Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 1 | import select |
| 2 | import socket |
| 3 | import struct |
| 4 | import sys |
| 5 | import types |
| 6 | |
| 7 | VERBOSE = None |
| 8 | |
| 9 | class SocketProtocol: |
| 10 | """A simple protocol for sending strings across a socket""" |
| 11 | BUF_SIZE = 8192 |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 12 | |
Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 13 | def __init__(self, sock): |
| 14 | self.sock = sock |
| 15 | self._buffer = '' |
| 16 | self._closed = 0 |
| 17 | |
| 18 | def close(self): |
| 19 | self._closed = 1 |
| 20 | self.sock.close() |
| 21 | |
| 22 | def send(self, buf): |
| 23 | """Encode buf and write it on the socket""" |
| 24 | if VERBOSE: |
| 25 | VERBOSE.write('send %d:%s\n' % (len(buf), `buf`)) |
| 26 | self.sock.send('%d:%s' % (len(buf), buf)) |
| 27 | |
| 28 | def receive(self, timeout=0): |
| 29 | """Get next complete string from socket or return None |
| 30 | |
| 31 | Raise EOFError on EOF |
| 32 | """ |
| 33 | buf = self._read_from_buffer() |
| 34 | if buf is not None: |
| 35 | return buf |
| 36 | recvbuf = self._read_from_socket(timeout) |
| 37 | if recvbuf is None: |
| 38 | return None |
| 39 | if recvbuf == '' and self._buffer == '': |
| 40 | raise EOFError |
| 41 | if VERBOSE: |
| 42 | VERBOSE.write('recv %s\n' % `recvbuf`) |
| 43 | self._buffer = self._buffer + recvbuf |
| 44 | r = self._read_from_buffer() |
| 45 | return r |
| 46 | |
| 47 | def _read_from_socket(self, timeout): |
| 48 | """Does not block""" |
| 49 | if self._closed: |
| 50 | return '' |
| 51 | if timeout is not None: |
| 52 | r, w, x = select.select([self.sock], [], [], timeout) |
| 53 | if timeout is None or r: |
| 54 | return self.sock.recv(self.BUF_SIZE) |
| 55 | else: |
| 56 | return None |
| 57 | |
| 58 | def _read_from_buffer(self): |
| 59 | buf = self._buffer |
| 60 | i = buf.find(':') |
| 61 | if i == -1: |
| 62 | return None |
| 63 | buflen = int(buf[:i]) |
| 64 | enclen = i + 1 + buflen |
| 65 | if len(buf) >= enclen: |
| 66 | s = buf[i+1:enclen] |
| 67 | self._buffer = buf[enclen:] |
| 68 | return s |
| 69 | else: |
| 70 | self._buffer = buf |
| 71 | return None |
| 72 | |
| 73 | # helpers for registerHandler method below |
| 74 | |
| 75 | def get_methods(obj): |
| 76 | methods = [] |
| 77 | for name in dir(obj): |
| 78 | attr = getattr(obj, name) |
| 79 | if callable(attr): |
| 80 | methods.append(name) |
| 81 | if type(obj) == types.InstanceType: |
| 82 | methods = methods + get_methods(obj.__class__) |
| 83 | if type(obj) == types.ClassType: |
| 84 | for super in obj.__bases__: |
| 85 | methods = methods + get_methods(super) |
| 86 | return methods |
| 87 | |
| 88 | class CommandProtocol: |
| 89 | def __init__(self, sockp): |
| 90 | self.sockp = sockp |
| 91 | self.seqno = 0 |
| 92 | self.handlers = {} |
| 93 | |
| 94 | def close(self): |
| 95 | self.sockp.close() |
| 96 | self.handlers.clear() |
| 97 | |
| 98 | def registerHandler(self, handler): |
| 99 | """A Handler is an object with handle_XXX methods""" |
| 100 | for methname in get_methods(handler): |
| 101 | if methname[:7] == "handle_": |
| 102 | name = methname[7:] |
| 103 | self.handlers[name] = getattr(handler, methname) |
| 104 | |
| 105 | def send(self, cmd, arg='', seqno=None): |
| 106 | if arg: |
| 107 | msg = "%s %s" % (cmd, arg) |
| 108 | else: |
| 109 | msg = cmd |
| 110 | if seqno is None: |
| 111 | seqno = self.get_seqno() |
| 112 | msgbuf = self.encode_seqno(seqno) + msg |
| 113 | self.sockp.send(msgbuf) |
| 114 | if cmd == "reply": |
| 115 | return |
| 116 | reply = self.sockp.receive(timeout=None) |
| 117 | r_cmd, r_arg, r_seqno = self._decode_msg(reply) |
| 118 | assert r_seqno == seqno and r_cmd == "reply", "bad reply" |
| 119 | return r_arg |
| 120 | |
| 121 | def _decode_msg(self, msg): |
| 122 | seqno = self.decode_seqno(msg[:self.SEQNO_ENC_LEN]) |
| 123 | msg = msg[self.SEQNO_ENC_LEN:] |
| 124 | parts = msg.split(" ", 2) |
| 125 | if len(parts) == 1: |
| 126 | cmd = msg |
| 127 | arg = '' |
| 128 | else: |
| 129 | cmd = parts[0] |
| 130 | arg = parts[1] |
| 131 | return cmd, arg, seqno |
| 132 | |
| 133 | def dispatch(self): |
| 134 | msg = self.sockp.receive() |
| 135 | if msg is None: |
| 136 | return |
| 137 | cmd, arg, seqno = self._decode_msg(msg) |
| 138 | self._current_reply = seqno |
| 139 | h = self.handlers.get(cmd, self.default_handler) |
| 140 | try: |
| 141 | r = h(arg) |
| 142 | except TypeError, msg: |
| 143 | raise TypeError, "handle_%s: %s" % (cmd, msg) |
| 144 | if self._current_reply is None: |
| 145 | if r is not None: |
| 146 | sys.stderr.write("ignoring %s return value type %s\n" % \ |
| 147 | (cmd, type(r).__name__)) |
| 148 | return |
| 149 | if r is None: |
| 150 | r = '' |
| 151 | if type(r) != types.StringType: |
| 152 | raise ValueError, "invalid return type for %s" % cmd |
| 153 | self.send("reply", r, seqno=seqno) |
| 154 | |
| 155 | def reply(self, arg=''): |
| 156 | """Send a reply immediately |
| 157 | |
| 158 | otherwise reply will be sent when handler returns |
| 159 | """ |
| 160 | self.send("reply", arg, self._current_reply) |
| 161 | self._current_reply = None |
| 162 | |
| 163 | def default_handler(self, arg): |
| 164 | sys.stderr.write("WARNING: unhandled message %s\n" % arg) |
| 165 | return '' |
| 166 | |
| 167 | SEQNO_ENC_LEN = 4 |
| 168 | |
| 169 | def get_seqno(self): |
| 170 | seqno = self.seqno |
| 171 | self.seqno = seqno + 1 |
| 172 | return seqno |
| 173 | |
| 174 | def encode_seqno(self, seqno): |
| 175 | return struct.pack("I", seqno) |
| 176 | |
| 177 | def decode_seqno(self, buf): |
| 178 | return struct.unpack("I", buf)[0] |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 179 | |
Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 180 | |
| 181 | class StdioRedirector: |
| 182 | """Redirect sys.std{in,out,err} to a set of file-like objects""" |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 183 | |
Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 184 | def __init__(self, stdin, stdout, stderr): |
| 185 | self.stdin = stdin |
| 186 | self.stdout = stdout |
| 187 | self.stderr = stderr |
| 188 | |
| 189 | def redirect(self): |
| 190 | self.save() |
| 191 | sys.stdin = self.stdin |
| 192 | sys.stdout = self.stdout |
| 193 | sys.stderr = self.stderr |
| 194 | |
| 195 | def save(self): |
| 196 | self._stdin = sys.stdin |
| 197 | self._stdout = sys.stdout |
| 198 | self._stderr = sys.stderr |
| 199 | |
| 200 | def restore(self): |
| 201 | sys.stdin = self._stdin |
| 202 | sys.stdout = self._stdout |
| 203 | sys.stderr = self._stderr |
| 204 | |
| 205 | class IOWrapper: |
| 206 | """Send output from a file-like object across a SocketProtocol |
| 207 | |
| 208 | XXX Should this be more tightly integrated with the CommandProtocol? |
| 209 | """ |
| 210 | |
| 211 | def __init__(self, name, cmdp): |
| 212 | self.name = name |
| 213 | self.cmdp = cmdp |
| 214 | self.buffer = [] |
| 215 | |
| 216 | class InputWrapper(IOWrapper): |
| 217 | def write(self, buf): |
| 218 | # XXX what should this do on Windows? |
| 219 | raise IOError, (9, '[Errno 9] Bad file descriptor') |
| 220 | |
| 221 | def read(self, arg=None): |
| 222 | if arg is not None: |
| 223 | if arg <= 0: |
| 224 | return '' |
| 225 | else: |
| 226 | arg = 0 |
| 227 | return self.cmdp.send(self.name, "read,%s" % arg) |
| 228 | |
| 229 | def readline(self): |
| 230 | return self.cmdp.send(self.name, "readline") |
| 231 | |
| 232 | class OutputWrapper(IOWrapper): |
| 233 | def write(self, buf): |
| 234 | self.cmdp.send(self.name, buf) |
| 235 | |
| 236 | def read(self, arg=None): |
| 237 | return '' |
| 238 | |
| 239 | class RemoteInterp: |
| 240 | def __init__(self, sock): |
| 241 | self._sock = SocketProtocol(sock) |
| 242 | self._cmd = CommandProtocol(self._sock) |
| 243 | self._cmd.registerHandler(self) |
| 244 | |
| 245 | def run(self): |
| 246 | try: |
| 247 | while 1: |
| 248 | self._cmd.dispatch() |
| 249 | except EOFError: |
| 250 | pass |
| 251 | |
| 252 | def handle_execfile(self, arg): |
| 253 | self._cmd.reply() |
| 254 | io = StdioRedirector(InputWrapper("stdin", self._cmd), |
| 255 | OutputWrapper("stdout", self._cmd), |
| 256 | OutputWrapper("stderr", self._cmd)) |
| 257 | io.redirect() |
| 258 | execfile(arg, {'__name__':'__main__'}) |
| 259 | io.restore() |
| 260 | self._cmd.send("terminated") |
| 261 | |
| 262 | def handle_quit(self, arg): |
| 263 | self._cmd.reply() |
| 264 | self._cmd.close() |
| 265 | |
| 266 | def startRemoteInterp(id): |
| 267 | import os |
| 268 | # UNIX domain sockets are simpler for starters |
| 269 | sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) |
| 270 | sock.bind("/var/tmp/ri.%s" % id) |
| 271 | try: |
| 272 | sock.listen(1) |
| 273 | cli, addr = sock.accept() |
| 274 | rinterp = RemoteInterp(cli) |
| 275 | rinterp.run() |
| 276 | finally: |
| 277 | os.unlink("/var/tmp/ri.%s" % id) |
| 278 | |
| 279 | class RIClient: |
| 280 | """Client of the remote interpreter""" |
| 281 | def __init__(self, sock): |
| 282 | self._sock = SocketProtocol(sock) |
| 283 | self._cmd = CommandProtocol(self._sock) |
| 284 | self._cmd.registerHandler(self) |
| 285 | |
| 286 | def execfile(self, file): |
| 287 | self._cmd.send("execfile", file) |
| 288 | |
| 289 | def run(self): |
| 290 | try: |
| 291 | while 1: |
| 292 | self._cmd.dispatch() |
| 293 | except EOFError: |
| 294 | pass |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 295 | |
Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 296 | def handle_stdout(self, buf): |
| 297 | sys.stdout.write(buf) |
| 298 | ## sys.stdout.flush() |
| 299 | |
| 300 | def handle_stderr(self, buf): |
| 301 | sys.stderr.write(buf) |
| 302 | |
| 303 | def handle_stdin(self, arg): |
| 304 | if arg == "readline": |
| 305 | return sys.stdin.readline() |
| 306 | i = arg.find(",") + 1 |
| 307 | bytes = int(arg[i:]) |
| 308 | if bytes == 0: |
| 309 | return sys.stdin.read() |
| 310 | else: |
| 311 | return sys.stdin.read(bytes) |
| 312 | |
| 313 | def handle_terminated(self, arg): |
| 314 | self._cmd.reply() |
| 315 | self._cmd.send("quit") |
| 316 | self._cmd.close() |
| 317 | |
| 318 | def riExec(id, file): |
| 319 | sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) |
| 320 | sock.connect("/var/tmp/ri.%s" % id) |
| 321 | cli = RIClient(sock) |
| 322 | cli.execfile(file) |
| 323 | cli.run() |
| 324 | |
| 325 | if __name__ == "__main__": |
Jeremy Hylton | 329e4be | 2000-03-09 19:56:50 +0000 | [diff] [blame] | 326 | import getopt |
| 327 | |
| 328 | SERVER = 1 |
| 329 | opts, args = getopt.getopt(sys.argv[1:], 'cv') |
| 330 | for o, v in opts: |
| 331 | if o == '-c': |
| 332 | SERVER = 0 |
| 333 | elif o == '-v': |
| 334 | VERBOSE = sys.stderr |
| 335 | id = args[0] |
| 336 | |
| 337 | if SERVER: |
| 338 | startRemoteInterp(id) |
| 339 | else: |
| 340 | file = args[1] |
Tim Peters | 70c4378 | 2001-01-17 08:48:39 +0000 | [diff] [blame] | 341 | riExec(id, file) |