Synnefo » snf-ganeti » ganeti-local

def SignalHandled(signums):

  """Signal Handled decoration.

  This special decorator installs a signal handler and then calls the target

  function. The function must accept a 'signal_handlers' keyword argument,

  which will contain a dict indexed by signal number, with SignalHandler

  objects as values.

  The decorator can be safely stacked with iself, to handle multiple signals

  with different handlers.

  @type signums: list

  @param signums: signals to intercept

  """

  def wrap(fn):

    def sig_function(*args, **kwargs):

      assert 'signal_handlers' not in kwargs or \

             kwargs['signal_handlers'] is None or \

             isinstance(kwargs['signal_handlers'], dict), \

             "Wrong signal_handlers parameter in original function call"

      if 'signal_handlers' in kwargs and kwargs['signal_handlers'] is not None:

        signal_handlers = kwargs['signal_handlers']

      else:

        signal_handlers = {}

        kwargs['signal_handlers'] = signal_handlers

      sighandler = SignalHandler(signums)

      try:

        for sig in signums:

          signal_handlers[sig] = sighandler

        return fn(*args, **kwargs)

      finally:

        sighandler.Reset()

    return sig_function

  return wrap