Increased robustness of audio module initialization (see issue #646.) Also changed Source:play to return a boolean indicating success.

src/modules/audio/null/Audio.cpp

@@ -61,12 +61,9 @@ int Audio::getMaxSources() const
 	return 0;
 }
 
-void Audio::play(love::audio::Source *)
-{
-}
-
-void Audio::play()
+bool Audio::play(love::audio::Source *)
 {
+	return false;
 }
 
 void Audio::stop(love::audio::Source *)

src/modules/audio/null/Audio.h

@@ -48,8 +48,7 @@ public:
 	love::audio::Source *newSource(love::sound::SoundData *soundData);
 	int getSourceCount() const;
 	int getMaxSources() const;
-	void play(love::audio::Source *source);
-	void play();
+	bool play(love::audio::Source *source);
 	void stop(love::audio::Source *source);
 	void stop();
 	void pause(love::audio::Source *source);

src/modules/audio/null/Source.cpp

@@ -42,8 +42,9 @@ love::audio::Source *Source::clone()
 	return this;
 }
 
-void Source::play()
+bool Source::play()
 {
+	return false;
 }
 
 void Source::stop()

src/modules/audio/null/Source.h

@@ -39,7 +39,7 @@ public:
 	virtual ~Source();
 
 	virtual love::audio::Source *clone();
-	virtual void play();
+	virtual bool play();
 	virtual void stop();
 	virtual void pause();
 	virtual void resume();