/* SPDX-License-Identifier: MIT */

/*

 * Description: test massive amounts of poll with cancel

 *

 */

#include <errno.h>

#include <stdio.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <inttypes.h>

#include <sys/poll.h>

#include <sys/wait.h>

#include <sys/signal.h>

#include "liburing.h"

#define POLL_COUNT	30000

static void *sqe_index[POLL_COUNT];

static int reap_events(struct io_uring *ring, unsigned nr_events, int nowait)

{

	struct io_uring_cqe *cqe;

	int i, ret = 0;

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

		if (!i && !nowait)

			ret = io_uring_wait_cqe(ring, &cqe);

		else

			ret = io_uring_peek_cqe(ring, &cqe);

		if (ret) {

			if (ret != -EAGAIN)

				fprintf(stderr, "cqe peek failed: %d\n", ret);

			break;

		}

		io_uring_cqe_seen(ring, cqe);

	}

	return i ? i : ret;

}

static int del_polls(struct io_uring *ring, int fd, int nr)

{

	int batch, i, ret;

	struct io_uring_sqe *sqe;

	while (nr) {

		batch = 1024;

		if (batch > nr)

			batch = nr;

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

			void *data;

			sqe = io_uring_get_sqe(ring);

			data = sqe_index[lrand48() % nr];

			io_uring_prep_poll_remove(sqe, data);

		}

		ret = io_uring_submit(ring);

		if (ret != batch) {

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

			return 1;

		}

		nr -= batch;

		ret = reap_events(ring, 2 * batch, 0);

	}

	return 0;

}

static int add_polls(struct io_uring *ring, int fd, int nr)

{

	int pending, batch, i, count, ret;

	struct io_uring_sqe *sqe;

	pending = count = 0;

	while (nr) {

		batch = 1024;

		if (batch > nr)

			batch = nr;

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

			sqe = io_uring_get_sqe(ring);

			io_uring_prep_poll_add(sqe, fd, POLLIN);

			sqe_index[count++] = sqe;

			sqe->user_data = (unsigned long) sqe;

		}

		ret = io_uring_submit(ring);

		if (ret != batch) {

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

			return 1;

		}

		nr -= batch;

		pending += batch;

		reap_events(ring, batch, 1);

	}

	return 0;

}

int main(int argc, char *argv[])

{

	struct io_uring ring;

	int pipe1[2];

	int ret;

	if (argc > 1)

		return 0;

	if (pipe(pipe1) != 0) {

		perror("pipe");

		return 1;

	}

	ret = io_uring_queue_init(1024, &ring, 0);

	if (ret) {

		fprintf(stderr, "ring setup failed: %d\n", ret);

		return 1;

	}

	add_polls(&ring, pipe1[0], 30000);

#if 0

	usleep(1000);

#endif

	del_polls(&ring, pipe1[0], 30000);

	io_uring_queue_exit(&ring);

	return 0;

}