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Viewing changes to bzrlib/workingtree.py

  • Committer: Robert Collins
  • Date: 2006-09-10 22:50:11 UTC
  • mto: This revision was merged to the branch mainline in revision 2000.
  • Revision ID: robertc@robertcollins.net-20060910225011-c46f2b78a0f5cb7d
Add WorkingTree.lock_tree_write.

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Lines of Context:
bzrlib/workingtree.py
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    return gen_file_id('TREE_ROOT')
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def needs_tree_write_lock(unbound):
 
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    """Decorate unbound to take out and release a tree_write lock."""
 
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    def tree_write_locked(self, *args, **kwargs):
 
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        self.lock_tree_write()
 
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        try:
 
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            return unbound(self, *args, **kwargs)
 
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        finally:
 
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            self.unlock()
 
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    tree_write_locked.__doc__ = unbound.__doc__
 
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    tree_write_locked.__name__ = unbound.__name__
 
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    return tree_write_locked
 
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class TreeEntry(object):
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    """An entry that implements the minimum interface used by commands.
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            self.branch.unlock()
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            raise
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    def lock_tree_write(self):
 
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        """Lock the working tree for write, and the branch for read.
 
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        This is useful for operations which only need to mutate the working
 
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        tree. Taking out branch write locks is a relatively expensive process
 
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        and may fail if the branch is on read only media. So branch write locks
 
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        should only be taken out when we are modifying branch data - such as in
 
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        operations like commit, pull, uncommit and update.
 
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        """
 
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        self.branch.lock_read()
 
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        try:
 
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            return self._control_files.lock_write()
 
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        except:
 
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            self.branch.unlock()
 
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            raise
 
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    def lock_write(self):
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        """See Branch.lock_write, and WorkingTree.unlock."""
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        self.branch.lock_write()
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     - uses the branch last-revision.
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    """
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    def lock_tree_write(self):
 
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        """See WorkingTree.lock_tree_write().
 
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        In Format2 WorkingTrees we have a single lock for the branch and tree
 
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        so lock_tree_write() degrades to lock_write().
 
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        """
 
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        self.branch.lock_write()
 
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        try:
 
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            return self._control_files.lock_write()
 
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        except:
 
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            self.branch.unlock()
 
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            raise
 
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    def unlock(self):
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        # we share control files:
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        if self._hashcache.needs_write and self._control_files._lock_count==3: