Savestate: Don't break event callbacks when a save fails

CoreTiming::DoState replaced every event's callback with the anti-crash
one in every mode, relying on each module's restore to put it back. A save
that failed partway never got to those, and left the running game with
events that break into the debugger. The missing-section fallbacks then
also ran on the save: cheats and the mic re-registered events into the
wrong slots, and achievements reset the runtime.

Co-Authored-By: Claude Opus 5.5 (1M context) <[email protected]>

Core/CoreTiming.cpp

@@ -544,13 +544,17 @@ void DoState(PointerWrap &p) {
 		return;
 	}
 
-	// These (should) be filled in later by the modules.
-	for (int i = 0; i < current; ++i) {
-		event_types[i].callback = AntiCrashCallback;
-		event_types[i].name = "INVALID EVENT";
+	// These (should) be filled in later by the modules. Only when loading: a save that fails partway
+	// wouldn't get to all the restores, and would leave the running game with broken events.
+	if (p.mode == PointerWrap::MODE_READ) {
+		for (int i = 0; i < current; ++i) {
+			event_types[i].callback = AntiCrashCallback;
+			event_types[i].name = "INVALID EVENT";
+		}
+		nextEventTypeRestoreId = n - 1;
+		usedEventTypes.clear();
 	}
-	nextEventTypeRestoreId = n - 1;
-	usedEventTypes.clear();
+	// Needed in every pass, or each restore would look like a duplicate and get a new id.
 	restoredEventTypes.clear();
 
 	if (s >= 3) {

Core/CwCheat.cpp

@@ -270,10 +270,13 @@ void __CheatDoState(PointerWrap &p) {
 		// CoreTiming::DoState has already replaced the queue with the state's, which has no cheat
 		// event in it, so without scheduling one here hleCheat never runs again and cheats (plus
 		// the enable/disable polling) stay dead for the rest of the session.
-		CheatEvent = -1;
-		CoreTiming::RestoreRegisterEvent(CheatEvent, "CheatEvent", &hleCheat);
-		CoreTiming::RemoveEvent(CheatEvent);
-		CoreTiming::ScheduleEvent(msToCycles(GetRefreshMs()), CheatEvent, 0);
+		// (Not when a save failed earlier and every section after comes back missing.)
+		if (p.mode == PointerWrap::MODE_READ) {
+			CheatEvent = -1;
+			CoreTiming::RestoreRegisterEvent(CheatEvent, "CheatEvent", &hleCheat);
+			CoreTiming::RemoveEvent(CheatEvent);
+			CoreTiming::ScheduleEvent(msToCycles(GetRefreshMs()), CheatEvent, 0);
+		}
 		return;
 	}
 

Core/HLE/sceUsbMic.cpp

@@ -121,10 +121,12 @@ void __UsbMicShutdown() {
 void __UsbMicDoState(PointerWrap &p) {
 	auto s = p.Section("sceUsbMic", 0, 3);
 	if (!s) {
-		// Still need to restore the event.
-		eventMicBlockingResume = -1;
-		CoreTiming::RestoreRegisterEvent(eventMicBlockingResume, "MicBlockingResume", &__MicBlockingResume);
-		waitingThreads.clear();
+		// Still need to restore the event (unless this is a save that failed earlier.)
+		if (p.mode == p.MODE_READ) {
+			eventMicBlockingResume = -1;
+			CoreTiming::RestoreRegisterEvent(eventMicBlockingResume, "MicBlockingResume", &__MicBlockingResume);
+			waitingThreads.clear();
+		}
 		return;
 	}
 	bool isMicStartedNow = Microphone::isMicStarted();

Core/RetroAchievements.cpp

@@ -877,7 +877,10 @@ void Idle() {
 void DoState(PointerWrap &p) {
 	auto sw = p.Section("Achievements", 0, 1);
 	if (!sw) {
-		// Save state is missing the section.
+		// Save state is missing the section, or this is a save that failed earlier.
+		if (p.mode != PointerWrap::MODE_READ) {
+			return;
+		}
 		// Reset the runtime.
 		if (HasAchievementsOrLeaderboards()) {
 			auto ac = GetI18NCategory(I18NCat::ACHIEVEMENTS);