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Viewing changes to bzrlib/lock.py

  • Committer: Patch Queue Manager
  • Date: 2016-04-21 05:06:57 UTC
  • mfrom: (6603.4.1 bzr)
  • Revision ID: pqm@pqm.ubuntu.com-20160421050657-ygnzfybewvudf1j9
(richard-wilbur) Use initial_comment as commit_message for lp_propose.(Shawn
 Wang) (Shawn Wang)

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bzrlib/lock.py
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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 contextlib
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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 HookPoint, Hooks
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from bzrlib.hooks import Hooks
 
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from bzrlib.i18n import gettext
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class LockHooks(Hooks):
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    def __init__(self):
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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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        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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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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    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('%r was %s locked again', self, type_name)
 
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            trace.note(gettext('{0!r} was {1} locked again'), self, type_name)
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        self._prev_lock = lock_type
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@contextlib.contextmanager
 
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def write_locked(lockable):
 
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    lockable.lock_write()
 
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    try:
 
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        yield lockable
 
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    finally:
 
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        lockable.unlock()