mercurial/windows.py

9591:012f1244cd4c

# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

from i18n import _
import osutil, error
import errno, msvcrt, os, re, sys

nulldev = 'NUL:'
umask = 002

# wrap osutil.posixfile to provide friendlier exceptions

    try:
        _removedirs(os.path.dirname(f))
    except OSError:
        pass

try:
    # override functions with win32 versions if possible
    from win32 import *
except ImportError:
    pass

9592:5ebeef7cc201

# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

from i18n import _
import osutil, error
import errno, msvcrt, os, re, sys, random

nulldev = 'NUL:'
umask = 002

# wrap osutil.posixfile to provide friendlier exceptions

    try:
        _removedirs(os.path.dirname(f))
    except OSError:
        pass

def rename(src, dst):
    '''atomically rename file src to dst, replacing dst if it exists'''
    try:
        os.rename(src, dst)
    except OSError, err: # FIXME: check err (EEXIST ?)

        # On windows, rename to existing file is not allowed, so we
        # must delete destination first. But if a file is open, unlink
        # schedules it for delete but does not delete it. Rename
        # happens immediately even for open files, so we rename
        # destination to a temporary name, then delete that. Then
        # rename is safe to do.
        # The temporary name is chosen at random to avoid the situation
        # where a file is left lying around from a previous aborted run.
        # The usual race condition this introduces can't be avoided as
        # we need the name to rename into, and not the file itself. Due
        # to the nature of the operation however, any races will at worst
        # lead to the rename failing and the current operation aborting.

        def tempname(prefix):
            for tries in xrange(10):
                temp = '%s-%08x' % (prefix, random.randint(0, 0xffffffff))
                if not os.path.exists(temp):
                    return temp
            raise IOError, (errno.EEXIST, "No usable temporary filename found")

        temp = tempname(dst)
        os.rename(dst, temp)
        try:
            os.unlink(temp)
        except:
            # Some rude AV-scanners on Windows may cause the unlink to
            # fail. Not aborting here just leaks the temp file, whereas
            # aborting at this point may leave serious inconsistencies.
            # Ideally, we would notify the user here.
            pass
        os.rename(src, dst)

try:
    # override functions with win32 versions if possible
    from win32 import *
except ImportError:
    pass