/*-
 * Copyright (c) 2014-2015 François Tigeot
 * 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.
 */
#ifndef _LINUXKPI_LINUX_TIME_H_
#define _LINUXKPI_LINUX_TIME_H_

#define MSEC_PER_SEC    1000L

#define NSEC_PER_USEC   1000L
#define NSEC_PER_MSEC   1000000L
#define NSEC_PER_SEC    1000000000L

#define USEC_PER_MSEC   1000L
#define USEC_PER_SEC    1000000L

#define timespec64 timespec

#include <sys/time.h>
#include <sys/stdint.h>

#include <linux/math64.h>

typedef int64_t time64_t;

static inline struct timeval
ns_to_timeval(const int64_t nsec)
{
        struct timeval tv;
        long rem;

        if (nsec == 0) {
                tv.tv_sec = 0;
                tv.tv_usec = 0;
                return (tv);
        }

        tv.tv_sec = nsec / NSEC_PER_SEC;
        rem = nsec % NSEC_PER_SEC;
        if (rem < 0) {
                tv.tv_sec--;
                rem += NSEC_PER_SEC;
        }
        tv.tv_usec = rem / 1000;
        return (tv);
}

static inline int64_t
timeval_to_ns(const struct timeval *tv)
{
        return ((int64_t)tv->tv_sec * NSEC_PER_SEC) +
                tv->tv_usec * NSEC_PER_USEC;
}

#define getrawmonotonic(ts)     nanouptime(ts)

static inline struct timespec
timespec_sub(struct timespec lhs, struct timespec rhs)
{
        struct timespec ts;

        timespecsub(&lhs, &rhs, &ts);

        return ts;
}

static inline void
set_normalized_timespec(struct timespec *ts, time_t sec, int64_t nsec)
{
        /* XXX: this doesn't actually normalize anything */
        ts->tv_sec = sec;
        ts->tv_nsec = nsec;
}

static inline int64_t
timespec_to_ns(const struct timespec *ts)
{
        return ((ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec);
}

static inline struct timespec
ns_to_timespec(const int64_t nsec)
{
        struct timespec ts;
        int32_t rem;

        if (nsec == 0) {
                ts.tv_sec = 0;
                ts.tv_nsec = 0;
                return (ts);
        }

        ts.tv_sec = nsec / NSEC_PER_SEC;
        rem = nsec % NSEC_PER_SEC;
        if (rem < 0) {
                ts.tv_sec--;
                rem += NSEC_PER_SEC;
        }
        ts.tv_nsec = rem;
        return (ts);
}

#define ns_to_timespec64(_x)    ns_to_timespec(_x)

static inline int
timespec_valid(const struct timespec *ts)
{
        if (ts->tv_sec < 0 || ts->tv_sec > 100000000 ||
            ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000)
                return (0);
        return (1);
}

static inline unsigned long
get_seconds(void)
{
        return time_uptime;
}

#endif /* _LINUXKPI_LINUX_TIME_H_ */