view hg @ 27193:c7217f1458bf

commands: make backout acquire locks before processing

Before this patch, "hg backout" executes below before acquisition of
wlock.

  - cmdutil.checkunfinished()
  - cmdutil.bailifchanged()
  - repo.dirstate.parents()

It may cause unintentional result, if another command runs parallelly
(see also issue4368).

In addition to it, "hg backout" refers changelog for purposes below
without acquisition of store lock (slock), and it may cause
unintentional result, if store is updated parallelly.

  - show and update to the revision by 'repo.changelog.tip()'

  - examine for "created new head" by 'repo.branchheads()' and
    'cmdutil.commitstatus()'

To avoid this issue, this patch makes "hg backout" acquire wlock and
slock before processing.

#!/usr/bin/env python
#
# mercurial - scalable distributed SCM
#
# Copyright 2005-2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

import os
import sys

if os.environ.get('HGUNICODEPEDANTRY', False):
    reload(sys)
    sys.setdefaultencoding("undefined")


libdir = '@LIBDIR@'

if libdir != '@' 'LIBDIR' '@':
    if not os.path.isabs(libdir):
        libdir = os.path.join(os.path.dirname(os.path.realpath(__file__)),
                              libdir)
        libdir = os.path.abspath(libdir)
    sys.path.insert(0, libdir)

# enable importing on demand to reduce startup time
try:
    from mercurial import demandimport; demandimport.enable()
except ImportError:
    import sys
    sys.stderr.write("abort: couldn't find mercurial libraries in [%s]\n" %
                     ' '.join(sys.path))
    sys.stderr.write("(check your install and PYTHONPATH)\n")
    sys.exit(-1)

import mercurial.util
import mercurial.dispatch

for fp in (sys.stdin, sys.stdout, sys.stderr):
    mercurial.util.setbinary(fp)

mercurial.dispatch.run()