static void mctp_tx_task()

in common/mctp/mctp.c [230:332]

• 72 lines of code
• 15 McCabe index (conditional complexity)

static void mctp_tx_task(void *arg, void *dummy0, void *dummy1)
{
	ARG_UNUSED(dummy0);
	ARG_UNUSED(dummy1);
	if (!arg) {
		LOG_WRN("mctp_tx_task without mctp_inst!");
		return;
	}

	mctp *mctp_inst = (mctp *)arg;

	if (!mctp_inst->write_data) {
		LOG_WRN("mctp_tx_task without medium write function!");
		return;
	}

	LOG_INF("mctp_tx_task start %p ", mctp_inst);

	while (1) {
		mctp_tx_msg mctp_msg = { 0 };
		int ret = k_msgq_get(&mctp_inst->mctp_tx_queue, &mctp_msg, K_FOREVER);
		if (ret)
			continue;

		if (!mctp_msg.buf)
			continue;

		if (!mctp_msg.len) {
			free(mctp_msg.buf);
			continue;
		}

		LOG_DBG("tx endpoint %x", mctp_msg.ext_params.ep);
		LOG_HEXDUMP_DBG(mctp_msg.buf, mctp_msg.len, "mctp tx task receive data");

		/*
* The bridge meesage already has the mctp transport header, and the bridge
     * message also doesn't need to split packet.
*/
		if (mctp_msg.is_bridge_packet) {
			mctp_inst->write_data(mctp_inst, mctp_msg.buf, mctp_msg.len,
					      mctp_msg.ext_params);
			free(mctp_msg.buf);
			continue;
		}

		/* Setup MCTP header and send to destination endpoint */
		static uint8_t msg_tag;
		uint16_t max_msg_size = mctp_inst->max_msg_size;
		uint8_t i;
		uint8_t split_pkt_num =
			(mctp_msg.len / max_msg_size) + ((mctp_msg.len % max_msg_size) ? 1 : 0);
		LOG_DBG("mctp_msg.len = %d", mctp_msg.len);
		LOG_DBG("split_pkt_num = %d", split_pkt_num);
		for (i = 0; i < split_pkt_num; i++) {
			uint8_t buf[max_msg_size + MCTP_TRANSPORT_HEADER_SIZE];
			mctp_hdr *hdr = (mctp_hdr *)buf;
			uint8_t cp_msg_size = max_msg_size;

			memset(buf, 0, sizeof(buf));

			/* The first packet should set SOM */
			if (!i)
				hdr->som = 1;

			/* The last packet should set EOM */
			if (i == (split_pkt_num - 1)) {
				hdr->eom = 1;
				uint8_t remain = mctp_msg.len % max_msg_size;
				cp_msg_size = remain ? remain : max_msg_size; /* remain data */
			}

			hdr->to = mctp_msg.ext_params.tag_owner;
			hdr->pkt_seq = i & MCTP_HDR_SEQ_MASK;

			/*
* TODO: should avoid the msg_tag if there are pending mctp
* response packets?
       * If the message is response, keep the original msg_tag of ext_params
*/
			hdr->msg_tag = (hdr->to) ? (msg_tag & MCTP_HDR_TAG_MASK) :
							 mctp_msg.ext_params.msg_tag;

			hdr->dest_ep = mctp_msg.ext_params.ep;
			hdr->src_ep = mctp_inst->endpoint;
			hdr->hdr_ver = MCTP_HDR_HDR_VER;

			LOG_DBG("i = %d, cp_msg_size = %d", i, cp_msg_size);
			LOG_DBG("hdr->flags_seq_to_tag = %x", hdr->flags_seq_to_tag);
			memcpy(buf + MCTP_TRANSPORT_HEADER_SIZE, mctp_msg.buf + i * max_msg_size,
			       cp_msg_size);
			mctp_inst->write_data(mctp_inst, buf,
					      cp_msg_size + MCTP_TRANSPORT_HEADER_SIZE,
					      mctp_msg.ext_params);
		}

		free(mctp_msg.buf);

		/* Only request mctp message needs to increase msg_tag */
		if (mctp_msg.ext_params.tag_owner)
			msg_tag++;
	}
}