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Viewing changes to bzrlib/lock.py

  • Committer: Andrew Bennetts
  • Date: 2009-12-03 02:24:54 UTC
  • mfrom: (4634.101.4 2.0)
  • mto: This revision was merged to the branch mainline in revision 4857.
  • Revision ID: andrew.bennetts@canonical.com-20091203022454-m2gyhbcdqi1t7ujz
Merge lp:bzr/2.0 into lp:bzr.

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bzrlib/lock.py
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# Copyright (C) 2005-2010 Canonical Ltd
 
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# Copyright (C) 2005, 2006, 2007, 2008, 2009 Canonical Ltd
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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"""Locking using OS file locks or file existence.
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Note: This method of locking is generally deprecated in favour of LockDir, but
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unlock() method.
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"""
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from __future__ import absolute_import
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import errno
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import os
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import sys
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    osutils,
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    trace,
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    )
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from bzrlib.hooks import Hooks
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from bzrlib.i18n import gettext
 
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from bzrlib.hooks import HookPoint, Hooks
 
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class LockHooks(Hooks):
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    def __init__(self):
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        Hooks.__init__(self, "bzrlib.lock", "Lock.hooks")
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        self.add_hook('lock_acquired',
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
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            "acquired.", (1, 8))
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        self.add_hook('lock_released',
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
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            "released.", (1, 8))
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        self.add_hook('lock_broken',
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
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            "broken.", (1, 15))
 
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        Hooks.__init__(self)
 
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        self.create_hook(HookPoint('lock_acquired',
 
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
 
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            "acquired.", (1, 8), None))
 
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        self.create_hook(HookPoint('lock_released',
 
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
 
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            "released.", (1, 8), None))
 
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        self.create_hook(HookPoint('lock_broken',
 
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            "Called with a bzrlib.lock.LockResult when a physical lock is "
 
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            "broken.", (1, 15), None))
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class Lock(object):
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        return self.lock_url == other.lock_url and self.details == other.details
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    def __repr__(self):
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        return '%s(%s, %s)' % (self.__class__.__name__,
 
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        return '%s(%s%s)' % (self.__class__.__name__,
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                             self.lock_url, self.details)
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class LogicalLockResult(object):
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    """The result of a lock_read/lock_write/lock_tree_write call on lockables.
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    :ivar unlock: A callable which will unlock the lock.
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    """
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    def __init__(self, unlock):
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        self.unlock = unlock
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    def __repr__(self):
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        return "LogicalLockResult(%s)" % (self.unlock)
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def cant_unlock_not_held(locked_object):
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    """An attempt to unlock failed because the object was not locked.
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            self.f.close()
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            self.f = None
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    def __del__(self):
 
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        if self.f:
 
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            from warnings import warn
 
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            warn("lock on %r not released" % self.f)
 
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            self.unlock()
 
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    def unlock(self):
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        raise NotImplementedError()
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            self._open(self.filename, 'rb+')
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            # reserve a slot for this lock - even if the lockf call fails,
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            # at this point unlock() will be called, because self.f is set.
 
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            # at thisi point unlock() will be called, because self.f is set.
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            # TODO: make this fully threadsafe, if we decide we care.
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            _fcntl_WriteLock._open_locks.add(self.filename)
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            try:
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    locked the same way), and -Drelock is set, then this will trace.note a
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    message about it.
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    """
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    _prev_lock = None
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    def _note_lock(self, lock_type):
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                type_name = 'read'
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            else:
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                type_name = 'write'
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            trace.note(gettext('{0!r} was {1} locked again'), self, type_name)
 
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            trace.note('%r was %s locked again', self, type_name)
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        self._prev_lock = lock_type
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