Function recv_mshot_msg

examples/proxy.c:1227–1278

* Special handling of recvmsg with multishot */

 * Special handling of recvmsg with multishot
 */
static int recv_mshot_msg(struct conn *c, struct conn_dir *cd, int *bid,
			  int in_bytes)
{
	struct conn_buf_ring *cbr = &c->out_br;
	struct conn_buf_ring *in_cbr = &c->in_br;
	struct io_uring_buf *buf;
	int nr_packets = 0;

	while (in_bytes) {
		struct io_uring_recvmsg_out *pdu;
		int this_bytes;
		void *data;

		buf = &in_cbr->br->bufs[*bid];

		/*
		 * multishot recvmsg puts a header in front of the data - we
		 * have to take that into account for the send setup, and
		 * adjust the actual data read to not take this metadata into
		 * account. For this use case, namelen and controllen will not
		 * be set. If they were, they would need to be factored in too.
		 */
		buf->len -= sizeof(struct io_uring_recvmsg_out);
		in_bytes -= sizeof(struct io_uring_recvmsg_out);

		pdu = (void *) (unsigned long) buf->addr;
		vlog("pdu namelen %d, controllen %d, payload %d flags %x\n",
				pdu->namelen, pdu->controllen, pdu->payloadlen,
				pdu->flags);
		data = (void *) (pdu + 1);

		this_bytes = pdu->payloadlen;
		if (this_bytes > in_bytes)
			this_bytes = in_bytes;

		in_bytes -= this_bytes;

		if (send_ring)
			io_uring_buf_ring_add(cbr->br, data, this_bytes, *bid,
						br_mask, nr_packets);
		else
			send_append(c, cd, data, *bid, this_bytes);

		*bid = (*bid + 1) & (nr_bufs - 1);
		nr_packets++;
	}

	if (send_ring)
		io_uring_buf_ring_advance(cbr->br, nr_packets);

	return nr_packets;
}

static int __handle_recv(struct io_uring *ring, struct conn *c,
			 struct conn_dir *cd, struct io_uring_cqe *cqe)