wsgi.py 文件源码

def run_child(self):
        def child_hup(*args):
            """Shuts down child processes, existing requests are handled."""
            signal.signal(signal.SIGHUP, signal.SIG_IGN)
            eventlet.wsgi.is_accepting = False
            self.sock.close()

        pid = os.fork()
        if pid == 0:
            signal.signal(signal.SIGHUP, child_hup)
            signal.signal(signal.SIGTERM, signal.SIG_DFL)
            # ignore the interrupt signal to avoid a race whereby
            # a child worker receives the signal before the parent
            # and is respawned unnecessarily as a result
            signal.signal(signal.SIGINT, signal.SIG_IGN)
            # The child has no need to stash the unwrapped
            # socket, and the reference prevents a clean
            # exit on sighup
            self._sock = None
            self.run_server()
            LOG.info(_LI('Child %d exiting normally'), os.getpid())
            # self.pool.waitall() is now called in wsgi's server so
            # it's safe to exit here
            sys.exit(0)
        else:
            LOG.info(_LI('Started child %s'), pid)
            self.children.add(pid)