text: /* SPDX-License-Identifier: MIT */
  /*
   * Test that we exit properly with SQPOLL and having a request that
   * adds a circular reference to the ring itself.
   */
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <sys/time.h>
  #include <poll.h>
  #include "liburing.h"
  
  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);
  }
  
  int main(int argc, char *argv[])
  {
  	struct io_uring_params p = {};
  	struct timeval tv;
  	struct io_uring ring;
  	struct io_uring_sqe *sqe;
  	int ret;
  
  	if (argc > 1)
  		return 0;
  
  	p.flags = IORING_SETUP_SQPOLL;
  	p.sq_thread_idle = 100;
  
  	ret = io_uring_queue_init_params(1, &ring, &p);
  	if (ret) {
  		if (geteuid()) {
  			printf("%s: skipped, not root\n", argv[0]);
  			return 0;
  		}
  		fprintf(stderr, "queue_init=%d\n", ret);
  		return 1;
  	}
  
  	if (!(p.features & IORING_FEAT_SQPOLL_NONFIXED)) {
  		fprintf(stdout, "Skipping\n");
  		return 0;
  	}
  
  	sqe = io_uring_get_sqe(&ring);
  	io_uring_prep_poll_add(sqe, ring.ring_fd, POLLIN);
  	io_uring_submit(&ring);
  
  	gettimeofday(&tv, NULL);
  	do {
  		usleep(1000);
  	} while (mtime_since_now(&tv) < 1000);
  
  	return 0;
  }
  