Synnefo » snf-ganeti

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

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

    # just one of them be the already wrong

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

        acquire_list.append((lname, lock))

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

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

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

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

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

        try:

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

          lock.release()

          raise

    return True