LCOM1920-T02G10

/*        $NetBSD: clock.h,v 1.3 2014/11/17 17:11:29 christos Exp $        */

/*-

 * Copyright (c) 1996 The NetBSD Foundation, Inc.

 * All rights reserved.

 *

 * This code is derived from software contributed to The NetBSD Foundation

 * by Gordon W. Ross

 *

 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.

 */

#ifndef _SYS_CLOCK_H_

#define _SYS_CLOCK_H_

/* Some handy constants. */

#define SECS_PER_MINUTE                60

#define SECS_PER_HOUR                3600

#define SECS_PER_DAY                86400

#define DAYS_PER_COMMON_YEAR    365

#define DAYS_PER_LEAP_YEAR      366

#define SECS_PER_COMMON_YEAR        (SECS_PER_DAY * DAYS_PER_COMMON_YEAR)

#define SECS_PER_LEAP_YEAR        (SECS_PER_DAY * DAYS_PER_LEAP_YEAR)

/* Traditional POSIX base year */

#define        POSIX_BASE_YEAR        1970

/* Some handy functions */

static inline int

days_in_month(int m)

{

        switch (m) {

        case 2:

                return 28;

        case 4: case 6: case 9: case 11:

                return 30;

        case 1: case 3: case 5: case 7: case 8: case 10: case 12:

                return 31;

        default:

                return -1;

        }

}

/*

 * This inline avoids some unnecessary modulo operations

 * as compared with the usual macro:

 *   ( ((year % 4) == 0 &&

 *      (year % 100) != 0) ||

 *     ((year % 400) == 0) )

 * It is otherwise equivalent.

 */

static inline int

is_leap_year(uint64_t year)

{

        if ((year & 3) != 0)

                return 0;

        if (__predict_false((year % 100) != 0))

                return 1;

        return __predict_false((year % 400) == 0);

}

static inline int

days_per_year(uint64_t year)

{

        return is_leap_year(year) ? DAYS_PER_LEAP_YEAR : DAYS_PER_COMMON_YEAR;

}

#endif /* _SYS_CLOCK_H_ */