void GBASavedataMask(struct GBASavedata* savedata, struct VFile* vf, bool writeback) {
enum SavedataType type = savedata->type;
GBASavedataDeinit(savedata);
savedata->vf = vf;
savedata->mapMode = MAP_READ;
savedata->maskWriteback = writeback;
GBASavedataForceType(savedata, type, savedata->realisticTiming);
}
void GBASavedataMask(struct GBASavedata* savedata, struct VFile* vf, bool writeback) {
enum SavedataType type = savedata->type;
struct VFile* oldVf = savedata->vf;
GBASavedataDeinit(savedata);
if (oldVf && oldVf != savedata->realVf) {
oldVf->close(oldVf);
}
savedata->vf = vf;
savedata->mapMode = MAP_READ;
savedata->maskWriteback = writeback;
GBASavedataForceType(savedata, type);
}
void GBASavedataUnmask(struct GBASavedata* savedata) {
if (!savedata->realVf || savedata->vf == savedata->realVf) {
return;
}
enum SavedataType type = savedata->type;
struct VFile* vf = savedata->vf;
GBASavedataDeinit(savedata);
savedata->vf = savedata->realVf;
savedata->mapMode = MAP_WRITE;
GBASavedataForceType(savedata, type);
if (savedata->maskWriteback) {
GBASavedataLoad(savedata, vf);
savedata->maskWriteback = false;
}
vf->close(vf);
}
bool GBASavedataImportSharkPort(struct GBA* gba, struct VFile* vf, bool testChecksum) {
union {
char c[0x1C];
int32_t i;
} buffer;
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
int32_t size;
LOAD_32(size, 0, &buffer.i);
if (size != (int32_t) strlen(SHARKPORT_HEADER)) {
return false;
}
if (vf->read(vf, buffer.c, size) < size) {
return false;
}
if (memcmp(SHARKPORT_HEADER, buffer.c, size) != 0) {
return false;
}
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
LOAD_32(size, 0, &buffer.i);
if (size != 0x000F0000) {
// What is this value?
return false;
}
// Skip first three fields
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
LOAD_32(size, 0, &buffer.i);
if (vf->seek(vf, size, SEEK_CUR) < 0) {
return false;
}
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
LOAD_32(size, 0, &buffer.i);
if (vf->seek(vf, size, SEEK_CUR) < 0) {
return false;
}
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
LOAD_32(size, 0, &buffer.i);
if (vf->seek(vf, size, SEEK_CUR) < 0) {
return false;
}
// Read payload
if (vf->read(vf, &buffer.i, 4) < 4) {
return false;
}
LOAD_32(size, 0, &buffer.i);
if (size < 0x1C || size > SIZE_CART_FLASH1M + 0x1C) {
return false;
}
char* payload = malloc(size);
if (vf->read(vf, payload, size) < size) {
goto cleanup;
}
struct GBACartridge* cart = (struct GBACartridge*) gba->memory.rom;
memcpy(buffer.c, &cart->title, 16);
buffer.c[0x10] = 0;
buffer.c[0x11] = 0;
buffer.c[0x12] = cart->checksum;
buffer.c[0x13] = cart->maker;
buffer.c[0x14] = 1;
buffer.c[0x15] = 0;
buffer.c[0x16] = 0;
buffer.c[0x17] = 0;
buffer.c[0x18] = 0;
buffer.c[0x19] = 0;
buffer.c[0x1A] = 0;
buffer.c[0x1B] = 0;
if (memcmp(buffer.c, payload, 0x1C) != 0) {
goto cleanup;
}
uint32_t checksum;
if (vf->read(vf, &buffer.i, 4) < 4) {
goto cleanup;
}
LOAD_32(checksum, 0, &buffer.i);
if (testChecksum) {
uint32_t calcChecksum = 0;
int i;
for (i = 0; i < size; ++i) {
calcChecksum += ((int32_t) payload[i]) << (calcChecksum % 24);
}
if (calcChecksum != checksum) {
goto cleanup;
}
}
uint32_t copySize = size - 0x1C;
switch (gba->memory.savedata.type) {
case SAVEDATA_SRAM:
if (copySize > SIZE_CART_SRAM) {
copySize = SIZE_CART_SRAM;
}
break;
case SAVEDATA_FLASH512:
if (copySize > SIZE_CART_FLASH512) {
GBASavedataForceType(&gba->memory.savedata, SAVEDATA_FLASH1M, gba->memory.savedata.realisticTiming);
}
// Fall through
case SAVEDATA_FLASH1M:
if (copySize > SIZE_CART_FLASH1M) {
copySize = SIZE_CART_FLASH1M;
}
break;
case SAVEDATA_EEPROM:
if (copySize > SIZE_CART_EEPROM) {
copySize = SAVEDATA_EEPROM;
}
break;
case SAVEDATA_FORCE_NONE:
case SAVEDATA_AUTODETECT:
goto cleanup;
}
memcpy(gba->memory.savedata.data, &payload[0x1C], copySize);
free(payload);
return true;
cleanup:
free(payload);
return false;
}
