/*      $OpenBSD: kqueue-user.c,v 1.2 2025/05/21 14:10:16 visa Exp $    */

/*
 * Copyright (c) 2022 Visa Hankala
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/event.h>

#include <err.h>
#include <errno.h>
#include <unistd.h>

#include "main.h"

int
do_user(void)
{
        const struct timespec ts = { 0, 10000 };
        struct kevent kev[2];
        int dummy, dummy2, i, kq, n;

        ASS((kq = kqueue()) >= 0,
            warn("kqueue"));

        /* Set up an event. */
        EV_SET(&kev[0], 1, EVFILT_USER, EV_ADD, ~0U & ~NOTE_TRIGGER, 0, NULL);
        ASS(kevent(kq, kev, 1, NULL, 0, NULL) == 0,
            warn("kevent"));

        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 0);

        /* Activate the event. This updates `data' and `udata'. */
        EV_SET(&kev[0], 1, EVFILT_USER, 0, NOTE_TRIGGER | NOTE_FFNOP,
            123, &dummy);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        /* Check active events. */
        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 1);
        ASSX(kev[0].ident == 1);
        ASSX(kev[0].fflags == NOTE_FFLAGSMASK);
        ASSX(kev[0].data == 123);
        ASSX(kev[0].udata == &dummy);

        /* Set up another event. */
        EV_SET(&kev[0], 2, EVFILT_USER, EV_ADD, NOTE_TRIGGER, 654, &dummy2);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        /* Check active events. This assumes a specific output order. */
        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 2);
        ASSX(kev[0].ident == 1);
        ASSX(kev[0].fflags == NOTE_FFLAGSMASK);
        ASSX(kev[0].data == 123);
        ASSX(kev[0].udata == &dummy);
        ASSX(kev[1].ident == 2);
        ASSX(kev[1].fflags == 0);
        ASSX(kev[1].data == 654);
        ASSX(kev[1].udata == &dummy2);

        /* Clear the first event. */
        EV_SET(&kev[0], 1, EVFILT_USER, EV_CLEAR, 0, 0, NULL);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 1);
        ASSX(kev[0].ident == 2);
        ASSX(kev[0].fflags == 0);
        ASSX(kev[0].data == 654);
        ASSX(kev[0].udata == &dummy2);

        /* Delete the second event. */
        EV_SET(&kev[0], 2, EVFILT_USER, EV_DELETE, 0, 0, NULL);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 0);

        /* Test self-clearing event. */
        EV_SET(&kev[0], 2, EVFILT_USER, EV_ADD | EV_CLEAR, 0x11, 42, &dummy);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 0);

        EV_SET(&kev[0], 2, EVFILT_USER, 0, NOTE_TRIGGER | 0x3, 24, &dummy2);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 1);
        ASSX(kev[0].ident == 2);
        ASSX(kev[0].fflags == 0x11);
        ASSX(kev[0].data == 24);
        ASSX(kev[0].udata == &dummy2);

        n = kevent(kq, NULL, 0, kev, 2, &ts);
        ASSX(n == 0);

        EV_SET(&kev[0], 2, EVFILT_USER, 0, NOTE_TRIGGER | 0x3, 9, &dummy2);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 1);
        ASSX(kev[0].ident == 2);
        ASSX(kev[0].fflags == 0x11);
        ASSX(kev[0].data == 9);
        ASSX(kev[0].udata == &dummy2);

        EV_SET(&kev[0], 2, EVFILT_USER, EV_DELETE, 0, 0, NULL);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 0);

        /* Change fflags. */
        EV_SET(&kev[0], 1, EVFILT_USER, 0, NOTE_FFCOPY | 0x00aa00, 0, NULL);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 0);
        EV_SET(&kev[0], 1, EVFILT_USER, 0, NOTE_FFOR | 0xff00ff, 0, NULL);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 0);
        EV_SET(&kev[0], 1, EVFILT_USER, 0, NOTE_TRIGGER | NOTE_FFAND | 0x0ffff0,
            0, NULL);
        n = kevent(kq, kev, 1, kev, 2, &ts);
        ASSX(n == 1);
        ASSX(kev[0].ident == 1);
        ASSX(kev[0].fflags == 0x0faaf0);
        ASSX(kev[0].data == 0);
        ASSX(kev[0].udata == NULL);

        /* Test event limit. */
        for (i = 0;; i++) {
                EV_SET(&kev[0], i, EVFILT_USER, EV_ADD, 0, 0, NULL);
                n = kevent(kq, kev, 1, NULL, 0, NULL);
                if (n == -1) {
                        ASSX(errno == ENOMEM);
                        break;
                }
                ASSX(n == 0);
        }
        ASSX(i < 1000000);

        /* Delete one event, ... */
        EV_SET(&kev[0], 0, EVFILT_USER, EV_DELETE, 0, 0, NULL);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        /* ... after which adding should succeed. */
        EV_SET(&kev[0], 0, EVFILT_USER, EV_ADD, 0, 0, NULL);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == 0);

        EV_SET(&kev[0], i, EVFILT_USER, EV_ADD, 0, 0, NULL);
        n = kevent(kq, kev, 1, NULL, 0, NULL);
        ASSX(n == -1);
        ASSX(errno == ENOMEM);

        close(kq);

        return (0);
}