/*
* Copyright (C) Igor Sysoev
* Copyright (C) NGINX, Inc.
*/
#include <nxt_main.h>
/* OS-specific real, monotonic, and local times and timezone update. */
/* Real time. */
#if (NXT_HAVE_CLOCK_REALTIME_COARSE)
/*
* Linux clock_gettime() resides on the vDSO page. Linux 2.6.32
* clock_gettime(CLOCK_REALTIME_COARSE) uses only cached values and does
* not read TSC or HPET so it has the kernel jiffy precision (1ms by default)
* and it is several times faster than clock_gettime(CLOCK_REALTIME).
*/
void
nxt_realtime(nxt_realtime_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_REALTIME_COARSE, &ts);
now->sec = (nxt_time_t) ts.tv_sec;
now->nsec = ts.tv_nsec;
}
#elif (NXT_HAVE_CLOCK_REALTIME_FAST)
/*
* FreeBSD 7.0 specific clock_gettime(CLOCK_REALTIME_FAST) may be
* 5-30 times faster than clock_gettime(CLOCK_REALTIME) depending
* on kern.timecounter.hardware. The clock has a precision of 1/HZ
* seconds (HZ is 1000 on modern platforms, thus 1ms precision).
* FreeBSD 9.2 clock_gettime() resides on the vDSO page and reads
* TSC. clock_gettime(CLOCK_REALTIME_FAST) is the same as
* clock_gettime(CLOCK_REALTIME).
*/
void
nxt_realtime(nxt_realtime_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_REALTIME_FAST, &ts);
now->sec = (nxt_time_t) ts.tv_sec;
now->nsec = ts.tv_nsec;
}
#elif (NXT_HAVE_CLOCK_REALTIME && !(NXT_HPUX))
/*
* clock_gettime(CLOCK_REALTIME) is supported by Linux, FreeBSD 3.0,
* Solaris 8, NetBSD 1.3, and AIX. HP-UX supports it too, however,
* it is implemented through a call to gettimeofday(). Linux
* clock_gettime(CLOCK_REALTIME) resides on the vDSO page and reads
* TSC or HPET. FreeBSD 9.2 clock_gettime(CLOCK_REALTIME) resides
* on the vDSO page and reads TSC.
*/
void
nxt_realtime(nxt_realtime_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_REALTIME, &ts);
now->sec = (nxt_time_t) ts.tv_sec;
now->nsec = ts.tv_nsec;
}
#else
/* MacOSX, HP-UX. */
void
nxt_realtime(nxt_realtime_t *now)
{
struct timeval tv;
(void) gettimeofday(&tv, NULL);
now->sec = (nxt_time_t) tv.tv_sec;
now->nsec = tv.tv_usec * 1000;
}
#endif
/* Monotonic time. */
#if (NXT_HAVE_CLOCK_MONOTONIC_COARSE)
/*
* Linux clock_gettime() resides on the vDSO page. Linux 2.6.32
* clock_gettime(CLOCK_MONOTONIC_COARSE) uses only cached values and does
* not read TSC or HPET so it has the kernel jiffy precision (1ms by default)
* and it is several times faster than clock_gettime(CLOCK_MONOTONIC).
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_MONOTONIC_COARSE, &ts);
now->monotonic = (nxt_nsec_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
}
#elif (NXT_HAVE_CLOCK_MONOTONIC_FAST)
/*
* FreeBSD 7.0 specific clock_gettime(CLOCK_MONOTONIC_FAST) may be
* 5-30 times faster than clock_gettime(CLOCK_MONOTONIC) depending
* on kern.timecounter.hardware. The clock has a precision of 1/HZ
* seconds (HZ is 1000 on modern platforms, thus 1ms precision).
* FreeBSD 9.2 clock_gettime() resides on the vDSO page and reads
* TSC. clock_gettime(CLOCK_MONOTONIC_FAST) is the same as
* clock_gettime(CLOCK_MONOTONIC).
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_MONOTONIC_FAST, &ts);
now->monotonic = (nxt_nsec_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
}
#elif (NXT_HAVE_HG_GETHRTIME)
/*
* HP-UX 11.31 provides fast hg_gethrtime() which uses a chunk of memory
* shared between userspace application and the kernel, and was introduced
* by Project Mercury ("HG").
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
now->monotonic = (nxt_nsec_t) hg_gethrtime();
}
#elif (NXT_SOLARIS || NXT_HPUX)
/*
* Solaris gethrtime(), clock_gettime(CLOCK_REALTIME), and gettimeofday()
* use a fast systrap whereas clock_gettime(CLOCK_MONOTONIC) and other
* clock_gettime()s use normal systrap. However, the difference is
* negligible on x86_64.
*
* HP-UX lacks clock_gettime(CLOCK_MONOTONIC) but has lightweight
* system call gethrtime().
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
now->monotonic = (nxt_nsec_t) gethrtime();
}
#elif (NXT_HAVE_CLOCK_MONOTONIC)
/*
* clock_gettime(CLOCK_MONOTONIC) is supported by Linux, FreeBSD 5.0,
* Solaris 8, NetBSD 1.6, and AIX. Linux clock_gettime(CLOCK_MONOTONIC)
* resides on the vDSO page and reads TSC or HPET. FreeBSD 9.2
* clock_gettime(CLOCK_MONOTONIC) resides on the vDSO page and reads TSC.
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
struct timespec ts;
(void) clock_gettime(CLOCK_MONOTONIC, &ts);
now->monotonic = (nxt_nsec_t) ts.tv_sec * 1000000000 + ts.tv_nsec;
}
#elif (NXT_MACOSX)
/*
* MacOSX does not support clock_gettime(), but mach_absolute_time() returns
* monotonic ticks. To get nanoseconds the ticks should be multiplied then
* divided by numerator/denominator returned by mach_timebase_info(), however
* on modern MacOSX they are 1/1. On PowerPC MacOSX these values were
* 1000000000/33333335 or 1000000000/25000000, on iOS 4+ they were 125/3,
* and on iOS 3 they were 1000000000/24000000.
*/
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
now->monotonic = mach_absolute_time();
}
#else
void
nxt_monotonic_time(nxt_monotonic_time_t *now)
{
nxt_nsec_t current;
nxt_nsec_int_t delta;
struct timeval tv;
(void) gettimeofday(&tv, NULL);
now->realtime.sec = (nxt_time_t) tv.tv_sec;
now->realtime.nsec = tv.tv_usec * 1000;
/*
* Monotonic time emulation using gettimeofday()
* for platforms which lack monotonic time.
*/
current = (nxt_nsec_t) tv.tv_sec * 1000000000 + tv.tv_usec * 1000;
delta = current - now->previous;
now->previous = current;
if (delta > 0) {
now->monotonic += delta;
} else {
/* The time went backward. */
now->monotonic++;
}
/*
* Eliminate subsequent gettimeofday() call
* in nxt_thread_realtime_update().
*/
now->update = now->monotonic + 1;
}
#endif
/* Local time. */
#if (NXT_HAVE_LOCALTIME_R)
void
nxt_localtime(nxt_time_t s, struct tm *tm)
{
time_t _s;
_s = (time_t) s;
(void) localtime_r(&_s, tm);
}
#else
void
nxt_localtime(nxt_time_t s, struct tm *tm)
{
time_t _s;
struct tm *_tm;
_s = (time_t) s;
_tm = localtime(&_s);
*tm = *_tm;
}
#endif
/* Timezone update. */
#if (NXT_LINUX)
/*
* Linux glibc does not test /etc/localtime change
* in localtime_r(), but tests in localtime().
*/
void
nxt_timezone_update(void)
{
time_t s;
s = time(NULL);
(void) localtime(&s);
}
#elif (NXT_FREEBSD)
/*
* FreeBSD libc does not test /etc/localtime change, but it can be
* worked around by calling tzset() with TZ and then without TZ
* to update timezone. This trick should work since FreeBSD 2.1.0.
*/
void
nxt_timezone_update(void)
{
if (getenv("TZ") != NULL) {
return;
}
/* The libc uses /etc/localtime if TZ is not set. */
(void) putenv((char *) "TZ=UTC");
tzset();
(void) unsetenv("TZ");
tzset();
}
#elif (NXT_SOLARIS)
/*
* Solaris 10, patch 142909-17 introduced tzreload(8):
*
* The tzreload command notifies active (running) processes to reread
* timezone information. The timezone information is cached in each
* process, absent a tzreload command, is never reread until a process
* is restarted. In response to a tzreload command, active processes
* reread the current timezone information at the next call to ctime(3C)
* and mktime(3C). By default, the tzreload notification is sent to
* the processes within the current zone.
*/
void
nxt_timezone_update(void)
{
time_t s;
s = time(NULL);
(void) ctime(&s);
}
#else
void
nxt_timezone_update(void)
{
return;
}
#endif
