incubator-nuttx/include/time.h

258 lines
8.3 KiB
C

/****************************************************************************
* include/time.h
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you 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
*
* Unless required by applicable law or agreed to in writing, 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.
*
****************************************************************************/
#ifndef __INCLUDE_TIME_H
#define __INCLUDE_TIME_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/compiler.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.
*/
#define CLOCK_MONOTONIC 1
/* Clock that measures CPU time consumed by this process (i.e., CPU
* time consumed by all threads in the process).
*/
#define CLOCK_PROCESS_CPUTIME_ID 2
/* Clock that measures CPU time consumed by this thread */
#define CLOCK_THREAD_CPUTIME_ID 3
/* Monotonic system-wide clock that includes time spent in suspension. */
#define CLOCK_BOOTTIME 4
/* This is a flag that may be passed to the timer_settime() and
* clock_nanosleep() functions.
*/
#define TIMER_ABSTIME 1
/* Time base values for timespec_get. */
#define TIME_UTC 1
/* Redirect the timelocal and strftime_l */
#define timelocal mktime
#define strftime_l(s, m, f, t, l) strftime(s, m, f, t)
/****************************************************************************
* Public Types
****************************************************************************/
/* Scalar types */
#ifdef CONFIG_SYSTEM_TIME64
typedef uint64_t time_t; /* Holds time in seconds */
#else
typedef uint32_t time_t; /* Holds time in seconds */
#endif
typedef int clockid_t; /* Identifies one time base source */
typedef FAR void *timer_t; /* Represents one POSIX timer */
/* struct timespec is the standard representation of time as seconds and
* nanoseconds.
*/
struct timespec
{
time_t tv_sec; /* Seconds */
long tv_nsec; /* Nanoseconds */
};
/* struct tm is the standard representation for "broken out" time.
*
* REVISIT: This structure could be packed better using uint8_t's and
* uint16_t's. The standard definition does, however, call out type int for
* all of the members. NOTE: Any changes to this structure must be also be
* reflected in struct rtc_time defined in include/nuttx/timers/rtc.h; these
* two structures must be cast compatible.
*/
struct tm
{
int tm_sec; /* Seconds (0-61, allows for leap seconds) */
int tm_min; /* Minutes (0-59) */
int tm_hour; /* Hours (0-23) */
int tm_mday; /* Day of the month (1-31) */
int tm_mon; /* Month (0-11) */
int tm_year; /* Years since 1900 */
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 */
long tm_gmtoff; /* Offset from UTC in seconds */
const char *tm_zone; /* Timezone abbreviation. */
};
/* Struct itimerspec is used to define settings for an interval timer */
struct itimerspec
{
struct timespec it_interval; /* Thereafter */
struct timespec it_value; /* First time */
};
/* forward reference (defined in signal.h) */
struct sigevent;
/****************************************************************************
* Public Data
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
#ifdef CONFIG_LIBC_LOCALTIME
/* daylight - Daylight savings time flag */
/* EXTERN int daylight; not supported */
/* timezone - Difference from UTC and local standard time */
/* EXTERN long int timezone; not supported */
/* tzname[] - Timezone strings
* Setup by tzset()
*/
EXTERN FAR char *tzname[2];
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
clock_t clock(void);
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);
int clock_getcpuclockid(pid_t pid, FAR clockid_t *clockid);
int timespec_get(FAR struct timespec *t, int b);
time_t timegm(FAR struct tm *tp);
time_t mktime(FAR struct tm *tp);
FAR struct tm *gmtime(FAR const time_t *timep);
FAR struct tm *gmtime_r(FAR const time_t *timep, FAR struct tm *result);
FAR struct tm *localtime(FAR const time_t *timep);
FAR struct tm *localtime_r(FAR const time_t *timep, FAR struct tm *result);
size_t strftime(FAR char *s, size_t max, FAR const char *format,
FAR const struct tm *tm) strftime_like(3);
FAR char *strptime(FAR const char *s, FAR const char *format,
FAR struct tm *tm);
FAR char *asctime(FAR const struct tm *tp);
FAR char *asctime_r(FAR const struct tm *tp, FAR char *buf);
FAR char *ctime(FAR const time_t *timep);
FAR char *ctime_r(FAR const time_t *timep, FAR char *buf);
time_t time(FAR time_t *timep);
#ifdef CONFIG_HAVE_DOUBLE
double difftime(time_t time1, time_t time0);
#else
float difftime(time_t time1, time_t time0);
#endif
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 clock_nanosleep(clockid_t clockid, int flags,
FAR const struct timespec *rqtp,
FAR struct timespec *rmtp);
int nanosleep(FAR const struct timespec *rqtp, FAR struct timespec *rmtp);
#ifdef CONFIG_LIBC_LOCALTIME
void tzset(void);
#endif
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_TIME_H */