Qt: Add savestate save undo

CHANGES

@@ -24,7 +24,7 @@ Features:
  - Preliminary support for yanking out the game pak while a game is running
  - Thumb-drive mode by putting a file called portable.ini in the same folder
  - Configurable display driver, between software and OpenGL
- - Undo-able savestate loading
+ - Undo-able savestate loading and saving
 Bugfixes:
  - ARM7: Fix SWI and IRQ timings
  - GBA Audio: Force audio FIFOs to 32-bit

src/platform/qt/GameController.cpp

@@ -581,6 +581,12 @@ void GameController::saveState(int slot) {
 	}
 	GBARunOnThread(&m_threadContext, [](GBAThread* context) {
 		GameController* controller = static_cast<GameController*>(context->userData);
+		VFile* vf = GBAGetState(context->gba, context->stateDir, controller->m_stateSlot, false);
+		if (vf) {
+			controller->m_backupSaveState.resize(vf->size(vf));
+			vf->read(vf, controller->m_backupSaveState.data(), controller->m_backupSaveState.size());
+			vf->close(vf);
+		}
 		GBASaveState(context, context->stateDir, controller->m_stateSlot, true);
 	});
 }
@@ -602,6 +608,23 @@ void GameController::loadBackupState() {
 	});
 }
 
+void GameController::saveBackupState() {
+	if (m_backupSaveState.isEmpty()) {
+		return;
+	}
+
+	GBARunOnThread(&m_threadContext, [](GBAThread* context) {
+		GameController* controller = static_cast<GameController*>(context->userData);
+		VFile* vf = GBAGetState(context->gba, context->stateDir, controller->m_stateSlot, true);
+		if (vf) {
+			vf->write(vf, controller->m_backupSaveState.constData(), controller->m_backupSaveState.size());
+			vf->close(vf);
+			GBALog(context->gba, GBA_LOG_STATUS, "Undid state save");
+		}
+		controller->m_backupSaveState.clear();
+	});
+}
+
 void GameController::setVideoSync(bool set) {
 	m_videoSync = set;
 	if (!m_turbo) {

src/platform/qt/GameController.h

@@ -121,6 +121,7 @@ public slots:
 	void loadState(int slot = 0);
 	void saveState(int slot = 0);
 	void loadBackupState();
+	void saveBackupState();
 	void setVideoSync(bool);
 	void setAudioSync(bool);
 	void setFrameskip(int);
@@ -194,7 +195,7 @@ private:
 
 	int m_stateSlot;
 	GBASerializedState* m_backupLoadState;
-	GBASerializedState* m_backupSaveState; // TODO: Use this
+	QByteArray m_backupSaveState;
 
 	InputController* m_inputController;
 	MultiplayerController* m_multiplayer;

src/platform/qt/Window.cpp

@@ -707,6 +707,12 @@ void Window::setupMenu(QMenuBar* menubar) {
 	m_gameActions.append(undoLoadState);
 	addControlledAction(quickLoadMenu, undoLoadState, "undoLoadState");
 
+	QAction* undoSaveState = new QAction(tr("Undo save state"), quickSaveMenu);
+	undoSaveState->setShortcut(tr("Shift+F11"));
+	connect(undoSaveState, SIGNAL(triggered()), m_controller, SLOT(saveBackupState()));
+	m_gameActions.append(undoSaveState);
+	addControlledAction(quickLoadMenu, undoSaveState, "undoSaveState");
+
 	quickLoadMenu->addSeparator();
 	quickSaveMenu->addSeparator();