#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <libaio.h>

int main(void)
{
	struct timespec ts;
#define NR_EVENTS	1024
	io_context_t ctx = 0UL;
	struct iocb iocb;
	struct iocb *iocbs[1] = { &iocb };
	struct io_event event;
	char buf[256];
	int fds[2];
	long ret;

	ret = io_setup(NR_EVENTS, &ctx);
	if (ret) {
		printf("io_setup() failed: %s\n", strerror(-ret));
		return 1;
	}

	ret = pipe(fds);
	if (ret) {
		perror("pipe() failed:");
		return 1;
	}

	io_prep_pread(&iocb, fds[0], buf, sizeof(buf), 0LL);
	ret = io_submit(ctx, 1, iocbs);
	if (ret <= 0) {
		printf("io_submit() failed: %s\n", strerror(-ret));
		return 1;
	}

#if 0
	ts.tv_sec = 1;
	ts.tv_nsec = 0;
	ret = io_getevents(ctx, 1, 1, &event, &ts);
	printf("io_getevents() = %ld: %s\n", ret, strerror(ret < 0 ? -ret : 0));
#endif

	ret = io_cancel(ctx, &iocb, &event);
	if (ret == -EINPROGRESS)
		printf("io_cancel() success: EINPROGRESS\n");
	else if (ret < 0) {
		printf("io_cancel() failed: %s\n", strerror(-ret));
		return 1;
	}

	if (!ret) {
		printf("io_cancel() = 0 - success!\n");
		printf("event.res = %ld\n", (long)event.res);
		printf("event.res2 = %ld\n", (long)event.res2);
		return 0;
	}

	ts.tv_sec = 1;
	ts.tv_nsec = 0;
	ret = io_getevents(ctx, 1, 1, &event, &ts);
	if (ret <= 0) {
		printf("io_getevents() = %ld: %s\n", ret, strerror(-ret));
		return 1;
	}
	if (ret != 1) {
		printf("io_getevents() = %ld: error != 1!\n", ret);
		return 1;
	}

	printf("event.res = %ld : %s\n", (long)event.res,
		(long)event.res < 0 ? strerror(-(long)event.res) : "success!");
	printf("event.res2 = %ld\n", (long)event.res2);
	if (event.res == -EINTR)
		printf("Test passed!\n");
	else
		printf("Test failed!  Unexpected result in event.res (should be %d).\n", -EINTR);
	return 0;
}