GBA Cheats: Fix PARv3 multiline blocks (fixes #889)

CHANGES

@@ -30,6 +30,7 @@ Bugfixes:
  - GBA I/O: Fix reading from a few invalid I/O registers (fixes mgba.io/i/876)
  - GBA Savedata: Fix size of SRAM saves (fixes mgba.io/i/883)
  - GB Video: Fix read mode when enabling LCD
+ - GBA Cheats: Fix PARv3 multiline blocks (fixes mgba.io/i/889)
 Misc:
  - Qt: Don't rebuild library view if style hasn't changed
  - SDL: Fix 2.0.5 build on macOS under some circumstances

src/core/cheats.c

@@ -256,35 +256,23 @@ void mCheatRefresh(struct mCheatDevice* device, struct mCheatSet* cheats) {
 	if (!cheats->enabled) {
 		return;
 	}
-	bool condition = true;
-	int conditionRemaining = 0;
-	int negativeConditionRemaining = 0;
 	cheats->refresh(cheats, device);
 
+	size_t elseLoc = 0;
+	size_t endLoc = 0;
 	size_t nCodes = mCheatListSize(&cheats->list);
 	size_t i;
 	for (i = 0; i < nCodes; ++i) {
-		if (conditionRemaining > 0) {
-			--conditionRemaining;
-			if (!condition) {
-				continue;
-			}
-		} else if (negativeConditionRemaining > 0) {
-			conditionRemaining = negativeConditionRemaining - 1;
-			negativeConditionRemaining = 0;
-			condition = !condition;
-			if (!condition) {
-				continue;
-			}
-		} else {
-			condition = true;
-		}
 		struct mCheat* cheat = mCheatListGetPointer(&cheats->list, i);
 		int32_t value = 0;
 		int32_t operand = cheat->operand;
 		uint32_t operationsRemaining = cheat->repeat;
 		uint32_t address = cheat->address;
 		bool performAssignment = false;
+		bool condition = true;
+		int conditionRemaining = 0;
+		int negativeConditionRemaining = 0;
+
 		for (; operationsRemaining; --operationsRemaining) {
 			switch (cheat->type) {
 			case CHEAT_ASSIGN:
@@ -312,46 +300,55 @@ void mCheatRefresh(struct mCheatDevice* device, struct mCheatSet* cheats) {
 				condition = _readMem(device->p, address, cheat->width) == operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_NE:
 				condition = _readMem(device->p, address, cheat->width) != operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_LT:
 				condition = _readMem(device->p, address, cheat->width) < operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_GT:
 				condition = _readMem(device->p, address, cheat->width) > operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_ULT:
 				condition = (uint32_t) _readMem(device->p, address, cheat->width) < (uint32_t) operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_UGT:
 				condition = (uint32_t) _readMem(device->p, address, cheat->width) > (uint32_t) operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_AND:
 				condition = _readMem(device->p, address, cheat->width) & operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_LAND:
 				condition = _readMem(device->p, address, cheat->width) && operand;
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			case CHEAT_IF_NAND:
 				condition = !(_readMem(device->p, address, cheat->width) & operand);
 				conditionRemaining = cheat->repeat;
 				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
 				break;
 			}
 
@@ -362,6 +359,18 @@ void mCheatRefresh(struct mCheatDevice* device, struct mCheatSet* cheats) {
 			address += cheat->addressOffset;
 			operand += cheat->operandOffset;
 		}
+
+
+		if (elseLoc && i == elseLoc) {
+			i = endLoc;
+			endLoc = 0;
+		}
+		if (conditionRemaining > 0 && !condition) {
+			i += conditionRemaining;
+		} else if (negativeConditionRemaining > 0) {
+			elseLoc = i + conditionRemaining;
+			endLoc = elseLoc + negativeConditionRemaining;
+		}
 	}
 }
 

src/gba/cheats/parv3.c

@@ -53,7 +53,7 @@ static uint32_t _parAddr(uint32_t x) {
 }
 
 static void _parEndBlock(struct GBACheatSet* cheats) {
-	size_t size = mCheatListSize(&cheats->d.list) - cheats->currentBlock;
+	size_t size = mCheatListSize(&cheats->d.list) - cheats->currentBlock - 1;
 	struct mCheat* currentBlock = mCheatListGetPointer(&cheats->d.list, cheats->currentBlock);
 	if (currentBlock->repeat) {
 		currentBlock->negativeRepeat = size - currentBlock->repeat;
@@ -64,7 +64,7 @@ static void _parEndBlock(struct GBACheatSet* cheats) {
 }
 
 static void _parElseBlock(struct GBACheatSet* cheats) {
-	size_t size = mCheatListSize(&cheats->d.list) - cheats->currentBlock;
+	size_t size = mCheatListSize(&cheats->d.list) - cheats->currentBlock - 1;
 	struct mCheat* currentBlock = mCheatListGetPointer(&cheats->d.list, cheats->currentBlock);
 	currentBlock->repeat = size;
 }