mpv/osdep/timer.c

99 lines
2.7 KiB
C

/*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#include <pthread.h>
#include <time.h>
#include <unistd.h>
#include <sys/time.h>
#include <limits.h>
#include <assert.h>
#include "common/common.h"
#include "common/msg.h"
#include "misc/random.h"
#include "timer.h"
static uint64_t raw_time_offset;
static pthread_once_t timer_init_once = PTHREAD_ONCE_INIT;
static void do_timer_init(void)
{
mp_raw_time_init();
mp_rand_seed(mp_raw_time_ns());
raw_time_offset = mp_raw_time_ns();
// Arbitrary additional offset to avoid confusing relative/absolute times.
// Also,we rule that the timer never returns 0 (so default-initialized
// time values will be always in the past).
raw_time_offset -= MP_START_TIME;
}
void mp_time_init(void)
{
pthread_once(&timer_init_once, do_timer_init);
}
int64_t mp_time_ns(void)
{
uint64_t r = mp_raw_time_ns() - raw_time_offset;
if (r < MP_START_TIME)
r = MP_START_TIME;
return r;
}
double mp_time_sec(void)
{
return mp_time_ns() / 1e9;
}
int64_t mp_time_ns_add(int64_t time_ns, double timeout_sec)
{
assert(time_ns > 0); // mp_time_ns() returns strictly positive values
double t = MPCLAMP(timeout_sec * 1e9, -0x1p63, 0x1p63);
int64_t ti = t == 0x1p63 ? INT64_MAX : (int64_t)t;
if (ti > INT64_MAX - time_ns)
return INT64_MAX;
if (ti <= -time_ns)
return 1;
return time_ns + ti;
}
struct timespec mp_time_ns_to_realtime(int64_t time_ns)
{
struct timespec ts = {0};
if (clock_gettime(CLOCK_REALTIME, &ts) != 0)
return ts;
int64_t time_rel = time_ns - mp_time_ns();
// clamp to 1000 days in the future
time_rel = MPMIN(time_rel, 1000 * 24 * 60 * 60 * INT64_C(1000000000));
ts.tv_sec += time_rel / INT64_C(1000000000);
ts.tv_nsec += time_rel % INT64_C(1000000000);
if (ts.tv_nsec >= INT64_C(1000000000)) {
ts.tv_sec++;
ts.tv_nsec -= INT64_C(1000000000);
}
return ts;
}
struct timespec mp_rel_time_to_timespec(double timeout_sec)
{
return mp_time_ns_to_realtime(mp_time_ns_add(mp_time_ns(), timeout_sec));
}