#include <sys/types.h>
#include <sys/stat.h>
#include <sys/uio.h>
#include <fcntl.h>
#include <stdint.h>
#include <unistd.h>
#include <libaio.h>
#include <stdlib.h>
#include <stdio.h>

#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

const char usage[] = "Usage: test_aio [filename]";

int main(int argc, char *argv[])
{
	int res, i;
	struct timespec tspec;

	uint64_t data = 0xa5a5a5a5a5a5a5a5ULL;

	unsigned int iocbs_num = 1;

	struct iocb iocb_i[iocbs_num];
	struct iocb *iocbs[iocbs_num];
	struct io_event events[iocbs_num];
	io_context_t io_ctx;

	int fd;

	if (argc < 2) {
		fputs(usage, stderr);
		exit(1);
	}

	for (i = 0; i < iocbs_num; i++)
		iocbs[i] = &iocb_i[i];

	fd = open(argv[1], O_RDWR | O_SYNC);

	if (fd < 0) {
		perror("open");
		exit(1);
	}

	res = io_queue_init(iocbs_num, &io_ctx);

	if (res != 0) {
		fprintf(stderr, strerror(-res));
		exit(1);
	}

	int num_io = 1;

	io_prep_pread(iocbs[0], fd, &data, sizeof(data), 0);

	res = io_submit(io_ctx, num_io, iocbs);

	if (res != num_io) {
		fprintf(stderr, strerror(-res));
		exit(1);
	}

	res = io_cancel(io_ctx, iocbs[0], &events[0]);

	printf("io_cancel: res = %d\n", res);

	printf("events[0].res = %lu\n", events[0].res);
	printf("events[0].res2 = %lu\n", events[0].res2);

	tspec.tv_nsec = 0;
	tspec.tv_sec = 1;

	res = io_getevents(io_ctx, num_io, num_io, events, &tspec);

	printf("io_getevents: %d", res);

	io_queue_release(io_ctx);

	close(fd);
}