camera-streamer/hw/buffer_lock.c
2022-04-05 08:33:27 +02:00

81 lines
1.9 KiB
C

#include "hw/buffer_lock.h"
bool buffer_lock_is_used(buffer_lock_t *buf_lock)
{
int refs = 0;
pthread_mutex_lock(&buf_lock->lock);
refs = buf_lock->refs;
pthread_mutex_unlock(&buf_lock->lock);
return refs;
}
void buffer_lock_use(buffer_lock_t *buf_lock, int ref)
{
pthread_mutex_lock(&buf_lock->lock);
buf_lock->refs += ref;
pthread_mutex_unlock(&buf_lock->lock);
}
bool buffer_lock_needs_buffer(buffer_lock_t *buf_lock)
{
struct timeval now;
gettimeofday(&now, NULL);
bool needs_buffer = false;
pthread_mutex_lock(&buf_lock->lock);
if (now.tv_sec - buf_lock->buf_time.tv_sec > 1) {
buffer_consumed(buf_lock->buf);
buf_lock->buf = NULL;
needs_buffer = true;
}
if (buf_lock->refs > 0) {
needs_buffer = true;
}
pthread_mutex_unlock(&buf_lock->lock);
return needs_buffer;
}
void buffer_lock_capture(buffer_lock_t *buf_lock, buffer_t *buf)
{
pthread_mutex_lock(&buf_lock->lock);
buffer_consumed(buf_lock->buf);
buffer_use(buf);
buf_lock->buf = buf;
buf_lock->counter++;
gettimeofday(&buf_lock->buf_time, NULL);
E_LOG_DEBUG(buf_lock, "Captured HTTP snapshot: %d", buf_lock->counter);
pthread_cond_broadcast(&buf_lock->cond_wait);
pthread_mutex_unlock(&buf_lock->lock);
}
buffer_t *buffer_lock_get(buffer_lock_t *buf_lock, int timeout_s, int *counter)
{
buffer_t *buf = NULL;
struct timeval now;
struct timespec timeout;
gettimeofday(&now, NULL);
timeout.tv_nsec = now.tv_usec;
timeout.tv_sec = now.tv_sec + timeout_s;
pthread_mutex_lock(&buf_lock->lock);
if (*counter == buf_lock->counter || !buf_lock->buf) {
int ret = pthread_cond_timedwait(&buf_lock->cond_wait, &buf_lock->lock, &timeout);
if (ret == ETIMEDOUT) {
goto ret;
} else if (ret < 0) {
goto ret;
}
}
buf = buf_lock->buf;
buffer_use(buf);
*counter = buf_lock->counter;
ret:
pthread_mutex_unlock(&buf_lock->lock);
return buf;
}