uring_tests.c

#include <liburing.h>

#include <err.h>
#include <stdio.h>
#include <string.h> /* bzero(3) */
#include <unistd.h>

int
pipe_bug(int blocking)
{
	struct io_uring_params p;
	struct io_uring ring;
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	char buf[1024];
	int ret;
	int fds[2];

	/* printf("%s blocking=%d\n", __func__, blocking); */

	if (pipe(fds) != 0)
		err(1, "pipe");

	/* explicit_bzero(&p, sizeof(p)); */
	bzero(buf, sizeof(buf));
	bzero(&p, sizeof(p));

	if (!blocking) {
		if (fcntl(fds[0], F_SETFL, O_NONBLOCK) != 0)
			err(1, "fcntl");
		if (fcntl(fds[1], F_SETFL, O_NONBLOCK) != 0)
			err(1, "fcntl");
	}

	if (io_uring_queue_init_params(10, &ring, &p) != 0)
		err(1, "io_uring_queue_init_params");


	/* WRITE */
	sqe = io_uring_get_sqe(&ring);
	if (sqe == NULL)
		errx(1, "no sqe");
	io_uring_prep_write(sqe, fds[1], "foobar", strlen("foobar"), 0); /* or -1 */
	ret = io_uring_submit(&ring);
	if (ret != 1)
		errx(1, "io_uring_submit %d\n", ret);
	ret = io_uring_wait_cqe(&ring, &cqe);
	if (ret != 0)
		errx(1, "io_uring_wait_cqe %d\n", ret);
	io_uring_cqe_seen(&ring, cqe);

	/* CLOSE */
	sqe = io_uring_get_sqe(&ring);
	io_uring_prep_close(sqe, fds[1]);
	ret = io_uring_submit(&ring);
	if (ret != 1)
		errx(1, "io_uring_submit %d\n", ret);
	ret = io_uring_wait_cqe(&ring, &cqe);
	if (ret != 0)
		errx(1, "io_uring_wait_cqe %d\n", ret);
	io_uring_cqe_seen(&ring, cqe);
	/* printf("close cqe->res = %d\n", cqe->res); */

	/* READ */
	sqe = io_uring_get_sqe(&ring);
	if (sqe == NULL)
		errx(1, "no sqe");
	io_uring_prep_read(sqe, fds[0], buf, sizeof(buf), 0); /* or -1 */
	ret = io_uring_submit(&ring);
	if (ret != 1)
		errx(1, "io_uring_submit %d\n", ret);
	ret = io_uring_wait_cqe(&ring, &cqe);
	if (ret != 0)
		errx(1, "io_uring_wait_cqe %d\n", ret);
	io_uring_cqe_seen(&ring, cqe);
	printf("read(A) cqe->res = %d (buf=%s)\n", cqe->res, buf);
	bzero(buf, sizeof(buf));

	/* READ */
	sqe = io_uring_get_sqe(&ring);
	if (sqe == NULL)
		errx(1, "no sqe");
	io_uring_prep_read(sqe, fds[0], buf, sizeof(buf), 0); /* or -1 */
	ret = io_uring_submit(&ring);
	if (ret != 1)
		errx(1, "io_uring_submit %d\n", ret);
	ret = io_uring_wait_cqe(&ring, &cqe);
	if (ret != 0)
		errx(1, "io_uring_wait_cqe %d\n", ret);
	io_uring_cqe_seen(&ring, cqe);
	printf("read(B) cqe->res = %d\n", cqe->res);

	io_uring_queue_exit(&ring);
	
	return (0);
}


int
main(void)
{
	/* plain_read(); */
	pipe_bug(1); /* NEVER SEES EOF */
	/* pipe_bug(0); /* WORKS */

	return (0);
}