Revision e6c200d6 lib/locking.py

b/lib/locking.py
377 377 
    else:
378 378 
      names.sort()
379 379 

  		





  380
  
  
    
    # Now names contains a sorted list of resources whose lock we want to


  		





  381
  
  
    
    # acquire. In order to get them we loop on this (private) list and look


  		





  382
  
  
    
    # them up in __lockdict. Since we have no lock held on lockdict we have no


  		





  383
  
  
    
    # guarantees on their presence, and they may even disappear after we looked


  		





  384
  
  
    
    # them up. This is fine though as .acquire() itself is safe and will alert


  		





  385
  
  
    
    # us if the lock gets deleted.


  		





  386
  
  
    

  		





  
  380
  
    
    acquire_list = []


  		





  
  381
  
    
    # First we look the locks up on __lockdict. We have no way of being sure


  		





  
  382
  
    
    # they will still be there after, but this makes it a lot faster should


  		





  
  383
  
    
    # just one of them be the already wrong


  		





  387
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    try:


  		





  388
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      for lname in names:


  		





  389
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        lock = self.__lockdict[lname] # raises KeyError if the lock is not there


  		





  
  387
  
    
        acquire_list.append((lname, lock))


  		





  
  388
  
    
    except (KeyError):


  		





  
  389
  
    
      raise errors.LockError('non-existing lock in set (%s)' % lname)


  		





  
  390
  
    

  		





  
  391
  
    
    # Now acquire_list contains a sorted list of resources and locks we want.


  		





  
  392
  
    
    # In order to get them we loop on this (private) list and acquire() them.


  		





  
  393
  
    
    # We gave no real guarantee they will still exist till this is done but


  		





  
  394
  
    
    # .acquire() itself is safe and will alert us if the lock gets deleted.


  		





  
  395
  
    
    try:


  		





  
  396
  
    
      for (lname, lock) in acquire_list:


  		





  390
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        lock.acquire(shared=shared) # raises LockError if the lock is deleted


  		





  391
  398
  
    
        try:


  		





  392
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          # now the lock cannot be deleted, we have it!


  		





  ......




  398
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          lock.release()


  		





  399
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          raise


  		





  400
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  401
  
  
    
    except (KeyError, errors.LockError):


  		





  
  408
  
    
    except (errors.LockError):


  		





  402
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      name_fail = lname


  		





  403
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      for lname in self._list_owned():


  		





  404
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        self.__lockdict[lname].release()


  		












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