오픈소스로 공부하는 Strongswan코드와 C예제.

- Strongswan에서는 sender라는 구조체를 통해서 패킷을 전달함.

 

 

원본 코드

/**
 * Job callback function to send packets
 */
static job_requeue_t send_packets(private_sender_t *this)
{
	packet_t *packet;
	bool oldstate;

	this->mutex->lock(this->mutex);
	while (this->list->get_count(this->list) == 0)
	{
		/* add cleanup handler, wait for packet, remove cleanup handler */
		thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex);
		oldstate = thread_cancelability(TRUE);

		this->got->wait(this->got, this->mutex);

		thread_cancelability(oldstate);
		thread_cleanup_pop(FALSE);
	}
	this->list->remove_first(this->list, (void**)&packet);
	this->sent->signal(this->sent);
	this->mutex->unlock(this->mutex);

	charon->socket->send(charon->socket, packet);
	packet->destroy(packet);
	return JOB_REQUEUE_DIRECT;
}

 

 

설명

/**
 * Job callback function to send packets
 */
static job_requeue_t send_packets(private_sender_t *this)
{
	packet_t *packet;
	bool oldstate;

    // 뮤텍스 락
    // critical section start
	this->mutex->lock(this->mutex);
	while (this->list->get_count(this->list) == 0)
	{
		/* add cleanup handler, wait for packet, remove cleanup handler */
		thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex);
		oldstate = thread_cancelability(TRUE);

		this->got->wait(this->got, this->mutex);

		thread_cancelability(oldstate);
		thread_cleanup_pop(FALSE);
	}
	this->list->remove_first(this->list, (void**)&packet);
	this->sent->signal(this->sent);
    
    // critical section end
    // 뮤텍스 언락
	this->mutex->unlock(this->mutex);

    // 보내기 수행.
	charon->socket->send(charon->socket, packet);
	packet->destroy(packet);
	return JOB_REQUEUE_DIRECT;
}