| """Event loop using a selector and related classes. |
| |
| A selector is a "notify-when-ready" multiplexer. For a subclass which |
| also includes support for signal handling, see the unix_events sub-module. |
| """ |
| |
| import collections |
| import errno |
| import socket |
| try: |
| import ssl |
| except ImportError: # pragma: no cover |
| ssl = None |
| |
| from . import base_events |
| from . import constants |
| from . import events |
| from . import futures |
| from . import selectors |
| from . import transports |
| from .log import logger |
| |
| |
| class BaseSelectorEventLoop(base_events.BaseEventLoop): |
| """Selector event loop. |
| |
| See events.EventLoop for API specification. |
| """ |
| |
| def __init__(self, selector=None): |
| super().__init__() |
| |
| if selector is None: |
| selector = selectors.DefaultSelector() |
| logger.debug('Using selector: %s', selector.__class__.__name__) |
| self._selector = selector |
| self._make_self_pipe() |
| |
| def _make_socket_transport(self, sock, protocol, waiter=None, *, |
| extra=None, server=None): |
| return _SelectorSocketTransport(self, sock, protocol, waiter, |
| extra, server) |
| |
| def _make_ssl_transport(self, rawsock, protocol, sslcontext, waiter, *, |
| server_side=False, server_hostname=None, |
| extra=None, server=None): |
| return _SelectorSslTransport( |
| self, rawsock, protocol, sslcontext, waiter, |
| server_side, server_hostname, extra, server) |
| |
| def _make_datagram_transport(self, sock, protocol, |
| address=None, extra=None): |
| return _SelectorDatagramTransport(self, sock, protocol, address, extra) |
| |
| def close(self): |
| if self._selector is not None: |
| self._close_self_pipe() |
| self._selector.close() |
| self._selector = None |
| super().close() |
| |
| def _socketpair(self): |
| raise NotImplementedError |
| |
| def _close_self_pipe(self): |
| self.remove_reader(self._ssock.fileno()) |
| self._ssock.close() |
| self._ssock = None |
| self._csock.close() |
| self._csock = None |
| self._internal_fds -= 1 |
| |
| def _make_self_pipe(self): |
| # A self-socket, really. :-) |
| self._ssock, self._csock = self._socketpair() |
| self._ssock.setblocking(False) |
| self._csock.setblocking(False) |
| self._internal_fds += 1 |
| self.add_reader(self._ssock.fileno(), self._read_from_self) |
| |
| def _read_from_self(self): |
| try: |
| self._ssock.recv(1) |
| except (BlockingIOError, InterruptedError): |
| pass |
| |
| def _write_to_self(self): |
| try: |
| self._csock.send(b'x') |
| except (BlockingIOError, InterruptedError): |
| pass |
| |
| def _start_serving(self, protocol_factory, sock, |
| sslcontext=None, server=None): |
| self.add_reader(sock.fileno(), self._accept_connection, |
| protocol_factory, sock, sslcontext, server) |
| |
| def _accept_connection(self, protocol_factory, sock, |
| sslcontext=None, server=None): |
| try: |
| conn, addr = sock.accept() |
| conn.setblocking(False) |
| except (BlockingIOError, InterruptedError, ConnectionAbortedError): |
| pass # False alarm. |
| except OSError as exc: |
| # There's nowhere to send the error, so just log it. |
| # TODO: Someone will want an error handler for this. |
| if exc.errno in (errno.EMFILE, errno.ENFILE, |
| errno.ENOBUFS, errno.ENOMEM): |
| # Some platforms (e.g. Linux keep reporting the FD as |
| # ready, so we remove the read handler temporarily. |
| # We'll try again in a while. |
| logger.exception('Accept out of system resource (%s)', exc) |
| self.remove_reader(sock.fileno()) |
| self.call_later(constants.ACCEPT_RETRY_DELAY, |
| self._start_serving, |
| protocol_factory, sock, sslcontext, server) |
| else: |
| raise # The event loop will catch, log and ignore it. |
| else: |
| if sslcontext: |
| self._make_ssl_transport( |
| conn, protocol_factory(), sslcontext, None, |
| server_side=True, extra={'peername': addr}, server=server) |
| else: |
| self._make_socket_transport( |
| conn, protocol_factory(), extra={'peername': addr}, |
| server=server) |
| # It's now up to the protocol to handle the connection. |
| |
| def add_reader(self, fd, callback, *args): |
| """Add a reader callback.""" |
| handle = events.make_handle(callback, args) |
| try: |
| key = self._selector.get_key(fd) |
| except KeyError: |
| self._selector.register(fd, selectors.EVENT_READ, |
| (handle, None)) |
| else: |
| mask, (reader, writer) = key.events, key.data |
| self._selector.modify(fd, mask | selectors.EVENT_READ, |
| (handle, writer)) |
| if reader is not None: |
| reader.cancel() |
| |
| def remove_reader(self, fd): |
| """Remove a reader callback.""" |
| try: |
| key = self._selector.get_key(fd) |
| except KeyError: |
| return False |
| else: |
| mask, (reader, writer) = key.events, key.data |
| mask &= ~selectors.EVENT_READ |
| if not mask: |
| self._selector.unregister(fd) |
| else: |
| self._selector.modify(fd, mask, (None, writer)) |
| |
| if reader is not None: |
| reader.cancel() |
| return True |
| else: |
| return False |
| |
| def add_writer(self, fd, callback, *args): |
| """Add a writer callback..""" |
| handle = events.make_handle(callback, args) |
| try: |
| key = self._selector.get_key(fd) |
| except KeyError: |
| self._selector.register(fd, selectors.EVENT_WRITE, |
| (None, handle)) |
| else: |
| mask, (reader, writer) = key.events, key.data |
| self._selector.modify(fd, mask | selectors.EVENT_WRITE, |
| (reader, handle)) |
| if writer is not None: |
| writer.cancel() |
| |
| def remove_writer(self, fd): |
| """Remove a writer callback.""" |
| try: |
| key = self._selector.get_key(fd) |
| except KeyError: |
| return False |
| else: |
| mask, (reader, writer) = key.events, key.data |
| # Remove both writer and connector. |
| mask &= ~selectors.EVENT_WRITE |
| if not mask: |
| self._selector.unregister(fd) |
| else: |
| self._selector.modify(fd, mask, (reader, None)) |
| |
| if writer is not None: |
| writer.cancel() |
| return True |
| else: |
| return False |
| |
| def sock_recv(self, sock, n): |
| """XXX""" |
| fut = futures.Future(loop=self) |
| self._sock_recv(fut, False, sock, n) |
| return fut |
| |
| def _sock_recv(self, fut, registered, sock, n): |
| fd = sock.fileno() |
| if registered: |
| # Remove the callback early. It should be rare that the |
| # selector says the fd is ready but the call still returns |
| # EAGAIN, and I am willing to take a hit in that case in |
| # order to simplify the common case. |
| self.remove_reader(fd) |
| if fut.cancelled(): |
| return |
| try: |
| data = sock.recv(n) |
| except (BlockingIOError, InterruptedError): |
| self.add_reader(fd, self._sock_recv, fut, True, sock, n) |
| except Exception as exc: |
| fut.set_exception(exc) |
| else: |
| fut.set_result(data) |
| |
| def sock_sendall(self, sock, data): |
| """XXX""" |
| fut = futures.Future(loop=self) |
| if data: |
| self._sock_sendall(fut, False, sock, data) |
| else: |
| fut.set_result(None) |
| return fut |
| |
| def _sock_sendall(self, fut, registered, sock, data): |
| fd = sock.fileno() |
| |
| if registered: |
| self.remove_writer(fd) |
| if fut.cancelled(): |
| return |
| |
| try: |
| n = sock.send(data) |
| except (BlockingIOError, InterruptedError): |
| n = 0 |
| except Exception as exc: |
| fut.set_exception(exc) |
| return |
| |
| if n == len(data): |
| fut.set_result(None) |
| else: |
| if n: |
| data = data[n:] |
| self.add_writer(fd, self._sock_sendall, fut, True, sock, data) |
| |
| def sock_connect(self, sock, address): |
| """XXX""" |
| # That address better not require a lookup! We're not calling |
| # self.getaddrinfo() for you here. But verifying this is |
| # complicated; the socket module doesn't have a pattern for |
| # IPv6 addresses (there are too many forms, apparently). |
| fut = futures.Future(loop=self) |
| self._sock_connect(fut, False, sock, address) |
| return fut |
| |
| def _sock_connect(self, fut, registered, sock, address): |
| # TODO: Use getaddrinfo() to look up the address, to avoid the |
| # trap of hanging the entire event loop when the address |
| # requires doing a DNS lookup. (OTOH, the caller should |
| # already have done this, so it would be nice if we could |
| # easily tell whether the address needs looking up or not. I |
| # know how to do this for IPv4, but IPv6 addresses have many |
| # syntaxes.) |
| fd = sock.fileno() |
| if registered: |
| self.remove_writer(fd) |
| if fut.cancelled(): |
| return |
| try: |
| if not registered: |
| # First time around. |
| sock.connect(address) |
| else: |
| err = sock.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR) |
| if err != 0: |
| # Jump to the except clause below. |
| raise OSError(err, 'Connect call failed %s' % (address,)) |
| except (BlockingIOError, InterruptedError): |
| self.add_writer(fd, self._sock_connect, fut, True, sock, address) |
| except Exception as exc: |
| fut.set_exception(exc) |
| else: |
| fut.set_result(None) |
| |
| def sock_accept(self, sock): |
| """XXX""" |
| fut = futures.Future(loop=self) |
| self._sock_accept(fut, False, sock) |
| return fut |
| |
| def _sock_accept(self, fut, registered, sock): |
| fd = sock.fileno() |
| if registered: |
| self.remove_reader(fd) |
| if fut.cancelled(): |
| return |
| try: |
| conn, address = sock.accept() |
| conn.setblocking(False) |
| except (BlockingIOError, InterruptedError): |
| self.add_reader(fd, self._sock_accept, fut, True, sock) |
| except Exception as exc: |
| fut.set_exception(exc) |
| else: |
| fut.set_result((conn, address)) |
| |
| def _process_events(self, event_list): |
| for key, mask in event_list: |
| fileobj, (reader, writer) = key.fileobj, key.data |
| if mask & selectors.EVENT_READ and reader is not None: |
| if reader._cancelled: |
| self.remove_reader(fileobj) |
| else: |
| self._add_callback(reader) |
| if mask & selectors.EVENT_WRITE and writer is not None: |
| if writer._cancelled: |
| self.remove_writer(fileobj) |
| else: |
| self._add_callback(writer) |
| |
| def _stop_serving(self, sock): |
| self.remove_reader(sock.fileno()) |
| sock.close() |
| |
| |
| class _SelectorTransport(transports.Transport): |
| |
| max_size = 256 * 1024 # Buffer size passed to recv(). |
| |
| _buffer_factory = bytearray # Constructs initial value for self._buffer. |
| |
| def __init__(self, loop, sock, protocol, extra, server=None): |
| super().__init__(extra) |
| self._extra['socket'] = sock |
| self._extra['sockname'] = sock.getsockname() |
| if 'peername' not in self._extra: |
| try: |
| self._extra['peername'] = sock.getpeername() |
| except socket.error: |
| self._extra['peername'] = None |
| self._loop = loop |
| self._sock = sock |
| self._sock_fd = sock.fileno() |
| self._protocol = protocol |
| self._server = server |
| self._buffer = self._buffer_factory() |
| self._conn_lost = 0 # Set when call to connection_lost scheduled. |
| self._closing = False # Set when close() called. |
| self._protocol_paused = False |
| self.set_write_buffer_limits() |
| if self._server is not None: |
| self._server.attach(self) |
| |
| def abort(self): |
| self._force_close(None) |
| |
| def close(self): |
| if self._closing: |
| return |
| self._closing = True |
| self._loop.remove_reader(self._sock_fd) |
| if not self._buffer: |
| self._conn_lost += 1 |
| self._loop.call_soon(self._call_connection_lost, None) |
| |
| def _fatal_error(self, exc): |
| # Should be called from exception handler only. |
| if not isinstance(exc, (BrokenPipeError, ConnectionResetError)): |
| logger.exception('Fatal error for %s', self) |
| self._force_close(exc) |
| |
| def _force_close(self, exc): |
| if self._conn_lost: |
| return |
| if self._buffer: |
| self._buffer.clear() |
| self._loop.remove_writer(self._sock_fd) |
| if not self._closing: |
| self._closing = True |
| self._loop.remove_reader(self._sock_fd) |
| self._conn_lost += 1 |
| self._loop.call_soon(self._call_connection_lost, exc) |
| |
| def _call_connection_lost(self, exc): |
| try: |
| self._protocol.connection_lost(exc) |
| finally: |
| self._sock.close() |
| self._sock = None |
| self._protocol = None |
| self._loop = None |
| server = self._server |
| if server is not None: |
| server.detach(self) |
| self._server = None |
| |
| def _maybe_pause_protocol(self): |
| size = self.get_write_buffer_size() |
| if size <= self._high_water: |
| return |
| if not self._protocol_paused: |
| self._protocol_paused = True |
| try: |
| self._protocol.pause_writing() |
| except Exception: |
| logger.exception('pause_writing() failed') |
| |
| def _maybe_resume_protocol(self): |
| if (self._protocol_paused and |
| self.get_write_buffer_size() <= self._low_water): |
| self._protocol_paused = False |
| try: |
| self._protocol.resume_writing() |
| except Exception: |
| logger.exception('resume_writing() failed') |
| |
| def set_write_buffer_limits(self, high=None, low=None): |
| if high is None: |
| if low is None: |
| high = 64*1024 |
| else: |
| high = 4*low |
| if low is None: |
| low = high // 4 |
| if not high >= low >= 0: |
| raise ValueError('high (%r) must be >= low (%r) must be >= 0' % |
| (high, low)) |
| self._high_water = high |
| self._low_water = low |
| |
| def get_write_buffer_size(self): |
| return len(self._buffer) |
| |
| |
| class _SelectorSocketTransport(_SelectorTransport): |
| |
| def __init__(self, loop, sock, protocol, waiter=None, |
| extra=None, server=None): |
| super().__init__(loop, sock, protocol, extra, server) |
| self._eof = False |
| self._paused = False |
| |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| self._loop.call_soon(self._protocol.connection_made, self) |
| if waiter is not None: |
| self._loop.call_soon(waiter.set_result, None) |
| |
| def pause_reading(self): |
| if self._closing: |
| raise RuntimeError('Cannot pause_reading() when closing') |
| if self._paused: |
| raise RuntimeError('Already paused') |
| self._paused = True |
| self._loop.remove_reader(self._sock_fd) |
| |
| def resume_reading(self): |
| if not self._paused: |
| raise RuntimeError('Not paused') |
| self._paused = False |
| if self._closing: |
| return |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| |
| def _read_ready(self): |
| try: |
| data = self._sock.recv(self.max_size) |
| except (BlockingIOError, InterruptedError): |
| pass |
| except Exception as exc: |
| self._fatal_error(exc) |
| else: |
| if data: |
| self._protocol.data_received(data) |
| else: |
| keep_open = self._protocol.eof_received() |
| if keep_open: |
| # We're keeping the connection open so the |
| # protocol can write more, but we still can't |
| # receive more, so remove the reader callback. |
| self._loop.remove_reader(self._sock_fd) |
| else: |
| self.close() |
| |
| def write(self, data): |
| if not isinstance(data, (bytes, bytearray, memoryview)): |
| raise TypeError('data argument must be byte-ish (%r)', |
| type(data)) |
| if self._eof: |
| raise RuntimeError('Cannot call write() after write_eof()') |
| if not data: |
| return |
| |
| if self._conn_lost: |
| if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| logger.warning('socket.send() raised exception.') |
| self._conn_lost += 1 |
| return |
| |
| if not self._buffer: |
| # Optimization: try to send now. |
| try: |
| n = self._sock.send(data) |
| except (BlockingIOError, InterruptedError): |
| pass |
| except Exception as exc: |
| self._fatal_error(exc) |
| return |
| else: |
| data = data[n:] |
| if not data: |
| return |
| # Not all was written; register write handler. |
| self._loop.add_writer(self._sock_fd, self._write_ready) |
| |
| # Add it to the buffer. |
| self._buffer.extend(data) |
| self._maybe_pause_protocol() |
| |
| def _write_ready(self): |
| assert self._buffer, 'Data should not be empty' |
| |
| try: |
| n = self._sock.send(self._buffer) |
| except (BlockingIOError, InterruptedError): |
| pass |
| except Exception as exc: |
| self._loop.remove_writer(self._sock_fd) |
| self._buffer.clear() |
| self._fatal_error(exc) |
| else: |
| if n: |
| del self._buffer[:n] |
| self._maybe_resume_protocol() # May append to buffer. |
| if not self._buffer: |
| self._loop.remove_writer(self._sock_fd) |
| if self._closing: |
| self._call_connection_lost(None) |
| elif self._eof: |
| self._sock.shutdown(socket.SHUT_WR) |
| |
| def write_eof(self): |
| if self._eof: |
| return |
| self._eof = True |
| if not self._buffer: |
| self._sock.shutdown(socket.SHUT_WR) |
| |
| def can_write_eof(self): |
| return True |
| |
| |
| class _SelectorSslTransport(_SelectorTransport): |
| |
| _buffer_factory = bytearray |
| |
| def __init__(self, loop, rawsock, protocol, sslcontext, waiter=None, |
| server_side=False, server_hostname=None, |
| extra=None, server=None): |
| if ssl is None: |
| raise RuntimeError('stdlib ssl module not available') |
| |
| if server_side: |
| if not sslcontext: |
| raise ValueError('Server side ssl needs a valid SSLContext') |
| else: |
| if not sslcontext: |
| # Client side may pass ssl=True to use a default |
| # context; in that case the sslcontext passed is None. |
| # The default is the same as used by urllib with |
| # cadefault=True. |
| if hasattr(ssl, '_create_stdlib_context'): |
| sslcontext = ssl._create_stdlib_context( |
| cert_reqs=ssl.CERT_REQUIRED, |
| check_hostname=bool(server_hostname)) |
| else: |
| # Fallback for Python 3.3. |
| sslcontext = ssl.SSLContext(ssl.PROTOCOL_SSLv23) |
| sslcontext.options |= ssl.OP_NO_SSLv2 |
| sslcontext.set_default_verify_paths() |
| sslcontext.verify_mode = ssl.CERT_REQUIRED |
| |
| wrap_kwargs = { |
| 'server_side': server_side, |
| 'do_handshake_on_connect': False, |
| } |
| if server_hostname and not server_side and ssl.HAS_SNI: |
| wrap_kwargs['server_hostname'] = server_hostname |
| sslsock = sslcontext.wrap_socket(rawsock, **wrap_kwargs) |
| |
| super().__init__(loop, sslsock, protocol, extra, server) |
| |
| self._server_hostname = server_hostname |
| self._waiter = waiter |
| self._rawsock = rawsock |
| self._sslcontext = sslcontext |
| self._paused = False |
| |
| # SSL-specific extra info. (peercert is set later) |
| self._extra.update(sslcontext=sslcontext) |
| |
| self._on_handshake() |
| |
| def _on_handshake(self): |
| try: |
| self._sock.do_handshake() |
| except ssl.SSLWantReadError: |
| self._loop.add_reader(self._sock_fd, self._on_handshake) |
| return |
| except ssl.SSLWantWriteError: |
| self._loop.add_writer(self._sock_fd, self._on_handshake) |
| return |
| except Exception as exc: |
| self._loop.remove_reader(self._sock_fd) |
| self._loop.remove_writer(self._sock_fd) |
| self._sock.close() |
| if self._waiter is not None: |
| self._waiter.set_exception(exc) |
| return |
| except BaseException as exc: |
| self._loop.remove_reader(self._sock_fd) |
| self._loop.remove_writer(self._sock_fd) |
| self._sock.close() |
| if self._waiter is not None: |
| self._waiter.set_exception(exc) |
| raise |
| |
| self._loop.remove_reader(self._sock_fd) |
| self._loop.remove_writer(self._sock_fd) |
| |
| peercert = self._sock.getpeercert() |
| if not hasattr(self._sslcontext, 'check_hostname'): |
| # Verify hostname if requested, Python 3.4+ uses check_hostname |
| # and checks the hostname in do_handshake() |
| if (self._server_hostname and |
| self._sslcontext.verify_mode != ssl.CERT_NONE): |
| try: |
| ssl.match_hostname(peercert, self._server_hostname) |
| except Exception as exc: |
| self._sock.close() |
| if self._waiter is not None: |
| self._waiter.set_exception(exc) |
| return |
| |
| # Add extra info that becomes available after handshake. |
| self._extra.update(peercert=peercert, |
| cipher=self._sock.cipher(), |
| compression=self._sock.compression(), |
| ) |
| |
| self._read_wants_write = False |
| self._write_wants_read = False |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| self._loop.call_soon(self._protocol.connection_made, self) |
| if self._waiter is not None: |
| self._loop.call_soon(self._waiter.set_result, None) |
| |
| def pause_reading(self): |
| # XXX This is a bit icky, given the comment at the top of |
| # _read_ready(). Is it possible to evoke a deadlock? I don't |
| # know, although it doesn't look like it; write() will still |
| # accept more data for the buffer and eventually the app will |
| # call resume_reading() again, and things will flow again. |
| |
| if self._closing: |
| raise RuntimeError('Cannot pause_reading() when closing') |
| if self._paused: |
| raise RuntimeError('Already paused') |
| self._paused = True |
| self._loop.remove_reader(self._sock_fd) |
| |
| def resume_reading(self): |
| if not self._paused: |
| raise ('Not paused') |
| self._paused = False |
| if self._closing: |
| return |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| |
| def _read_ready(self): |
| if self._write_wants_read: |
| self._write_wants_read = False |
| self._write_ready() |
| |
| if self._buffer: |
| self._loop.add_writer(self._sock_fd, self._write_ready) |
| |
| try: |
| data = self._sock.recv(self.max_size) |
| except (BlockingIOError, InterruptedError, ssl.SSLWantReadError): |
| pass |
| except ssl.SSLWantWriteError: |
| self._read_wants_write = True |
| self._loop.remove_reader(self._sock_fd) |
| self._loop.add_writer(self._sock_fd, self._write_ready) |
| except Exception as exc: |
| self._fatal_error(exc) |
| else: |
| if data: |
| self._protocol.data_received(data) |
| else: |
| try: |
| keep_open = self._protocol.eof_received() |
| if keep_open: |
| logger.warning('returning true from eof_received() ' |
| 'has no effect when using ssl') |
| finally: |
| self.close() |
| |
| def _write_ready(self): |
| if self._read_wants_write: |
| self._read_wants_write = False |
| self._read_ready() |
| |
| if not (self._paused or self._closing): |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| |
| if self._buffer: |
| try: |
| n = self._sock.send(self._buffer) |
| except (BlockingIOError, InterruptedError, |
| ssl.SSLWantWriteError): |
| n = 0 |
| except ssl.SSLWantReadError: |
| n = 0 |
| self._loop.remove_writer(self._sock_fd) |
| self._write_wants_read = True |
| except Exception as exc: |
| self._loop.remove_writer(self._sock_fd) |
| self._buffer.clear() |
| self._fatal_error(exc) |
| return |
| |
| if n: |
| del self._buffer[:n] |
| |
| self._maybe_resume_protocol() # May append to buffer. |
| |
| if not self._buffer: |
| self._loop.remove_writer(self._sock_fd) |
| if self._closing: |
| self._call_connection_lost(None) |
| |
| def write(self, data): |
| if not isinstance(data, (bytes, bytearray, memoryview)): |
| raise TypeError('data argument must be byte-ish (%r)', |
| type(data)) |
| if not data: |
| return |
| |
| if self._conn_lost: |
| if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| logger.warning('socket.send() raised exception.') |
| self._conn_lost += 1 |
| return |
| |
| if not self._buffer: |
| self._loop.add_writer(self._sock_fd, self._write_ready) |
| |
| # Add it to the buffer. |
| self._buffer.extend(data) |
| self._maybe_pause_protocol() |
| |
| def can_write_eof(self): |
| return False |
| |
| |
| class _SelectorDatagramTransport(_SelectorTransport): |
| |
| _buffer_factory = collections.deque |
| |
| def __init__(self, loop, sock, protocol, address=None, extra=None): |
| super().__init__(loop, sock, protocol, extra) |
| self._address = address |
| self._loop.add_reader(self._sock_fd, self._read_ready) |
| self._loop.call_soon(self._protocol.connection_made, self) |
| |
| def get_write_buffer_size(self): |
| return sum(len(data) for data, _ in self._buffer) |
| |
| def _read_ready(self): |
| try: |
| data, addr = self._sock.recvfrom(self.max_size) |
| except (BlockingIOError, InterruptedError): |
| pass |
| except OSError as exc: |
| self._protocol.error_received(exc) |
| except Exception as exc: |
| self._fatal_error(exc) |
| else: |
| self._protocol.datagram_received(data, addr) |
| |
| def sendto(self, data, addr=None): |
| if not isinstance(data, (bytes, bytearray, memoryview)): |
| raise TypeError('data argument must be byte-ish (%r)', |
| type(data)) |
| if not data: |
| return |
| |
| if self._address and addr not in (None, self._address): |
| raise ValueError('Invalid address: must be None or %s' % |
| (self._address,)) |
| |
| if self._conn_lost and self._address: |
| if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES: |
| logger.warning('socket.send() raised exception.') |
| self._conn_lost += 1 |
| return |
| |
| if not self._buffer: |
| # Attempt to send it right away first. |
| try: |
| if self._address: |
| self._sock.send(data) |
| else: |
| self._sock.sendto(data, addr) |
| return |
| except (BlockingIOError, InterruptedError): |
| self._loop.add_writer(self._sock_fd, self._sendto_ready) |
| except OSError as exc: |
| self._protocol.error_received(exc) |
| return |
| except Exception as exc: |
| self._fatal_error(exc) |
| return |
| |
| # Ensure that what we buffer is immutable. |
| self._buffer.append((bytes(data), addr)) |
| self._maybe_pause_protocol() |
| |
| def _sendto_ready(self): |
| while self._buffer: |
| data, addr = self._buffer.popleft() |
| try: |
| if self._address: |
| self._sock.send(data) |
| else: |
| self._sock.sendto(data, addr) |
| except (BlockingIOError, InterruptedError): |
| self._buffer.appendleft((data, addr)) # Try again later. |
| break |
| except OSError as exc: |
| self._protocol.error_received(exc) |
| return |
| except Exception as exc: |
| self._fatal_error(exc) |
| return |
| |
| self._maybe_resume_protocol() # May append to buffer. |
| if not self._buffer: |
| self._loop.remove_writer(self._sock_fd) |
| if self._closing: |
| self._call_connection_lost(None) |