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// SPDX-License-Identifier: GPL-3.0-or-later
#ifndef NETDATA_CLOCKS_H
#define NETDATA_CLOCKS_H 1
#include "../libnetdata.h"
#ifndef HAVE_STRUCT_TIMESPEC
struct timespec {
time_t tv_sec; /* seconds */
long tv_nsec; /* nanoseconds */
};
#endif
#ifndef HAVE_CLOCKID_T
typedef int clockid_t;
#endif
typedef unsigned long long nsec_t;
typedef unsigned long long msec_t;
typedef unsigned long long usec_t;
typedef long long susec_t;
typedef struct heartbeat {
usec_t monotonic;
usec_t realtime;
} heartbeat_t;
/* Linux value is as good as any other */
#ifndef CLOCK_REALTIME
#define CLOCK_REALTIME 0
#endif
#ifndef CLOCK_MONOTONIC
/* fallback to CLOCK_REALTIME if not available */
#define CLOCK_MONOTONIC CLOCK_REALTIME
#endif
/* Prefer CLOCK_MONOTONIC_COARSE where available to reduce overhead. It has the same semantics as CLOCK_MONOTONIC */
#ifndef CLOCK_MONOTONIC_COARSE
/* fallback to CLOCK_MONOTONIC if not available */
#define CLOCK_MONOTONIC_COARSE CLOCK_MONOTONIC
#endif
#ifndef CLOCK_BOOTTIME
#ifdef CLOCK_UPTIME
/* CLOCK_BOOTTIME falls back to CLOCK_UPTIME on FreeBSD */
#define CLOCK_BOOTTIME CLOCK_UPTIME
#else // CLOCK_UPTIME
/* CLOCK_BOOTTIME falls back to CLOCK_MONOTONIC */
#define CLOCK_BOOTTIME CLOCK_MONOTONIC_COARSE
#endif // CLOCK_UPTIME
#else // CLOCK_BOOTTIME
#ifdef HAVE_CLOCK_GETTIME
#define CLOCK_BOOTTIME_IS_AVAILABLE 1 // required for /proc/uptime
#endif // HAVE_CLOCK_GETTIME
#endif // CLOCK_BOOTTIME
#ifndef NSEC_PER_MSEC
#define NSEC_PER_MSEC 1000000ULL
#endif
#ifndef NSEC_PER_SEC
#define NSEC_PER_SEC 1000000000ULL
#endif
#ifndef NSEC_PER_USEC
#define NSEC_PER_USEC 1000ULL
#endif
#ifndef USEC_PER_SEC
#define USEC_PER_SEC 1000000ULL
#endif
#ifndef MSEC_PER_SEC
#define MSEC_PER_SEC 1000ULL
#endif
#define USEC_PER_MS 1000ULL
#ifndef HAVE_CLOCK_GETTIME
/* Fallback function for POSIX.1-2001 clock_gettime() function.
*
* We use a realtime clock from gettimeofday(), this will
* make systems without clock_gettime() support sensitive
* to time jumps or hibernation/suspend side effects.
*/
extern int clock_gettime(clockid_t clk_id, struct timespec *ts);
#endif
/*
* Three clocks are available (cf. man 3 clock_gettime):
*
* REALTIME clock (i.e. wall-clock):
* This clock is affected by discontinuous jumps in the system time
* (e.g., if the system administrator manually changes the clock), and by the incremental adjustments performed by adjtime(3) and NTP.
*
* MONOTONIC clock
* Clock that cannot be set and represents monotonic time since some unspecified starting point.
* This clock is not affected by discontinuous jumps in the system time
* (e.g., if the system administrator manually changes the clock), but is affected by the incremental adjustments performed by adjtime(3) and NTP.
* If not available on the system, this clock falls back to REALTIME clock.
*
* BOOTTIME clock
* Identical to CLOCK_MONOTONIC, except it also includes any time that the system is suspended.
* This allows applications to get a suspend-aware monotonic clock without having to deal with the complications of CLOCK_REALTIME,
* which may have discontinuities if the time is changed using settimeofday(2).
* If not available on the system, this clock falls back to MONOTONIC clock.
*
* All now_*_timeval() functions fill the `struct timeval` with the time from the appropriate clock.
* Those functions return 0 on success, -1 else with errno set appropriately.
*
* All now_*_sec() functions return the time in seconds from the approriate clock, or 0 on error.
* All now_*_usec() functions return the time in microseconds from the approriate clock, or 0 on error.
*
* Most functions will attempt to use CLOCK_MONOTONIC_COARSE if available to reduce contention overhead and improve
* performance scaling. If high precision is required please use one of the available now_*_high_precision_* functions.
*/
extern int now_realtime_timeval(struct timeval *tv);
extern time_t now_realtime_sec(void);
extern usec_t now_realtime_usec(void);
extern int now_monotonic_timeval(struct timeval *tv);
extern time_t now_monotonic_sec(void);
extern usec_t now_monotonic_usec(void);
extern int now_monotonic_high_precision_timeval(struct timeval *tv);
extern time_t now_monotonic_high_precision_sec(void);
extern usec_t now_monotonic_high_precision_usec(void);
extern int now_boottime_timeval(struct timeval *tv);
extern time_t now_boottime_sec(void);
extern usec_t now_boottime_usec(void);
extern usec_t timeval_usec(struct timeval *tv);
extern msec_t timeval_msec(struct timeval *tv);
extern usec_t dt_usec(struct timeval *now, struct timeval *old);
extern susec_t dt_usec_signed(struct timeval *now, struct timeval *old);
extern void heartbeat_init(heartbeat_t *hb);
/* Sleeps until next multiple of tick using monotonic clock.
* Returns elapsed time in microseconds since previous heartbeat
*/
extern usec_t heartbeat_next(heartbeat_t *hb, usec_t tick);
/* Returns elapsed time in microseconds since last heartbeat */
extern usec_t heartbeat_monotonic_dt_to_now_usec(heartbeat_t *hb);
extern int sleep_usec(usec_t usec);
/*
* When running a binary with CLOCK_BOOTTIME defined on a system with a linux kernel older than Linux 2.6.39 the
* clock_gettime(2) system call fails with EINVAL. In that case it must fall-back to CLOCK_MONOTONIC.
*/
void test_clock_boottime(void);
/*
* When running a binary with CLOCK_MONOTONIC_COARSE defined on a system with a linux kernel older than Linux 2.6.32 the
* clock_gettime(2) system call fails with EINVAL. In that case it must fall-back to CLOCK_MONOTONIC.
*/
void test_clock_monotonic_coarse(void);
extern collected_number uptime_msec(char *filename);
#endif /* NETDATA_CLOCKS_H */
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