/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2006 David Xu <davidxu@freebsd.org>
 * All rights reserved.
 *
 * 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 unmodified, 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 ``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 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/types.h>
#include <sys/syscall.h>

#include "namespace.h"
#include <errno.h>
#include <stddef.h>
#include <signal.h>
#include <stdlib.h>
#include <time.h>
#include "sigev_thread.h"
#include "un-namespace.h"

extern int __sys_ktimer_create(clockid_t, struct sigevent *__restrict,
        int *__restrict);
extern int __sys_ktimer_delete(int);
extern int __sys_ktimer_gettime(int, struct itimerspec *);
extern int __sys_ktimer_getoverrun(int);
extern int __sys_ktimer_settime(int, int,
        const struct itimerspec *__restrict, struct itimerspec *__restrict);

struct __timer {
        int oshandle;
        struct sigev_node *node;
};

__weak_reference(__timer_create, timer_create);
__weak_reference(__timer_create, _timer_create);
__weak_reference(__timer_delete, timer_delete);
__weak_reference(__timer_delete, _timer_delete);
__weak_reference(__timer_gettime, timer_gettime);
__weak_reference(__timer_gettime, _timer_gettime);
__weak_reference(__timer_settime, timer_settime);
__weak_reference(__timer_settime, _timer_settime);
__weak_reference(__timer_getoverrun, timer_getoverrun);
__weak_reference(__timer_getoverrun, _timer_getoverrun);

typedef void (*timer_func)(union sigval val, int overrun);

static void
timer_dispatch(struct sigev_node *sn)
{
        timer_func f = sn->sn_func;

        /* I want to avoid expired notification. */
        if (sn->sn_info.si_value.sival_int == sn->sn_gen)
                f(sn->sn_value, sn->sn_info.si_overrun);
}

int
__timer_create(clockid_t clockid, struct sigevent *evp, timer_t *timerid)
{
        struct __timer *timer;
        struct sigevent ev;
        struct sigev_node *sn;
        int ret, err;

        timer = malloc(sizeof(struct __timer));
        if (timer == NULL)
                return (-1);

        if (evp == NULL || evp->sigev_notify != SIGEV_THREAD) {
                ret = __sys_ktimer_create(clockid, evp, &timer->oshandle);
                if (ret == -1) {
                        err = errno;
                        free(timer);
                        errno = err;
                        return (ret);
                }
                timer->node = NULL;
                *timerid = timer;
                return (0);
        }

        if (__sigev_check_init()) {
                free(timer);
                errno = EINVAL;
                return (-1);
        }

        sn = __sigev_alloc(SI_TIMER, evp, NULL, 0);
        if (sn == NULL) {
                free(timer);
                errno = EAGAIN;
                return (-1);
        }

        __sigev_get_sigevent(sn, &ev, sn->sn_gen);
        ret = __sys_ktimer_create(clockid, &ev, &timer->oshandle);
        if (ret != 0) {
                err = errno;
                __sigev_free(sn);
                free(timer);
                errno = err;
                return (-1);
        }
        sn->sn_flags |= SNF_SYNC;
        sn->sn_dispatch = timer_dispatch;
        sn->sn_id = timer->oshandle;
        timer->node = sn;
        __sigev_list_lock();
        __sigev_register(sn);
        __sigev_list_unlock();
        *timerid = timer;
        return (0);
}

int
__timer_delete(timer_t timerid)
{
        int ret, err;

        if (timerid->node != NULL) {
                __sigev_list_lock();
                __sigev_delete_node(timerid->node);
                __sigev_list_unlock();
        }
        ret = __sys_ktimer_delete(timerid->oshandle);
        err = errno;
        free(timerid);
        errno = err;
        return (ret);   
}

int
__timer_gettime(timer_t timerid, struct itimerspec *value)
{

        return __sys_ktimer_gettime(timerid->oshandle, value);
}

int
__timer_getoverrun(timer_t timerid)
{

        return __sys_ktimer_getoverrun(timerid->oshandle);
}

int
__timer_settime(timer_t timerid, int flags,
        const struct itimerspec *__restrict value,
        struct itimerspec *__restrict ovalue)
{

        return __sys_ktimer_settime(timerid->oshandle,
                flags, value, ovalue);
}

#pragma weak timer_oshandle_np
int
timer_oshandle_np(timer_t timerid)
{

        return (timerid->oshandle);
}