Called when the process has stopped.

        :param returncode: Process returncode

def _termination_callback(self, returncode):
        """
        Called when the process has stopped.

        :param returncode: Process returncode
        """

        if self.status == "started":
            self.status = "stopped"
            log.info("Dynamips hypervisor process has stopped, return code: %d", returncode)
            if returncode != 0:
                self.project.emit("log.error", {"message": "Dynamips hypervisor process has stopped, return code: {}\n{}".format(returncode, self._hypervisor.read_stdout())})