Function __submit_receive

examples/proxy.c:683–734

}

static void __submit_receive(struct io_uring *ring, struct conn *c,
			     struct conn_dir *cd, int fd)
{
	struct conn_buf_ring *cbr = &c->in_br;
	struct io_uring_sqe *sqe;

	vlog("%d: submit receive fd=%d\n", c->tid, fd);

	assert(!cd->pending_recv);
	cd->pending_recv = 1;

	/*
	 * For both recv and multishot receive, we use the ring provided
	 * buffers. These are handed to the application ahead of time, and
	 * are consumed when a receive triggers. Note that the address and
	 * length of the receive are set to NULL/0, and we assign the
	 * sqe->buf_group to tell the kernel which buffer group ID to pick
	 * a buffer from. Finally, IOSQE_BUFFER_SELECT is set to tell the
	 * kernel that we want a buffer picked for this request, we are not
	 * passing one in with the request.
	 */
	sqe = get_sqe(ring);
	if (rcv_msg) {
		struct io_msg *imsg = &cd->io_rcv_msg;
		struct msghdr *msg = &imsg->msg;

		memset(msg, 0, sizeof(*msg));
		msg->msg_iov = msg_vec(imsg)->iov;
		msg->msg_iovlen = msg_vec(imsg)->iov_len;

		if (recv_mshot) {
			cd->rcv_mshot++;
			io_uring_prep_recvmsg_multishot(sqe, fd, &imsg->msg, 0);
		} else {
			io_uring_prep_recvmsg(sqe, fd, &imsg->msg, 0);
		}
	} else {
		if (recv_mshot) {
			cd->rcv_mshot++;
			io_uring_prep_recv_multishot(sqe, fd, NULL, 0, 0);
		} else {
			io_uring_prep_recv(sqe, fd, NULL, 0, 0);
		}
	}
	encode_userdata(sqe, c, __RECV, 0, fd);
	sqe->buf_group = cbr->bgid;
	sqe->flags |= IOSQE_BUFFER_SELECT;
	if (fixed_files)
		sqe->flags |= IOSQE_FIXED_FILE;
	if (rcv_bundle)
		sqe->ioprio |= IORING_RECVSEND_BUNDLE;
}

/*
 * One directional just arms receive on our in_fd