diff --git a/cpu6502.py b/cpu6502.py index 89e41fc..74d1929 100644 --- a/cpu6502.py +++ b/cpu6502.py @@ -3,6 +3,9 @@ # originally written 2001, updated 2011 +import BaseHTTPServer +import json +import re import select import socket import struct @@ -117,7 +120,7 @@ class Disassemble: self.setup_ops() def setup_ops(self): - self.ops = [None] * 0x100 + self.ops = [(1, "???")] * 0x100 self.ops[0x00] = (1, "BRK", ) self.ops[0x01] = (2, "ORA", self.indirect_x_mode) self.ops[0x05] = (2, "ORA", self.zero_page_mode) @@ -272,143 +275,205 @@ class Disassemble: def absolute_mode(self, pc): a = self.cpu.read_word(pc + 1) - return "$%04X [%04X] = %02X" % (a, a, self.cpu.read_word(a)) + return { + "operand": "$%04X" % a, + "memory": [a, 2, self.cpu.read_word(a)], + } def absolute_x_mode(self, pc): a = self.cpu.read_word(pc + 1) e = a + self.cpu.x_index - return "$%04X,X [%04X] = %02X" % (a, e, self.cpu.read_byte(e)) + return { + "operand": "$%04X,X" % a, + "memory": [e, 1, self.cpu.read_byte(e)], + } def absolute_y_mode(self, pc): a = self.cpu.read_word(pc + 1) e = a + self.cpu.y_index - return "$%04X,Y [%04X] = %02X" % (a, e, self.cpu.read_byte(e)) + return { + "operand": "$%04X,Y" % a, + "memory": [e, 1, self.cpu.read_byte(e)], + } def immediate_mode(self, pc): - return "#$%02X" % (self.cpu.read_byte(pc + 1)) + return { + "operand": "#$%02X" % (self.cpu.read_byte(pc + 1)), + } def indirect_mode(self, pc): a = self.cpu.read_word(pc + 1) - return "($%04X) [%04X] = %02X" % (a, a, self.cpu.read_word(a)) + return { + "operand": "($%04X)" % a, + "memory": [a, 2, self.cpu.read_word(a)], + } def indirect_x_mode(self, pc): z = self.cpu.read_byte(pc + 1) a = self.cpu.read_word((z + self.cpu.x_index) % 0x100) - return "($%02X,X) [%04X] = %02X" % (z, a, self.cpu.read_byte(a)) + return { + "operand": "($%02X,X)" % z, + "memory": [a, 1, self.cpu.read_byte(a)], + } def indirect_y_mode(self, pc): z = self.cpu.read_byte(pc + 1) a = self.cpu.read_word(z) + self.cpu.y_index - return "($%02X),Y [%04X] = %02X" % (z, a, self.cpu.read_byte(a)) + return { + "operand": "($%02X),Y" % z, + "memory": [a, 1, self.cpu.read_byte(a)], + } def relative_mode(self, pc): - return "$%04X" % (pc + signed(self.cpu.read_byte(pc + 1) + 2)) + return { + "operand": "$%04X" % (pc + signed(self.cpu.read_byte(pc + 1) + 2)), + } def zero_page_mode(self, pc): a = self.cpu.read_byte(pc + 1) - return "$%02X [%04X] = %02X" % (a, a, self.cpu.read_byte(a)) + return { + "operand": "$%02X" % a, + "memory": [a, 1, self.cpu.read_byte(a)], + } def zero_page_x_mode(self, pc): z = self.cpu.read_byte(pc + 1) a = (z + self.cpu.x_index) % 0x100 - return "$%02X,X [%04X] = %02X" % (z, a, self.cpu.read_byte(a)) + return { + "operand": "$%02X,X" % z, + "memory": [a, 1, self.cpu.read_byte(a)], + } def zero_page_y_mode(self, pc): z = self.cpu.read_byte(pc + 1) a = (z + self.cpu.y_index) % 0x100 - return "$%02X,Y [%04X] = %02X" % (z, a, self.cpu.read_byte(a)) + return { + "operand": "$%02X,Y" % z, + "memory": [a, 1, self.cpu.read_byte(a)], + } def disasm(self, pc): op = self.cpu.read_byte(pc) info = self.ops[op] - s = "%04X " % (pc) - for i in range(3): - if i < info[0]: - s += "%02X " % self.cpu.read_byte(pc + i) - else: - s += " " - s += " %s" % (info[1]) + r = { + "address": pc, + "bytes": [self.cpu.read_byte(pc + i) for i in range(info[0])], + "mnemonic": info[1], + } if len(info) > 2: - s += " " + info[2](pc) - return s + r.update(info[2](pc)) + return r, info[0] -class ControlHandler: +class ControlHandler(BaseHTTPServer.BaseHTTPRequestHandler): - def __init__(self, cpu, sock): + def __init__(self, request, client_address, server, cpu): self.cpu = cpu - self.sock = sock - self.sock.send("ApplePy 6502 core\n") - self.buffer = "" self.disassemble = Disassemble(self.cpu, self.cpu.memory) - def cmd_disassemble(self, args): - addr = int(args[1]) - self.sock.send(self.disassemble.disasm(addr) + "\n") + self.get_urls = { + r"/disassemble/(\d+)$": self.get_disassemble, + r"/memory/(\d+)(-(\d+))?$": self.get_memory, + r"/memory/(\d+)(-(\d+))?/raw$": self.get_memory_raw, + r"/status$": self.get_status, + } - def cmd_dump(self, args): - addr = int(args[1]) - length = int(args[2]) - self.sock.send(" ".join("%02X" % self.cpu.read_byte(x) for x in range(addr, addr + length)) + "\n") + self.post_urls = { + #r"/memory/(\d+)(-(\d+))?$": self.post_memory, + #r"/memory/(\d+)(-(\d+))?/raw$": self.post_memory_raw, + r"/quit$": self.post_quit, + r"/reset$": self.post_reset, + } - def cmd_help(self, args): - self.sock.send("commands: %s\n" % ", ".join(sorted(x[4:] for x in dir(self) if x.startswith("cmd_")))) + BaseHTTPServer.BaseHTTPRequestHandler.__init__(self, request, client_address, server) - def cmd_peek(self, args): - addr = int(args[1]) - self.sock.send("%02X\n" % self.cpu.read_byte(addr)) + def log_request(self, code, size=0): + pass - def cmd_poke(self, args): - addr = int(args[1]) - val = int(args[2]) - self.cpu.write_byte(addr, val) - self.sock.send("poked\n") + def dispatch(self, urls): + for r, f in urls.items(): + m = re.match(r, self.path) + if m is not None: + f(m) + break + else: + self.send_response(404) + self.end_headers() - def cmd_status(self, args): - self.sock.send("A=%02X X=%02X Y=%02X S=%02X PC=%04X F=%c%c0%c%c%c%c%c\n" % ( - self.cpu.accumulator, - self.cpu.x_index, - self.cpu.y_index, - self.cpu.stack_pointer, - self.cpu.program_counter, - "N" if self.cpu.sign_flag else "n", - "V" if self.cpu.overflow_flag else "v", - "B" if self.cpu.break_flag else "b", - "D" if self.cpu.decimal_mode_flag else "d", - "I" if self.cpu.interrupt_disable_flag else "i", - "Z" if self.cpu.zero_flag else "z", - "C" if self.cpu.carry_flag else "c", - )) + def response(self, s): + self.send_response(200) + self.send_header("Content-Length", str(len(s))) + self.end_headers() + self.wfile.write(s) - def cmd_quit(self, args): + def do_GET(self): + self.dispatch(self.get_urls) + + def do_POST(self): + self.dispatch(self.post_urls) + + def get_disassemble(self, m): + addr = int(m.group(1)) + r = [] + n = 20 + while n > 0: + dis, length = self.disassemble.disasm(addr) + r.append(dis) + addr += length + n -= 1 + self.response(json.dumps(r)) + + def get_memory_raw(self, m): + addr = int(m.group(1)) + e = m.group(3) + if e is not None: + end = int(e) + else: + end = addr + self.response("".join([chr(self.cpu.read_byte(x)) for x in range(addr, end + 1)])) + + def get_memory(self, m): + addr = int(m.group(1)) + e = m.group(3) + if e is not None: + end = int(e) + else: + end = addr + self.response(json.dumps(list(map(self.cpu.read_byte, range(addr, end + 1))))) + + def get_status(self, m): + self.response(json.dumps(dict((x, getattr(self.cpu, x)) for x in ( + "accumulator", + "x_index", + "y_index", + "stack_pointer", + "program_counter", + "sign_flag", + "overflow_flag", + "break_flag", + "decimal_mode_flag", + "interrupt_disable_flag", + "zero_flag", + "carry_flag", + )))) + + def post_quit(self, m): self.cpu.quit = True - self.sock.send("quitting\n") + self.response("") - def cmd_reset(self, args): + def post_reset(self, m): self.cpu.reset() self.cpu.running = True - self.sock.send("resetting\n") + self.response("") - def fileno(self): - return self.sock.fileno() - def handle_read(self): - buf = self.sock.recv(1024) - if not buf: - self.cpu.control.remove(self) - return - self.buffer += buf - while True: - i = self.buffer.find("\n") - if i < 0: - break - s = self.buffer[:i].strip() - self.buffer = self.buffer[i+1:] - a = s.split() - try: - getattr(self, "cmd_" + a[0])(a) - except AttributeError: - self.sock.send("unknown command\n") +class ControlHandlerFactory: + + def __init__(self, cpu): + self.cpu = cpu + + def __call__(self, request, client_address, server): + return ControlHandler(request, client_address, server, self.cpu) class CPU: @@ -419,11 +484,7 @@ class CPU: def __init__(self, memory): self.memory = memory - self.control_listener = socket.socket() - self.control_listener.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, True) - self.control_listener.bind(("127.0.0.1", 6502)) - self.control_listener.listen(1) - self.control = [] + self.control_server = BaseHTTPServer.HTTPServer(("127.0.0.1", 6502), ControlHandlerFactory(self)) self.accumulator = 0x00 self.x_index = 0x00 @@ -613,14 +674,17 @@ class CPU: timeout = 0 if not self.running: timeout = 1 - sockets = [self.control_listener] + self.control + # Currently this handler blocks from the moment + # a connection is accepted until the response + # is sent. TODO: use an async HTTP server that + # handles input data asynchronously. + sockets = [self.control_server] rs, _, _ = select.select(sockets, [], [], timeout) for s in rs: - if s is self.control_listener: - cs, _ = self.control_listener.accept() - self.control.append(ControlHandler(self, cs)) + if s is self.control_server: + self.control_server._handle_request_noblock() else: - s.handle_read() + pass count = 1000 while count > 0 and self.running: