/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2008 Yahoo!, Inc.
 * All rights reserved.
 * Written by: John Baldwin <jhb@FreeBSD.org>
 *
 * 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.
 * 3. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * 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/queue.h>
#include <sys/_semaphore.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/user.h>
#include <sys/wait.h>

#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <semaphore.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "test.h"

#define TEST_PATH       "/tmp/posixsem_regression_test"

#define ELAPSED(elapsed, limit)         (abs((elapsed) - (limit)) < 100)

/* Macros for passing child status to parent over a pipe. */
#define CSTAT(class, error)             ((class) << 16 | (error))
#define CSTAT_CLASS(stat)               ((stat) >> 16)
#define CSTAT_ERROR(stat)               ((stat) & 0xffff)

/*
 * Helper routine for tests that use a child process.  This routine
 * creates a pipe and forks a child process.  The child process runs
 * the 'func' routine which returns a status integer.  The status
 * integer gets written over the pipe to the parent and returned in
 * '*stat'.  If there is an error in pipe(), fork(), or wait() this
 * returns -1 and fails the test.
 */
static int
child_worker(int (*func)(void *arg), void *arg, int *stat)
{
        pid_t pid;
        int pfd[2], cstat;

        if (pipe(pfd) < 0) {
                fail_errno("pipe");
                return (-1);
        }

        pid = fork();
        switch (pid) {
        case -1:
                /* Error. */
                fail_errno("fork");
                close(pfd[0]);
                close(pfd[1]);
                return (-1);
        case 0:
                /* Child. */
                cstat = func(arg);
                write(pfd[1], &cstat, sizeof(cstat));
                exit(0);
        }

        if (read(pfd[0], stat, sizeof(*stat)) < 0) {
                fail_errno("read(pipe)");
                close(pfd[0]);
                close(pfd[1]);
                return (-1);
        }
        if (waitpid(pid, NULL, 0) < 0) {
                fail_errno("wait");
                close(pfd[0]);
                close(pfd[1]);
                return (-1);
        }
        close(pfd[0]);
        close(pfd[1]);
        return (0);
}

/*
 * Attempt a ksem_open() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_open_should_fail(const char *path, int flags, mode_t mode, unsigned int
    value, int error)
{
        semid_t id;

        if (ksem_open(&id, path, flags, mode, value) >= 0) {
                fail_err("ksem_open() didn't fail");
                ksem_close(id);
                return;
        }
        if (errno != error) {
                fail_errno("ksem_open");
                return;
        }
        pass();
}

/*
 * Attempt a ksem_unlink() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_unlink_should_fail(const char *path, int error)
{

        if (ksem_unlink(path) >= 0) {
                fail_err("ksem_unlink() didn't fail");
                return;
        }
        if (errno != error) {
                fail_errno("ksem_unlink");
                return;
        }
        pass();
}

/*
 * Attempt a ksem_close() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_close_should_fail(semid_t id, int error)
{

        if (ksem_close(id) >= 0) {
                fail_err("ksem_close() didn't fail");
                return;
        }
        if (errno != error) {
                fail_errno("ksem_close");
                return;
        }
        pass();
}

/*
 * Attempt a ksem_init() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_init_should_fail(unsigned int value, int error)
{
        semid_t id;

        if (ksem_init(&id, value) >= 0) {
                fail_err("ksem_init() didn't fail");
                ksem_destroy(id);
                return;
        }
        if (errno != error) {
                fail_errno("ksem_init");
                return;
        }
        pass();
}

/*
 * Attempt a ksem_destroy() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_destroy_should_fail(semid_t id, int error)
{

        if (ksem_destroy(id) >= 0) {
                fail_err("ksem_destroy() didn't fail");
                return;
        }
        if (errno != error) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}

/*
 * Attempt a ksem_post() that should fail with an expected error of
 * 'error'.
 */
static void
ksem_post_should_fail(semid_t id, int error)
{

        if (ksem_post(id) >= 0) {
                fail_err("ksem_post() didn't fail");
                return;
        }
        if (errno != error) {
                fail_errno("ksem_post");
                return;
        }
        pass();
}

static void
open_after_unlink(void)
{
        semid_t id;

        if (ksem_open(&id, TEST_PATH, O_CREAT, 0777, 1) < 0) {
                fail_errno("ksem_open(1)");
                return;
        }
        ksem_close(id);

        if (ksem_unlink(TEST_PATH) < 0) {
                fail_errno("ksem_unlink");
                return;
        }

        ksem_open_should_fail(TEST_PATH, O_RDONLY, 0777, 1, ENOENT);
}
TEST(open_after_unlink, "open after unlink");

static void
open_invalid_path(void)
{

        ksem_open_should_fail("blah", 0, 0777, 1, EINVAL);
}
TEST(open_invalid_path, "open invalid path");

static void
open_extra_flags(void)
{

        ksem_open_should_fail(TEST_PATH, O_RDONLY | O_DIRECT, 0777, 1, EINVAL);
}
TEST(open_extra_flags, "open with extra flags");

static void
open_bad_value(void)
{

        (void)ksem_unlink(TEST_PATH);

        ksem_open_should_fail(TEST_PATH, O_CREAT, 0777, UINT_MAX, EINVAL);
}
TEST(open_bad_value, "open with invalid initial value");

static void
open_bad_path_pointer(void)
{

        ksem_open_should_fail((char *)1024, O_RDONLY, 0777, 1, EFAULT);
}
TEST(open_bad_path_pointer, "open bad path pointer");

static void
open_path_too_long(void)
{
        char *page;

        page = malloc(MAXPATHLEN + 1);
        memset(page, 'a', MAXPATHLEN);
        page[MAXPATHLEN] = '\0';
        ksem_open_should_fail(page, O_RDONLY, 0777, 1, ENAMETOOLONG);
        free(page);
}
TEST(open_path_too_long, "open pathname too long");

static void
open_nonexisting_semaphore(void)
{

        ksem_open_should_fail("/notreallythere", 0, 0777, 1, ENOENT);
}
TEST(open_nonexisting_semaphore, "open nonexistent semaphore");

static void
exclusive_create_existing_semaphore(void)
{
        semid_t id;

        if (ksem_open(&id, TEST_PATH, O_CREAT, 0777, 1) < 0) {
                fail_errno("ksem_open(O_CREAT)");
                return;
        }
        ksem_close(id);

        ksem_open_should_fail(TEST_PATH, O_CREAT | O_EXCL, 0777, 1, EEXIST);

        ksem_unlink(TEST_PATH);
}
TEST(exclusive_create_existing_semaphore, "O_EXCL of existing semaphore");

static void
init_bad_value(void)
{

        ksem_init_should_fail(UINT_MAX, EINVAL);
}
TEST(init_bad_value, "init with invalid initial value");

static void
unlink_bad_path_pointer(void)
{

        ksem_unlink_should_fail((char *)1024, EFAULT);
}
TEST(unlink_bad_path_pointer, "unlink bad path pointer");

static void
unlink_path_too_long(void)
{
        char *page;

        page = malloc(MAXPATHLEN + 1);
        memset(page, 'a', MAXPATHLEN);
        page[MAXPATHLEN] = '\0';
        ksem_unlink_should_fail(page, ENAMETOOLONG);
        free(page);
}
TEST(unlink_path_too_long, "unlink pathname too long");

static void
destroy_named_semaphore(void)
{
        semid_t id;

        if (ksem_open(&id, TEST_PATH, O_CREAT, 0777, 1) < 0) {
                fail_errno("ksem_open(O_CREAT)");
                return;
        }

        ksem_destroy_should_fail(id, EINVAL);

        ksem_close(id);
        ksem_unlink(TEST_PATH);
}
TEST(destroy_named_semaphore, "destroy named semaphore");

static void
close_unnamed_semaphore(void)
{
        semid_t id;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }

        ksem_close_should_fail(id, EINVAL);

        ksem_destroy(id);
}
TEST(close_unnamed_semaphore, "close unnamed semaphore");

static void
destroy_invalid_fd(void)
{

        ksem_destroy_should_fail(STDERR_FILENO, EINVAL);
}
TEST(destroy_invalid_fd, "destroy non-semaphore file descriptor");

static void
close_invalid_fd(void)
{

        ksem_close_should_fail(STDERR_FILENO, EINVAL);
}
TEST(close_invalid_fd, "close non-semaphore file descriptor");

static void
create_unnamed_semaphore(void)
{
        semid_t id;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(create_unnamed_semaphore, "create unnamed semaphore");

static void
open_named_semaphore(void)
{
        semid_t id;

        if (ksem_open(&id, TEST_PATH, O_CREAT, 0777, 1) < 0) {
                fail_errno("ksem_open(O_CREAT)");
                return;
        }

        if (ksem_close(id) < 0) {
                fail_errno("ksem_close");
                return;
        }

        if (ksem_unlink(TEST_PATH) < 0) {
                fail_errno("ksem_unlink");
                return;
        }
        pass();
}
TEST(open_named_semaphore, "create named semaphore");

static void
getvalue_invalid_semaphore(void)
{
        int val;

        if (ksem_getvalue(STDERR_FILENO, &val) >= 0) {
                fail_err("ksem_getvalue() didn't fail");
                return;
        }
        if (errno != EINVAL) {
                fail_errno("ksem_getvalue");
                return;
        }
        pass();
}
TEST(getvalue_invalid_semaphore, "get value of invalid semaphore");

static void
post_invalid_semaphore(void)
{

        ksem_post_should_fail(STDERR_FILENO, EINVAL);
}
TEST(post_invalid_semaphore, "post of invalid semaphore");

static void
wait_invalid_semaphore(void)
{

        if (ksem_wait(STDERR_FILENO) >= 0) {
                fail_err("ksem_wait() didn't fail");
                return;
        }
        if (errno != EINVAL) {
                fail_errno("ksem_wait");
                return;
        }
        pass();
}
TEST(wait_invalid_semaphore, "wait for invalid semaphore");

static void
trywait_invalid_semaphore(void)
{

        if (ksem_trywait(STDERR_FILENO) >= 0) {
                fail_err("ksem_trywait() didn't fail");
                return;
        }
        if (errno != EINVAL) {
                fail_errno("ksem_trywait");
                return;
        }
        pass();
}
TEST(trywait_invalid_semaphore, "try wait for invalid semaphore");

static void
timedwait_invalid_semaphore(void)
{

        if (ksem_timedwait(STDERR_FILENO, NULL) >= 0) {
                fail_err("ksem_timedwait() didn't fail");
                return;
        }
        if (errno != EINVAL) {
                fail_errno("ksem_timedwait");
                return;
        }
        pass();
}
TEST(timedwait_invalid_semaphore, "timed wait for invalid semaphore");

static int
checkvalue(semid_t id, int expected)
{
        int val;

        if (ksem_getvalue(id, &val) < 0) {
                fail_errno("ksem_getvalue");
                return (-1);
        }
        if (val != expected) {
                fail_err("sem value should be %d instead of %d", expected, val);
                return (-1);
        }
        return (0);
}

static void
post_test(void)
{
        semid_t id;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }
        if (checkvalue(id, 1) < 0) {
                ksem_destroy(id);
                return;
        }
        if (ksem_post(id) < 0) {
                fail_errno("ksem_post");
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 2) < 0) {
                ksem_destroy(id);
                return;
        }
        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(post_test, "simple post");

static void
use_after_unlink_test(void)
{
        semid_t id;

        /*
         * Create named semaphore with value of 1 and then unlink it
         * while still retaining the initial reference.
         */
        if (ksem_open(&id, TEST_PATH, O_CREAT | O_EXCL, 0777, 1) < 0) {
                fail_errno("ksem_open(O_CREAT | O_EXCL)");
                return;
        }
        if (ksem_unlink(TEST_PATH) < 0) {
                fail_errno("ksem_unlink");
                ksem_close(id);
                return;
        }
        if (checkvalue(id, 1) < 0) {
                ksem_close(id);
                return;
        }

        /* Post the semaphore to set its value to 2. */
        if (ksem_post(id) < 0) {
                fail_errno("ksem_post");
                ksem_close(id);
                return;
        }
        if (checkvalue(id, 2) < 0) {
                ksem_close(id);
                return;
        }

        /* Wait on the semaphore which should set its value to 1. */
        if (ksem_wait(id) < 0) {
                fail_errno("ksem_wait");
                ksem_close(id);
                return;
        }
        if (checkvalue(id, 1) < 0) {
                ksem_close(id);
                return;
        }

        if (ksem_close(id) < 0) {
                fail_errno("ksem_close");
                return;
        }
        pass();
}
TEST(use_after_unlink_test, "use named semaphore after unlink");

static void
unlocked_trywait(void)
{
        semid_t id;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /* This should succeed and decrement the value to 0. */
        if (ksem_trywait(id) < 0) {
                fail_errno("ksem_trywait()");
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(unlocked_trywait, "unlocked trywait");

static void
locked_trywait(void)
{
        semid_t id;

        if (ksem_init(&id, 0) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /* This should fail with EAGAIN and leave the value at 0. */
        if (ksem_trywait(id) >= 0) {
                fail_err("ksem_trywait() didn't fail");
                ksem_destroy(id);
                return;
        }
        if (errno != EAGAIN) {
                fail_errno("wrong error from ksem_trywait()");
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(locked_trywait, "locked trywait");

/*
 * Use a timer to post a specific semaphore after a timeout.  A timer
 * is scheduled via schedule_post().  check_alarm() must be called
 * afterwards to clean up and check for errors.
 */
static semid_t alarm_id = -1;
static int alarm_errno;
static int alarm_handler_installed;

static void
alarm_handler(int signo)
{

        if (ksem_post(alarm_id) < 0)
                alarm_errno = errno;
}

static int
check_alarm(int just_clear)
{
        struct itimerval it;

        bzero(&it, sizeof(it));
        if (just_clear) {
                setitimer(ITIMER_REAL, &it, NULL);
                alarm_errno = 0;
                alarm_id = -1;
                return (0);
        }
        if (setitimer(ITIMER_REAL, &it, NULL) < 0) {
                fail_errno("setitimer");
                return (-1);
        }
        if (alarm_errno != 0 && !just_clear) {
                errno = alarm_errno;
                fail_errno("ksem_post() (via timeout)");
                alarm_errno = 0;
                return (-1);
        }
        alarm_id = -1;
        
        return (0);
}

static int
schedule_post(semid_t id, u_int msec)
{
        struct itimerval it;

        if (!alarm_handler_installed) {
                if (signal(SIGALRM, alarm_handler) == SIG_ERR) {
                        fail_errno("signal(SIGALRM)");
                        return (-1);
                }
                alarm_handler_installed = 1;
        }
        if (alarm_id != -1) {
                fail_err("ksem_post() already scheduled");
                return (-1);
        }
        alarm_id = id;
        bzero(&it, sizeof(it));
        it.it_value.tv_sec = msec / 1000;
        it.it_value.tv_usec = (msec % 1000) * 1000;
        if (setitimer(ITIMER_REAL, &it, NULL) < 0) {
                fail_errno("setitimer");
                return (-1);
        }
        return (0);
}

static int
timedwait(semid_t id, u_int msec, u_int *delta, int error)
{
        struct timespec start, end;

        if (clock_gettime(CLOCK_REALTIME, &start) < 0) {
                fail_errno("clock_gettime(CLOCK_REALTIME)");
                return (-1);
        }
        end.tv_sec = msec / 1000;
        end.tv_nsec = msec % 1000 * 1000000;
        timespecadd(&end, &start, &end);
        if (ksem_timedwait(id, &end) < 0) {
                if (errno != error) {
                        fail_errno("ksem_timedwait");
                        return (-1);
                }
        } else if (error != 0) {
                fail_err("ksem_timedwait() didn't fail");
                return (-1);
        }
        if (clock_gettime(CLOCK_REALTIME, &end) < 0) {
                fail_errno("clock_gettime(CLOCK_REALTIME)");
                return (-1);
        }
        timespecsub(&end, &start, &end);
        *delta = end.tv_nsec / 1000000;
        *delta += end.tv_sec * 1000;
        return (0);
}

static void
unlocked_timedwait(void)
{
        semid_t id;
        u_int elapsed;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /* This should succeed right away and set the value to 0. */
        if (timedwait(id, 5000, &elapsed, 0) < 0) {
                ksem_destroy(id);
                return;
        }
        if (!ELAPSED(elapsed, 0)) {
                fail_err("ksem_timedwait() of unlocked sem took %ums", elapsed);
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(unlocked_timedwait, "unlocked timedwait");

static void
expired_timedwait(void)
{
        semid_t id;
        u_int elapsed;

        if (ksem_init(&id, 0) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /* This should fail with a timeout and leave the value at 0. */
        if (timedwait(id, 2500, &elapsed, ETIMEDOUT) < 0) {
                ksem_destroy(id);
                return;
        }
        if (!ELAPSED(elapsed, 2500)) {
                fail_err(
            "ksem_timedwait() of locked sem took %ums instead of 2500ms",
                    elapsed);
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(expired_timedwait, "locked timedwait timeout");

static void
locked_timedwait(void)
{
        semid_t id;
        u_int elapsed;

        if (ksem_init(&id, 0) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /*
         * Schedule a post to trigger after 1000 ms.  The subsequent
         * timedwait should succeed after 1000 ms as a result w/o
         * timing out.
         */
        if (schedule_post(id, 1000) < 0) {
                ksem_destroy(id);
                return;
        }
        if (timedwait(id, 2000, &elapsed, 0) < 0) {
                check_alarm(1);
                ksem_destroy(id);
                return;
        }
        if (!ELAPSED(elapsed, 1000)) {
                fail_err(
            "ksem_timedwait() with delayed post took %ums instead of 1000ms",
                    elapsed);
                check_alarm(1);
                ksem_destroy(id);
                return;
        }
        if (check_alarm(0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(locked_timedwait, "locked timedwait");

static int
testwait(semid_t id, u_int *delta)
{
        struct timespec start, end;

        if (clock_gettime(CLOCK_REALTIME, &start) < 0) {
                fail_errno("clock_gettime(CLOCK_REALTIME)");
                return (-1);
        }
        if (ksem_wait(id) < 0) {
                fail_errno("ksem_wait");
                return (-1);
        }
        if (clock_gettime(CLOCK_REALTIME, &end) < 0) {
                fail_errno("clock_gettime(CLOCK_REALTIME)");
                return (-1);
        }
        timespecsub(&end, &start, &end);
        *delta = end.tv_nsec / 1000000;
        *delta += end.tv_sec * 1000;
        return (0);
}

static void
unlocked_wait(void)
{
        semid_t id;
        u_int elapsed;

        if (ksem_init(&id, 1) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /* This should succeed right away and set the value to 0. */
        if (testwait(id, &elapsed) < 0) {
                ksem_destroy(id);
                return;
        }
        if (!ELAPSED(elapsed, 0)) {
                fail_err("ksem_wait() of unlocked sem took %ums", elapsed);
                ksem_destroy(id);
                return;
        }
        if (checkvalue(id, 0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(unlocked_wait, "unlocked wait");

static void
locked_wait(void)
{
        semid_t id;
        u_int elapsed;

        if (ksem_init(&id, 0) < 0) {
                fail_errno("ksem_init");
                return;
        }

        /*
         * Schedule a post to trigger after 1000 ms.  The subsequent
         * wait should succeed after 1000 ms as a result.
         */
        if (schedule_post(id, 1000) < 0) {
                ksem_destroy(id);
                return;
        }
        if (testwait(id, &elapsed) < 0) {
                check_alarm(1);
                ksem_destroy(id);
                return;
        }
        if (!ELAPSED(elapsed, 1000)) {
                fail_err(
            "ksem_wait() with delayed post took %ums instead of 1000ms",
                    elapsed);
                check_alarm(1);
                ksem_destroy(id);
                return;
        }
        if (check_alarm(0) < 0) {
                ksem_destroy(id);
                return;
        }

        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(locked_wait, "locked wait");

/*
 * Fork off a child process.  The child will open the semaphore via
 * the same name.  The child will then block on the semaphore waiting
 * for the parent to post it.
 */
static int
wait_twoproc_child(void *arg)
{
        semid_t id;

        if (ksem_open(&id, TEST_PATH, 0, 0, 0) < 0)
                return (CSTAT(1, errno));
        if (ksem_wait(id) < 0)
                return (CSTAT(2, errno));
        if (ksem_close(id) < 0)
                return (CSTAT(3, errno));
        return (CSTAT(0, 0));
}

static void
wait_twoproc_test(void)
{
        semid_t id;
        int stat;

        if (ksem_open(&id, TEST_PATH, O_CREAT, 0777, 0)) {
                fail_errno("ksem_open");
                return;
        }

        if (schedule_post(id, 500) < 0) {
                ksem_close(id);
                ksem_unlink(TEST_PATH);
                return;
        }               

        if (child_worker(wait_twoproc_child, NULL, &stat) < 0) {
                check_alarm(1);
                ksem_close(id);
                ksem_unlink(TEST_PATH);
                return;
        }

        errno = CSTAT_ERROR(stat);
        switch (CSTAT_CLASS(stat)) {
        case 0:
                pass();
                break;
        case 1:
                fail_errno("child ksem_open()");
                break;
        case 2:
                fail_errno("child ksem_wait()");
                break;
        case 3:
                fail_errno("child ksem_close()");
                break;
        default:
                fail_err("bad child state %#x", stat);
                break;
        }

        check_alarm(1);
        ksem_close(id);
        ksem_unlink(TEST_PATH);
}
TEST(wait_twoproc_test, "two proc wait");

static void
maxvalue_test(void)
{
        semid_t id;
        int val;

        if (ksem_init(&id, SEM_VALUE_MAX) < 0) {
                fail_errno("ksem_init");
                return;
        }
        if (ksem_getvalue(id, &val) < 0) {
                fail_errno("ksem_getvalue");
                ksem_destroy(id);
                return;
        }
        if (val != SEM_VALUE_MAX) {
                fail_err("value %d != SEM_VALUE_MAX");
                ksem_destroy(id);
                return;
        }
        if (val < 0) {
                fail_err("value < 0");
                ksem_destroy(id);
                return;
        }
        if (ksem_destroy(id) < 0) {
                fail_errno("ksem_destroy");
                return;
        }
        pass();
}
TEST(maxvalue_test, "get value of SEM_VALUE_MAX semaphore");

static void
maxvalue_post_test(void)
{
        semid_t id;

        if (ksem_init(&id, SEM_VALUE_MAX) < 0) {
                fail_errno("ksem_init");
                return;
        }

        ksem_post_should_fail(id, EOVERFLOW);

        ksem_destroy(id);
}
TEST(maxvalue_post_test, "post SEM_VALUE_MAX semaphore");

static void
busy_destroy_test(void)
{
        char errbuf[_POSIX2_LINE_MAX];
        struct kinfo_proc *kp;
        semid_t id;
        pid_t pid;
        kvm_t *kd;
        int count;

        kd = kvm_openfiles(NULL, "/dev/null", NULL, O_RDONLY, errbuf);
        if (kd == NULL) {
                fail_err("kvm_openfiles: %s", errbuf);
                return;
        }

        if (ksem_init(&id, 0) < 0) {
                fail_errno("ksem_init");
                kvm_close(kd);
                return;
        }

        pid = fork();
        switch (pid) {
        case -1:
                /* Error. */
                fail_errno("fork");
                ksem_destroy(id);
                kvm_close(kd);
                return;
        case 0:
                /* Child. */
                ksem_wait(id);
                exit(0);
        }

        /*
         * Wait for the child process to block on the semaphore.  This
         * is a bit gross.
         */
        for (;;) {
                kp = kvm_getprocs(kd, KERN_PROC_PID, pid, &count);
                if (kp == NULL) {
                        fail_err("kvm_getprocs: %s", kvm_geterr(kd));
                        kvm_close(kd);
                        ksem_destroy(id);
                        return;
                }
                if (kp->ki_stat == SSLEEP &&
                    (strcmp(kp->ki_wmesg, "sem") == 0 ||
                    strcmp(kp->ki_wmesg, "ksem") == 0))
                        break;
                usleep(1000);
        }
        kvm_close(kd);

        ksem_destroy_should_fail(id, EBUSY);

        /* Cleanup. */
        ksem_post(id);
        waitpid(pid, NULL, 0);
        ksem_destroy(id);
}
TEST(busy_destroy_test, "destroy unnamed semaphore with waiter");

static int
exhaust_unnamed_child(void *arg)
{
        semid_t id;
        int i, max;

        max = (intptr_t)arg;
        for (i = 0; i < max + 1; i++) {
                if (ksem_init(&id, 1) < 0) {
                        if (errno == ENOSPC)
                                return (CSTAT(0, 0));
                        return (CSTAT(1, errno));
                }
        }
        return (CSTAT(2, 0));
}

static void
exhaust_unnamed_sems(void)
{
        size_t len;
        int nsems_max, stat;

        len = sizeof(nsems_max);
        if (sysctlbyname("p1003_1b.sem_nsems_max", &nsems_max, &len, NULL, 0) <
            0) {
                fail_errno("sysctl(p1003_1b.sem_nsems_max)");
                return;
        }

        if (child_worker(exhaust_unnamed_child, (void *)(uintptr_t)nsems_max,
            &stat))
                return;
        errno = CSTAT_ERROR(stat);
        switch (CSTAT_CLASS(stat)) {
        case 0:
                pass();
                break;
        case 1:
                fail_errno("ksem_init");
                break;
        case 2:
                fail_err("Limit of %d semaphores not enforced", nsems_max);
                break;
        default:
                fail_err("bad child state %#x", stat);
                break;
        }
}
TEST(exhaust_unnamed_sems, "exhaust unnamed semaphores (1)");

static int
exhaust_named_child(void *arg)
{
        char buffer[64];
        semid_t id;
        int i, max;

        max = (intptr_t)arg;
        for (i = 0; i < max + 1; i++) {
                snprintf(buffer, sizeof(buffer), "%s%d", TEST_PATH, i);
                if (ksem_open(&id, buffer, O_CREAT, 0777, 1) < 0) {
                        if (errno == ENOSPC || errno == EMFILE ||
                            errno == ENFILE)
                                return (CSTAT(0, 0));
                        return (CSTAT(1, errno));
                }
        }
        return (CSTAT(2, errno));
}

static void
exhaust_named_sems(void)
{
        char buffer[64];
        size_t len;
        int i, nsems_max, stat;

        len = sizeof(nsems_max);
        if (sysctlbyname("p1003_1b.sem_nsems_max", &nsems_max, &len, NULL, 0) <
            0) {
                fail_errno("sysctl(p1003_1b.sem_nsems_max)");
                return;
        }

        if (child_worker(exhaust_named_child, (void *)(uintptr_t)nsems_max,
            &stat) < 0)
                return;
        errno = CSTAT_ERROR(stat);
        switch (CSTAT_CLASS(stat)) {
        case 0:
                pass();
                break;
        case 1:
                fail_errno("ksem_open");
                break;
        case 2:
                fail_err("Limit of %d semaphores not enforced", nsems_max);
                break;
        default:
                fail_err("bad child state %#x", stat);
                break;
        }

        /* Cleanup any semaphores created by the child. */
        for (i = 0; i < nsems_max + 1; i++) {
                snprintf(buffer, sizeof(buffer), "%s%d", TEST_PATH, i);
                ksem_unlink(buffer);
        }
}
TEST(exhaust_named_sems, "exhaust named semaphores (1)");

static int
fdlimit_set(void *arg)
{
        struct rlimit rlim;
        int max;

        max = (intptr_t)arg;
        if (getrlimit(RLIMIT_NOFILE, &rlim) < 0)
                return (CSTAT(3, errno));
        rlim.rlim_cur = max;
        if (setrlimit(RLIMIT_NOFILE, &rlim) < 0)
                return (CSTAT(4, errno));
        return (0);
}

static int
fdlimit_unnamed_child(void *arg)
{
        int stat;

        stat = fdlimit_set(arg);
        if (stat == 0)
                stat = exhaust_unnamed_child(arg);
        return (stat);
}

static void
fdlimit_unnamed_sems(void)
{
        int nsems_max, stat;

        nsems_max = 10;
        if (child_worker(fdlimit_unnamed_child, (void *)(uintptr_t)nsems_max,
            &stat))
                return;
        errno = CSTAT_ERROR(stat);
        switch (CSTAT_CLASS(stat)) {
        case 0:
                pass();
                break;
        case 1:
                fail_errno("ksem_init");
                break;
        case 2:
                fail_err("Limit of %d semaphores not enforced", nsems_max);
                break;
        case 3:
                fail_errno("getrlimit");
                break;
        case 4:
                fail_errno("getrlimit");
                break;
        default:
                fail_err("bad child state %#x", stat);
                break;
        }
}
TEST(fdlimit_unnamed_sems, "exhaust unnamed semaphores (2)");

static int
fdlimit_named_child(void *arg)
{
        int stat;

        stat = fdlimit_set(arg);
        if (stat == 0)
                stat = exhaust_named_child(arg);
        return (stat);
}

static void
fdlimit_named_sems(void)
{
        char buffer[64];
        int i, nsems_max, stat;

        nsems_max = 10;
        if (child_worker(fdlimit_named_child, (void *)(uintptr_t)nsems_max,
            &stat) < 0)
                return;
        errno = CSTAT_ERROR(stat);
        switch (CSTAT_CLASS(stat)) {
        case 0:
                pass();
                break;
        case 1:
                fail_errno("ksem_open");
                break;
        case 2:
                fail_err("Limit of %d semaphores not enforced", nsems_max);
                break;
        case 3:
                fail_errno("getrlimit");
                break;
        case 4:
                fail_errno("getrlimit");
                break;
        default:
                fail_err("bad child state %#x", stat);
                break;
        }

        /* Cleanup any semaphores created by the child. */
        for (i = 0; i < nsems_max + 1; i++) {
                snprintf(buffer, sizeof(buffer), "%s%d", TEST_PATH, i);
                ksem_unlink(buffer);
        }
}
TEST(fdlimit_named_sems, "exhaust named semaphores (2)");

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

        signal(SIGSYS, SIG_IGN);
        run_tests();
        return (0);
}