yolobs-studio/deps/libff/libff/ff-clock.c
2019-09-22 23:19:10 +02:00

141 lines
3.5 KiB
C

/*
* Copyright (c) 2015 John R. Bradley <jrb@turrettech.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include "ff-clock.h"
#include "ff-threading.h"
#include <libavutil/avutil.h>
#include <libavutil/time.h>
// Amount of microseconds between checks to see if a clock has started
#define CLOCK_START_CHECK_INTERVAL 100
double ff_get_sync_clock(struct ff_clock *clock)
{
return clock->sync_clock(clock->opaque);
}
int64_t ff_clock_start_time(struct ff_clock *clock)
{
int64_t start_time = AV_NOPTS_VALUE;
pthread_mutex_lock(&clock->mutex);
if (clock->started)
start_time = clock->start_time;
pthread_mutex_unlock(&clock->mutex);
return start_time;
}
bool ff_clock_start(struct ff_clock *clock, enum ff_av_sync_type sync_type,
const bool *abort)
{
bool release = false;
bool aborted = false;
if (clock->sync_type == sync_type && !clock->started) {
pthread_mutex_lock(&clock->mutex);
if (!clock->started) {
clock->start_time = av_gettime();
clock->started = true;
}
pthread_cond_signal(&clock->cond);
pthread_mutex_unlock(&clock->mutex);
} else {
while (!clock->started) {
pthread_mutex_lock(&clock->mutex);
int64_t current_time =
av_gettime() + CLOCK_START_CHECK_INTERVAL;
struct timespec sleep_time = {
.tv_sec = current_time / AV_TIME_BASE,
.tv_nsec =
(current_time % AV_TIME_BASE) * 1000};
pthread_cond_timedwait(&clock->cond, &clock->mutex,
&sleep_time);
aborted = *abort;
// There is no way anyone can signal us since we are
// the only reference
if (clock->retain == 1)
release = true;
pthread_mutex_unlock(&clock->mutex);
if (aborted || release) {
av_log(NULL, AV_LOG_ERROR,
"could not start "
"slave clock as master clock "
"was never started before "
"being released or aborted");
break;
}
}
}
if (release)
ff_clock_release(&clock);
return !release && !aborted;
}
struct ff_clock *ff_clock_init(void)
{
struct ff_clock *clock = av_mallocz(sizeof(struct ff_clock));
if (clock == NULL)
return NULL;
if (pthread_mutex_init(&clock->mutex, NULL) != 0)
goto fail;
if (pthread_cond_init(&clock->cond, NULL) != 0)
goto fail1;
return clock;
fail1:
pthread_mutex_destroy(&clock->mutex);
fail:
av_free(clock);
return NULL;
}
struct ff_clock *ff_clock_retain(struct ff_clock *clock)
{
ff_atomic_inc_long(&clock->retain);
return clock;
}
struct ff_clock *ff_clock_move(struct ff_clock **clock)
{
struct ff_clock *retained_clock = ff_clock_retain(*clock);
ff_clock_release(clock);
return retained_clock;
}
void ff_clock_release(struct ff_clock **clock)
{
if (ff_atomic_dec_long(&(*clock)->retain) == 0) {
pthread_cond_destroy(&(*clock)->cond);
pthread_mutex_destroy(&(*clock)->mutex);
av_free(*clock);
}
*clock = NULL;
}