ld: minor refactoring

This commit is contained in:
CPunch 2022-08-19 15:46:47 -05:00
parent 3be45f156a
commit f9f1d4af00

View File

@ -70,6 +70,8 @@ _RKBCInstr = [Opcodes.SETTABLE, Opcodes.ADD, Opcodes.SUB, Opcodes.MUL, Opcodes.D
_RKCInstr = [Opcodes.GETTABLE, Opcodes.SELF]
_KBx = [Opcodes.LOADK, Opcodes.GETGLOBAL, Opcodes.SETGLOBAL]
_LUAMAGIC = b'\x1bLua'
# is an 'RK' value a K? (result is true for K, false for R)
def whichRK(rk: int):
return (rk & (1 << 8)) > 0
@ -313,29 +315,21 @@ class LuaUndump:
def get_byte(self) -> int:
return self.loadBlock(1)[0]
def get_int32(self) -> int:
if (self.big_endian):
return int.from_bytes(self.loadBlock(4), byteorder='big', signed=False)
else:
return int.from_bytes(self.loadBlock(4), byteorder='little', signed=False)
def get_uint32(self) -> int:
order = 'big' if self.big_endian else 'little'
return int.from_bytes(self.loadBlock(4), byteorder=order, signed=False)
def get_int(self) -> int:
if (self.big_endian):
return int.from_bytes(self.loadBlock(self.int_size), byteorder='big', signed=False)
else:
return int.from_bytes(self.loadBlock(self.int_size), byteorder='little', signed=False)
def get_uint(self) -> int:
order = 'big' if self.big_endian else 'little'
return int.from_bytes(self.loadBlock(self.int_size), byteorder=order, signed=False)
def get_size_t(self) -> int:
if (self.big_endian):
return int.from_bytes(self.loadBlock(self.size_t), byteorder='big', signed=False)
else:
return int.from_bytes(self.loadBlock(self.size_t), byteorder='little', signed=False)
order = 'big' if self.big_endian else 'little'
return int.from_bytes(self.loadBlock(self.size_t), byteorder=order, signed=False)
def get_double(self) -> int:
if self.big_endian:
return struct.unpack('>d', self.loadBlock(8))[0]
else:
return struct.unpack('<d', self.loadBlock(8))[0]
order = '>d' if self.big_endian else '<d'
return struct.unpack(order, self.loadBlock(8))[0]
def get_string(self, size) -> str:
if (size == None):
@ -349,8 +343,8 @@ class LuaUndump:
chunk = Chunk()
chunk.name = self.get_string(None)
chunk.frst_line = self.get_int()
chunk.last_line = self.get_int()
chunk.frst_line = self.get_uint()
chunk.last_line = self.get_uint()
chunk.numUpvals = self.get_byte()
chunk.numParams = self.get_byte()
@ -361,12 +355,12 @@ class LuaUndump:
chunk.name = chunk.name[1:-1]
# parse instructions
num = self.get_int()
num = self.get_uint()
for i in range(num):
chunk.appendInstruction(_decode_instr(self.get_int32()))
chunk.appendInstruction(_decode_instr(self.get_uint32()))
# get constants
num = self.get_int()
num = self.get_uint()
for i in range(num):
constant: Constant = None
type = self.get_byte()
@ -385,7 +379,7 @@ class LuaUndump:
chunk.appendConstant(constant)
# parse protos
num = self.get_int()
num = self.get_uint()
for i in range(num):
chunk.appendProto(self.decode_chunk())
@ -393,20 +387,20 @@ class LuaUndump:
# eh, for now just consume the bytes.
# line numbers
num = self.get_int()
num = self.get_uint()
for i in range(num):
self.get_int()
self.get_uint()
# locals
num = self.get_int()
num = self.get_uint()
for i in range(num):
name = self.get_string(None)[:-1] # local name ([:-1] to remove the NULL terminator)
start = self.get_int() # local start PC
end = self.get_int() # local end PC
start = self.get_uint() # local start PC
end = self.get_uint() # local end PC
chunk.appendLocal(Local(name, start, end))
# upvalues
num = self.get_int()
num = self.get_uint()
for i in range(num):
self.get_string(None) # upvalue name
@ -414,18 +408,18 @@ class LuaUndump:
def decode_rawbytecode(self, rawbytecode):
# bytecode sanity checks
if not rawbytecode[0:4] == b'\x1bLua':
if not rawbytecode[0:4] == _LUAMAGIC:
raise Exception("Lua Bytecode expected!")
bytecode = array.array('b', rawbytecode)
return self.decode_bytecode(bytecode)
def decode_bytecode(self, bytecode):
self.bytecode = bytecode
self.bytecode = bytecode
# aligns index, skips header
self.index = 4
self.vm_version = self.get_byte()
self.bytecode_format = self.get_byte()
self.big_endian = (self.get_byte() == 0)