77 lines
2.7 KiB
Python
77 lines
2.7 KiB
Python
import binascii
|
|
import Utils
|
|
|
|
b2h = binascii.hexlify
|
|
h2b = binascii.unhexlify
|
|
|
|
|
|
class ROM:
|
|
def __init__(self, filename):
|
|
data = open(Utils.local_path(filename), "rb").read()
|
|
#assert len(data) == 1024 * 1024
|
|
self.banks = []
|
|
for n in range(0x40):
|
|
self.banks.append(bytearray(data[n*0x4000:(n+1)*0x4000]))
|
|
|
|
def patch(self, bank_nr, addr, old, new, *, fill_nop=False):
|
|
new = h2b(new)
|
|
bank = self.banks[bank_nr]
|
|
if old is not None:
|
|
if isinstance(old, int):
|
|
old = bank[addr:old]
|
|
else:
|
|
old = h2b(old)
|
|
if fill_nop:
|
|
assert len(old) >= len(new), "Length mismatch: %d != %d (%s != %s)" % (len(old), len(new), b2h(old), b2h(new))
|
|
new += b'\x00' * (len(old) - len(new))
|
|
else:
|
|
assert len(old) == len(new), "Length mismatch: %d != %d (%s != %s)" % (len(old), len(new), b2h(old), b2h(new))
|
|
assert addr >= 0 and addr + len(old) <= 16*1024
|
|
if bank[addr:addr+len(old)] != old:
|
|
if bank[addr:addr + len(old)] == new:
|
|
# Patch is already applied.
|
|
return
|
|
loc = bank.find(old)
|
|
while loc > -1:
|
|
print("Possible at:", hex(loc))
|
|
loc = bank.find(old, loc+1)
|
|
assert False, "Patch mismatch:\n%s !=\n%s at 0x%04x" % (b2h(bank[addr:addr+len(old)]), b2h(old), addr)
|
|
bank[addr:addr+len(new)] = new
|
|
assert len(bank) == 0x4000
|
|
|
|
def fixHeader(self, *, name=None):
|
|
if name is not None:
|
|
name = name.encode("utf-8")
|
|
name = (name + (b"\x00" * 15))[:15]
|
|
self.banks[0][0x134:0x143] = name
|
|
|
|
checksum = 0
|
|
for c in self.banks[0][0x134:0x14D]:
|
|
checksum -= c + 1
|
|
self.banks[0][0x14D] = checksum & 0xFF
|
|
|
|
# zero out the checksum before calculating it.
|
|
self.banks[0][0x14E] = 0
|
|
self.banks[0][0x14F] = 0
|
|
checksum = 0
|
|
for bank in self.banks:
|
|
checksum = (checksum + sum(bank)) & 0xFFFF
|
|
self.banks[0][0x14E] = checksum >> 8
|
|
self.banks[0][0x14F] = checksum & 0xFF
|
|
|
|
def save(self, file, *, name=None):
|
|
# don't pass the name to fixHeader
|
|
self.fixHeader()
|
|
if isinstance(file, str):
|
|
f = open(file, "wb")
|
|
for bank in self.banks:
|
|
f.write(bank)
|
|
f.close()
|
|
print("Saved:", file)
|
|
else:
|
|
for bank in self.banks:
|
|
file.write(bank)
|
|
|
|
def readHexSeed(self):
|
|
return self.banks[0x3E][0x2F00:0x2F10].hex().upper()
|