from gbz80disasm import opt_table, end_08_scripts_with, relative_jumps, relative_unconditional_jumps, call_commands from ctypes import c_int8 from copy import copy, deepcopy class RomStr(str): """ Simple wrapper to prevent a giant rom from being shown on screen. """ def __repr__(self): """ Simplifies this object so that the output doesn't overflow stdout. """ return "RomStr(too long)" @classmethod def load(cls, crystal=True, red=False): """ Loads a ROM into a RomStr. """ if crystal and not red: file_handler = open("../baserom.gbc", "r") elif red and not crystal: file_handler = open("../pokered-baserom.gbc", "r") else: raise Exception, "not sure which rom to load?" bytes = file_handler.read() file_handler.close() return RomStr(bytes) def length(self): """ len(self) """ return len(self) def len(self): """ len(self) """ return self.length() def interval(self, offset, length, strings=True, debug=True): """ returns hex values for the rom starting at offset until offset+length """ returnable = [] for byte in self[offset:offset+length]: if strings: returnable.append(hex(ord(byte))) else: returnable.append(ord(byte)) return returnable def until(self, offset, byte, strings=True, debug=False): """ Returns hex values from rom starting at offset until the given byte. """ return self.interval(offset, self.find(chr(byte), offset) - offset, strings=strings) def to_asm(self, address, end_address=None, size=None, max_size=0x4000, debug=None): """ Disassembles ASM at some address. This will stop disassembling when either the end_address or size is met. Also, there's a maximum size that will be parsed, so that large patches of data aren't parsed as code. """ start_address = address if start_address == None: raise Exception, "address must be given" if debug == None: if not hasattr(self, "debug"): debug = False else: debug = self.debug # this is probably a terrible idea.. why am i doing this? if size != None and max_size < size: raise Exception, "max_size must be greater than or equal to size" elif end_address != None and (end_address - start_address) > max_size: raise Exception, "end_address is out of bounds" elif end_address != None and size != None: if (end_address - start_address) >= size: size = end_address - start_address else: end_address = start_address + size elif end_address == None and size != None: end_address = start_address + size elif end_address != None and size == None: size = end_address - start_address return Asm(start_address=start_address, end_address=end_address, size=size, max_size=max_size, debug=debug, rom=self) class Asm: """ z80 disassembler """ def __init__(self, start_address=None, end_address=None, size=None, max_size=0x4000, debug=True, rom=None): assert start_address != None, "start_address must be given" if rom == None: file_handler = open("../baserom.gbc", "r") bytes = file_handler.read() file_handler.close() rom = RomStr(bytes) if debug not in [None, True, False]: raise Exception, "debug param is invalid" if debug == None: debug = False # get end_address and size in sync with each other if end_address == None and size != None: end_address = start_address + size elif end_address != None and size == None: size = end_address - start_address elif end_address != None and size != None: size = max(end_address - start_address, size) end_address = start_address + size # check that the bounds make sense if end_address != None: if end_address <= start_address: raise Exception, "end_address is out of bounds" elif (end_address - start_address) > max_size: raise Exception, "end_address goes beyond max_size" # check more edge cases if not start_address >= 0: raise Exception, "start_address must be at least 0" elif end_address != None and not end_address >= 0: raise Exception, "end_address must be at least 0" self.rom = rom self.start_address = start_address self.end_address = end_address self.size = size self.max_size = max_size self.debug = debug self.parse() def parse(self): """ Disassembles stuff and things. """ rom = self.rom start_address = self.start_address end_address = self.end_address max_size = self.max_size debug = self.debug bank_id = start_address / 0x4000 # [{"command": 0x20, "bytes": [0x20, 0x40, 0x50], # "asm": "jp $5040", "label": "Unknown5040"}] asm_commands = {} offset = start_address last_hl_address = None last_a_address = None used_3d97 = False keep_reading = True while (end_address != 0 and offset <= end_address) or keep_reading: # read the current opcode byte current_byte = ord(rom[offset]) current_byte_number = len(asm_commands.keys()) # setup this next/upcoming command if offset in asm_commands.keys(): asm_command = asm_commands[offset] else: asm_command = {} asm_command["address"] = offset if not "references" in asm_command.keys(): # This counts how many times relative jumps reference this # byte. This is used to determine whether or not to print out a # label later. asm_command["references"] = 0 print "debug1" # some commands have two opcodes next_byte = ord(rom[offset+1]) print "offset: \t\t" + hex(offset) print "current_byte: \t\t" + hex(current_byte) print "next_byte: \t\t" + hex(next_byte) # all two-byte opcodes also have their first byte in there somewhere if (current_byte in opt_table.keys()) or ((current_byte + (next_byte << 8)) in opt_table.keys()): print "debug2" # this might be a two-byte opcode possible_opcode = current_byte + (next_byte << 8) # check if this is a two-byte opcode if possible_opcode in opt_table.keys(): op_code = possible_opcode else: op_code = current_byte op = opt_table[op_code] opstr = op[0].lower() optype = op[1] print "opstr: " + opstr asm_command["type"] = "op" asm_command["id"] = op_code asm_command["format"] = opstr asm_command["opnumberthing"] = optype if "x" in opstr: print "debug3" for x in range(0, opstr.count("x")): insertion = ord(rom[offset + 1]) # Certain opcodes will have a local relative jump label # here instead of a raw hex value, but this is # controlled through asm output. insertion = "$" + hex(insertion)[2:] opstr = opstr[:opstr.find("x")].lower() + insertion + opstr[opstr.find("x")+1:].lower() current_byte_number += 1 offset += 1 if "?" in opstr: print "debug4" for y in range(0, opstr.count("?")): byte1 = ord(rom[offset + 1]) byte2 = ord(rom[offset + 2]) number = byte1 number += byte2 << 8; # In most cases, you can use a label here. Labels will # be shown during asm output. insertion = "$%.4x" % (number) opstr = opstr[:opstr.find("?")].lower() + insertion + opstr[opstr.find("?")+1:].lower() current_byte_number += 2 offset += 2 # Check for relative jumps, construct the formatted asm line. # Also set the usage of labels. if current_byte in [0x18, 0x20] + relative_jumps: # jr or jr nz print "debug5" # generate a label for the byte we're jumping to target_address = offset + 2 + c_int8(ord(rom[offset + 1])).value if target_address in asm_commands.keys(): print "debug6" asm_commands[target_address]["references"] += 1 remote_label = "asm_" + hex(target_address) asm_commands[target_address]["current_label"] = remote_label asm_command["remote_label"] = remote_label asm_command["use_remote_label"] = True else: print "debug7" remote_label = "asm_" + hex(target_address) # This remote address might not be part of this # function. asm_commands[target_address] = { "references": 1, "current_label": remote_label, } # Also, target_address can be negative (before the # start_address that the user originally requested), # and it shouldn't be shown on asm output because the # intermediate bytes (between a negative target_address # and start_address) won't be disassembled. # Don't know yet if this remote address is part of this # function or not. When the remote address is not part # of this function, the label name should not be used, # because that label will not be disassembled in the # output, until the user asks it to. asm_command["use_remote_label"] = "unknown" asm_command["remote_label"] = remote_label elif current_byte == 0x3e: last_a_address = ord(rom[offset + 1]) # store the formatted string for the output later asm_command["formatted"] = opstr if current_byte == 0x21: last_hl_address = byte1 + (byte2 << 8) # this is leftover from pokered, might be meaningless if current_byte == 0xcd: if number == 0x3d97: used_3d97 = True if current_byte == 0xc3 or current_byte in relative_unconditional_jumps: print "debug8" if current_byte == 0xc3: if number == 0x3d97: used_3d97 = True if not has_outstanding_labels(byte_labels) or all_outstanding_labels_are_reverse(byte_labels, offset): keep_reading = False break # stop reading at a jump, relative jump or return if current_byte in end_08_scripts_with: print "debug9" is_data = False if not has_outstanding_labels(byte_labels) and all_outstanding_labels_are_reverse(byte_labels, offset): keep_reading = False break else: keep_reading = True else: keep_reading = True else: # This shouldn't really happen, and means that this area of the # ROM probably doesn't represent instructions. asm_command["type"] = "data" # db asm_command["value"] = current_byte keep_reading = False # jump forward by a byte offset += 1 # save this new command in the list asm_commands[asm_command["address"]] = asm_command self.asm_commands = asm_commands print "debug10" def __str__(self): """ ASM pretty printer. """ raise NotImplementedError, "zzzzzz" class AsmList(list): """ Simple wrapper to prevent all asm lines from being shown on screen. """ def length(self): """ len(self) """ return len(self) def __repr__(self): """ Simplifies this object so that the output doesn't overflow stdout. """ return "AsmList(too long)"