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GB Cheats: Add check byte to GameGenie codes

This commit is contained in:
Jeffrey Pfau 2016-09-01 02:34:04 -07:00
parent d05f513a17
commit 6519c4e465
2 changed files with 27 additions and 2 deletions
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28
src/gb/cheats.c
View File

@ -21,7 +21,13 @@ static void _patchROM(struct mCheatDevice* device, struct GBCheatSet* cheats) {
if (patch->applied) {
continue;
}
// TODO: Byte check
if (patch->checkByte) {
// TODO: All segments
int8_t value = GBView8(device->p->cpu, patch->address, 0);
if (value != patch->oldValue) {
continue;
}
}
GBPatch8(device->p->cpu, patch->address, patch->newValue, &patch->oldValue);
patch->applied = true;
}
@ -37,7 +43,7 @@ static void _unpatchROM(struct mCheatDevice* device, struct GBCheatSet* cheats)
if (!patch->applied) {
continue;
}
GBPatch8(device->p->cpu, patch->address, patch->oldValue, NULL);
GBPatch8(device->p->cpu, patch->address, patch->oldValue, &patch->newValue);
patch->applied = false;
}
}
@ -120,6 +126,7 @@ static bool GBCheatAddGameSharkLine(struct GBCheatSet* cheats, const char* line)
static bool GBCheatAddGameGenieLine(struct GBCheatSet* cheats, const char* line) {
uint16_t op1;
uint16_t op2;
uint16_t op3 = 0x1000;
const char* lineNext = hex12(line, &op1);
if (!lineNext || lineNext[0] != '-') {
return false;
@ -129,6 +136,13 @@ static bool GBCheatAddGameGenieLine(struct GBCheatSet* cheats, const char* line)
if (!lineNext) {
return false;
}
if (lineNext[0] == '-') {
++lineNext;
lineNext = hex12(lineNext, &op3);
}
if (!lineNext || lineNext[0]) {
return false;
}
uint16_t address = (op1 & 0xF) << 8;
address |= (op2 >> 4) & 0xFF;
address |= ((op2 & 0xF) ^ 0xF) << 12;
@ -136,6 +150,16 @@ static bool GBCheatAddGameGenieLine(struct GBCheatSet* cheats, const char* line)
patch->address = address;
patch->newValue = op1 >> 4;
patch->applied = false;
if (op3 < 0x1000) {
uint32_t value = ((op3 & 0xF00) << 20) | (op3 & 0xF);
value = ROR(value, 2);
value |= value >> 24;
value ^= 0xBA;
patch->oldValue = value;
patch->checkByte = true;
} else {
patch->checkByte = false;
}
return true;
}

1
src/gb/cheats.h
View File

@ -23,6 +23,7 @@ struct GBCheatPatch {
int8_t newValue;
int8_t oldValue;
bool applied;
bool checkByte;
};
DECLARE_VECTOR(GBCheatPatchList, struct GBCheatPatch);