Simplify game loop

Only check if events should break the game loop instead of having a
separate member for game loop checking.

src/packages/game/IZ_app.c

@@ -27,7 +27,6 @@ IZ_ProcedureResult IZ_AppInitialize(IZ_App* app) {
 
   // TODO put into its timer module
 	app->ticks = 0;
-	app->quit = false;
 	return 0;
 }
 
@@ -38,15 +37,15 @@ void IZ_AppTeardown(IZ_App* app) {
 	SDL_Quit();
 }
 
-void IZ_AppHandleSDLEvents(IZ_App* app) {
+IZ_ProcedureResult IZ_AppHandleSDLEvents(IZ_App* app) {
 	while (SDL_PollEvent(&app->input_state.sdl_event) != 0) {
 		if (app->input_state.sdl_event.type == SDL_QUIT) {
-			app->quit = true;
-			break;
+			return 1;
 		}
 
 		IZ_InputHandleSDLEvents(&app->input_state);
 	}
+	return 0;
 }
 
 void IZ_AppHandlePortMIDIEvents(IZ_App* app) {
@@ -74,9 +73,12 @@ void IZ_AppHandlePortMIDIEvents(IZ_App* app) {
 	}
 }
 
-void IZ_AppHandleEvents(IZ_App* app) {
-	IZ_AppHandleSDLEvents(app);
+IZ_ProcedureResult IZ_AppHandleEvents(IZ_App* app) {
+	if (IZ_AppHandleSDLEvents(app)) {
+		return 1;
+	}
 	IZ_AppHandlePortMIDIEvents(app);
+	return 0;
 }
 
 IZ_ProcedureResult IZ_AppRun(IZ_App* app, u8 arg_count, char* arg_values[]) {
@@ -98,8 +100,7 @@ IZ_ProcedureResult IZ_AppRun(IZ_App* app, u8 arg_count, char* arg_values[]) {
 		// TODO do audio processing
 		// TODO do networking?
 
-		IZ_AppHandleEvents(app);
-		if (app->quit) {
+		if (IZ_AppHandleEvents(app)) {
 			break;
 		}
 

src/packages/game/IZ_app.h

@@ -2,7 +2,6 @@
 #define IZ_APP_H
 
 #include <SDL.h>
-#include <stdbool.h>
 #ifdef __WIN32__
 #include <getopt.h>
 #else
@@ -18,7 +17,6 @@ typedef struct {
 
 	IZ_Pool pool;
 	u64 ticks;
-	bool quit;
 } IZ_App;
 
 IZ_ProcedureResult IZ_AppRun(IZ_App*, u8, char**);