ClockLatency ALCbackend_getClockLatency(ALCbackend *self)
{
ALCdevice *device = self->mDevice;
ClockLatency ret;
almtx_lock(&self->mMutex);
ret.ClockTime = GetDeviceClockTime(device);
// TODO: Perhaps should be NumUpdates-1 worth of UpdateSize?
ret.Latency = 0;
almtx_unlock(&self->mMutex);
return ret;
}
ClockLatency BackendBase::getClockLatency()
{
ClockLatency ret;
ALuint refcount;
do {
while(((refcount=mDevice->MixCount.load(std::memory_order_acquire))&1))
std::this_thread::yield();
ret.ClockTime = GetDeviceClockTime(mDevice);
std::atomic_thread_fence(std::memory_order_acquire);
} while(refcount != mDevice->MixCount.load(std::memory_order_relaxed));
/* NOTE: The device will generally have about all but one periods filled at
* any given time during playback. Without a more accurate measurement from
* the output, this is an okay approximation.
*/
ret.Latency = std::chrono::seconds{maxi(mDevice->BufferSize-mDevice->UpdateSize, 0)};
ret.Latency /= mDevice->Frequency;
return ret;
}
