Add thread-interrupt functions for having multiple threads that want to pause the GBA thread

src/gba/gba-thread.c

@@ -37,6 +37,12 @@ static void _changeState(struct GBAThread* threadContext, enum ThreadState newSt
 	MutexUnlock(&threadContext->stateMutex);
 }
 
+static void _waitOnInterrupt(struct GBAThread* threadContext) {
+	while (threadContext->state == THREAD_INTERRUPTED) {
+		ConditionWait(&threadContext->stateCond, &threadContext->stateMutex);
+	}
+}
+
 static THREAD_ENTRY _GBAThreadRun(void* context) {
 #ifdef USE_PTHREADS
 	pthread_once(&_contextOnce, _createTLS);
@@ -122,7 +128,7 @@ static THREAD_ENTRY _GBAThreadRun(void* context) {
 			}
 		}
 		MutexLock(&threadContext->stateMutex);
-		while (threadContext->state == THREAD_PAUSED) {
+		while (threadContext->state == THREAD_PAUSED || threadContext->state == THREAD_INTERRUPTED) {
 			ConditionWait(&threadContext->stateCond, &threadContext->stateMutex);
 		}
 		MutexUnlock(&threadContext->stateMutex);
@@ -239,9 +245,25 @@ void GBAThreadJoin(struct GBAThread* threadContext) {
 	free(threadContext->rewindBuffer);
 }
 
+void GBAThreadInterrupt(struct GBAThread* threadContext) {
+	MutexLock(&threadContext->stateMutex);
+	_waitOnInterrupt(threadContext);
+	threadContext->savedState = threadContext->state;
+	threadContext->state = THREAD_INTERRUPTED;
+	if (threadContext->debugger && threadContext->debugger->state == DEBUGGER_RUNNING) {
+		threadContext->debugger->state = DEBUGGER_EXITING;
+	}
+	MutexUnlock(&threadContext->stateMutex);
+}
+
+void GBAThreadContinue(struct GBAThread* threadContext) {
+	_changeState(threadContext, threadContext->savedState, 1);
+}
+
 void GBAThreadPause(struct GBAThread* threadContext) {
 	int frameOn = 1;
 	MutexLock(&threadContext->stateMutex);
+	_waitOnInterrupt(threadContext);
 	if (threadContext->state == THREAD_RUNNING) {
 		if (threadContext->debugger && threadContext->debugger->state == DEBUGGER_RUNNING) {
 			threadContext->debugger->state = DEBUGGER_EXITING;
@@ -261,6 +283,7 @@ void GBAThreadPause(struct GBAThread* threadContext) {
 void GBAThreadUnpause(struct GBAThread* threadContext) {
 	int frameOn = 1;
 	MutexLock(&threadContext->stateMutex);
+	_waitOnInterrupt(threadContext);
 	if (threadContext->state == THREAD_PAUSED) {
 		threadContext->state = THREAD_RUNNING;
 		ConditionWake(&threadContext->stateCond);
@@ -277,6 +300,7 @@ void GBAThreadUnpause(struct GBAThread* threadContext) {
 int GBAThreadIsPaused(struct GBAThread* threadContext) {
 	int isPaused;
 	MutexLock(&threadContext->stateMutex);
+	_waitOnInterrupt(threadContext);
 	isPaused = threadContext->state == THREAD_PAUSED;
 	MutexUnlock(&threadContext->stateMutex);
 	return isPaused;
@@ -285,6 +309,7 @@ int GBAThreadIsPaused(struct GBAThread* threadContext) {
 void GBAThreadTogglePause(struct GBAThread* threadContext) {
 	int frameOn = 1;
 	MutexLock(&threadContext->stateMutex);
+	_waitOnInterrupt(threadContext);
 	if (threadContext->state == THREAD_PAUSED) {
 		threadContext->state = THREAD_RUNNING;
 		ConditionWake(&threadContext->stateCond);

src/gba/gba-thread.h

@@ -10,9 +10,10 @@ typedef void (*ThreadCallback)(struct GBAThread* threadContext);
 enum ThreadState {
 	THREAD_INITIALIZED = -1,
 	THREAD_RUNNING = 0,
-	THREAD_PAUSED = 1,
+	THREAD_INTERRUPTED = 1,
-	THREAD_EXITING = 2,
+	THREAD_PAUSED = 2,
-	THREAD_SHUTDOWN = 3
+	THREAD_EXITING = 3,
+	THREAD_SHUTDOWN = 4
 };
 
 struct GBASync {
@@ -49,6 +50,7 @@ struct GBAThread {
 
 	Mutex stateMutex;
 	Condition stateCond;
+	enum ThreadState savedState;
 
 	GBALogHandler logHandler;
 	ThreadCallback startCallback;
@@ -71,6 +73,9 @@ int GBAThreadHasStarted(struct GBAThread* threadContext);
 void GBAThreadEnd(struct GBAThread* threadContext);
 void GBAThreadJoin(struct GBAThread* threadContext);
 
+void GBAThreadInterrupt(struct GBAThread* threadContext);
+void GBAThreadContinue(struct GBAThread* threadContext);
+
 void GBAThreadPause(struct GBAThread* threadContext);
 void GBAThreadUnpause(struct GBAThread* threadContext);
 int GBAThreadIsPaused(struct GBAThread* threadContext);

src/platform/sdl/sdl-events.c

@@ -55,7 +55,6 @@ static void _pauseAfterFrame(struct GBAThread* context) {
 
 static void _GBASDLHandleKeypress(struct GBAThread* context, struct GBASDLEvents* sdlContext, const struct SDL_KeyboardEvent* event) {
 	enum GBAKey key = 0;
-	int isPaused = GBAThreadIsPaused(context);
 	switch (event->keysym.sym) {
 	case SDLK_z:
 		key = GBA_KEY_A;
@@ -96,13 +95,9 @@ static void _GBASDLHandleKeypress(struct GBAThread* context, struct GBASDLEvents
 		context->sync.audioWait = event->type != SDL_KEYDOWN;
 		return;
 	case SDLK_LEFTBRACKET:
-		if (!isPaused) {
+		GBAThreadInterrupt(context);
-			GBAThreadPause(context);
-		}
 		GBARewind(context, 10);
-		if (!isPaused) {
+		GBAThreadContinue(context);
-			GBAThreadUnpause(context);
-		}
 		return;
 	default:
 		if (event->type == SDL_KEYDOWN) {
@@ -138,13 +133,9 @@ static void _GBASDLHandleKeypress(struct GBAThread* context, struct GBASDLEvents
 				case SDLK_F8:
 				case SDLK_F9:
 				case SDLK_F10:
-					if (!isPaused) {
+					GBAThreadInterrupt(context);
-						GBAThreadPause(context);
-					}
 					GBASaveState(context->gba, event->keysym.sym - SDLK_F1);
-					if (!isPaused) {
+					GBAThreadContinue(context);
-						GBAThreadUnpause(context);
-					}
 					break;
 				default:
 					break;
@@ -161,13 +152,9 @@ static void _GBASDLHandleKeypress(struct GBAThread* context, struct GBASDLEvents
 				case SDLK_F8:
 				case SDLK_F9:
 				case SDLK_F10:
-					if (!isPaused) {
+					GBAThreadInterrupt(context);
-						GBAThreadPause(context);
-					}
 					GBALoadState(context->gba, event->keysym.sym - SDLK_F1);
-					if (!isPaused) {
+					GBAThreadContinue(context);
-						GBAThreadUnpause(context);
-					}
 					break;
 				default:
 					break;