An improper locking bug(e.g., deadlock) on the lock &mutex

[ryancaicse]

Hi, developers, thank you for your checking. It seems the lock mutex is not released correctly when num_bytes>0 in the function ao_plugin_play? Should it be a bug or on purpose?

int ao_plugin_play(ao_device *device, const char *output_samples,
		uint_32 num_bytes)
{
  pthread_mutex_lock(&mutex);
   ...;
    if(num_bytes>0){
      long wait = internal->buffersize*1000/(device->output_channels*device->bytewidth*device->rate);
      pthread_mutex_unlock(&mutex);
      wait = (wait/8)*1000;
      if(wait<1)wait=1;
      if(wait>500000)wait=500000;
      usleep(wait);
      pthread_mutex_lock(&mutex);
    }else{
      pthread_mutex_unlock(&mutex);
      break;
    }
  }
  return 1;
}

sela/external/libao/src/plugins/arts/ao_arts.c

Lines 313 to 324 in ca09cbd

	if(num_bytes>0){
	long wait = internal->buffersize*1000/(device->output_channels*device->bytewidth*device->rate);
	pthread_mutex_unlock(&mutex);
	wait = (wait/8)*1000;
	if(wait<1)wait=1;
	if(wait>500000)wait=500000;
	usleep(wait);
	pthread_mutex_lock(&mutex);
	}else{
	pthread_mutex_unlock(&mutex);
	break;
	}

Best,

[ryancaicse]

Hi, developers, any comments are highly appreciated!
@sahaRatul