datastore_file_stub.py 文件源码

def __WritePickled(self, obj, filename):
    """Pickles the object and writes it to the given file.
    """
    if not filename or filename == '/dev/null' or not obj:
      return


    descriptor, tmp_filename = tempfile.mkstemp(dir=os.path.dirname(filename))
    tmpfile = os.fdopen(descriptor, 'wb')





    pickler = pickle.Pickler(tmpfile, protocol=1)
    pickler.fast = True
    pickler.dump(obj)

    tmpfile.close()

    self.__file_lock.acquire()
    try:
      try:

        os.rename(tmp_filename, filename)
      except OSError:

        try:
          os.remove(filename)
        except:
          pass
        os.rename(tmp_filename, filename)
    finally:
      self.__file_lock.release()