mercurial/version.py
author Stephen Darnell
Wed, 14 Sep 2005 12:22:20 -0500
changeset 1241 3b4f05ff3130
parent 464 50da4bb9cab6
child 1977 7eb694a1c1af
permissions -rw-r--r--
Add support for cloning with hardlinks on windows. In order to use hardlinks, the win32file module is needed, and this is present in ActivePython. If it isn't present, or hardlinks are not supported on the underlying filesystem, a regular copy is used. When using hardlinks the biggest benefit is probably the saving in space, but cloning can be much quicker. For example cloning the Xen tree (non trivial) without an update goes from about 95s to 15s. Unix-like platforms should be unaffected, although should be more tolerant on filesystems that don't support hard links. (tweaked by mpm to deal with new copyfiles function) --- hg.orig/mercurial/commands.py 2005-09-13 19:32:53.000000000 -0500 +++ hg/mercurial/commands.py 2005-09-14 12:11:34.000000000 -0500 @@ -620,10 +620,6 @@ def clone(ui, source, dest=None, **opts) if other.dev() != -1: abspath = os.path.abspath(source) - copyfile = (os.stat(dest).st_dev == other.dev() - and getattr(os, 'link', None) or shutil.copy2) - if copyfile is not shutil.copy2: - ui.note("cloning by hardlink\n") # we use a lock here because if we race with commit, we can # end up with extra data in the cloned revlogs that's not @@ -638,7 +634,7 @@ def clone(ui, source, dest=None, **opts) for f in files.split(): src = os.path.join(source, ".hg", f) dst = os.path.join(dest, ".hg", f) - util.copyfiles(src, dst, copyfile) + util.copyfiles(src, dst) repo = hg.repository(ui, dest) Index: hg/mercurial/util.py =================================================================== --- hg.orig/mercurial/util.py 2005-09-08 00:15:25.000000000 -0500 +++ hg/mercurial/util.py 2005-09-14 12:16:49.000000000 -0500 @@ -12,7 +12,7 @@ platform-specific details from the core. import os, errno from demandload import * -demandload(globals(), "re cStringIO") +demandload(globals(), "re cStringIO shutil") def binary(s): """return true if a string is binary data using diff's heuristic""" @@ -217,17 +217,28 @@ def rename(src, dst): os.unlink(dst) os.rename(src, dst) -def copyfiles(src, dst, copyfile): - """Copy a directory tree, files are copied using 'copyfile'.""" +def copyfiles(src, dst, hardlink=None): + """Copy a directory tree using hardlinks if possible""" + + if hardlink is None: + hardlink = (os.stat(src).st_dev == + os.stat(os.path.dirname(dst)).st_dev) if os.path.isdir(src): os.mkdir(dst) for name in os.listdir(src): srcname = os.path.join(src, name) dstname = os.path.join(dst, name) - copyfiles(srcname, dstname, copyfile) + copyfiles(srcname, dstname, hardlink) else: - copyfile(src, dst) + if hardlink: + try: + os_link(src, dst) + except: + hardlink = False + shutil.copy2(src, dst) + else: + shutil.copy2(src, dst) def opener(base): """ @@ -244,13 +255,13 @@ def opener(base): if mode[0] != "r": try: - s = os.stat(f) + nlink = nlinks(f) except OSError: d = os.path.dirname(f) if not os.path.isdir(d): os.makedirs(d) else: - if s.st_nlink > 1: + if nlink > 1: file(f + ".tmp", "wb").write(file(f, "rb").read()) rename(f+".tmp", f) @@ -266,10 +277,41 @@ def _makelock_file(info, pathname): def _readlock_file(pathname): return file(pathname).read() +def nlinks(pathname): + """Return number of hardlinks for the given file.""" + return os.stat(pathname).st_nlink + +if hasattr(os, 'link'): + os_link = os.link +else: + def os_link(src, dst): + raise OSError(0, "Hardlinks not supported") + # Platform specific variants if os.name == 'nt': nulldev = 'NUL:' + try: # ActivePython can create hard links using win32file module + import win32file + + def os_link(src, dst): # NB will only succeed on NTFS + win32file.CreateHardLink(dst, src) + + def nlinks(pathname): + """Return number of hardlinks for the given file.""" + try: + fh = win32file.CreateFile(pathname, + win32file.GENERIC_READ, win32file.FILE_SHARE_READ, + None, win32file.OPEN_EXISTING, 0, None) + res = win32file.GetFileInformationByHandle(fh) + fh.Close() + return res[7] + except: + return os.stat(pathname).st_nlink + + except ImportError: + pass + def is_exec(f, last): return last

# Copyright (C) 2005 by Intevation GmbH
# Author(s):
# Thomas Arendsen Hein <thomas@intevation.de>
#
# This program is free software under the GNU GPL (>=v2)
# Read the file COPYING coming with the software for details.

"""
Mercurial version
"""

import os
import os.path
import re
import time
import util

unknown_version = 'unknown'
remembered_version = False

def get_version():
    """Return version information if available."""
    try:
        from mercurial.__version__ import version
    except ImportError:
        version = unknown_version
    return version

def write_version(version):
    """Overwrite version file."""
    filename = os.path.join(os.path.dirname(__file__), '__version__.py')
    f = open(filename, 'w')
    f.write("# This file is auto-generated.\n")
    f.write("version = %r\n" % version)
    f.close()

def remember_version(version=None):
    """Store version information."""
    global remembered_version
    if not version and os.path.isdir(".hg"):
        f = os.popen("hg identify 2> %s" % util.nulldev)  # use real hg installation
        ident = f.read()[:-1]
        if not f.close() and ident:
            ids = ident.split(' ', 1)
            version = ids.pop(0)
            if version[-1] == '+':
                version = version[:-1]
                modified = True
            else:
                modified = False
            if version.isalnum() and ids:
                for tag in ids[0].split('/'):
                    # is a tag is suitable as a version number?
                    if re.match(r'^(\d+\.)+[\w.-]+$', tag):
                        version = tag
                        break
            if modified:
                version += time.strftime('+%Y%m%d')
    if version:
        remembered_version = True
        write_version(version)

def forget_version():
    """Remove version information."""
    if remembered_version:
        write_version(unknown_version)