KYRA: Simplify AdLib output code a bit.

This might cause nasty regressions, since it changes the way sounds are
started. On the other hand it gets rid of the low level driver interface
which was implemented before. And it should be a bit better secured against
race conditions.

1 files changed, 130 insertions, 285 deletions

diff --git a/engines/kyra/sound_adlib.cpp b/engines/kyra/sound_adlib.cpp
index 5bbfd024a5..c03975ad9b 100644
--- a/engines/kyra/sound_adlib.cpp
+++ b/engines/kyra/sound_adlib.cpp
@@ -60,7 +60,13 @@ public:
 	AdLibDriver(Audio::Mixer *mixer, bool v2);
 	~AdLibDriver();
 
-	int callback(int opcode, ...);
+	void initDriver();
+	void setSoundData(uint8 *data);
+	void queueTrack(int track);
+	bool isChannelPlaying(int channel) const;
+	void stopAllChannels();
+	int getSoundTrigger() const { return _soundTrigger; }
+
 	void callback();
 
 	// AudioStream API
@@ -97,35 +103,6 @@ public:
 	void setSfxVolume(uint8 volume);
 
 private:
-	struct OpcodeEntry {
-		typedef int (AdLibDriver::*DriverOpcode)(va_list &list);
-		DriverOpcode function;
-		const char *name;
-	};
-
-	void setupOpcodeList();
-	const OpcodeEntry *_opcodeList;
-	int _opcodesEntries;
-
-	int snd_ret0x100(va_list &list);
-	int snd_ret0x1983(va_list &list);
-	int snd_initDriver(va_list &list);
-	int snd_deinitDriver(va_list &list);
-	int snd_setSoundData(va_list &list);
-	int snd_unkOpcode1(va_list &list);
-	int snd_startSong(va_list &list);
-	int snd_isChannelPlaying(va_list &list);
-	int snd_stopChannel(va_list &list);
-	int snd_readByte(va_list &list);
-	int snd_writeByte(va_list &list);
-	int snd_getSoundTrigger(va_list &list);
-	int snd_unkOpcode4(va_list &list);
-	int snd_dummy(va_list &list);
-	int snd_getNullvar4(va_list &list);
-	int snd_setNullvar3(va_list &list);
-	int snd_setFlag(va_list &list);
-	int snd_clearFlag(va_list &list);
-
 	// These variables have not yet been named, but some of them are partly
 	// known nevertheless:
 	//
@@ -351,11 +328,8 @@ private:
 	int32 _samplesTillCallback;
 	int32 _samplesTillCallbackRemainder;
 
-	int _lastProcessed;
-	int8 _flagTrigger;
 	int _curChannel;
 	uint8 _soundTrigger;
-	int _soundsPlaying;
 
 	uint16 _rnd;
 
@@ -380,12 +354,19 @@ private:
 	uint8 _unkValue19;
 	uint8 _unkValue20;
 
-	int _flags;
 	FM_OPL *_adlib;
 
 	uint8 *_soundData;
 
-	uint8 _soundIdTable[0x10];
+	int _programStartTimeout;
+	uint8 *_programQueue[16];
+	int _programQueueStart, _programQueueEnd;
+
+	void adjustSfxData(uint8 *data);
+	uint8 *_sfxPointer;
+	int _sfxPriority;
+	int _sfxVelocity;
+
 	Channel _channels[10];
 
 	uint8 _vibratoAndAMDepthBits;
@@ -417,14 +398,12 @@ private:
 };
 
 AdLibDriver::AdLibDriver(Audio::Mixer *mixer, bool v2) {
-	setupOpcodeList();
 	setupParserOpcodeTable();
 
 	_v2 = v2;
 
 	_mixer = mixer;
 
-	_flags = 0;
 	_adlib = makeAdLibOPL(getRate());
 	assert(_adlib);
 
@@ -433,12 +412,12 @@ AdLibDriver::AdLibDriver(Audio::Mixer *mixer, bool v2) {
 
 	_vibratoAndAMDepthBits = _curRegOffset = 0;
 
-	_lastProcessed = _flagTrigger = _curChannel = _rhythmSectionBits = 0;
-	_soundsPlaying = 0;
+	_curChannel = _rhythmSectionBits = 0;
 	_rnd = 0x1234;
 
 	_tempo = 0;
 	_soundTrigger = 0;
+	_programStartTimeout = 0;
 
 	_callbackTimer = 0xFF;
 	_unkValue1 = _unkValue2 = _unkValue4 = _unkValue5 = 0;
@@ -459,6 +438,10 @@ AdLibDriver::AdLibDriver(Audio::Mixer *mixer, bool v2) {
 
 	_musicVolume = 0;
 	_sfxVolume = 0;
+
+	_sfxPointer = 0;
+
+	_programQueueStart = _programQueueEnd = 0;
 }
 
 AdLibDriver::~AdLibDriver() {
@@ -521,100 +504,54 @@ void AdLibDriver::setSfxVolume(uint8 volume) {
 	}
 }
 
-int AdLibDriver::callback(int opcode, ...) {
+void AdLibDriver::initDriver() {
 	Common::StackLock lock(_mutex);
-	if (opcode >= _opcodesEntries || opcode < 0) {
-		warning("AdLibDriver: calling unknown opcode '%d'", opcode);
-		return 0;
-	}
-
-	debugC(9, kDebugLevelSound, "Calling opcode '%s' (%d)", _opcodeList[opcode].name, opcode);
-
-	va_list args;
-	va_start(args, opcode);
-	int returnValue = (this->*(_opcodeList[opcode].function))(args);
-	va_end(args);
-	return returnValue;
-}
-
-// Opcodes
-
-int AdLibDriver::snd_ret0x100(va_list &list) {
-	return 0x100;
-}
-
-int AdLibDriver::snd_ret0x1983(va_list &list) {
-	return 0x1983;
-}
-
-int AdLibDriver::snd_initDriver(va_list &list) {
-	_lastProcessed = _soundsPlaying = 0;
 	resetAdLibState();
-	return 0;
 }
 
-int AdLibDriver::snd_deinitDriver(va_list &list) {
-	resetAdLibState();
-	return 0;
-}
+void AdLibDriver::setSoundData(uint8 *data) {
+	Common::StackLock lock(_mutex);
+
+	// Drop all tracks that are still queued. These would point to the old
+	// sound data.
+	_programQueueStart = _programQueueEnd = 0;
+	memset(_programQueue, 0, sizeof(_programQueue));
 
-int AdLibDriver::snd_setSoundData(va_list &list) {
 	if (_soundData) {
 		delete[] _soundData;
 		_soundData = 0;
 	}
-	_soundData = va_arg(list, uint8 *);
-	return 0;
-}
 
-int AdLibDriver::snd_unkOpcode1(va_list &list) {
-	warning("unimplemented snd_unkOpcode1");
-	return 0;
+	_soundData = data;
 }
 
-int AdLibDriver::snd_startSong(va_list &list) {
-	int songId = va_arg(list, int);
-	_flags |= 8;
-	_flagTrigger = 1;
+void AdLibDriver::queueTrack(int track) {
+	Common::StackLock lock(_mutex);
 
-	uint8 *ptr = getProgram(songId);
-	assert(ptr);
-	uint8 chan = *ptr;
+	uint8 *trackData = getProgram(track);
+	if (!trackData)
+		return;
 
-	if ((songId << 1) != 0) {
-		if (chan == 9) {
-			if (_flags & 2)
-				return 0;
-		} else {
-			if (_flags & 1)
-				return 0;
-		}
+	if (_programQueueEnd == _programQueueStart && _programQueue[_programQueueEnd] != 0) {
+		warning("AdLibDriver: Program queue full, dropping track %d", track);
+		return;
 	}
 
-	_soundIdTable[_soundsPlaying++] = songId;
-	_soundsPlaying &= 0x0F;
-
-	return 0;
+	_programQueue[_programQueueEnd++] = trackData;
+	_programQueueEnd &= 15;
 }
 
-int AdLibDriver::snd_isChannelPlaying(va_list &list) {
-	int channel = va_arg(list, int);
+bool AdLibDriver::isChannelPlaying(int channel) const {
+	Common::StackLock lock(_mutex);
+
 	assert(channel >= 0 && channel <= 9);
-	return (_channels[channel].dataptr != 0) ? 1 : 0;
+	return (_channels[channel].dataptr != 0);
 }
 
-int AdLibDriver::snd_stopChannel(va_list &list) {
-	int channel = va_arg(list, int);
-
-	int maxChannel;
-	if (channel < 0) {
-		channel = 0;
-		maxChannel = 9;
-	} else {
-		maxChannel = channel;
-	}
+void AdLibDriver::stopAllChannels() {
+	Common::StackLock lock(_mutex);
 
-	for (; channel <= maxChannel; ++channel) {
+	for (int channel = 0; channel <= 9; ++channel) {
 		_curChannel = channel;
 
 		Channel &chan = _channels[_curChannel];
@@ -624,71 +561,16 @@ int AdLibDriver::snd_stopChannel(va_list &list) {
 		if (channel != 9)
 			noteOff(chan);
 	}
-
-	return 0;
-}
-
-int AdLibDriver::snd_readByte(va_list &list) {
-	int a = va_arg(list, int);
-	int b = va_arg(list, int);
-	uint8 *ptr = getProgram(a) + b;
-	assert(ptr);
-	return *ptr;
-}
-
-int AdLibDriver::snd_writeByte(va_list &list) {
-	int a = va_arg(list, int);
-	int b = va_arg(list, int);
-	uint8 value = va_arg(list, int);
-	uint8 *ptr = getProgram(a) + b;
-	assert(ptr);
-	SWAP(*ptr, value);
-	return value;
-}
-
-int AdLibDriver::snd_getSoundTrigger(va_list &list) {
-	return _soundTrigger;
-}
-
-int AdLibDriver::snd_unkOpcode4(va_list &list) {
-	warning("unimplemented snd_unkOpcode4");
-	return 0;
-}
-
-int AdLibDriver::snd_dummy(va_list &list) {
-	return 0;
-}
-
-int AdLibDriver::snd_getNullvar4(va_list &list) {
-	warning("unimplemented snd_getNullvar4");
-	return 0;
-}
-
-int AdLibDriver::snd_setNullvar3(va_list &list) {
-	warning("unimplemented snd_setNullvar3");
-	return 0;
-}
-
-int AdLibDriver::snd_setFlag(va_list &list) {
-	int oldFlags = _flags;
-	_flags |= va_arg(list, int);
-	return oldFlags;
-}
-
-int AdLibDriver::snd_clearFlag(va_list &list) {
-	int oldFlags = _flags;
-	_flags &= ~(va_arg(list, int));
-	return oldFlags;
 }
 
 // timer callback
 
 void AdLibDriver::callback() {
 	Common::StackLock lock(_mutex);
-	--_flagTrigger;
-	if (_flagTrigger < 0)
-		_flags &= ~8;
-	setupPrograms();
+	if (_programStartTimeout)
+		--_programStartTimeout;
+	else
+		setupPrograms();
 	executePrograms();
 
 	uint8 temp = _callbackTimer;
@@ -702,40 +584,79 @@ void AdLibDriver::callback() {
 }
 
 void AdLibDriver::setupPrograms() {
-	while (_lastProcessed != _soundsPlaying) {
-		uint8 *ptr = getProgram(_soundIdTable[_lastProcessed]);
-		uint8 chan = *ptr++;
-		uint8 priority = *ptr++;
-
-		// Only start this sound if its priority is higher than the one
-		// already playing.
-
-		Channel &channel = _channels[chan];
-
-		if (priority >= channel.priority) {
-			initChannel(channel);
-			channel.priority = priority;
-			channel.dataptr = ptr;
-			channel.tempo = 0xFF;
-			channel.position = 0xFF;
-			channel.duration = 1;
-
-			if (chan <= 5)
-				channel.volumeModifier = _musicVolume;
-			else
-				channel.volumeModifier = _sfxVolume;
-
-			unkOutput2(chan);
-		}
+	// If there is no program queued, we skip this.
+	if (_programQueueStart == _programQueueEnd)
+		return;
+
+	uint8 *ptr = _programQueue[_programQueueStart];
+	// Clear the queue entry
+	_programQueue[_programQueueStart] = 0;
+	_programQueueStart = (_programQueueStart + 1) & 15;
+
+	// Adjust data in case we hit a sound effect.
+	adjustSfxData(ptr);
+
+	const int chan = *ptr++;
+	const int priority = *ptr++;
+
+	// Only start this sound if its priority is higher than the one
+	// already playing.
+
+	Channel &channel = _channels[chan];
+
+	if (priority >= channel.priority) {
+		initChannel(channel);
+		channel.priority = priority;
+		channel.dataptr = ptr;
+		channel.tempo = 0xFF;
+		channel.position = 0xFF;
+		channel.duration = 1;
+
+		if (chan <= 5)
+			channel.volumeModifier = _musicVolume;
+		else
+			channel.volumeModifier = _sfxVolume;
 
-		// What we have set up now is, probably, the controlling
-		// channel for the sound. It is assumed that this program will
-		// set up all the other channels it needs, clearing their locks
-		// along the way.
+		unkOutput2(chan);
+	}
+}
 
-		++_lastProcessed;
-		_lastProcessed &= 0x0F;
+void AdLibDriver::adjustSfxData(uint8 *ptr) {
+	// Check whether we need to reset the data of an old sfx which has been
+	// started.
+	if (_sfxPointer) {
+		_sfxPointer[1] = _sfxPriority;
+		_sfxPointer[3] = _sfxVelocity;
+		_sfxPointer = 0;
 	}
+
+	// Only music tracks are started on channel 9, thus we need to make sure
+	// we do not have a music track here.
+	if (*ptr == 9)
+		return;
+
+	// Store the pointer so we can reset the data when a new program is started.
+	_sfxPointer = ptr;
+
+	// Store the old values.
+	_sfxPriority = ptr[1];
+	_sfxVelocity = ptr[3];
+
+	// In the cases I've seen, the mysterious fourth byte has been
+	// the parameter for the update_setExtraLevel3() callback.
+	//
+	// The extra level is part of the channels "total level", which
+	// is a six-bit value where larger values means softer volume.
+	//
+	// So what seems to be happening here is that sounds which are
+	// started by this function are given a slightly lower priority
+	// and a slightly higher (i.e. softer) extra level 3 than they
+	// would have if they were started from anywhere else. Strange.
+
+	// Adjust the values.
+	int newVal = ((((ptr[3]) + 63) * 0xFF) >> 8) & 0xFF;
+	ptr[3] = -newVal + 63;
+	ptr[1] = ((ptr[1] * 0xFF) >> 8) & 0xFF;
 }
 
 // A few words on opcode parsing and timing:
@@ -1410,8 +1331,7 @@ int AdLibDriver::update_setupProgram(uint8 *&dataptr, Channel &channel, uint8 va
 	Channel &channel2 = _channels[chan];
 
 	if (priority >= channel2.priority) {
-		_flagTrigger = 1;
-		_flags |= 8;
+		_programStartTimeout = 2;
 		initChannel(channel2);
 		channel2.priority = priority;
 		channel2.dataptr = ptr;
@@ -2004,32 +1924,6 @@ int AdLibDriver::updateCallback56(uint8 *&dataptr, Channel &channel, uint8 value
 
 #define COMMAND(x) { &AdLibDriver::x, #x }
 
-void AdLibDriver::setupOpcodeList() {
-	static const OpcodeEntry opcodeList[] = {
-		COMMAND(snd_ret0x100),
-		COMMAND(snd_ret0x1983),
-		COMMAND(snd_initDriver),
-		COMMAND(snd_deinitDriver),
-		COMMAND(snd_setSoundData),
-		COMMAND(snd_unkOpcode1),
-		COMMAND(snd_startSong),
-		COMMAND(snd_isChannelPlaying),
-		COMMAND(snd_stopChannel),
-		COMMAND(snd_readByte),
-		COMMAND(snd_writeByte),
-		COMMAND(snd_getSoundTrigger),
-		COMMAND(snd_unkOpcode4),
-		COMMAND(snd_dummy),
-		COMMAND(snd_getNullvar4),
-		COMMAND(snd_setNullvar3),
-		COMMAND(snd_setFlag),
-		COMMAND(snd_clearFlag)
-	};
-
-	_opcodeList = opcodeList;
-	_opcodesEntries = ARRAYSIZE(opcodeList);
-}
-
 void AdLibDriver::setupParserOpcodeTable() {
 	static const ParserOpcode parserOpcodeTable[] = {
 		// 0
@@ -2359,13 +2253,12 @@ SoundAdLibPC::~SoundAdLibPC() {
 }
 
 bool SoundAdLibPC::init() {
-	_driver->callback(2);
-	_driver->callback(16, int(4));
+	_driver->initDriver();
 	return true;
 }
 
 void SoundAdLibPC::process() {
-	uint8 trigger = _driver->callback(11);
+	int trigger = _driver->getSoundTrigger();
 
 	if (trigger < _numSoundTriggers) {
 		int soundId = _soundTriggers[trigger];
@@ -2386,6 +2279,7 @@ void SoundAdLibPC::updateVolumeSettings() {
 	int newMusicVolume = mute ? 0 : ConfMan.getInt("music_volume");
 	//newMusicVolume = (newMusicVolume * 145) / Audio::Mixer::kMaxMixerVolume + 110;
 	newMusicVolume = CLIP(newMusicVolume, 0, 255);
+
 	int newSfxVolume = mute ? 0 : ConfMan.getInt("sfx_volume");
 	//newSfxVolume = (newSfxVolume * 200) / Audio::Mixer::kMaxMixerVolume + 55;
 	newSfxVolume = CLIP(newSfxVolume, 0, 255);
@@ -2416,7 +2310,7 @@ void SoundAdLibPC::haltTrack() {
 }
 
 bool SoundAdLibPC::isPlaying() const {
-	return _driver->callback(7, int(0)) != 0;
+	return _driver->isChannelPlaying(0);
 }
 
 void SoundAdLibPC::playSoundEffect(uint8 track) {
@@ -2435,56 +2329,7 @@ void SoundAdLibPC::play(uint8 track) {
 	if ((soundId == 0xFFFF && _v2) || (soundId == 0xFF && !_v2) || !_soundDataPtr)
 		return;
 
-	// HACK: Since we might call this when the engines is paused (on game load via GMM)
-	// we must unpause the engine here, so this will work properly
-
-	int pauseCount = 0;
-	while (_vm->isPaused()) {
-		++pauseCount;
-		_vm->pauseEngine(false);
-	}
-
-	while ((_driver->callback(16, 0) & 8)) {
-		// We call the system delay and not the game delay to avoid concurrency issues.
-		_vm->_system->delayMillis(10);
-	}
-
-	while (pauseCount--)
-		_vm->pauseEngine(true);
-
-	if (_sfxPlayingSound != -1) {
-		// Restore the sounds's normal values.
-		_driver->callback(10, _sfxPlayingSound, int(1), int(_sfxPriority));
-		_driver->callback(10, _sfxPlayingSound, int(3), int(_sfxFourthByteOfSong));
-		_sfxPlayingSound = -1;
-	}
-
-	int chan = _driver->callback(9, soundId, int(0));
-
-	if (chan != 9) {
-		_sfxPlayingSound = soundId;
-		_sfxPriority = _driver->callback(9, soundId, int(1));
-		_sfxFourthByteOfSong = _driver->callback(9, soundId, int(3));
-
-		// In the cases I've seen, the mysterious fourth byte has been
-		// the parameter for the update_setExtraLevel3() callback.
-		//
-		// The extra level is part of the channels "total level", which
-		// is a six-bit value where larger values means softer volume.
-		//
-		// So what seems to be happening here is that sounds which are
-		// started by this function are given a slightly lower priority
-		// and a slightly higher (i.e. softer) extra level 3 than they
-		// would have if they were started from anywhere else. Strange.
-
-		int newVal = ((((-_sfxFourthByteOfSong) + 63) * 0xFF) >> 8) & 0xFF;
-		newVal = -newVal + 63;
-		_driver->callback(10, soundId, int(3), newVal);
-		newVal = ((_sfxPriority * 0xFF) >> 8) & 0xFF;
-		_driver->callback(10, soundId, int(1), newVal);
-	}
-
-	_driver->callback(6, soundId);
+	_driver->queueTrack(soundId);
 }
 
 void SoundAdLibPC::beginFadeOut() {
@@ -2518,7 +2363,7 @@ void SoundAdLibPC::internalLoadFile(Common::String file) {
 	playSoundEffect(0);
 	playSoundEffect(0);
 
-	_driver->callback(8, int(-1));
+	_driver->stopAllChannels();
 	_soundDataPtr = 0;
 
 	int soundDataSize = fileSize;
@@ -2543,7 +2388,7 @@ void SoundAdLibPC::internalLoadFile(Common::String file) {
 	fileData = p = 0;
 	fileSize = 0;
 
-	_driver->callback(4, _soundDataPtr);
+	_driver->setSoundData(_soundDataPtr);
 
 	_soundFileLoaded = file;
 }