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Viewing changes to bzrlib/counted_lock.py

  • Committer: Martin Pool
  • Date: 2009-03-24 04:49:51 UTC
  • mfrom: (3407.2.20 controlfiles)
  • mto: This revision was merged to the branch mainline in revision 4202.
  • Revision ID: mbp@sourcefrog.net-20090324044951-k5h6x6u0zz4721m5
bzrdir takes responsibility for file/directory unix modes

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bzrlib/counted_lock.py
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    This can be used with any object that provides a basic Lock interface,
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    including LockDirs and OS file locks.
 
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    :ivar _token: While a write lock is held, this is the token 
 
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        for it.
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    """
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    def __init__(self, real_lock):
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            self._lock_count = 1
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            self._lock_mode = 'r'
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    def lock_write(self):
 
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    def lock_write(self, token=None):
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        """Acquire the lock in write mode.
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        If the lock was originally acquired in read mode this will fail.
 
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        :param token: If given and the lock is already held, 
 
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            then validate that we already hold the real
 
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            lock with this token.
 
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        :returns: The token from the underlying lock.
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        """
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        if self._lock_count == 0:
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            self._real_lock.lock_write()
 
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            self._token = self._real_lock.lock_write(token=token)
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            self._lock_mode = 'w'
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        elif self._lock_mode != 'w':
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            raise ReadOnlyError(self)
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        self._lock_count += 1
 
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        return self._token
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    def unlock(self):
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        if self._lock_count == 0: