[pull] master from mgba-emu:master

CHANGES

@@ -5,6 +5,7 @@ Features:
  - New option to lock the maximum frame size
  - Memory access and information logging
  - Cheats: Add support for CodeBreaker 5XXXXXXX "Super" codes
+ - Cheats: Add support for additional, undocumented GameShark IF code types
  - 3DS: Add faster "loose" sync mode, default enabled
  - Vita: Allow using rear touch pads as L2/L3/R2/R3
  - Scripting: New `input` API for getting raw keyboard/mouse/controller state

include/mgba/core/cheats.h

@@ -25,6 +25,8 @@ enum mCheatType {
 	CHEAT_IF_NE,
 	CHEAT_IF_LT,
 	CHEAT_IF_GT,
+	CHEAT_IF_LE,
+	CHEAT_IF_GE,
 	CHEAT_IF_ULT,
 	CHEAT_IF_UGT,
 	CHEAT_IF_AND,

include/mgba/internal/gba/cheats.h

@@ -50,11 +50,18 @@ enum GBAGameSharkType {
 	GSA_ASSIGN_LIST = 0x3,
 	GSA_PATCH = 0x6,
 	GSA_BUTTON = 0x8,
-	GSA_IF_EQ = 0xD,
-	GSA_IF_EQ_RANGE = 0xE,
+	GSA_IF = 0xD,
+	GSA_IF_RANGE = 0xE,
 	GSA_HOOK = 0xF
 };
 
+enum GBAGameSharkIfType {
+	GSA_IF_EQ = 0,
+	GSA_IF_NE = 1,
+	GSA_IF_LE = 2,
+	GSA_IF_GE = 3,
+};
+
 enum GBAActionReplay3Condition {
 	PAR3_COND_OTHER = 0x00000000,
 	PAR3_COND_EQ = 0x08000000,

src/core/cheats.c

@@ -713,6 +713,18 @@ void mCheatRefresh(struct mCheatDevice* device, struct mCheatSet* cheats) {
 				negativeConditionRemaining = cheat->negativeRepeat;
 				operationsRemaining = 1;
 				break;
+			case CHEAT_IF_LE:
+				condition = _readMem(device->p, address, cheat->width) <= operand;
+				conditionRemaining = cheat->repeat;
+				negativeConditionRemaining = cheat->negativeRepeat;
+				operationsRemaining = 1;
+				break;
+			case CHEAT_IF_GE:
+				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;

src/gba/cheats/gameshark.c

@@ -51,6 +51,17 @@ static const uint8_t _gsa1T2[256] = {
 };
 
 // http://en.wikipedia.org/wiki/Tiny_Encryption_Algorithm
+void GBACheatEncryptGameShark(uint32_t* op1, uint32_t* op2, const uint32_t* seeds) {
+	uint32_t sum = 0;
+	int i;
+	for (i = 0; i < 32; ++i) {
+		sum += 0x9E3779B9;
+		*op1 += ((*op2 << 4) + seeds[0]) ^ (*op2 + sum) ^ ((*op2 >> 5) + seeds[1]);
+		*op2 += ((*op1 << 4) + seeds[2]) ^ (*op1 + sum) ^ ((*op1 >> 5) + seeds[3]);
+	}
+	sum += 0xC6EF3720;
+}
+
 void GBACheatDecryptGameShark(uint32_t* op1, uint32_t* op2, const uint32_t* seeds) {
 	uint32_t sum = 0xC6EF3720;
 	int i;
@@ -183,17 +194,33 @@ bool GBACheatAddGameSharkRaw(struct GBACheatSet* cheats, uint32_t op1, uint32_t
 			return false;
 		}
 		break;
-	case GSA_IF_EQ:
+	case GSA_IF:
 		if (op1 == 0xDEADFACE) {
 			GBACheatReseedGameShark(cheats->gsaSeeds, op2, _gsa1T1, _gsa1T2);
 			return true;
 		}
 		cheat = mCheatListAppend(&cheats->d.list);
-		cheat->type = CHEAT_IF_EQ;
+		switch (op2 >> 20) {
+		case GSA_IF_EQ:
+			cheat->type = CHEAT_IF_EQ;
+			break;
+		case GSA_IF_NE:
+			cheat->type = CHEAT_IF_NE;
+			break;
+		case GSA_IF_LE:
+			cheat->type = CHEAT_IF_LE;
+			break;
+		case GSA_IF_GE:
+			cheat->type = CHEAT_IF_GE;
+			break;
+		}
 		cheat->width = 2;
+		cheat->repeat = 1;
+		cheat->negativeRepeat = 0;
 		cheat->address = op1 & 0x0FFFFFFF;
-		break;
-	case GSA_IF_EQ_RANGE:
+		cheat->operand = op2 & 0xFFFF;
+		return true;
+	case GSA_IF_RANGE:
 		cheat = mCheatListAppend(&cheats->d.list);
 		cheat->type = CHEAT_IF_EQ;
 		cheat->width = 2;
@@ -291,14 +318,14 @@ int GBACheatGameSharkProbability(uint32_t op1, uint32_t op2) {
 	case GSA_BUTTON:
 		probability += 0x10;
 		break;
-	case GSA_IF_EQ:
+	case GSA_IF:
 		probability += 0x20;
-		if (op2 & 0xFFFF0000) {
+		if (op2 & 0xFFCF0000) {
 			probability -= 0x10;
 		}
 		probability += GBACheatAddressIsReal(address);
 		break;
-	case GSA_IF_EQ_RANGE:
+	case GSA_IF_RANGE:
 		probability += 0x20;
 		probability += GBACheatAddressIsReal(op2);
 		if (op1 & 0x0F000000) {

src/gba/cheats/gameshark.h

@@ -21,6 +21,7 @@ enum GBACheatGameSharkVersion {
 };
 
 struct GBACheatSet;
+void GBACheatEncryptGameShark(uint32_t* op1, uint32_t* op2, const uint32_t* seeds);
 void GBACheatDecryptGameShark(uint32_t* op1, uint32_t* op2, const uint32_t* seeds);
 void GBACheatReseedGameShark(uint32_t* seeds, uint16_t params, const uint8_t* t1, const uint8_t* t2);
 void GBACheatSetGameSharkVersion(struct GBACheatSet* cheats, enum GBACheatGameSharkVersion version);