mpv/osdep/threads.c

82 lines
2.4 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 General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <time.h>
#include <unistd.h>
#include <sys/time.h>
#include <limits.h>
#include "common/common.h"
#include "threads.h"
static void get_pthread_time(struct timespec *out_ts)
{
#if defined(_POSIX_TIMERS) && _POSIX_TIMERS > 0
clock_gettime(CLOCK_REALTIME, out_ts);
#else
// OSX
struct timeval tv;
gettimeofday(&tv, NULL);
out_ts->tv_sec = tv.tv_sec;
out_ts->tv_nsec = tv.tv_usec * 1000UL;
#endif
}
static void timespec_add_seconds(struct timespec *ts, double seconds)
{
// clamp to 1 week to avoid tv_sec overflows
seconds = MPMIN(seconds, 60 * 60 * 24 * 7);
unsigned long secs = (int)seconds;
unsigned long nsecs = (seconds - secs) * 1000000000UL;
if (nsecs + ts->tv_nsec >= 1000000000UL) {
secs += 1;
nsecs -= 1000000000UL;
}
ts->tv_sec += secs;
ts->tv_nsec += nsecs;
}
// Return the argument to pass to e.g. pthread_cond_timedwait().
// (Note that pthread_cond_t supports multiple clocks; this function computes
// the time value needed by the default clock.)
struct timespec mpthread_get_deadline(double timeout)
{
struct timespec ts;
get_pthread_time(&ts);
timespec_add_seconds(&ts, timeout);
return ts;
}
// Call pthread_cond_timedwait() with a relative timeout in seconds
int mpthread_cond_timedwait(pthread_cond_t *cond, pthread_mutex_t *mutex,
double timeout)
{
struct timespec ts = mpthread_get_deadline(timeout);
return pthread_cond_timedwait(cond, mutex, &ts);
}
// Helper to reduce boiler plate.
int mpthread_mutex_init_recursive(pthread_mutex_t *mutex)
{
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
int r = pthread_mutex_init(mutex, &attr);
pthread_mutexattr_destroy(&attr);
return r;
}