time.h

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 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
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 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/
/********************************************************************************
 * include/time.h
 *
 *   Copyright (C) 2007-2011, 2013-2014 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.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 NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
 * COPYRIGHT OWNER 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 __INCLUDE_TIME_H
#define __INCLUDE_TIME_H

/********************************************************************************
 * Included Files
 ********************************************************************************/

#include <tinyara/config.h>

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

/********************************************************************************
 * Pre-processor Definitions
 ********************************************************************************/

/* Clock tick of the system (frequency Hz).
 *
 * NOTE: This symbolic name CLK_TCK has been removed from the standard.  It is
 * replaced with CLOCKS_PER_SEC.  Both are defined here.
 *
 * The default value is 100Hz, but this default setting can be overridden by
 * defining the clock interval in microseconds as CONFIG_USEC_PER_TICK in the
 * board configuration file.
 */
#ifdef CONFIG_USEC_PER_TICK
#define CLK_TCK           (1000000/CONFIG_USEC_PER_TICK)
#define CLOCKS_PER_SEC    (1000000/CONFIG_USEC_PER_TICK)
#else
#define CLK_TCK           (100)
#define CLOCKS_PER_SEC    (100)
#endif

/* CLOCK_REALTIME refers to the standard time source.  For most
 * implementations, the standard time source is the system timer interrupt.
 * However, if the platform supports an RTC, then the standard time source
 * will be the RTC for the clock_gettime() and clock_settime() interfaces
 * (the system timer is still the time source for all of the interfaces).
 *
 * CLOCK_REALTIME represents the machine's best-guess as to the current
 * wall-clock, time-of-day time. This means that CLOCK_REALTIME can jump
 * forward and backward as the system time-of-day clock is changed.
 */

#define CLOCK_REALTIME     0

/* Clock that cannot be set and represents monotonic time since some
 * unspecified starting point. It is not affected by changes in the
 * system time-of-day clock.
 */

#ifdef CONFIG_CLOCK_MONOTONIC
#define CLOCK_MONOTONIC  1
#endif

/* This is a flag that may be passed to the timer_settime() function */

#define TIMER_ABSTIME      1

#ifndef CONFIG_LIBC_LOCALTIME
/* Local time is the same as gmtime in this implementation */

#define localtime(c)       gmtime(c)

#define localtime_r(c, r)  gmtime_r(c, r)
#endif

/********************************************************************************
 * Public Types
 ********************************************************************************/

typedef uint32_t time_t;        /* Holds time in seconds */
typedef uint8_t clockid_t;      /* Identifies one time base source */
typedef FAR void *timer_t;      /* Represents one POSIX timer */

struct timespec {
    time_t tv_sec;              /* Seconds */
    long tv_nsec;               /* Nanoseconds */
};

struct timeval {
    time_t tv_sec;              /* Seconds */
    long tv_usec;               /* Microseconds */
};

struct tm {
    int tm_sec;                 /* second (0-61, allows for leap seconds) */
    int tm_min;                 /* minute (0-59) */
    int tm_hour;                /* hour (0-23) */
    int tm_mday;                /* day of the month (1-31) */
    int tm_mon;                 /* month (0-11) */
    int tm_year;                /* years since 1900 */
#ifdef CONFIG_LIBC_LOCALTIME
    int tm_wday;                /* day of the week (0-6) */
    int tm_yday;                /* day of the year (0-365) */
    int tm_isdst;               /* non-0 if daylight savings time is in effect */
#endif
};

struct itimerspec {
    struct timespec it_value;   /* First time */
    struct timespec it_interval;    /* and thereafter */
};

/* forward reference (defined in signal.h) */

struct sigevent;

/********************************************************************************
 * Public Data
 ********************************************************************************/

/* extern char *tznames[]; not supported */

/********************************************************************************
 * Public Function Prototypes
 ********************************************************************************/

#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif

int clock_settime(clockid_t clockid, FAR const struct timespec *tp);
int clock_gettime(clockid_t clockid, FAR struct timespec *tp);
int clock_getres(clockid_t clockid, FAR struct timespec *res);

time_t mktime(FAR struct tm *tp);
FAR struct tm *gmtime(FAR const time_t *timer);
FAR struct tm *gmtime_r(FAR const time_t *timer, FAR struct tm *result);

#ifdef CONFIG_LIBC_LOCALTIME

FAR struct tm *localtime(FAR const time_t *timer);
FAR struct tm *localtime_r(FAR const time_t *timer, FAR struct tm *result);

#endif

size_t strftime(char *s, size_t max, FAR const char *format, FAR const struct tm *tm);

#ifdef CONFIG_ENABLE_IOTIVITY

char *strptime(const char *buf, const char *fmt, struct tm *tm);
#ifdef CONFIG_HAVE_DOUBLE
double difftime(time_t time1, time_t time0);
#else
float difftime(time_t time1, time_t time0);
#endif

#endif

time_t time(FAR time_t *tloc);

int timer_create(clockid_t clockid, FAR struct sigevent *evp, FAR timer_t *timerid);
int timer_delete(timer_t timerid);
int timer_settime(timer_t timerid, int flags, FAR const struct itimerspec *value, FAR struct itimerspec *ovalue);
int timer_gettime(timer_t timerid, FAR struct itimerspec *value);
int timer_getoverrun(timer_t timerid);
int nanosleep(FAR const struct timespec *rqtp, FAR struct timespec *rmtp);

#undef EXTERN
#if defined(__cplusplus)
}
#endif

#endif                          /* __INCLUDE_TIME_H */