
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"""
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rmdir(name)
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head, tail = path.split(name)
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if not tail:
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head, tail = path.split(head)
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while head and tail:
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try:
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rmdir(head)
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except OSError:
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break
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head, tail = path.split(head)
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def renames(old, new):
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"""renames(old, new)
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Super-rename; create directories as necessary and delete any left
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empty. Works like rename, except creation of any intermediate
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directories needed to make the new pathname good is attempted
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first. After the rename, directories corresponding to rightmost
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path segments of the old name will be pruned until either the
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whole path is consumed or a nonempty directory is found.
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Note: this function can fail with the new directory structure made
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if you lack permissions needed to unlink the leaf directory or
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file.
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"""
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head, tail = path.split(new)
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if head and tail and not path.exists(head):
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makedirs(head)
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rename(old, new)
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head, tail = path.split(old)
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if head and tail:
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try:
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removedirs(head)
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except OSError:
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pass
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__all__.extend(["makedirs", "removedirs", "renames"])
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def walk(top, topdown=True, onerror=None, followlinks=False):
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"""Directory tree generator.
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For each directory in the directory tree rooted at top (including top
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itself, but excluding '.' and '..'), yields a 3-tuple
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dirpath, dirnames, filenames
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dirpath is a string, the path to the directory. dirnames is a list of
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the names of the subdirectories in dirpath (excluding '.' and '..').
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filenames is a list of the names of the non-directory files in dirpath.
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Note that the names in the lists are just names, with no path components.
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To get a full path (which begins with top) to a file or directory in
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dirpath, do os.path.join(dirpath, name).
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If optional arg 'topdown' is true or not specified, the triple for a
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directory is generated before the triples for any of its subdirectories
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(directories are generated top down). If topdown is false, the triple
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for a directory is generated after the triples for all of its
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subdirectories (directories are generated bottom up).
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When topdown is true, the caller can modify the dirnames list in-place
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(e.g., via del or slice assignment), and walk will only recurse into the
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subdirectories whose names remain in dirnames; this can be used to prune the
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search, or to impose a specific order of visiting. Modifying dirnames when
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topdown is false is ineffective, since the directories in dirnames have
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already been generated by the time dirnames itself is generated. No matter
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the value of topdown, the list of subdirectories is retrieved before the
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tuples for the directory and its subdirectories are generated.
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By default errors from the os.scandir() call are ignored. If
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optional arg 'onerror' is specified, it should be a function; it
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will be called with one argument, an OSError instance. It can
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report the error to continue with the walk, or raise the exception
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to abort the walk. Note that the filename is available as the
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filename attribute of the exception object.
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By default, os.walk does not follow symbolic links to subdirectories on
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systems that support them. In order to get this functionality, set the
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optional argument 'followlinks' to true.
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Caution: if you pass a relative pathname for top, don't change the
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current working directory between resumptions of walk. walk never
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changes the current directory, and assumes that the client doesn't
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either.
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Example:
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import os
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from os.path import join, getsize
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for root, dirs, files in os.walk('python/Lib/email'):
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print(root, "consumes", end="")
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print(sum([getsize(join(root, name)) for name in files]), end="")
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print("bytes in", len(files), "non-directory files")
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if 'CVS' in dirs:
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dirs.remove('CVS') # don't visit CVS directories
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"""
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dirs = []
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nondirs = []
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# We may not have read permission for top, in which case we can't
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# get a list of the files the directory contains. os.walk
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# always suppressed the exception then, rather than blow up for a
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# minor reason when (say) a thousand readable directories are still
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# left to visit. That logic is copied here.
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try:
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if name == 'nt' and isinstance(top, bytes):
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scandir_it = _dummy_scandir(top)
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else:
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# Note that scandir is global in this module due
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# to earlier import-*.
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scandir_it = scandir(top)
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entries = list(scandir_it)
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except OSError as error:
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if onerror is not None:
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onerror(error)
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return
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for entry in entries:
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try:
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is_dir = entry.is_dir()
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except OSError:
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# If is_dir() raises an OSError, consider that the entry is not
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# a directory, same behaviour than os.path.isdir().
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is_dir = False
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if is_dir:
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dirs.append(entry.name)
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else:
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nondirs.append(entry.name)
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if not topdown and is_dir:
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# Bottom-up: recurse into sub-directory, but exclude symlinks to
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# directories if followlinks is False
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if followlinks:
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walk_into = True
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else:
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try:
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is_symlink = entry.is_symlink()
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except OSError:
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# If is_symlink() raises an OSError, consider that the
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# entry is not a symbolic link, same behaviour than
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# os.path.islink().
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is_symlink = False
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walk_into = not is_symlink
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if walk_into:
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yield from walk(entry.path, topdown, onerror, followlinks)
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# Yield before recursion if going top down
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if topdown:
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yield top, dirs, nondirs
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# Recurse into sub-directories
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islink, join = path.islink, path.join
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for dirname in dirs:
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new_path = join(top, dirname)
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# Issue #23605: os.path.islink() is used instead of caching
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# entry.is_symlink() result during the loop on os.scandir() because
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# the caller can replace the directory entry during the "yield"
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# above.
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if followlinks or not islink(new_path):
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yield from walk(new_path, topdown, onerror, followlinks)
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else:
|
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# Yield after recursion if going bottom up
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yield top, dirs, nondirs
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|
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class _DummyDirEntry:
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def __init__(self, dir, name):
|
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self.name = name
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self.path = path.join(dir, name)
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def is_dir(self):
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return path.isdir(self.path)
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def is_symlink(self):
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return path.islink(self.path)
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|
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def _dummy_scandir(dir):
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# listdir-based implementation for bytes patches on Windows
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for name in listdir(dir):
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yield _DummyDirEntry(dir, name)
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|
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__all__.append("walk")
|
|
|
|
if {open, stat} <= supports_dir_fd and {listdir, stat} <= supports_fd:
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|
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def fwalk(top=".", topdown=True, onerror=None, *, follow_symlinks=False, dir_fd=None):
|
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"""Directory tree generator.
|
|
|
|
This behaves exactly like walk(), except that it yields a 4-tuple
|
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dirpath, dirnames, filenames, dirfd
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|
|
`dirpath`, `dirnames` and `filenames` are identical to walk() output,
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|
and `dirfd` is a file descriptor referring to the directory `dirpath`.
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|
|
The advantage of fwalk() over walk() is that it's safe against symlink
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|
races (when follow_symlinks is False).
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|
|
If dir_fd is not None, it should be a file descriptor open to a directory,
|
|
and top should be relative; top will then be relative to that directory.
|
|
(dir_fd is always supported for fwalk.)
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|
|
Caution:
|
|
Since fwalk() yields file descriptors, those are only valid until the
|
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next iteration step, so you should dup() them if you want to keep them
|
|
for a longer period.
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|
|
|
Example:
|
|
|
|
import os
|
|
for root, dirs, files, rootfd in os.fwalk('python/Lib/email'):
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print(root, "consumes", end="")
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print(sum([os.stat(name, dir_fd=rootfd).st_size for name in files]),
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end="")
|
|
print("bytes in", len(files), "non-directory files")
|
|
if 'CVS' in dirs:
|
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dirs.remove('CVS') # don't visit CVS directories
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|
"""
|
|
# Note: To guard against symlink races, we use the standard
|
|
# lstat()/open()/fstat() trick.
|
|
orig_st = stat(top, follow_symlinks=False, dir_fd=dir_fd)
|
|
topfd = open(top, O_RDONLY, dir_fd=dir_fd)
|
|
try:
|
|
if (follow_symlinks or (st.S_ISDIR(orig_st.st_mode) and
|
|
path.samestat(orig_st, stat(topfd)))):
|
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yield from _fwalk(topfd, top, topdown, onerror, follow_symlinks)
|
|
finally:
|
|
close(topfd)
|
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|
|
def _fwalk(topfd, toppath, topdown, onerror, follow_symlinks):
|
|
# Note: This uses O(depth of the directory tree) file descriptors: if
|
|
# necessary, it can be adapted to only require O(1) FDs, see issue
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|
# #13734.
|
|
|
|
names = listdir(topfd)
|
|
dirs, nondirs = [], []
|
|
for name in names:
|
|
try:
|
|
# Here, we don't use AT_SYMLINK_NOFOLLOW to be consistent with
|
|
# walk() which reports symlinks to directories as directories.
|
|
# We do however check for symlinks before recursing into
|
|
# a subdirectory.
|
|
if st.S_ISDIR(stat(name, dir_fd=topfd).st_mode):
|
|
dirs.append(name)
|
|
else:
|
|
nondirs.append(name)
|
|
except FileNotFoundError:
|
|
try:
|
|
# Add dangling symlinks, ignore disappeared files
|
|
if st.S_ISLNK(stat(name, dir_fd=topfd, follow_symlinks=False)
|
|
.st_mode):
|
|
nondirs.append(name)
|
|
except FileNotFoundError:
|
|
continue
|
|
|
|
if topdown:
|
|
yield toppath, dirs, nondirs, topfd
|
|
|
|
for name in dirs:
|
|
try:
|
|
orig_st = stat(name, dir_fd=topfd, follow_symlinks=follow_symlinks)
|
|
dirfd = open(name, O_RDONLY, dir_fd=topfd)
|
|
except OSError as err:
|
|
if onerror is not None:
|
|
onerror(err)
|
|
continue
|
|
try:
|
|
if follow_symlinks or path.samestat(orig_st, stat(dirfd)):
|
|
dirpath = path.join(toppath, name)
|
|
yield from _fwalk(dirfd, dirpath, topdown, onerror, follow_symlinks)
|
|
finally:
|
|
close(dirfd)
|
|
|
|
if not topdown:
|
|
yield toppath, dirs, nondirs, topfd
|
|
|
|
__all__.append("fwalk")
|
|
|
|
# Make sure os.environ exists, at least
|
|
try:
|
|
environ
|
|
except NameError:
|
|
environ = {}
|
|
|
|
def execl(file, *args):
|
|
"""execl(file, *args)
|
|
|
|
Execute the executable file with argument list args, replacing the
|
|
current process. """
|
|
execv(file, args)
|
|
|
|
def execle(file, *args):
|
|
"""execle(file, *args, env)
|
|
|
|
Execute the executable file with argument list args and
|
|
environment env, replacing the current process. """
|
|
env = args[-1]
|
|
execve(file, args[:-1], env)
|
|
|
|
def execlp(file, *args):
|
|
"""execlp(file, *args)
|
|
|
|
Execute the executable file (which is searched for along $PATH)
|
|
with argument list args, replacing the current process. """
|
|
execvp(file, args)
|
|
|
|
def execlpe(file, *args):
|
|
"""execlpe(file, *args, env)
|
|
|
|
Execute the executable file (which is searched for along $PATH)
|
|
with argument list args and environment env, replacing the current
|
|
process. """
|
|
env = args[-1]
|
|
execvpe(file, args[:-1], env)
|
|
|
|
def execvp(file, args):
|
|
"""execvp(file, args)
|
|
|
|
Execute the executable file (which is searched for along $PATH)
|
|
with argument list args, replacing the current process.
|
|
args may be a list or tuple of strings. """
|
|
_execvpe(file, args)
|
|
|
|
def execvpe(file, args, env):
|
|
"""execvpe(file, args, env)
|
|
|
|
Execute the executable file (which is searched for along $PATH)
|
|
with argument list args and environment env , replacing the
|
|
current process.
|
|
args may be a list or tuple of strings. """
|
|
_execvpe(file, args, env)
|
|
|
|
__all__.extend(["execl","execle","execlp","execlpe","execvp","execvpe"])
|
|
|
|
def _execvpe(file, args, env=None):
|
|
if env is not None:
|
|
exec_func = execve
|
|
argrest = (args, env)
|
|
else:
|
|
exec_func = execv
|
|
argrest = (args,)
|
|
env = environ
|
|
|
|
head, tail = path.split(file)
|
|
if head:
|
|
exec_func(file, *argrest)
|
|
return
|
|
last_exc = saved_exc = None
|
|
saved_tb = None
|
|
path_list = get_exec_path(env)
|
|
if name != 'nt':
|
|
file = fsencode(file)
|
|
path_list = map(fsencode, path_list)
|
|
for dir in path_list:
|
|
fullname = path.join(dir, file)
|
|
try:
|
|
exec_func(fullname, *argrest)
|
|
except OSError as e:
|
|
last_exc = e
|
|
tb = sys.exc_info()[2]
|
|
if (e.errno != errno.ENOENT and e.errno != errno.ENOTDIR
|
|
and saved_exc is None):
|
|
saved_exc = e
|
|
saved_tb = tb
|
|
if saved_exc:
|
|
raise saved_exc.with_traceback(saved_tb)
|
|
raise last_exc.with_traceback(tb)
|
|
|
|
|
|
def get_exec_path(env=None):
|
|
"""Returns the sequence of directories that will be searched for the
|
|
named executable (similar to a shell) when launching a process.
|
|
|
|
*env* must be an environment variable dict or None. If *env* is None,
|
|
os.environ will be used.
|
|
"""
|
|
# Use a local import instead of a global import to limit the number of
|
|
# modules loaded at startup: the os module is always loaded at startup by
|
|
# Python. It may also avoid a bootstrap issue.
|
|
import warnings
|
|
|
|
if env is None:
|
|
env = environ
|
|
|
|
# {b'PATH': ...}.get('PATH') and {'PATH': ...}.get(b'PATH') emit a
|
|
# BytesWarning when using python -b or python -bb: ignore the warning
|
|
with warnings.catch_warnings():
|
|
warnings.simplefilter("ignore", BytesWarning)
|
|
|
|
try:
|
|
path_list = env.get('PATH')
|
|
except TypeError:
|
|
path_list = None
|
|
|
|
if supports_bytes_environ:
|
|
try:
|
|
path_listb = env[b'PATH']
|
|
except (KeyError, TypeError):
|
|
pass
|
|
else:
|
|
if path_list is not None:
|
|
raise ValueError(
|
|
"env cannot contain 'PATH' and b'PATH' keys")
|
|
path_list = path_listb
|
|
|
|
if path_list is not None and isinstance(path_list, bytes):
|
|
path_list = fsdecode(path_list)
|
|
|
|
if path_list is None:
|
|
path_list = defpath
|
|
return path_list.split(pathsep)
|
|
|
|
|
|
# Change environ to automatically call putenv(), unsetenv if they exist.
|
|
from _collections_abc import MutableMapping
|
|
|
|
class _Environ(MutableMapping):
|
|
def __init__(self, data, encodekey, decodekey, encodevalue, decodevalue, putenv, unsetenv):
|
|
self.encodekey = encodekey
|
|
self.decodekey = decodekey
|
|
self.encodevalue = encodevalue
|
|
self.decodevalue = decodevalue
|
|
self.putenv = putenv
|
|
self.unsetenv = unsetenv
|
|
self._data = data
|
|
|
|
def __getitem__(self, key):
|
|
try:
|
|
value = self._data[self.encodekey(key)]
|
|
except KeyError:
|
|
# raise KeyError with the original key value
|
|
raise KeyError(key) from None
|
|
return self.decodevalue(value)
|
|
|
|
def __setitem__(self, key, value):
|
|
key = self.encodekey(key)
|
|
value = self.encodevalue(value)
|
|
self.putenv(key, value)
|
|
self._data[key] = value
|
|
|
|
def __delitem__(self, key):
|
|
encodedkey = self.encodekey(key)
|
|
self.unsetenv(encodedkey)
|
|
try:
|
|
del self._data[encodedkey]
|
|
except KeyError:
|
|
# raise KeyError with the original key value
|
|
raise KeyError(key) from None
|
|
|
|
def __iter__(self):
|
|
for key in self._data:
|
|
yield self.decodekey(key)
|
|
|
|
def __len__(self):
|
|
return len(self._data)
|
|
|
|
def __repr__(self):
|
|
return 'environ({{{}}})'.format(', '.join(
|
|
('{!r}: {!r}'.format(self.decodekey(key), self.decodevalue(value))
|
|
for key, value in self._data.items())))
|
|
|
|
def copy(self):
|
|
return dict(self)
|
|
|
|
def setdefault(self, key, value):
|
|
if key not in self:
|
|
self[key] = value
|
|
return self[key]
|
|
|
|
try:
|
|
_putenv = putenv
|
|
except NameError:
|
|
_putenv = lambda key, value: None
|
|
else:
|
|
if "putenv" not in __all__:
|
|
__all__.append("putenv")
|
|
|
|
try:
|
|
_unsetenv = unsetenv
|
|
except NameError:
|
|
_unsetenv = lambda key: _putenv(key, "")
|
|
else:
|
|
if "unsetenv" not in __all__:
|
|
__all__.append("unsetenv")
|
|
|
|
def _createenviron():
|
|
if name == 'nt':
|
|
# Where Env Var Names Must Be UPPERCASE
|
|
def check_str(value):
|
|
if not isinstance(value, str):
|
|
raise TypeError("str expected, not %s" % type(value).__name__)
|
|
return value
|
|
encode = check_str
|
|
decode = str
|
|
def encodekey(key):
|
|
return encode(key).upper()
|
|
data = {}
|
|
for key, value in environ.items():
|
|
data[encodekey(key)] = value
|
|
else:
|
|
# Where Env Var Names Can Be Mixed Case
|
|
encoding = sys.getfilesystemencoding()
|
|
def encode(value):
|
|
if not isinstance(value, str):
|
|
raise TypeError("str expected, not %s" % type(value).__name__)
|
|
return value.encode(encoding, 'surrogateescape')
|
|
def decode(value):
|
|
return value.decode(encoding, 'surrogateescape')
|
|
encodekey = encode
|
|
data = environ
|
|
return _Environ(data,
|
|
encodekey, decode,
|
|
encode, decode,
|
|
_putenv, _unsetenv)
|
|
|
|
# unicode environ
|
|
environ = _createenviron()
|
|
del _createenviron
|
|
|
|
|
|
def getenv(key, default=None):
|
|
"""Get an environment variable, return None if it doesn't exist.
|
|
The optional second argument can specify an alternate default.
|
|
key, default and the result are str."""
|
|
return environ.get(key, default)
|
|
|
|
supports_bytes_environ = (name != 'nt')
|
|
__all__.extend(("getenv", "supports_bytes_environ"))
|
|
|
|
if supports_bytes_environ:
|
|
def _check_bytes(value):
|
|
if not isinstance(value, bytes):
|
|
raise TypeError("bytes expected, not %s" % type(value).__name__)
|
|
return value
|
|
|
|
# bytes environ
|
|
environb = _Environ(environ._data,
|
|
_check_bytes, bytes,
|
|
_check_bytes, bytes,
|
|
_putenv, _unsetenv)
|
|
del _check_bytes
|
|
|
|
def getenvb(key, default=None):
|
|
"""Get an environment variable, return None if it doesn't exist.
|
|
The optional second argument can specify an alternate default.
|
|
key, default and the result are bytes."""
|
|
return environb.get(key, default)
|
|
|
|
__all__.extend(("environb", "getenvb"))
|
|
|
|
def _fscodec():
|
|
encoding = sys.getfilesystemencoding()
|
|
if encoding == 'mbcs':
|
|
errors = 'strict'
|
|
else:
|
|
errors = 'surrogateescape'
|
|
|
|
def fsencode(filename):
|
|
"""
|
|
Encode filename to the filesystem encoding with 'surrogateescape' error
|
|
handler, return bytes unchanged. On Windows, use 'strict' error handler if
|
|
the file system encoding is 'mbcs' (which is the default encoding).
|
|
"""
|
|
if isinstance(filename, bytes):
|
|
return filename
|
|
elif isinstance(filename, str):
|
|
return filename.encode(encoding, errors)
|
|
else:
|
|
raise TypeError("expect bytes or str, not %s" % type(filename).__name__)
|
|
|
|
def fsdecode(filename):
|
|
"""
|
|
Decode filename from the filesystem encoding with 'surrogateescape' error
|
|
handler, return str unchanged. On Windows, use 'strict' error handler if
|
|
the file system encoding is 'mbcs' (which is the default encoding).
|
|
"""
|
|
if isinstance(filename, str):
|
|
return filename
|
|
elif isinstance(filename, bytes):
|
|
return filename.decode(encoding, errors)
|
|
else:
|
|
raise TypeError("expect bytes or str, not %s" % type(filename).__name__)
|
|
|
|
return fsencode, fsdecode
|
|
|
|
fsencode, fsdecode = _fscodec()
|
|
del _fscodec
|
|
|
|
# Supply spawn*() (probably only for Unix)
|
|
if _exists("fork") and not _exists("spawnv") and _exists("execv"):
|
|
|
|
P_WAIT = 0
|
|
P_NOWAIT = P_NOWAITO = 1
|
|
|
|
__all__.extend(["P_WAIT", "P_NOWAIT", "P_NOWAITO"])
|
|
|
|
# XXX Should we support P_DETACH? I suppose it could fork()**2
|
|
# and close the std I/O streams. Also, P_OVERLAY is the same
|
|
# as execv*()?
|
|
|
|
def _spawnvef(mode, file, args, env, func):
|
|
# Internal helper; func is the exec*() function to use
|
|
pid = fork()
|
|
if not pid:
|
|
# Child
|
|
try:
|
|
if env is None:
|
|
func(file, args)
|
|
else:
|
|
func(file, args, env)
|
|
except:
|
|
_exit(127)
|
|
else:
|
|
# Parent
|
|
if mode == P_NOWAIT:
|
|
return pid # Caller is responsible for waiting!
|
|
while 1:
|
|
wpid, sts = waitpid(pid, 0)
|
|
if WIFSTOPPED(sts):
|
|
continue
|
|
elif WIFSIGNALED(sts):
|
|
return -WTERMSIG(sts)
|
|
elif WIFEXITED(sts):
|
|
return WEXITSTATUS(sts)
|
|
else:
|
|
raise OSError("Not stopped, signaled or exited???")
|
|
|
|
def spawnv(mode, file, args):
|
|
"""spawnv(mode, file, args) -> integer
|
|
|
|
Execute file with arguments from args in a subprocess.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return _spawnvef(mode, file, args, None, execv)
|
|
|
|
def spawnve(mode, file, args, env):
|
|
"""spawnve(mode, file, args, env) -> integer
|
|
|
|
Execute file with arguments from args in a subprocess with the
|
|
specified environment.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return _spawnvef(mode, file, args, env, execve)
|
|
|
|
# Note: spawnvp[e] is't currently supported on Windows
|
|
|
|
def spawnvp(mode, file, args):
|
|
"""spawnvp(mode, file, args) -> integer
|
|
|
|
Execute file (which is looked for along $PATH) with arguments from
|
|
args in a subprocess.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return _spawnvef(mode, file, args, None, execvp)
|
|
|
|
def spawnvpe(mode, file, args, env):
|
|
"""spawnvpe(mode, file, args, env) -> integer
|
|
|
|
Execute file (which is looked for along $PATH) with arguments from
|
|
args in a subprocess with the supplied environment.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return _spawnvef(mode, file, args, env, execvpe)
|
|
|
|
|
|
__all__.extend(["spawnv", "spawnve", "spawnvp", "spawnvpe"])
|
|
|
|
|
|
if _exists("spawnv"):
|
|
# These aren't supplied by the basic Windows code
|
|
# but can be easily implemented in Python
|
|
|
|
def spawnl(mode, file, *args):
|
|
"""spawnl(mode, file, *args) -> integer
|
|
|
|
Execute file with arguments from args in a subprocess.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return spawnv(mode, file, args)
|
|
|
|
def spawnle(mode, file, *args):
|
|
"""spawnle(mode, file, *args, env) -> integer
|
|
|
|
Execute file with arguments from args in a subprocess with the
|
|
supplied environment.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
env = args[-1]
|
|
return spawnve(mode, file, args[:-1], env)
|
|
|
|
|
|
__all__.extend(["spawnl", "spawnle"])
|
|
|
|
|
|
if _exists("spawnvp"):
|
|
# At the moment, Windows doesn't implement spawnvp[e],
|
|
# so it won't have spawnlp[e] either.
|
|
def spawnlp(mode, file, *args):
|
|
"""spawnlp(mode, file, *args) -> integer
|
|
|
|
Execute file (which is looked for along $PATH) with arguments from
|
|
args in a subprocess with the supplied environment.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
return spawnvp(mode, file, args)
|
|
|
|
def spawnlpe(mode, file, *args):
|
|
"""spawnlpe(mode, file, *args, env) -> integer
|
|
|
|
Execute file (which is looked for along $PATH) with arguments from
|
|
args in a subprocess with the supplied environment.
|
|
If mode == P_NOWAIT return the pid of the process.
|
|
If mode == P_WAIT return the process's exit code if it exits normally;
|
|
otherwise return -SIG, where SIG is the signal that killed it. """
|
|
env = args[-1]
|
|
return spawnvpe(mode, file, args[:-1], env)
|
|
|
|
|
|
__all__.extend(["spawnlp", "spawnlpe"])
|
|
|
|
|
|
# Supply os.popen()
|
|
def popen(cmd, mode="r", buffering=-1):
|
|
if not isinstance(cmd, str):
|
|
raise TypeError("invalid cmd type (%s, expected string)" % type(cmd))
|
|
if mode not in ("r", "w"):
|
|
raise ValueError("invalid mode %r" % mode)
|
|
if buffering == 0 or buffering is None:
|
|
raise ValueError("popen() does not support unbuffered streams")
|
|
import subprocess, io
|
|
if mode == "r":
|
|
proc = subprocess.Popen(cmd,
|
|
shell=True,
|
|
stdout=subprocess.PIPE,
|
|
bufsize=buffering)
|
|
return _wrap_close(io.TextIOWrapper(proc.stdout), proc)
|
|
else:
|
|
proc = subprocess.Popen(cmd,
|
|
shell=True,
|
|
stdin=subprocess.PIPE,
|
|
bufsize=buffering)
|
|
return _wrap_close(io.TextIOWrapper(proc.stdin), proc)
|
|
|
|
# Helper for popen() -- a proxy for a file whose close waits for the process
|
|
class _wrap_close:
|
|
def __init__(self, stream, proc):
|
|
self._stream = stream
|
|
self._proc = proc
|
|
def close(self):
|
|
self._stream.close()
|
|
returncode = self._proc.wait()
|
|
if returncode == 0:
|
|
return None
|
|
if name == 'nt':
|
|
return returncode
|
|
else:
|
|
return returncode << 8 # Shift left to match old behavior
|
|
def __enter__(self):
|
|
return self
|
|
def __exit__(self, *args):
|
|
self.close()
|
|
def __getattr__(self, name):
|
|
return getattr(self._stream, name)
|
|
def __iter__(self):
|
|
return iter(self._stream)
|
|
|
|
# Supply os.fdopen()
|
|
def fdopen(fd, *args, **kwargs):
|
|
if not isinstance(fd, int):
|
|
raise TypeError("invalid fd type (%s, expected integer)" % type(fd))
|
|
import io
|
|
return io.open(fd, *args, **kwargs)
|