/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2024 Gleb Smirnoff <glebius@FreeBSD.org>
 * Copyright (c) 2018 Rozhuk Ivan <rozhuk.im@gmail.com>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <sys/select.h>
#include <sys/event.h>
#include <poll.h>

#include <stdbool.h>
#include <unistd.h>
#include <time.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <pthread_np.h>

#include <atf-c.h>

/*
 * This test runs several scenarios when sleep(9) on a listen(2)ing socket is
 * interrupted by shutdown(2) or by close(2).  What should happen in that case
 * is not specified, neither is documented.  However, there is certain behavior
 * that we have and this test makes sure it is preserved.  The known software
 * to rely on the behavior is FreeSWITCH telephony software (see bug 227259).
 * There might be more. This test is based on submission with the bug, bugzilla
 * attachment 192260.
 */

static const struct test {
        enum {
                SLEEP_ACCEPT = 0,
                SLEEP_SELECT,
                SLEEP_POLL,
                SLEEP_KQUEUE,
                NSLEEP
        }               sleep;
        enum {
                WAKEUP_SHUTDOWN,
                WAKEUP_CLOSE,
        }               wakeup;
        enum {
                AFTER,
                BEFORE,
        }               when;
        bool            nonblock;
        int             result;
} tests[] = {
        { SLEEP_ACCEPT, WAKEUP_SHUTDOWN, AFTER, false,  ECONNABORTED },
        { SLEEP_SELECT, WAKEUP_SHUTDOWN, AFTER, false,  0 },
        { SLEEP_POLL,   WAKEUP_SHUTDOWN, AFTER, false,  0 },
        { SLEEP_KQUEUE, WAKEUP_SHUTDOWN, AFTER, false,  0 },
        { SLEEP_ACCEPT, WAKEUP_CLOSE,    AFTER, false,  ETIMEDOUT },
        { SLEEP_SELECT, WAKEUP_CLOSE,    AFTER, false,  EBADF },
        { SLEEP_POLL,   WAKEUP_CLOSE,    AFTER, false,  0 },
        { SLEEP_KQUEUE, WAKEUP_CLOSE,    AFTER, false,  0 },
        { SLEEP_ACCEPT, WAKEUP_SHUTDOWN, BEFORE, false, ECONNABORTED },
        { SLEEP_SELECT, WAKEUP_SHUTDOWN, BEFORE, false, 0 },
        { SLEEP_POLL,   WAKEUP_SHUTDOWN, BEFORE, false, 0 },
        { SLEEP_KQUEUE, WAKEUP_SHUTDOWN, BEFORE, false, 0 },
        { SLEEP_SELECT, WAKEUP_SHUTDOWN, AFTER, true,   0 },
        { SLEEP_POLL,   WAKEUP_SHUTDOWN, AFTER, true,   0 },
        { SLEEP_KQUEUE, WAKEUP_SHUTDOWN, AFTER, true,   0 },
        { SLEEP_SELECT, WAKEUP_SHUTDOWN, BEFORE, true,  0 },
        { SLEEP_POLL,   WAKEUP_SHUTDOWN, BEFORE, true,  0 },
        { SLEEP_KQUEUE, WAKEUP_SHUTDOWN, BEFORE, true,  0 },
};

static int
tcp_listen(void)
{
        struct sockaddr_in sin = {
                .sin_family = PF_INET,
                .sin_len = sizeof(sin),
        };
        int s;

        ATF_REQUIRE((s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) != -1);
        ATF_REQUIRE(bind(s, (struct sockaddr *)&sin, sizeof(sin)) == 0);
        ATF_REQUIRE(listen(s, -1) == 0);

        return (s);
}

static int
unix_listen(void)
{
        struct sockaddr_un sun = {
                .sun_family = AF_UNIX,
                .sun_len = sizeof(sun),
                .sun_path = "listen-shutdown-test.sock",
        };
        int s;

        ATF_REQUIRE((s = socket(PF_UNIX, SOCK_STREAM, 0)) != -1);
        (void)unlink(sun.sun_path);
        ATF_REQUIRE(bind(s, (struct sockaddr *)&sun, sizeof(sun)) == 0);
        ATF_REQUIRE(listen(s, -1) == 0);

        return (s);
}

static const struct proto {
        const char *name;
        int (*listen)(void);
} protos[] = {
        { "PF_INET", tcp_listen },
        { "PF_UNIX", unix_listen },
};

static int
sleep_accept(int s)
{
        int rv;

        rv = accept(s, NULL, NULL);

        return (rv == -1 ? errno : 0);
}

static int
sleep_select(int s)
{
        fd_set fds;
        int rv;

        FD_ZERO(&fds);
        FD_SET(s, &fds);
        rv = select(s + 1, &fds, &fds, &fds, NULL);

        return (rv == -1 ? errno : 0);
}

static int
sleep_poll(int s)
{
        struct pollfd fds = {
                .fd = s,
                .events = (POLLIN | POLLPRI | POLLRDNORM | POLLWRNORM |
                           POLLRDBAND | POLLWRBAND),
                .revents = 0,
        };
        int rv;

        rv = poll(&fds, 1, INFTIM);

        return (rv == -1 ? errno : 0);
}

static int
sleep_kqueue(int s)
{
        struct kevent kev;
        int kq, error;

        ATF_REQUIRE((kq = kqueue()) != -1);
        EV_SET(&kev, s, EVFILT_READ, EV_ADD, 0, 0, NULL);
        if (kevent(kq, &kev, 1, NULL, 0, NULL) == -1) {
                error = errno;
        } else {
                if (kev.flags & EV_ERROR)
                        error = (int)kev.data;
                else
                        error = 0;
        }
        ATF_REQUIRE(close(kq) == 0);

        return (error);
}

typedef int sleep_syscall_t(int);
static sleep_syscall_t *sleep_syscalls[NSLEEP] = {
        [SLEEP_ACCEPT] = sleep_accept,
        [SLEEP_SELECT] = sleep_select,
        [SLEEP_POLL] = sleep_poll,
        [SLEEP_KQUEUE] = sleep_kqueue,
};

struct test_ctx {
        struct test const *test;
        int s;
        int result;
};

static void *
sleep_syscall_thread(void *data) {
        struct test_ctx *ctx = data;

        ctx->result = sleep_syscalls[ctx->test->sleep](ctx->s);

        return (NULL);
}

static void
run_tests(const struct proto *pr)
{
        pthread_t tid;
        struct timespec ts;
        int error;

        for (u_int i = 0; i < nitems(tests); i ++) {
                struct test const *t = &tests[i];
                struct test_ctx ctx = {
                        .test = t,
                        /* Note: tested syscalls don't return this. */
                        .result = ETIMEDOUT,
                };

                ctx.s = pr->listen();
                if (t->nonblock)
                        ATF_REQUIRE(fcntl(ctx.s, F_SETFL, O_NONBLOCK) != -1);

                if (t->when == AFTER) {
                        ATF_REQUIRE(pthread_create(&tid, NULL,
                            sleep_syscall_thread, &ctx) == 0);
                        usleep(100000);
                }

                switch (t->wakeup) {
                case WAKEUP_SHUTDOWN:
                        ATF_REQUIRE(shutdown(ctx.s, SHUT_RDWR) == -1);
                        ATF_REQUIRE(errno == ENOTCONN);
                        break;
                case WAKEUP_CLOSE:
                        ATF_REQUIRE(close(ctx.s) == 0);
                        break;
                }

                if (t->when == BEFORE) {
                        ATF_REQUIRE(pthread_create(&tid, NULL,
                            sleep_syscall_thread, &ctx) == 0);
                        usleep(100000);
                }

                clock_gettime(CLOCK_REALTIME, &ts);
                ts.tv_sec++;
                if ((error = pthread_timedjoin_np(tid, NULL, &ts)) != 0) {
                        ATF_REQUIRE(pthread_cancel(tid) == 0);
                        ATF_REQUIRE(error == ETIMEDOUT);
                        ATF_REQUIRE(ctx.result == ETIMEDOUT);
                }

                ATF_REQUIRE_MSG(ctx.result == t->result,
                    "proto %s sleeping syscall #%d wakeup #%d nb %d, "
                    "expected %d, got %d", pr->name, t->sleep, t->wakeup,
                    t->nonblock, t->result, ctx.result);

                if (t->wakeup == WAKEUP_SHUTDOWN)
                        ATF_REQUIRE(close(ctx.s) == 0);
        }
}

ATF_TC_WITHOUT_HEAD(all);
ATF_TC_BODY(all, tc)
{
        for (u_int f = 0; f < nitems(protos); f++)
                run_tests(&protos[f]);
}

ATF_TP_ADD_TCS(tp)
{
        ATF_TP_ADD_TC(tp, all);

        return (atf_no_error());
}