SCI: queuing signal, if signal not passed to scripts

fixes laura bow 1 when knocking at the door in the attic, scripts wait for 0xb in that case, sound resource sets 0xb and then immediately ends. This resulted in the scripts only getting the termination signal, so they waited endlessly. (bug #3042981)

svn-id: r52043

3 files changed, 27 insertions, 2 deletions

diff --git a/engines/sci/sound/midiparser_sci.cpp b/engines/sci/sound/midiparser_sci.cpp
index 6ec28a8b02..769df73365 100644
--- a/engines/sci/sound/midiparser_sci.cpp
+++ b/engines/sci/sound/midiparser_sci.cpp
@@ -445,7 +445,12 @@ void MidiParser_SCI::parseNextEvent(EventInfo &info) {
 	}
 	if (_signalSet) {
 		_signalSet = false;
-		_pSnd->signal = _signalToSet;
+		if (!_pSnd->signal) {
+			_pSnd->signal = _signalToSet;
+		} else {
+			// signal already set and waiting for getting to scripts, queue new one
+			_pSnd->signalQueue.push_back(_signalToSet);
+		}
 		debugC(4, kDebugLevelSound, "signal %04x", _signalToSet);
 	}
 
@@ -608,7 +613,12 @@ void MidiParser_SCI::parseNextEvent(EventInfo &info) {
 					jumpToTick(_loopTick);
 				} else {
 					_pSnd->status = kSoundStopped;
-					_pSnd->signal = SIGNAL_OFFSET;
+					if (!_pSnd->signal) {
+						_pSnd->signal = SIGNAL_OFFSET;
+					} else {
+						// signal already set and waiting for getting to scripts, queue new one
+						_pSnd->signalQueue.push_back(SIGNAL_OFFSET);
+					}
 
 					debugC(4, kDebugLevelSound, "signal EOT");
 				}
diff --git a/engines/sci/sound/music.cpp b/engines/sci/sound/music.cpp
index c9a7de7b1c..fc1e56fcea 100644
--- a/engines/sci/sound/music.cpp
+++ b/engines/sci/sound/music.cpp
@@ -638,6 +638,14 @@ MusicEntry::~MusicEntry() {
 }
 
 void MusicEntry::onTimer() {
+	if (!signal) {
+		if (!signalQueue.empty()) {
+			// no signal set, but signal in queue, set that one
+			signal = signalQueue[0];
+			signalQueue.remove_at(0);
+		}
+	}
+
 	if (status != kSoundPlaying)
 		return;
 
diff --git a/engines/sci/sound/music.h b/engines/sci/sound/music.h
index 37e3c30030..3cf600fcf3 100644
--- a/engines/sci/sound/music.h
+++ b/engines/sci/sound/music.h
@@ -51,6 +51,8 @@ enum SoundStatus {
 class MidiParser_SCI;
 class SegManager;
 
+typedef Common::Array<uint16> SignalQueue;
+
 class MusicEntry : public Common::Serializable {
 public:
 	// Do not get these directly for the sound objects!
@@ -90,6 +92,11 @@ public:
 
 	MidiParser_SCI *pMidiParser;
 
+	// this is used for storing signals, when the current signal is not yet
+	//  sent to the scripts. We shouldn't need to save it, this normally only
+	//  happens in rare situations like lb1, knocking on the door in the attic
+	SignalQueue signalQueue;
+
 	// TODO: We need to revise how we store the different
 	// audio stream objects we require.
 	Audio::RewindableAudioStream *pStreamAud;