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  • Committer: Canonical.com Patch Queue Manager
  • Date: 2010-05-11 11:47:36 UTC
  • mfrom: (5200.3.8 lock_return)
  • Revision ID: pqm@pqm.ubuntu.com-20100511114736-mc1sq9zyo3vufec7
(lifeless) Provide a consistent interface to Tree, Branch,
 Repository where lock methods return an object with an unlock method to
 unlock the lock. This breaks the API for Branch,
 Repository on their lock_write methods. (Robert Collins)

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Lines of Context:
bzrlib/branch.py
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from bzrlib.decorators import needs_read_lock, needs_write_lock, only_raises
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from bzrlib.hooks import HookPoint, Hooks
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from bzrlib.inter import InterObject
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from bzrlib.lock import _RelockDebugMixin
 
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from bzrlib.lock import _RelockDebugMixin, LogicalLockResult
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from bzrlib import registry
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from bzrlib.symbol_versioning import (
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    deprecated_in,
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        new_history.reverse()
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        return new_history
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    def lock_write(self):
 
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    def lock_write(self, token=None):
 
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        """Lock the branch for write operations.
 
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        :param token: A token to permit reacquiring a previously held and
 
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            preserved lock.
 
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        :return: A BranchWriteLockResult.
 
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        """
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        raise NotImplementedError(self.lock_write)
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    def lock_read(self):
 
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        """Lock the branch for read operations.
 
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        :return: A bzrlib.lock.LogicalLockResult.
 
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        """
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        raise NotImplementedError(self.lock_read)
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    def unlock(self):
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    _legacy_formats[0].network_name(), _legacy_formats[0].__class__)
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class BranchWriteLockResult(LogicalLockResult):
 
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    """The result of write locking a branch.
 
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    :ivar branch_token: The token obtained from the underlying branch lock, or
 
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        None.
 
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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, branch_token):
 
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        LogicalLockResult.__init__(self, unlock)
 
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        self.branch_token = branch_token
 
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    def __repr__(self):
 
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        return "BranchWriteLockResult(%s, %s)" % (self.branch_token,
 
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            self.unlock)
 
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class BzrBranch(Branch, _RelockDebugMixin):
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    """A branch stored in the actual filesystem.
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        return self.control_files.is_locked()
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    def lock_write(self, token=None):
 
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        """Lock the branch for write operations.
 
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        :param token: A token to permit reacquiring a previously held and
 
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            preserved lock.
 
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        :return: A BranchWriteLockResult.
 
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        """
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        if not self.is_locked():
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            self._note_lock('w')
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        # All-in-one needs to always unlock/lock.
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        else:
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            took_lock = False
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        try:
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            return self.control_files.lock_write(token=token)
 
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            return BranchWriteLockResult(self.unlock,
 
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                self.control_files.lock_write(token=token))
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        except:
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            if took_lock:
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                self.repository.unlock()
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            raise
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    def lock_read(self):
 
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        """Lock the branch for read operations.
 
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        :return: A bzrlib.lock.LogicalLockResult.
 
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        """
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        if not self.is_locked():
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            self._note_lock('r')
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        # All-in-one needs to always unlock/lock.
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            took_lock = False
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        try:
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            self.control_files.lock_read()
 
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            return LogicalLockResult(self.unlock)
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        except:
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            if took_lock:
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                self.repository.unlock()