Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame^] | 1 | """Event loop using a selector and related classes. |
| 2 | |
| 3 | A selector is a "notify-when-ready" multiplexer. For a subclass which |
| 4 | also includes support for signal handling, see the unix_events sub-module. |
| 5 | """ |
| 6 | |
| 7 | import collections |
| 8 | import socket |
| 9 | try: |
| 10 | import ssl |
| 11 | except ImportError: # pragma: no cover |
| 12 | ssl = None |
| 13 | |
| 14 | from . import base_events |
| 15 | from . import constants |
| 16 | from . import events |
| 17 | from . import futures |
| 18 | from . import selectors |
| 19 | from . import transports |
| 20 | from .log import asyncio_log |
| 21 | |
| 22 | |
| 23 | class BaseSelectorEventLoop(base_events.BaseEventLoop): |
| 24 | """Selector event loop. |
| 25 | |
| 26 | See events.EventLoop for API specification. |
| 27 | """ |
| 28 | |
| 29 | def __init__(self, selector=None): |
| 30 | super().__init__() |
| 31 | |
| 32 | if selector is None: |
| 33 | selector = selectors.DefaultSelector() |
| 34 | asyncio_log.debug('Using selector: %s', selector.__class__.__name__) |
| 35 | self._selector = selector |
| 36 | self._make_self_pipe() |
| 37 | |
| 38 | def _make_socket_transport(self, sock, protocol, waiter=None, *, |
| 39 | extra=None, server=None): |
| 40 | return _SelectorSocketTransport(self, sock, protocol, waiter, |
| 41 | extra, server) |
| 42 | |
| 43 | def _make_ssl_transport(self, rawsock, protocol, sslcontext, waiter, *, |
| 44 | server_side=False, server_hostname=None, |
| 45 | extra=None, server=None): |
| 46 | return _SelectorSslTransport( |
| 47 | self, rawsock, protocol, sslcontext, waiter, |
| 48 | server_side, server_hostname, extra, server) |
| 49 | |
| 50 | def _make_datagram_transport(self, sock, protocol, |
| 51 | address=None, extra=None): |
| 52 | return _SelectorDatagramTransport(self, sock, protocol, address, extra) |
| 53 | |
| 54 | def close(self): |
| 55 | if self._selector is not None: |
| 56 | self._close_self_pipe() |
| 57 | self._selector.close() |
| 58 | self._selector = None |
| 59 | |
| 60 | def _socketpair(self): |
| 61 | raise NotImplementedError |
| 62 | |
| 63 | def _close_self_pipe(self): |
| 64 | self.remove_reader(self._ssock.fileno()) |
| 65 | self._ssock.close() |
| 66 | self._ssock = None |
| 67 | self._csock.close() |
| 68 | self._csock = None |
| 69 | self._internal_fds -= 1 |
| 70 | |
| 71 | def _make_self_pipe(self): |
| 72 | # A self-socket, really. :-) |
| 73 | self._ssock, self._csock = self._socketpair() |
| 74 | self._ssock.setblocking(False) |
| 75 | self._csock.setblocking(False) |
| 76 | self._internal_fds += 1 |
| 77 | self.add_reader(self._ssock.fileno(), self._read_from_self) |
| 78 | |
| 79 | def _read_from_self(self): |
| 80 | try: |
| 81 | self._ssock.recv(1) |
| 82 | except (BlockingIOError, InterruptedError): |
| 83 | pass |
| 84 | |
| 85 | def _write_to_self(self): |
| 86 | try: |
| 87 | self._csock.send(b'x') |
| 88 | except (BlockingIOError, InterruptedError): |
| 89 | pass |
| 90 | |
| 91 | def _start_serving(self, protocol_factory, sock, ssl=None, server=None): |
| 92 | self.add_reader(sock.fileno(), self._accept_connection, |
| 93 | protocol_factory, sock, ssl, server) |
| 94 | |
| 95 | def _accept_connection(self, protocol_factory, sock, ssl=None, |
| 96 | server=None): |
| 97 | try: |
| 98 | conn, addr = sock.accept() |
| 99 | conn.setblocking(False) |
| 100 | except (BlockingIOError, InterruptedError): |
| 101 | pass # False alarm. |
| 102 | except Exception: |
| 103 | # Bad error. Stop serving. |
| 104 | self.remove_reader(sock.fileno()) |
| 105 | sock.close() |
| 106 | # There's nowhere to send the error, so just log it. |
| 107 | # TODO: Someone will want an error handler for this. |
| 108 | asyncio_log.exception('Accept failed') |
| 109 | else: |
| 110 | if ssl: |
| 111 | self._make_ssl_transport( |
| 112 | conn, protocol_factory(), ssl, None, |
| 113 | server_side=True, extra={'peername': addr}, server=server) |
| 114 | else: |
| 115 | self._make_socket_transport( |
| 116 | conn, protocol_factory(), extra={'peername': addr}, |
| 117 | server=server) |
| 118 | # It's now up to the protocol to handle the connection. |
| 119 | |
| 120 | def add_reader(self, fd, callback, *args): |
| 121 | """Add a reader callback.""" |
| 122 | handle = events.make_handle(callback, args) |
| 123 | try: |
| 124 | key = self._selector.get_key(fd) |
| 125 | except KeyError: |
| 126 | self._selector.register(fd, selectors.EVENT_READ, |
| 127 | (handle, None)) |
| 128 | else: |
| 129 | mask, (reader, writer) = key.events, key.data |
| 130 | self._selector.modify(fd, mask | selectors.EVENT_READ, |
| 131 | (handle, writer)) |
| 132 | if reader is not None: |
| 133 | reader.cancel() |
| 134 | |
| 135 | def remove_reader(self, fd): |
| 136 | """Remove a reader callback.""" |
| 137 | try: |
| 138 | key = self._selector.get_key(fd) |
| 139 | except KeyError: |
| 140 | return False |
| 141 | else: |
| 142 | mask, (reader, writer) = key.events, key.data |
| 143 | mask &= ~selectors.EVENT_READ |
| 144 | if not mask: |
| 145 | self._selector.unregister(fd) |
| 146 | else: |
| 147 | self._selector.modify(fd, mask, (None, writer)) |
| 148 | |
| 149 | if reader is not None: |
| 150 | reader.cancel() |
| 151 | return True |
| 152 | else: |
| 153 | return False |
| 154 | |
| 155 | def add_writer(self, fd, callback, *args): |
| 156 | """Add a writer callback..""" |
| 157 | handle = events.make_handle(callback, args) |
| 158 | try: |
| 159 | key = self._selector.get_key(fd) |
| 160 | except KeyError: |
| 161 | self._selector.register(fd, selectors.EVENT_WRITE, |
| 162 | (None, handle)) |
| 163 | else: |
| 164 | mask, (reader, writer) = key.events, key.data |
| 165 | self._selector.modify(fd, mask | selectors.EVENT_WRITE, |
| 166 | (reader, handle)) |
| 167 | if writer is not None: |
| 168 | writer.cancel() |
| 169 | |
| 170 | def remove_writer(self, fd): |
| 171 | """Remove a writer callback.""" |
| 172 | try: |
| 173 | key = self._selector.get_key(fd) |
| 174 | except KeyError: |
| 175 | return False |
| 176 | else: |
| 177 | mask, (reader, writer) = key.events, key.data |
| 178 | # Remove both writer and connector. |
| 179 | mask &= ~selectors.EVENT_WRITE |
| 180 | if not mask: |
| 181 | self._selector.unregister(fd) |
| 182 | else: |
| 183 | self._selector.modify(fd, mask, (reader, None)) |
| 184 | |
| 185 | if writer is not None: |
| 186 | writer.cancel() |
| 187 | return True |
| 188 | else: |
| 189 | return False |
| 190 | |
| 191 | def sock_recv(self, sock, n): |
| 192 | """XXX""" |
| 193 | fut = futures.Future(loop=self) |
| 194 | self._sock_recv(fut, False, sock, n) |
| 195 | return fut |
| 196 | |
| 197 | def _sock_recv(self, fut, registered, sock, n): |
| 198 | fd = sock.fileno() |
| 199 | if registered: |
| 200 | # Remove the callback early. It should be rare that the |
| 201 | # selector says the fd is ready but the call still returns |
| 202 | # EAGAIN, and I am willing to take a hit in that case in |
| 203 | # order to simplify the common case. |
| 204 | self.remove_reader(fd) |
| 205 | if fut.cancelled(): |
| 206 | return |
| 207 | try: |
| 208 | data = sock.recv(n) |
| 209 | except (BlockingIOError, InterruptedError): |
| 210 | self.add_reader(fd, self._sock_recv, fut, True, sock, n) |
| 211 | except Exception as exc: |
| 212 | fut.set_exception(exc) |
| 213 | else: |
| 214 | fut.set_result(data) |
| 215 | |
| 216 | def sock_sendall(self, sock, data): |
| 217 | """XXX""" |
| 218 | fut = futures.Future(loop=self) |
| 219 | if data: |
| 220 | self._sock_sendall(fut, False, sock, data) |
| 221 | else: |
| 222 | fut.set_result(None) |
| 223 | return fut |
| 224 | |
| 225 | def _sock_sendall(self, fut, registered, sock, data): |
| 226 | fd = sock.fileno() |
| 227 | |
| 228 | if registered: |
| 229 | self.remove_writer(fd) |
| 230 | if fut.cancelled(): |
| 231 | return |
| 232 | |
| 233 | try: |
| 234 | n = sock.send(data) |
| 235 | except (BlockingIOError, InterruptedError): |
| 236 | n = 0 |
| 237 | except Exception as exc: |
| 238 | fut.set_exception(exc) |
| 239 | return |
| 240 | |
| 241 | if n == len(data): |
| 242 | fut.set_result(None) |
| 243 | else: |
| 244 | if n: |
| 245 | data = data[n:] |
| 246 | self.add_writer(fd, self._sock_sendall, fut, True, sock, data) |
| 247 | |
| 248 | def sock_connect(self, sock, address): |
| 249 | """XXX""" |
| 250 | # That address better not require a lookup! We're not calling |
| 251 | # self.getaddrinfo() for you here. But verifying this is |
| 252 | # complicated; the socket module doesn't have a pattern for |
| 253 | # IPv6 addresses (there are too many forms, apparently). |
| 254 | fut = futures.Future(loop=self) |
| 255 | self._sock_connect(fut, False, sock, address) |
| 256 | return fut |
| 257 | |
| 258 | def _sock_connect(self, fut, registered, sock, address): |
| 259 | # TODO: Use getaddrinfo() to look up the address, to avoid the |
| 260 | # trap of hanging the entire event loop when the address |
| 261 | # requires doing a DNS lookup. (OTOH, the caller should |
| 262 | # already have done this, so it would be nice if we could |
| 263 | # easily tell whether the address needs looking up or not. I |
| 264 | # know how to do this for IPv4, but IPv6 addresses have many |
| 265 | # syntaxes.) |
| 266 | fd = sock.fileno() |
| 267 | if registered: |
| 268 | self.remove_writer(fd) |
| 269 | if fut.cancelled(): |
| 270 | return |
| 271 | try: |
| 272 | if not registered: |
| 273 | # First time around. |
| 274 | sock.connect(address) |
| 275 | else: |
| 276 | err = sock.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR) |
| 277 | if err != 0: |
| 278 | # Jump to the except clause below. |
| 279 | raise OSError(err, 'Connect call failed') |
| 280 | except (BlockingIOError, InterruptedError): |
| 281 | self.add_writer(fd, self._sock_connect, fut, True, sock, address) |
| 282 | except Exception as exc: |
| 283 | fut.set_exception(exc) |
| 284 | else: |
| 285 | fut.set_result(None) |
| 286 | |
| 287 | def sock_accept(self, sock): |
| 288 | """XXX""" |
| 289 | fut = futures.Future(loop=self) |
| 290 | self._sock_accept(fut, False, sock) |
| 291 | return fut |
| 292 | |
| 293 | def _sock_accept(self, fut, registered, sock): |
| 294 | fd = sock.fileno() |
| 295 | if registered: |
| 296 | self.remove_reader(fd) |
| 297 | if fut.cancelled(): |
| 298 | return |
| 299 | try: |
| 300 | conn, address = sock.accept() |
| 301 | conn.setblocking(False) |
| 302 | except (BlockingIOError, InterruptedError): |
| 303 | self.add_reader(fd, self._sock_accept, fut, True, sock) |
| 304 | except Exception as exc: |
| 305 | fut.set_exception(exc) |
| 306 | else: |
| 307 | fut.set_result((conn, address)) |
| 308 | |
| 309 | def _process_events(self, event_list): |
| 310 | for key, mask in event_list: |
| 311 | fileobj, (reader, writer) = key.fileobj, key.data |
| 312 | if mask & selectors.EVENT_READ and reader is not None: |
| 313 | if reader._cancelled: |
| 314 | self.remove_reader(fileobj) |
| 315 | else: |
| 316 | self._add_callback(reader) |
| 317 | if mask & selectors.EVENT_WRITE and writer is not None: |
| 318 | if writer._cancelled: |
| 319 | self.remove_writer(fileobj) |
| 320 | else: |
| 321 | self._add_callback(writer) |
| 322 | |
| 323 | def _stop_serving(self, sock): |
| 324 | self.remove_reader(sock.fileno()) |
| 325 | sock.close() |
| 326 | |
| 327 | |
| 328 | class _SelectorTransport(transports.Transport): |
| 329 | |
| 330 | max_size = 256 * 1024 # Buffer size passed to recv(). |
| 331 | |
| 332 | def __init__(self, loop, sock, protocol, extra, server=None): |
| 333 | super().__init__(extra) |
| 334 | self._extra['socket'] = sock |
| 335 | self._extra['sockname'] = sock.getsockname() |
| 336 | if 'peername' not in self._extra: |
| 337 | try: |
| 338 | self._extra['peername'] = sock.getpeername() |
| 339 | except socket.error: |
| 340 | self._extra['peername'] = None |
| 341 | self._loop = loop |
| 342 | self._sock = sock |
| 343 | self._sock_fd = sock.fileno() |
| 344 | self._protocol = protocol |
| 345 | self._server = server |
| 346 | self._buffer = collections.deque() |
| 347 | self._conn_lost = 0 |
| 348 | self._closing = False # Set when close() called. |
| 349 | if server is not None: |
| 350 | server.attach(self) |
| 351 | |
| 352 | def abort(self): |
| 353 | self._force_close(None) |
| 354 | |
| 355 | def close(self): |
| 356 | if self._closing: |
| 357 | return |
| 358 | self._closing = True |
| 359 | self._conn_lost += 1 |
| 360 | self._loop.remove_reader(self._sock_fd) |
| 361 | if not self._buffer: |
| 362 | self._loop.call_soon(self._call_connection_lost, None) |
| 363 | |
| 364 | def _fatal_error(self, exc): |
| 365 | # should be called from exception handler only |
| 366 | asyncio_log.exception('Fatal error for %s', self) |
| 367 | self._force_close(exc) |
| 368 | |
| 369 | def _force_close(self, exc): |
| 370 | if self._buffer: |
| 371 | self._buffer.clear() |
| 372 | self._loop.remove_writer(self._sock_fd) |
| 373 | |
| 374 | if self._closing: |
| 375 | return |
| 376 | |
| 377 | self._closing = True |
| 378 | self._conn_lost += 1 |
| 379 | self._loop.remove_reader(self._sock_fd) |
| 380 | self._loop.call_soon(self._call_connection_lost, exc) |
| 381 | |
| 382 | def _call_connection_lost(self, exc): |
| 383 | try: |
| 384 | self._protocol.connection_lost(exc) |
| 385 | finally: |
| 386 | self._sock.close() |
| 387 | self._sock = None |
| 388 | self._protocol = None |
| 389 | self._loop = None |
| 390 | server = self._server |
| 391 | if server is not None: |
| 392 | server.detach(self) |
| 393 | self._server = None |
| 394 | |
| 395 | |
| 396 | class _SelectorSocketTransport(_SelectorTransport): |
| 397 | |
| 398 | def __init__(self, loop, sock, protocol, waiter=None, |
| 399 | extra=None, server=None): |
| 400 | super().__init__(loop, sock, protocol, extra, server) |
| 401 | self._eof = False |
| 402 | self._paused = False |
| 403 | |
| 404 | self._loop.add_reader(self._sock_fd, self._read_ready) |
| 405 | self._loop.call_soon(self._protocol.connection_made, self) |
| 406 | if waiter is not None: |
| 407 | self._loop.call_soon(waiter.set_result, None) |
| 408 | |
| 409 | def pause(self): |
| 410 | assert not self._closing, 'Cannot pause() when closing' |
| 411 | assert not self._paused, 'Already paused' |
| 412 | self._paused = True |
| 413 | self._loop.remove_reader(self._sock_fd) |
| 414 | |
| 415 | def resume(self): |
| 416 | assert self._paused, 'Not paused' |
| 417 | self._paused = False |
| 418 | if self._closing: |
| 419 | return |
| 420 | self._loop.add_reader(self._sock_fd, self._read_ready) |
| 421 | |
| 422 | def _read_ready(self): |
| 423 | try: |
| 424 | data = self._sock.recv(self.max_size) |
| 425 | except (BlockingIOError, InterruptedError): |
| 426 | pass |
| 427 | except ConnectionResetError as exc: |
| 428 | self._force_close(exc) |
| 429 | except Exception as exc: |
| 430 | self._fatal_error(exc) |
| 431 | else: |
| 432 | if data: |
| 433 | self._protocol.data_received(data) |
| 434 | else: |
| 435 | keep_open = self._protocol.eof_received() |
| 436 | if not keep_open: |
| 437 | self.close() |
| 438 | |
| 439 | def write(self, data): |
| 440 | assert isinstance(data, bytes), repr(type(data)) |
| 441 | assert not self._eof, 'Cannot call write() after write_eof()' |
| 442 | if not data: |
| 443 | return |
| 444 | |
| 445 | if self._conn_lost: |
| 446 | if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| 447 | asyncio_log.warning('socket.send() raised exception.') |
| 448 | self._conn_lost += 1 |
| 449 | return |
| 450 | |
| 451 | if not self._buffer: |
| 452 | # Attempt to send it right away first. |
| 453 | try: |
| 454 | n = self._sock.send(data) |
| 455 | except (BlockingIOError, InterruptedError): |
| 456 | n = 0 |
| 457 | except (BrokenPipeError, ConnectionResetError) as exc: |
| 458 | self._force_close(exc) |
| 459 | return |
| 460 | except OSError as exc: |
| 461 | self._fatal_error(exc) |
| 462 | return |
| 463 | else: |
| 464 | data = data[n:] |
| 465 | if not data: |
| 466 | return |
| 467 | # Start async I/O. |
| 468 | self._loop.add_writer(self._sock_fd, self._write_ready) |
| 469 | |
| 470 | self._buffer.append(data) |
| 471 | |
| 472 | def _write_ready(self): |
| 473 | data = b''.join(self._buffer) |
| 474 | assert data, 'Data should not be empty' |
| 475 | |
| 476 | self._buffer.clear() |
| 477 | try: |
| 478 | n = self._sock.send(data) |
| 479 | except (BlockingIOError, InterruptedError): |
| 480 | self._buffer.append(data) |
| 481 | except (BrokenPipeError, ConnectionResetError) as exc: |
| 482 | self._loop.remove_writer(self._sock_fd) |
| 483 | self._force_close(exc) |
| 484 | except Exception as exc: |
| 485 | self._loop.remove_writer(self._sock_fd) |
| 486 | self._fatal_error(exc) |
| 487 | else: |
| 488 | data = data[n:] |
| 489 | if not data: |
| 490 | self._loop.remove_writer(self._sock_fd) |
| 491 | if self._closing: |
| 492 | self._call_connection_lost(None) |
| 493 | elif self._eof: |
| 494 | self._sock.shutdown(socket.SHUT_WR) |
| 495 | return |
| 496 | |
| 497 | self._buffer.append(data) # Try again later. |
| 498 | |
| 499 | def write_eof(self): |
| 500 | if self._eof: |
| 501 | return |
| 502 | self._eof = True |
| 503 | if not self._buffer: |
| 504 | self._sock.shutdown(socket.SHUT_WR) |
| 505 | |
| 506 | def can_write_eof(self): |
| 507 | return True |
| 508 | |
| 509 | |
| 510 | class _SelectorSslTransport(_SelectorTransport): |
| 511 | |
| 512 | def __init__(self, loop, rawsock, protocol, sslcontext, waiter=None, |
| 513 | server_side=False, server_hostname=None, |
| 514 | extra=None, server=None): |
| 515 | if server_side: |
| 516 | assert isinstance( |
| 517 | sslcontext, ssl.SSLContext), 'Must pass an SSLContext' |
| 518 | else: |
| 519 | # Client-side may pass ssl=True to use a default context. |
| 520 | # The default is the same as used by urllib. |
| 521 | if sslcontext is None: |
| 522 | sslcontext = ssl.SSLContext(ssl.PROTOCOL_SSLv23) |
| 523 | sslcontext.options |= ssl.OP_NO_SSLv2 |
| 524 | sslcontext.set_default_verify_paths() |
| 525 | sslcontext.verify_mode = ssl.CERT_REQUIRED |
| 526 | wrap_kwargs = { |
| 527 | 'server_side': server_side, |
| 528 | 'do_handshake_on_connect': False, |
| 529 | } |
| 530 | if server_hostname is not None and not server_side and ssl.HAS_SNI: |
| 531 | wrap_kwargs['server_hostname'] = server_hostname |
| 532 | sslsock = sslcontext.wrap_socket(rawsock, **wrap_kwargs) |
| 533 | |
| 534 | super().__init__(loop, sslsock, protocol, extra, server) |
| 535 | |
| 536 | self._server_hostname = server_hostname |
| 537 | self._waiter = waiter |
| 538 | self._rawsock = rawsock |
| 539 | self._sslcontext = sslcontext |
| 540 | self._paused = False |
| 541 | |
| 542 | # SSL-specific extra info. (peercert is set later) |
| 543 | self._extra.update(sslcontext=sslcontext) |
| 544 | |
| 545 | self._on_handshake() |
| 546 | |
| 547 | def _on_handshake(self): |
| 548 | try: |
| 549 | self._sock.do_handshake() |
| 550 | except ssl.SSLWantReadError: |
| 551 | self._loop.add_reader(self._sock_fd, self._on_handshake) |
| 552 | return |
| 553 | except ssl.SSLWantWriteError: |
| 554 | self._loop.add_writer(self._sock_fd, self._on_handshake) |
| 555 | return |
| 556 | except Exception as exc: |
| 557 | self._sock.close() |
| 558 | if self._waiter is not None: |
| 559 | self._waiter.set_exception(exc) |
| 560 | return |
| 561 | except BaseException as exc: |
| 562 | self._sock.close() |
| 563 | if self._waiter is not None: |
| 564 | self._waiter.set_exception(exc) |
| 565 | raise |
| 566 | |
| 567 | # Verify hostname if requested. |
| 568 | peercert = self._sock.getpeercert() |
| 569 | if (self._server_hostname is not None and |
| 570 | self._sslcontext.verify_mode == ssl.CERT_REQUIRED): |
| 571 | try: |
| 572 | ssl.match_hostname(peercert, self._server_hostname) |
| 573 | except Exception as exc: |
| 574 | self._sock.close() |
| 575 | if self._waiter is not None: |
| 576 | self._waiter.set_exception(exc) |
| 577 | return |
| 578 | |
| 579 | # Add extra info that becomes available after handshake. |
| 580 | self._extra.update(peercert=peercert, |
| 581 | cipher=self._sock.cipher(), |
| 582 | compression=self._sock.compression(), |
| 583 | ) |
| 584 | |
| 585 | self._loop.remove_reader(self._sock_fd) |
| 586 | self._loop.remove_writer(self._sock_fd) |
| 587 | self._loop.add_reader(self._sock_fd, self._on_ready) |
| 588 | self._loop.add_writer(self._sock_fd, self._on_ready) |
| 589 | self._loop.call_soon(self._protocol.connection_made, self) |
| 590 | if self._waiter is not None: |
| 591 | self._loop.call_soon(self._waiter.set_result, None) |
| 592 | |
| 593 | def pause(self): |
| 594 | # XXX This is a bit icky, given the comment at the top of |
| 595 | # _on_ready(). Is it possible to evoke a deadlock? I don't |
| 596 | # know, although it doesn't look like it; write() will still |
| 597 | # accept more data for the buffer and eventually the app will |
| 598 | # call resume() again, and things will flow again. |
| 599 | |
| 600 | assert not self._closing, 'Cannot pause() when closing' |
| 601 | assert not self._paused, 'Already paused' |
| 602 | self._paused = True |
| 603 | self._loop.remove_reader(self._sock_fd) |
| 604 | |
| 605 | def resume(self): |
| 606 | assert self._paused, 'Not paused' |
| 607 | self._paused = False |
| 608 | if self._closing: |
| 609 | return |
| 610 | self._loop.add_reader(self._sock_fd, self._on_ready) |
| 611 | |
| 612 | def _on_ready(self): |
| 613 | # Because of renegotiations (?), there's no difference between |
| 614 | # readable and writable. We just try both. XXX This may be |
| 615 | # incorrect; we probably need to keep state about what we |
| 616 | # should do next. |
| 617 | |
| 618 | # First try reading. |
| 619 | if not self._closing and not self._paused: |
| 620 | try: |
| 621 | data = self._sock.recv(self.max_size) |
| 622 | except (BlockingIOError, InterruptedError, |
| 623 | ssl.SSLWantReadError, ssl.SSLWantWriteError): |
| 624 | pass |
| 625 | except ConnectionResetError as exc: |
| 626 | self._force_close(exc) |
| 627 | except Exception as exc: |
| 628 | self._fatal_error(exc) |
| 629 | else: |
| 630 | if data: |
| 631 | self._protocol.data_received(data) |
| 632 | else: |
| 633 | try: |
| 634 | self._protocol.eof_received() |
| 635 | finally: |
| 636 | self.close() |
| 637 | |
| 638 | # Now try writing, if there's anything to write. |
| 639 | if self._buffer: |
| 640 | data = b''.join(self._buffer) |
| 641 | self._buffer.clear() |
| 642 | try: |
| 643 | n = self._sock.send(data) |
| 644 | except (BlockingIOError, InterruptedError, |
| 645 | ssl.SSLWantReadError, ssl.SSLWantWriteError): |
| 646 | n = 0 |
| 647 | except (BrokenPipeError, ConnectionResetError) as exc: |
| 648 | self._loop.remove_writer(self._sock_fd) |
| 649 | self._force_close(exc) |
| 650 | return |
| 651 | except Exception as exc: |
| 652 | self._loop.remove_writer(self._sock_fd) |
| 653 | self._fatal_error(exc) |
| 654 | return |
| 655 | |
| 656 | if n < len(data): |
| 657 | self._buffer.append(data[n:]) |
| 658 | |
| 659 | if self._closing and not self._buffer: |
| 660 | self._loop.remove_writer(self._sock_fd) |
| 661 | self._call_connection_lost(None) |
| 662 | |
| 663 | def write(self, data): |
| 664 | assert isinstance(data, bytes), repr(type(data)) |
| 665 | if not data: |
| 666 | return |
| 667 | |
| 668 | if self._conn_lost: |
| 669 | if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| 670 | asyncio_log.warning('socket.send() raised exception.') |
| 671 | self._conn_lost += 1 |
| 672 | return |
| 673 | |
| 674 | self._buffer.append(data) |
| 675 | # We could optimize, but the callback can do this for now. |
| 676 | |
| 677 | def can_write_eof(self): |
| 678 | return False |
| 679 | |
| 680 | def close(self): |
| 681 | if self._closing: |
| 682 | return |
| 683 | self._closing = True |
| 684 | self._conn_lost += 1 |
| 685 | self._loop.remove_reader(self._sock_fd) |
| 686 | |
| 687 | |
| 688 | class _SelectorDatagramTransport(_SelectorTransport): |
| 689 | |
| 690 | def __init__(self, loop, sock, protocol, address=None, extra=None): |
| 691 | super().__init__(loop, sock, protocol, extra) |
| 692 | |
| 693 | self._address = address |
| 694 | self._loop.add_reader(self._sock_fd, self._read_ready) |
| 695 | self._loop.call_soon(self._protocol.connection_made, self) |
| 696 | |
| 697 | def _read_ready(self): |
| 698 | try: |
| 699 | data, addr = self._sock.recvfrom(self.max_size) |
| 700 | except (BlockingIOError, InterruptedError): |
| 701 | pass |
| 702 | except Exception as exc: |
| 703 | self._fatal_error(exc) |
| 704 | else: |
| 705 | self._protocol.datagram_received(data, addr) |
| 706 | |
| 707 | def sendto(self, data, addr=None): |
| 708 | assert isinstance(data, bytes), repr(type(data)) |
| 709 | if not data: |
| 710 | return |
| 711 | |
| 712 | if self._address: |
| 713 | assert addr in (None, self._address) |
| 714 | |
| 715 | if self._conn_lost and self._address: |
| 716 | if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| 717 | asyncio_log.warning('socket.send() raised exception.') |
| 718 | self._conn_lost += 1 |
| 719 | return |
| 720 | |
| 721 | if not self._buffer: |
| 722 | # Attempt to send it right away first. |
| 723 | try: |
| 724 | if self._address: |
| 725 | self._sock.send(data) |
| 726 | else: |
| 727 | self._sock.sendto(data, addr) |
| 728 | return |
| 729 | except ConnectionRefusedError as exc: |
| 730 | if self._address: |
| 731 | self._fatal_error(exc) |
| 732 | return |
| 733 | except (BlockingIOError, InterruptedError): |
| 734 | self._loop.add_writer(self._sock_fd, self._sendto_ready) |
| 735 | except Exception as exc: |
| 736 | self._fatal_error(exc) |
| 737 | return |
| 738 | |
| 739 | self._buffer.append((data, addr)) |
| 740 | |
| 741 | def _sendto_ready(self): |
| 742 | while self._buffer: |
| 743 | data, addr = self._buffer.popleft() |
| 744 | try: |
| 745 | if self._address: |
| 746 | self._sock.send(data) |
| 747 | else: |
| 748 | self._sock.sendto(data, addr) |
| 749 | except ConnectionRefusedError as exc: |
| 750 | if self._address: |
| 751 | self._fatal_error(exc) |
| 752 | return |
| 753 | except (BlockingIOError, InterruptedError): |
| 754 | self._buffer.appendleft((data, addr)) # Try again later. |
| 755 | break |
| 756 | except Exception as exc: |
| 757 | self._fatal_error(exc) |
| 758 | return |
| 759 | |
| 760 | if not self._buffer: |
| 761 | self._loop.remove_writer(self._sock_fd) |
| 762 | if self._closing: |
| 763 | self._call_connection_lost(None) |
| 764 | |
| 765 | def _force_close(self, exc): |
| 766 | if self._address and isinstance(exc, ConnectionRefusedError): |
| 767 | self._protocol.connection_refused(exc) |
| 768 | |
| 769 | super()._force_close(exc) |