[macOS] Fix running with `DisplayServerHeadless`.

platform/macos/display_server_macos.h

@@ -64,7 +64,7 @@
 #undef CursorShape
 
 class DisplayServerMacOS : public DisplayServer {
-	// No need to register with GDCLASS, it's platform-specific and nothing is added.
+	GDCLASS(DisplayServerMacOS, DisplayServer); // Note: required for Object::cast_to.
 
 	_THREAD_SAFE_CLASS_
 

platform/macos/godot_application.mm

@@ -81,7 +81,7 @@
 		} break;
 	}
 
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds && keycode != Key::NONE) {
 		DisplayServerMacOS::KeyEvent ke;
 
@@ -109,7 +109,7 @@
 		[self mediaKeyEvent:keyCode state:keyState repeat:keyRepeat];
 	}
 
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds) {
 		if ([event type] == NSEventTypeLeftMouseDown || [event type] == NSEventTypeRightMouseDown || [event type] == NSEventTypeOtherMouseDown) {
 			if (ds->mouse_process_popups()) {

platform/macos/godot_application_delegate.mm

@@ -48,7 +48,7 @@
 - (void)searchForItemsWithSearchString:(NSString *)searchString resultLimit:(NSInteger)resultLimit matchedItemHandler:(void (^)(NSArray *items))handleMatchedItems {
 	NSMutableArray *found_items = [[NSMutableArray alloc] init];
 
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds && ds->_help_get_search_callback().is_valid()) {
 		Callable cb = ds->_help_get_search_callback();
 
@@ -77,7 +77,7 @@
 }
 
 - (void)performActionForItem:(id)item {
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds && ds->_help_get_action_callback().is_valid()) {
 		Callable cb = ds->_help_get_action_callback();
 
@@ -118,7 +118,7 @@
 }
 
 - (void)system_theme_changed:(NSNotification *)notification {
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds) {
 		ds->emit_system_theme_changed();
 	}
@@ -199,7 +199,7 @@
 }
 
 - (void)applicationDidResignActive:(NSNotification *)notification {
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds) {
 		ds->mouse_process_popups(true);
 	}
@@ -215,7 +215,7 @@
 }
 
 - (void)globalMenuCallback:(id)sender {
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds) {
 		return ds->menu_callback(sender);
 	}
@@ -239,7 +239,7 @@
 }
 
 - (NSApplicationTerminateReply)applicationShouldTerminate:(NSApplication *)sender {
-	DisplayServerMacOS *ds = (DisplayServerMacOS *)DisplayServer::get_singleton();
+	DisplayServerMacOS *ds = Object::cast_to<DisplayServerMacOS>(DisplayServer::get_singleton());
 	if (ds && ds->has_window(DisplayServerMacOS::MAIN_WINDOW_ID)) {
 		ds->send_window_event(ds->get_window(DisplayServerMacOS::MAIN_WINDOW_ID), DisplayServerMacOS::WINDOW_EVENT_CLOSE_REQUEST);
 	}

platform/macos/os_macos.h

@@ -46,6 +46,7 @@ class OS_MacOS : public OS_Unix {
 
 	id delegate = nullptr;
 	bool should_terminate = false;
+	bool main_stared = false;
 
 	JoypadApple *joypad_apple = nullptr;
 

platform/macos/os_macos.mm

@@ -51,8 +51,13 @@ void OS_MacOS::pre_wait_observer_cb(CFRunLoopObserverRef p_observer, CFRunLoopAc
 
 	@autoreleasepool {
 		@try {
-			if (DisplayServer::get_singleton()) {
-				static_cast<DisplayServerMacOS *>(DisplayServer::get_singleton())->_process_events(false); // Get rid of pending events.
+			// Get rid of pending events.
+			DisplayServer *ds = DisplayServer::get_singleton();
+			DisplayServerMacOS *ds_mac = Object::cast_to<DisplayServerMacOS>(ds);
+			if (ds_mac) {
+				ds_mac->_process_events(false);
+			} else if (ds) {
+				ds->process_events();
 			}
 			os->joypad_apple->process_joypads();
 
@@ -839,6 +844,8 @@ void OS_MacOS::start_main() {
 	}
 
 	if (err == OK) {
+		main_stared = true;
+
 		int ret;
 		@autoreleasepool {
 			ret = Main::start();
@@ -883,8 +890,10 @@ void OS_MacOS::cleanup() {
 	if (main_loop) {
 		main_loop->finalize();
 	}
-	@autoreleasepool {
-		Main::cleanup();
+	if (main_stared) {
+		@autoreleasepool {
+			Main::cleanup();
+		}
 	}
 }