/* SPDX-License-Identifier: MIT */

/*

 * Description: run various timeout tests

 *

 */

#include <errno.h>

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <fcntl.h>

#include <sys/time.h>

#include "liburing.h"

#include "../src/syscall.h"

#define TIMEOUT_MSEC	200

static int not_supported;

static int no_modify;

static void msec_to_ts(struct __kernel_timespec *ts, unsigned int msec)

{

	ts->tv_sec = msec / 1000;

	ts->tv_nsec = (msec % 1000) * 1000000;

}

static unsigned long long mtime_since(const struct timeval *s,

				      const struct timeval *e)

{

	long long sec, usec;

	sec = e->tv_sec - s->tv_sec;

	usec = (e->tv_usec - s->tv_usec);

	if (sec > 0 && usec < 0) {

		sec--;

		usec += 1000000;

	}

	sec *= 1000;

	usec /= 1000;

	return sec + usec;

}

static unsigned long long mtime_since_now(struct timeval *tv)

{

	struct timeval end;

	gettimeofday(&end, NULL);

	return mtime_since(tv, &end;;

}

/*

 * Test that we return to userspace if a timeout triggers, even if we

 * don't satisfy the number of events asked for.

 */

static int test_single_timeout_many(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	unsigned long long exp;

	struct __kernel_timespec ts;

	struct timeval tv;

	int ret;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, TIMEOUT_MSEC);

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	gettimeofday(&tv, NULL);

	ret = __sys_io_uring_enter(ring->ring_fd, 0, 4, IORING_ENTER_GETEVENTS,

					NULL);

	if (ret < 0) {

		fprintf(stderr, "%s: io_uring_enter %d\n", __FUNCTION__, ret);

		goto err;

	}

	ret = io_uring_wait_cqe(ring, &cqe);

	if (ret < 0) {

		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

		goto err;

	}

	ret = cqe->res;

	io_uring_cqe_seen(ring, cqe);

	if (ret == -EINVAL) {

		fprintf(stdout, "Timeout not supported, ignored\n");

		not_supported = 1;

		return 0;

	} else if (ret != -ETIME) {

		fprintf(stderr, "Timeout: %s\n", strerror(-ret));

		goto err;

	}

	exp = mtime_since_now(&tv;;

	if (exp >= TIMEOUT_MSEC / 2 && exp <= (TIMEOUT_MSEC * 3) / 2)

		return 0;

	fprintf(stderr, "%s: Timeout seems wonky (got %llu)\n", __FUNCTION__, exp);

err:

	return 1;

}

/*

 * Test numbered trigger of timeout

 */

static int test_single_timeout_nr(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	struct __kernel_timespec ts;

	int i, ret;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, TIMEOUT_MSEC);

	io_uring_prep_timeout(sqe, &ts, 2, 0);

	sqe = io_uring_get_sqe(ring);

	io_uring_prep_nop(sqe);

	io_uring_sqe_set_data(sqe, (void *) 1);

	sqe = io_uring_get_sqe(ring);

	io_uring_prep_nop(sqe);

	io_uring_sqe_set_data(sqe, (void *) 1);

	ret = io_uring_submit_and_wait(ring, 3);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	i = 0;

	while (i < 3) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		/*

		 * NOP commands have user_data as 1. Check that we get the

		 * two NOPs first, then the successfully removed timout as

		 * the last one.

		 */

		switch (i) {

		case 0:

		case 1:

			if (io_uring_cqe_get_data(cqe) != (void *) 1) {

				fprintf(stderr, "%s: nop not seen as 1 or 2\n", __FUNCTION__);

				goto err;

			}

			break;

		case 2:

			if (io_uring_cqe_get_data(cqe) != NULL) {

				fprintf(stderr, "%s: timeout not last\n", __FUNCTION__);

				goto err;

			}

			break;

		}

		ret = cqe->res;

		io_uring_cqe_seen(ring, cqe);

		if (ret < 0) {

			fprintf(stderr, "Timeout: %s\n", strerror(-ret));

			goto err;

		} else if (ret) {

			fprintf(stderr, "res: %d\n", ret);

			goto err;

		}

		i++;

	};

	return 0;

err:

	return 1;

}

static int test_single_timeout_wait(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	struct __kernel_timespec ts;

	int i, ret;

	sqe = io_uring_get_sqe(ring);

	io_uring_prep_nop(sqe);

	io_uring_sqe_set_data(sqe, (void *) 1);

	sqe = io_uring_get_sqe(ring);

	io_uring_prep_nop(sqe);

	io_uring_sqe_set_data(sqe, (void *) 1);

	msec_to_ts(&ts, 1000);

	i = 0;

	do {

		ret = io_uring_wait_cqes(ring, &cqe, 2, &ts, NULL);

		if (ret == -ETIME)

			break;

		if (ret < 0) {

			fprintf(stderr, "%s: wait timeout failed: %d\n", __FUNCTION__, ret);

			goto err;

		}

		ret = cqe->res;

		io_uring_cqe_seen(ring, cqe);

		if (ret < 0) {

			fprintf(stderr, "res: %d\n", ret);

			goto err;

		}

		i++;

	} while (1);

	if (i != 2) {

		fprintf(stderr, "got %d completions\n", i);

		goto err;

	}

	return 0;

err:

	return 1;

}

/*

 * Test single timeout waking us up

 */

static int test_single_timeout(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	unsigned long long exp;

	struct __kernel_timespec ts;

	struct timeval tv;

	int ret;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, TIMEOUT_MSEC);

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	gettimeofday(&tv, NULL);

	ret = io_uring_wait_cqe(ring, &cqe);

	if (ret < 0) {

		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

		goto err;

	}

	ret = cqe->res;

	io_uring_cqe_seen(ring, cqe);

	if (ret == -EINVAL) {

		fprintf(stdout, "%s: Timeout not supported, ignored\n", __FUNCTION__);

		not_supported = 1;

		return 0;

	} else if (ret != -ETIME) {

		fprintf(stderr, "%s: Timeout: %s\n", __FUNCTION__, strerror(-ret));

		goto err;

	}

	exp = mtime_since_now(&tv;;

	if (exp >= TIMEOUT_MSEC / 2 && exp <= (TIMEOUT_MSEC * 3) / 2)

		return 0;

	fprintf(stderr, "%s: Timeout seems wonky (got %llu)\n", __FUNCTION__, exp);

err:

	return 1;

}

static int test_single_timeout_remove_notfound(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	struct __kernel_timespec ts;

	int ret, i;

	if (no_modify)

		return 0;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, TIMEOUT_MSEC);

	io_uring_prep_timeout(sqe, &ts, 2, 0);

	sqe->user_data = 1;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout_remove(sqe, 2, 0);

	sqe->user_data = 2;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	/*

	 * We should get two completions. One is our modify request, which should

	 * complete with -ENOENT. The other is the timeout that will trigger after

	 * TIMEOUT_MSEC.

	 */

	for (i = 0; i < 2; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		if (cqe->user_data == 2) {

			if (cqe->res != -ENOENT) {

				fprintf(stderr, "%s: modify ret %d, wanted ENOENT\n", __FUNCTION__, cqe->res);

				break;

			}

		} else if (cqe->user_data == 1) {

			if (cqe->res != -ETIME) {

				fprintf(stderr, "%s: timeout ret %d, wanted -ETIME\n", __FUNCTION__, cqe->res);

				break;

			}

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;

}

static int test_single_timeout_remove(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	struct __kernel_timespec ts;

	int ret, i;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, TIMEOUT_MSEC);

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 1;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout_remove(sqe, 1, 0);

	sqe->user_data = 2;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	/*

	 * We should have two completions ready. One is for the original timeout

	 * request, user_data == 1, that should have a ret of -ECANCELED. The other

	 * is for our modify request, user_data == 2, that should have a ret of 0.

	 */

	for (i = 0; i < 2; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		if (no_modify)

			goto seen;

		if (cqe->res == -EINVAL && cqe->user_data == 2) {

			fprintf(stdout, "Timeout modify not supported, ignoring\n");

			no_modify = 1;

			goto seen;

		}

		if (cqe->user_data == 1) {

			if (cqe->res != -ECANCELED) {

				fprintf(stderr, "%s: timeout ret %d, wanted canceled\n", __FUNCTION__, cqe->res);

				break;

			}

		} else if (cqe->user_data == 2) {

			if (cqe->res) {

				fprintf(stderr, "%s: modify ret %d, wanted 0\n", __FUNCTION__, cqe->res);

				break;

			}

		}

seen:

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;

}

/*

 * Test single absolute timeout waking us up

 */

static int test_single_timeout_abs(struct io_uring *ring)

{

	struct io_uring_cqe *cqe;

	struct io_uring_sqe *sqe;

	unsigned long long exp;

	struct __kernel_timespec ts;

	struct timespec abs_ts;

	struct timeval tv;

	int ret;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	clock_gettime(CLOCK_MONOTONIC, &abs_ts);

	ts.tv_sec = abs_ts.tv_sec + 1;

	ts.tv_nsec = abs_ts.tv_nsec;

	io_uring_prep_timeout(sqe, &ts, 0, IORING_TIMEOUT_ABS);

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	gettimeofday(&tv, NULL);

	ret = io_uring_wait_cqe(ring, &cqe);

	if (ret < 0) {

		fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

		goto err;

	}

	ret = cqe->res;

	io_uring_cqe_seen(ring, cqe);

	if (ret == -EINVAL) {

		fprintf(stdout, "Absolute timeouts not supported, ignored\n");

		return 0;

	} else if (ret != -ETIME) {

		fprintf(stderr, "Timeout: %s\n", strerror(-ret));

		goto err;

	}

	exp = mtime_since_now(&tv;;

	if (exp >= 1000 / 2 && exp <= (1000 * 3) / 2)

		return 0;

	fprintf(stderr, "%s: Timeout seems wonky (got %llu)\n", __FUNCTION__, exp);

err:

	return 1;

}

/*

 * Test that timeout is canceled on exit

 */

static int test_single_timeout_exit(struct io_uring *ring)

{

	struct io_uring_sqe *sqe;

	struct __kernel_timespec ts;

	int ret;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	msec_to_ts(&ts, 30000);

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	io_uring_queue_exit(ring);

	return 0;

err:

	io_uring_queue_exit(ring);

	return 1;

}

/*

 * Test multi timeouts waking us up

 */

static int test_multi_timeout(struct io_uring *ring)

{

	struct io_uring_sqe *sqe;

	struct io_uring_cqe *cqe;

	struct __kernel_timespec ts[2];

	unsigned int timeout[2];

	unsigned long long exp;

	struct timeval tv;

	int ret, i;

	/* req_1: timeout req, count = 1, time = (TIMEOUT_MSEC * 2) */

	timeout[0] = TIMEOUT_MSEC * 2;

	msec_to_ts(&ts[0], timeout[0]);

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts[0], 1, 0);

	sqe->user_data = 1;

	/* req_2: timeout req, count = 1, time = TIMEOUT_MSEC */

	timeout[1] = TIMEOUT_MSEC;

	msec_to_ts(&ts[1], timeout[1]);

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts[1], 1, 0);

	sqe->user_data = 2;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	gettimeofday(&tv, NULL);

	for (i = 0; i < 2; i++) {

		unsigned int time;

		__u64 user_data;

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		/*

		 * Both of these two reqs should timeout, but req_2 should

		 * return before req_1.

		 */

		switch (i) {

		case 0:

			user_data = 2;

			time = timeout[1];

			break;

		case 1:

			user_data = 1;

			time = timeout[0];

			break;

		}

		if (cqe->user_data != user_data) {

			fprintf(stderr, "%s: unexpected timeout req %d sequece\n",

				__FUNCTION__, i+1);

			goto err;

		}

		if (cqe->res != -ETIME) {

			fprintf(stderr, "%s: Req %d timeout: %s\n",

				__FUNCTION__, i+1, strerror(cqe->res));

			goto err;

		}

		exp = mtime_since_now(&tv;;

		if (exp < time / 2 || exp > (time * 3) / 2) {

			fprintf(stderr, "%s: Req %d timeout seems wonky (got %llu)\n",

				__FUNCTION__, i+1, exp);

			goto err;

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;

}

/*

 * Test multi timeout req with different count

 */

static int test_multi_timeout_nr(struct io_uring *ring)

{

	struct io_uring_sqe *sqe;

	struct io_uring_cqe *cqe;

	struct __kernel_timespec ts;

	int ret, i;

	msec_to_ts(&ts, TIMEOUT_MSEC);

	/* req_1: timeout req, count = 2 */

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 2, 0);

	sqe->user_data = 1;

	/* req_2: timeout req, count = 1 */

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 1, 0);

	sqe->user_data = 2;

	/* req_3: nop req */

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_nop(sqe);

	io_uring_sqe_set_data(sqe, (void *) 1);

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	/*

	 * req_2 (count=1) should return without error and req_1 (count=2)

	 * should timeout.

	 */

	for (i = 0; i < 3; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		switch (i) {

		case 0:

			/* Should be nop req */

			if (io_uring_cqe_get_data(cqe) != (void *) 1) {

				fprintf(stderr, "%s: nop not seen as 1 or 2\n", __FUNCTION__);

				goto err;

			}

			break;

		case 1:

			/* Should be timeout req_2 */

			if (cqe->user_data != 2) {

				fprintf(stderr, "%s: unexpected timeout req %d sequece\n",

					__FUNCTION__, i+1);

				goto err;

			}

			if (cqe->res < 0) {

				fprintf(stderr, "%s: Req %d res %d\n",

					__FUNCTION__, i+1, cqe->res);

				goto err;

			}

			break;

		case 2:

			/* Should be timeout req_1 */

			if (cqe->user_data != 1) {

				fprintf(stderr, "%s: unexpected timeout req %d sequece\n",

					__FUNCTION__, i+1);

				goto err;

			}

			if (cqe->res != -ETIME) {

				fprintf(stderr, "%s: Req %d timeout: %s\n",

					__FUNCTION__, i+1, strerror(cqe->res));

				goto err;

			}

			break;

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;

}

/*

 * Test timeout <link> timeout <drain> timeout

 */

static int test_timeout_flags1(struct io_uring *ring)

{

	struct io_uring_sqe *sqe;

	struct io_uring_cqe *cqe;

	struct __kernel_timespec ts;

	int ret, i;

	msec_to_ts(&ts, TIMEOUT_MSEC);

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 1;

	sqe->flags |= IOSQE_IO_LINK;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 2;

	sqe->flags |= IOSQE_IO_DRAIN;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 3;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	for (i = 0; i < 3; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		if (cqe->res == -EINVAL) {

			if (!i)

				fprintf(stdout, "%s: timeout flags not supported\n",

						__FUNCTION__);

			io_uring_cqe_seen(ring, cqe);

			continue;

		}

		switch (cqe->user_data) {

		case 1:

			if (cqe->res != -ETIME) {

				fprintf(stderr, "%s: got %d, wanted %d\n",

						__FUNCTION__, cqe->res, -ETIME);

				goto err;

			}

			break;

		case 2:

			if (cqe->res != -ECANCELED) {

				fprintf(stderr, "%s: got %d, wanted %d\n",

						__FUNCTION__, cqe->res,

						-ECANCELED);

				goto err;

			}

			break;

		case 3:

			if (cqe->res != -ETIME) {

				fprintf(stderr, "%s: got %d, wanted %d\n",

						__FUNCTION__, cqe->res, -ETIME);

				goto err;

			}

			break;

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;

}

/*

 * Test timeout <link> timeout <link> timeout

 */

static int test_timeout_flags2(struct io_uring *ring)

{

	struct io_uring_sqe *sqe;

	struct io_uring_cqe *cqe;

	struct __kernel_timespec ts;

	int ret, i;

	msec_to_ts(&ts, TIMEOUT_MSEC);

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 1;

	sqe->flags |= IOSQE_IO_LINK;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 2;

	sqe->flags |= IOSQE_IO_LINK;

	sqe = io_uring_get_sqe(ring);

	if (!sqe) {

		fprintf(stderr, "%s: get sqe failed\n", __FUNCTION__);

		goto err;

	}

	io_uring_prep_timeout(sqe, &ts, 0, 0);

	sqe->user_data = 3;

	ret = io_uring_submit(ring);

	if (ret <= 0) {

		fprintf(stderr, "%s: sqe submit failed: %d\n", __FUNCTION__, ret);

		goto err;

	}

	for (i = 0; i < 3; i++) {

		ret = io_uring_wait_cqe(ring, &cqe);

		if (ret < 0) {

			fprintf(stderr, "%s: wait completion %d\n", __FUNCTION__, ret);

			goto err;

		}

		if (cqe->res == -EINVAL) {

			if (!i)

				fprintf(stdout, "%s: timeout flags not supported\n",

						__FUNCTION__);

			io_uring_cqe_seen(ring, cqe);

			continue;

		}

		switch (cqe->user_data) {

		case 1:

			if (cqe->res != -ETIME) {

				fprintf(stderr, "%s: got %d, wanted %d\n",

						__FUNCTION__, cqe->res, -ETIME);

				goto err;

			}

			break;

		case 2:

		case 3:

			if (cqe->res != -ECANCELED) {

				fprintf(stderr, "%s: got %d, wanted %d\n",

						__FUNCTION__, cqe->res,

						-ECANCELED);

				goto err;

			}

			break;

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return 0;

err:

	return 1;