libsaria: Added callback framework

I have created generic functions for registering and triggering
callbacks.  New callbacks can be added by creating a new constant in the
callback_t enum.

include/libsaria/callback.h

@@ -0,0 +1,9 @@
+#ifndef LIBSARIA_CALLBACKS_H
+#define LIBSARIA_CALLBACKS_H
+
+enum callback_t {
+	PLAY,
+	PAUSE,
+};
+
+#endif /* LIBSARIA_CALLBACKS_H */

include/libsaria/libsaria.h

@@ -2,18 +2,21 @@
 #define LIBSARIA_H
 
 #include <libsaria/audio.h>
+#include <libsaria/callback.h>
 #include <libsaria/print.h>
 
 class Libsaria
 {
 	private:
 		Audio audio;
+		void trigger_callback(callback_t);
 
 	public:
 		Libsaria(int, char**);
 		~Libsaria();
 
 		void load(string);
+		void register_callback(callback_t, void (*)());
 
 		/* Control functions */
 		void play();

libsaria/callback.cpp

@@ -0,0 +1,21 @@
+
+#include <libsaria/libsaria.h>
+#include <libsaria/callback.h>
+
+#include <map>
+using namespace std;
+
+static map<callback_t, void (*)()> callbacks;
+
+void Libsaria::trigger_callback(callback_t type)
+{
+	map<callback_t, void (*)()>::iterator it;
+	it=callbacks.find(type);
+	if (it != callbacks.end())
+		it->second();
+}
+
+void Libsaria::register_callback(callback_t type, void (* func)())
+{
+	callbacks[type] = func;
+}

libsaria/controls.cpp

@@ -4,12 +4,14 @@
 
 void Libsaria::play()
 {
-	audio.play();
+	if(audio.play())
+		trigger_callback(PLAY);
 }
 
 void Libsaria::pause()
 {
-	audio.pause();
+	if(audio.pause())
+		trigger_callback(PAUSE);
 }
 
 void Libsaria::stop()

libsaria/libsaria.cpp

@@ -15,5 +15,5 @@ Libsaria::~Libsaria()
 void Libsaria::load(string filepath)
 {
 	audio.load(filepath);
-	audio.play();
+	play();
 }