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/* Cabal - Legacy Game Implementations
*
* Cabal is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include "backends/audiocd/audiocd-stream.h"
#include "common/textconsole.h"
AudioCDStream::AudioCDStream() : _buffer(), _frame(0), _bufferPos(0), _bufferFrame(0), _forceStop(false) {
}
AudioCDStream::~AudioCDStream() {
// Stop the timer; the subclass needs to do this,
// so this is just a last resort.
stopTimer();
// Clear any buffered frames
emptyQueue();
}
int AudioCDStream::readBuffer(int16 *buffer, const int numSamples) {
int samples = 0;
// See if any data is left first
while (_bufferPos < kSamplesPerFrame && samples < numSamples)
buffer[samples++] = _buffer[_bufferPos++];
// Bail out if done
if (endOfData())
return samples;
while (samples < numSamples && !endOfData()) {
if (!readNextFrame())
return samples;
// Copy the samples over
for (_bufferPos = 0; _bufferPos < kSamplesPerFrame && samples < numSamples; )
buffer[samples++] = _buffer[_bufferPos++];
}
return samples;
}
bool AudioCDStream::readNextFrame() {
// Fetch a frame from the queue
int16 *buffer;
{
Common::StackLock lock(_mutex);
// Nothing we can do if it's empty
if (_bufferQueue.empty())
return false;
buffer = _bufferQueue.pop();
}
memcpy(_buffer, buffer, kSamplesPerFrame * 2);
delete[] buffer;
_frame++;
return true;
}
bool AudioCDStream::endOfData() const {
return !shouldForceStop() && getStartFrame() + _frame >= getEndFrame() && _bufferPos == kSamplesPerFrame;
}
bool AudioCDStream::seek(const Audio::Timestamp &where) {
// Stop the timer
stopTimer();
// Clear anything out of the queue
emptyQueue();
// Convert to the frame number
// Really not much else needed
_bufferPos = kSamplesPerFrame;
_frame = where.convertToFramerate(kFramesPerSecond).totalNumberOfFrames();
_bufferFrame = _frame;
// Start the timer again
startTimer();
return true;
}
Audio::Timestamp AudioCDStream::getLength() const {
return Audio::Timestamp(0, getEndFrame() - getStartFrame(), kFramesPerSecond);
}
void AudioCDStream::timerProc(void *refCon) {
static_cast<AudioCDStream *>(refCon)->onTimer();
}
void AudioCDStream::onTimer() {
// The goal here is to do as much work in this timer instead
// of doing it in the readBuffer() call, which is the mixer.
// If we're done, bail.
if (shouldForceStop() || getStartFrame() + _bufferFrame >= getEndFrame())
return;
// Get a quick count of the number of items in the queue
// We don't care that much; we only need a quick estimate
_mutex.lock();
uint32 queueCount = _bufferQueue.size();
_mutex.unlock();
// If we have enough audio buffered, bail out
if (queueCount >= kBufferThreshold)
return;
while (!shouldForceStop() && queueCount < kBufferThreshold && getStartFrame() + _bufferFrame < getEndFrame()) {
int16 *buffer = new int16[kSamplesPerFrame];
// Figure out the MSF of the frame we're looking for
int frame = _bufferFrame + getStartFrame();
// Request to read that frame
if (!readFrame(frame, buffer)) {
warning("Failed to read CD audio");
forceStop();
return;
}
_bufferFrame++;
// Now push the buffer onto the queue
Common::StackLock lock(_mutex);
_bufferQueue.push(buffer);
queueCount = _bufferQueue.size();
}
}
void AudioCDStream::startTimer() {
_forceStop = false;
g_system->getTimerManager()->installTimerProc(timerProc, 10 * 1000, this, "AudioCDStream");
}
void AudioCDStream::stopTimer() {
forceStop();
g_system->getTimerManager()->removeTimerProc(timerProc);
}
void AudioCDStream::emptyQueue() {
while (!_bufferQueue.empty())
delete[] _bufferQueue.pop();
}
bool AudioCDStream::shouldForceStop() const {
Common::StackLock lock(_forceStopMutex);
return _forceStop;
}
void AudioCDStream::forceStop() {
Common::StackLock lock(_forceStopMutex);
_forceStop = true;
}
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