Added terminate() to the MusicEngine and publicized

the iMuse implementation. This allows the termination
sequence to be done BEFORE object destruction, so
that the destructor is not making calls that may not
be appropriate during object destruction. (Virtual
functions were the concern, although I'm not sure any
of that was happening anyway. Oh well, better to be
safe than sorry.)

I implemented an empty terminate() in the base class,
but the other MusicEngine derivatives may have stuff
in their destructors that should be moved to this
method. I didn't check.

svn-id: r10452

scumm/imuse.cpp

@@ -69,10 +69,6 @@ _snm_trigger_index(0)
 	memset(_active_notes,0,sizeof(_active_notes));
 }
 
-IMuseInternal::~IMuseInternal() {
-	terminate();
-}
-
 byte *IMuseInternal::findStartOfSound(int sound) {
 	byte *ptr = NULL;
 	int32 size, pos;
@@ -1783,6 +1779,7 @@ int32 IMuse::doCommand (int numargs, int args[]) { in(); int32 ret = _target->do
 int IMuse::clear_queue() { in(); int ret = _target->clear_queue(); out(); return ret; }
 void IMuse::setBase(byte **base) { in(); _target->setBase(base); out(); }
 uint32 IMuse::property(int prop, uint32 value) { in(); uint32 ret = _target->property(prop, value); out(); return ret; }
+void IMuse::terminate() { in(); _target->terminate(); out(); }
 
 // The IMuse::create method provides a front-end factory
 // for creating IMuseInternal without exposing that class

scumm/imuse.h

@@ -74,6 +74,7 @@ public:
 	int clear_queue();
 	void setBase(byte **base);
 	uint32 property(int prop, uint32 value);
+	void terminate();
 
 	// Factory methods
 	static IMuse *create(OSystem *syst, SoundMixer *mixer, MidiDriver *midi);

scumm/imuse_internal.h

@@ -440,7 +440,6 @@ protected:
 
 public:
 	IMuseInternal();
-	~IMuseInternal();
 
 	int initialize(OSystem *syst, SoundMixer *mixer, MidiDriver *midi);
 	void reallocateMidiChannels(MidiDriver *midi);

scumm/music.h

@@ -37,6 +37,7 @@ public:
 	virtual void stopAllSounds() = 0;
 	virtual int  getSoundStatus(int sound) const = 0;
 //	virtual int  getMusicTimer() const = 0;
+	virtual void terminate() {}
 };
 
 #endif

scumm/scummvm.cpp

@@ -824,7 +824,10 @@ Scumm::~Scumm () {
 	delete _confirmExitDialog;
 
 	delete _sound;
+	if (_musicEngine) {
+		_musicEngine->terminate();
 		delete _musicEngine;
+	}
 	free(_languageBuffer);
 	free(_audioNames);