| """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. |
| """ |
| |
| __all__ = ['BaseSelectorEventLoop'] |
| |
| import collections |
| import errno |
| import functools |
| import socket |
| import warnings |
| import weakref |
| try: |
| import ssl |
| except ImportError: # pragma: no cover |
| ssl = None |
| |
| from . import base_events |
| from . import compat |
| from . import constants |
| from . import events |
| from . import futures |
| from . import selectors |
| from . import transports |
| from . import sslproto |
| from .coroutines import coroutine |
| from .log import logger |
| |
| |
| def _test_selector_event(selector, fd, event): |
| # Test if the selector is monitoring 'event' events |
| # for the file descriptor 'fd'. |
| try: |
| key = selector.get_key(fd) |
| except KeyError: |
| return False |
| else: |
| return bool(key.events & event) |
| |
| |
| if hasattr(socket, 'TCP_NODELAY'): |
| def _set_nodelay(sock): |
| if (sock.family in {socket.AF_INET, socket.AF_INET6} and |
| sock.type == socket.SOCK_STREAM and |
| sock.proto == socket.IPPROTO_TCP): |
| sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1) |
| else: |
| def _set_nodelay(sock): |
| pass |
| |
| |
| 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() |
| self._transports = weakref.WeakValueDictionary() |
| |
| 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=None, |
| *, server_side=False, server_hostname=None, |
| extra=None, server=None): |
| if not sslproto._is_sslproto_available(): |
| return self._make_legacy_ssl_transport( |
| rawsock, protocol, sslcontext, waiter, |
| server_side=server_side, server_hostname=server_hostname, |
| extra=extra, server=server) |
| |
| ssl_protocol = sslproto.SSLProtocol(self, protocol, sslcontext, waiter, |
| server_side, server_hostname) |
| _SelectorSocketTransport(self, rawsock, ssl_protocol, |
| extra=extra, server=server) |
| return ssl_protocol._app_transport |
| |
| def _make_legacy_ssl_transport(self, rawsock, protocol, sslcontext, |
| waiter, *, |
| server_side=False, server_hostname=None, |
| extra=None, server=None): |
| # Use the legacy API: SSL_write, SSL_read, etc. The legacy API is used |
| # on Python 3.4 and older, when ssl.MemoryBIO is not available. |
| return _SelectorSslTransport( |
| self, rawsock, protocol, sslcontext, waiter, |
| server_side, server_hostname, extra, server) |
| |
| def _make_datagram_transport(self, sock, protocol, |
| address=None, waiter=None, extra=None): |
| return _SelectorDatagramTransport(self, sock, protocol, |
| address, waiter, extra) |
| |
| def close(self): |
| if self.is_running(): |
| raise RuntimeError("Cannot close a running event loop") |
| if self.is_closed(): |
| return |
| self._close_self_pipe() |
| super().close() |
| if self._selector is not None: |
| self._selector.close() |
| self._selector = None |
| |
| 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 _process_self_data(self, data): |
| pass |
| |
| def _read_from_self(self): |
| while True: |
| try: |
| data = self._ssock.recv(4096) |
| if not data: |
| break |
| self._process_self_data(data) |
| except InterruptedError: |
| continue |
| except BlockingIOError: |
| break |
| |
| def _write_to_self(self): |
| # This may be called from a different thread, possibly after |
| # _close_self_pipe() has been called or even while it is |
| # running. Guard for self._csock being None or closed. When |
| # a socket is closed, send() raises OSError (with errno set to |
| # EBADF, but let's not rely on the exact error code). |
| csock = self._csock |
| if csock is not None: |
| try: |
| csock.send(b'\0') |
| except OSError: |
| if self._debug: |
| logger.debug("Fail to write a null byte into the " |
| "self-pipe socket", |
| exc_info=True) |
| |
| def _start_serving(self, protocol_factory, sock, |
| sslcontext=None, server=None, backlog=100): |
| self._add_reader(sock.fileno(), self._accept_connection, |
| protocol_factory, sock, sslcontext, server, backlog) |
| |
| def _accept_connection(self, protocol_factory, sock, |
| sslcontext=None, server=None, backlog=100): |
| # This method is only called once for each event loop tick where the |
| # listening socket has triggered an EVENT_READ. There may be multiple |
| # connections waiting for an .accept() so it is called in a loop. |
| # See https://bugs.python.org/issue27906 for more details. |
| for _ in range(backlog): |
| try: |
| conn, addr = sock.accept() |
| if self._debug: |
| logger.debug("%r got a new connection from %r: %r", |
| server, addr, conn) |
| conn.setblocking(False) |
| except (BlockingIOError, InterruptedError, ConnectionAbortedError): |
| # Early exit because the socket accept buffer is empty. |
| return None |
| except OSError as exc: |
| # There's nowhere to send the error, so just log it. |
| 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. |
| self.call_exception_handler({ |
| 'message': 'socket.accept() out of system resource', |
| 'exception': exc, |
| 'socket': sock, |
| }) |
| self._remove_reader(sock.fileno()) |
| self.call_later(constants.ACCEPT_RETRY_DELAY, |
| self._start_serving, |
| protocol_factory, sock, sslcontext, server, |
| backlog) |
| else: |
| raise # The event loop will catch, log and ignore it. |
| else: |
| extra = {'peername': addr} |
| accept = self._accept_connection2(protocol_factory, conn, extra, |
| sslcontext, server) |
| self.create_task(accept) |
| |
| @coroutine |
| def _accept_connection2(self, protocol_factory, conn, extra, |
| sslcontext=None, server=None): |
| protocol = None |
| transport = None |
| try: |
| protocol = protocol_factory() |
| waiter = self.create_future() |
| if sslcontext: |
| transport = self._make_ssl_transport( |
| conn, protocol, sslcontext, waiter=waiter, |
| server_side=True, extra=extra, server=server) |
| else: |
| transport = self._make_socket_transport( |
| conn, protocol, waiter=waiter, extra=extra, |
| server=server) |
| |
| try: |
| yield from waiter |
| except: |
| transport.close() |
| raise |
| |
| # It's now up to the protocol to handle the connection. |
| except Exception as exc: |
| if self._debug: |
| context = { |
| 'message': ('Error on transport creation ' |
| 'for incoming connection'), |
| 'exception': exc, |
| } |
| if protocol is not None: |
| context['protocol'] = protocol |
| if transport is not None: |
| context['transport'] = transport |
| self.call_exception_handler(context) |
| |
| def _ensure_fd_no_transport(self, fd): |
| try: |
| transport = self._transports[fd] |
| except KeyError: |
| pass |
| else: |
| if not transport.is_closing(): |
| raise RuntimeError( |
| 'File descriptor {!r} is used by transport {!r}'.format( |
| fd, transport)) |
| |
| def _add_reader(self, fd, callback, *args): |
| self._check_closed() |
| handle = events.Handle(callback, args, self) |
| 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): |
| if self.is_closed(): |
| return False |
| 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): |
| self._check_closed() |
| handle = events.Handle(callback, args, self) |
| 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.""" |
| if self.is_closed(): |
| return False |
| 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 add_reader(self, fd, callback, *args): |
| """Add a reader callback.""" |
| self._ensure_fd_no_transport(fd) |
| return self._add_reader(fd, callback, *args) |
| |
| def remove_reader(self, fd): |
| """Remove a reader callback.""" |
| self._ensure_fd_no_transport(fd) |
| return self._remove_reader(fd) |
| |
| def add_writer(self, fd, callback, *args): |
| """Add a writer callback..""" |
| self._ensure_fd_no_transport(fd) |
| return self._add_writer(fd, callback, *args) |
| |
| def remove_writer(self, fd): |
| """Remove a writer callback.""" |
| self._ensure_fd_no_transport(fd) |
| return self._remove_writer(fd) |
| |
| def sock_recv(self, sock, n): |
| """Receive data from the socket. |
| |
| The return value is a bytes object representing the data received. |
| The maximum amount of data to be received at once is specified by |
| nbytes. |
| |
| This method is a coroutine. |
| """ |
| if self._debug and sock.gettimeout() != 0: |
| raise ValueError("the socket must be non-blocking") |
| fut = self.create_future() |
| self._sock_recv(fut, False, sock, n) |
| return fut |
| |
| def _sock_recv(self, fut, registered, sock, n): |
| # _sock_recv() can add itself as an I/O callback if the operation can't |
| # be done immediately. Don't use it directly, call sock_recv(). |
| 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): |
| """Send data to the socket. |
| |
| The socket must be connected to a remote socket. This method continues |
| to send data from data until either all data has been sent or an |
| error occurs. None is returned on success. On error, an exception is |
| raised, and there is no way to determine how much data, if any, was |
| successfully processed by the receiving end of the connection. |
| |
| This method is a coroutine. |
| """ |
| if self._debug and sock.gettimeout() != 0: |
| raise ValueError("the socket must be non-blocking") |
| fut = self.create_future() |
| 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) |
| |
| @coroutine |
| def sock_connect(self, sock, address): |
| """Connect to a remote socket at address. |
| |
| This method is a coroutine. |
| """ |
| if self._debug and sock.gettimeout() != 0: |
| raise ValueError("the socket must be non-blocking") |
| |
| if not hasattr(socket, 'AF_UNIX') or sock.family != socket.AF_UNIX: |
| resolved = base_events._ensure_resolved( |
| address, family=sock.family, proto=sock.proto, loop=self) |
| if not resolved.done(): |
| yield from resolved |
| _, _, _, _, address = resolved.result()[0] |
| |
| fut = self.create_future() |
| self._sock_connect(fut, sock, address) |
| return (yield from fut) |
| |
| def _sock_connect(self, fut, sock, address): |
| fd = sock.fileno() |
| try: |
| sock.connect(address) |
| except (BlockingIOError, InterruptedError): |
| # Issue #23618: When the C function connect() fails with EINTR, the |
| # connection runs in background. We have to wait until the socket |
| # becomes writable to be notified when the connection succeed or |
| # fails. |
| fut.add_done_callback( |
| functools.partial(self._sock_connect_done, fd)) |
| self.add_writer(fd, self._sock_connect_cb, fut, sock, address) |
| except Exception as exc: |
| fut.set_exception(exc) |
| else: |
| fut.set_result(None) |
| |
| def _sock_connect_done(self, fd, fut): |
| self.remove_writer(fd) |
| |
| def _sock_connect_cb(self, fut, sock, address): |
| if fut.cancelled(): |
| return |
| |
| try: |
| err = sock.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR) |
| if err != 0: |
| # Jump to any except clause below. |
| raise OSError(err, 'Connect call failed %s' % (address,)) |
| except (BlockingIOError, InterruptedError): |
| # socket is still registered, the callback will be retried later |
| pass |
| except Exception as exc: |
| fut.set_exception(exc) |
| else: |
| fut.set_result(None) |
| |
| def sock_accept(self, sock): |
| """Accept a connection. |
| |
| The socket must be bound to an address and listening for connections. |
| The return value is a pair (conn, address) where conn is a new socket |
| object usable to send and receive data on the connection, and address |
| is the address bound to the socket on the other end of the connection. |
| |
| This method is a coroutine. |
| """ |
| if self._debug and sock.gettimeout() != 0: |
| raise ValueError("the socket must be non-blocking") |
| fut = self.create_future() |
| 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._FlowControlMixin, |
| transports.Transport): |
| |
| max_size = 256 * 1024 # Buffer size passed to recv(). |
| |
| _buffer_factory = bytearray # Constructs initial value for self._buffer. |
| |
| # Attribute used in the destructor: it must be set even if the constructor |
| # is not called (see _SelectorSslTransport which may start by raising an |
| # exception) |
| _sock = None |
| |
| def __init__(self, loop, sock, protocol, extra=None, server=None): |
| super().__init__(extra, loop) |
| 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._sock = sock |
| self._sock_fd = sock.fileno() |
| self._protocol = protocol |
| self._protocol_connected = True |
| 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. |
| if self._server is not None: |
| self._server._attach() |
| loop._transports[self._sock_fd] = self |
| |
| def __repr__(self): |
| info = [self.__class__.__name__] |
| if self._sock is None: |
| info.append('closed') |
| elif self._closing: |
| info.append('closing') |
| info.append('fd=%s' % self._sock_fd) |
| # test if the transport was closed |
| if self._loop is not None and not self._loop.is_closed(): |
| polling = _test_selector_event(self._loop._selector, |
| self._sock_fd, selectors.EVENT_READ) |
| if polling: |
| info.append('read=polling') |
| else: |
| info.append('read=idle') |
| |
| polling = _test_selector_event(self._loop._selector, |
| self._sock_fd, |
| selectors.EVENT_WRITE) |
| if polling: |
| state = 'polling' |
| else: |
| state = 'idle' |
| |
| bufsize = self.get_write_buffer_size() |
| info.append('write=<%s, bufsize=%s>' % (state, bufsize)) |
| return '<%s>' % ' '.join(info) |
| |
| def abort(self): |
| self._force_close(None) |
| |
| def set_protocol(self, protocol): |
| self._protocol = protocol |
| |
| def get_protocol(self): |
| return self._protocol |
| |
| def is_closing(self): |
| return self._closing |
| |
| 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._remove_writer(self._sock_fd) |
| self._loop.call_soon(self._call_connection_lost, None) |
| |
| # On Python 3.3 and older, objects with a destructor part of a reference |
| # cycle are never destroyed. It's not more the case on Python 3.4 thanks |
| # to the PEP 442. |
| if compat.PY34: |
| def __del__(self): |
| if self._sock is not None: |
| warnings.warn("unclosed transport %r" % self, ResourceWarning, |
| source=self) |
| self._sock.close() |
| |
| def _fatal_error(self, exc, message='Fatal error on transport'): |
| # Should be called from exception handler only. |
| if isinstance(exc, base_events._FATAL_ERROR_IGNORE): |
| if self._loop.get_debug(): |
| logger.debug("%r: %s", self, message, exc_info=True) |
| else: |
| self._loop.call_exception_handler({ |
| 'message': message, |
| 'exception': exc, |
| 'transport': self, |
| 'protocol': self._protocol, |
| }) |
| 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: |
| if self._protocol_connected: |
| 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._server = None |
| |
| 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 |
| |
| # Disable the Nagle algorithm -- small writes will be |
| # sent without waiting for the TCP ACK. This generally |
| # decreases the latency (in some cases significantly.) |
| _set_nodelay(self._sock) |
| |
| self._loop.call_soon(self._protocol.connection_made, self) |
| # only start reading when connection_made() has been called |
| self._loop.call_soon(self._loop._add_reader, |
| self._sock_fd, self._read_ready) |
| if waiter is not None: |
| # only wake up the waiter when connection_made() has been called |
| self._loop.call_soon(futures._set_result_unless_cancelled, |
| waiter, 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) |
| if self._loop.get_debug(): |
| logger.debug("%r pauses reading", self) |
| |
| 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) |
| if self._loop.get_debug(): |
| logger.debug("%r resumes reading", self) |
| |
| def _read_ready(self): |
| if self._conn_lost: |
| return |
| try: |
| data = self._sock.recv(self.max_size) |
| except (BlockingIOError, InterruptedError): |
| pass |
| except Exception as exc: |
| self._fatal_error(exc, 'Fatal read error on socket transport') |
| else: |
| if data: |
| self._protocol.data_received(data) |
| else: |
| if self._loop.get_debug(): |
| logger.debug("%r received EOF", self) |
| 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 a bytes-like object, ' |
| 'not %r' % type(data).__name__) |
| 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, 'Fatal write error on socket transport') |
| 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' |
| |
| if self._conn_lost: |
| return |
| 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, 'Fatal write error on socket transport') |
| 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 not sslcontext: |
| sslcontext = sslproto._create_transport_context(server_side, server_hostname) |
| |
| wrap_kwargs = { |
| 'server_side': server_side, |
| 'do_handshake_on_connect': False, |
| } |
| if server_hostname and not server_side: |
| wrap_kwargs['server_hostname'] = server_hostname |
| sslsock = sslcontext.wrap_socket(rawsock, **wrap_kwargs) |
| |
| super().__init__(loop, sslsock, protocol, extra, server) |
| # the protocol connection is only made after the SSL handshake |
| self._protocol_connected = False |
| |
| self._server_hostname = server_hostname |
| self._waiter = waiter |
| self._sslcontext = sslcontext |
| self._paused = False |
| |
| # SSL-specific extra info. (peercert is set later) |
| self._extra.update(sslcontext=sslcontext) |
| |
| if self._loop.get_debug(): |
| logger.debug("%r starts SSL handshake", self) |
| start_time = self._loop.time() |
| else: |
| start_time = None |
| self._on_handshake(start_time) |
| |
| def _wakeup_waiter(self, exc=None): |
| if self._waiter is None: |
| return |
| if not self._waiter.cancelled(): |
| if exc is not None: |
| self._waiter.set_exception(exc) |
| else: |
| self._waiter.set_result(None) |
| self._waiter = None |
| |
| def _on_handshake(self, start_time): |
| try: |
| self._sock.do_handshake() |
| except ssl.SSLWantReadError: |
| self._loop._add_reader(self._sock_fd, |
| self._on_handshake, start_time) |
| return |
| except ssl.SSLWantWriteError: |
| self._loop._add_writer(self._sock_fd, |
| self._on_handshake, start_time) |
| return |
| except BaseException as exc: |
| if self._loop.get_debug(): |
| logger.warning("%r: SSL handshake failed", |
| self, exc_info=True) |
| self._loop._remove_reader(self._sock_fd) |
| self._loop._remove_writer(self._sock_fd) |
| self._sock.close() |
| self._wakeup_waiter(exc) |
| if isinstance(exc, Exception): |
| return |
| else: |
| 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: |
| if self._loop.get_debug(): |
| logger.warning("%r: SSL handshake failed " |
| "on matching the hostname", |
| self, exc_info=True) |
| self._sock.close() |
| self._wakeup_waiter(exc) |
| return |
| |
| # Add extra info that becomes available after handshake. |
| self._extra.update(peercert=peercert, |
| cipher=self._sock.cipher(), |
| compression=self._sock.compression(), |
| ssl_object=self._sock, |
| ) |
| |
| self._read_wants_write = False |
| self._write_wants_read = False |
| self._loop._add_reader(self._sock_fd, self._read_ready) |
| self._protocol_connected = True |
| self._loop.call_soon(self._protocol.connection_made, self) |
| # only wake up the waiter when connection_made() has been called |
| self._loop.call_soon(self._wakeup_waiter) |
| |
| if self._loop.get_debug(): |
| dt = self._loop.time() - start_time |
| logger.debug("%r: SSL handshake took %.1f ms", self, dt * 1e3) |
| |
| 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) |
| if self._loop.get_debug(): |
| logger.debug("%r pauses reading", self) |
| |
| 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) |
| if self._loop.get_debug(): |
| logger.debug("%r resumes reading", self) |
| |
| def _read_ready(self): |
| if self._conn_lost: |
| return |
| 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, 'Fatal read error on SSL transport') |
| else: |
| if data: |
| self._protocol.data_received(data) |
| else: |
| try: |
| if self._loop.get_debug(): |
| logger.debug("%r received EOF", self) |
| 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._conn_lost: |
| return |
| 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, 'Fatal write error on SSL transport') |
| 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 a bytes-like object, ' |
| 'not %r' % type(data).__name__) |
| 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, |
| waiter=None, extra=None): |
| super().__init__(loop, sock, protocol, extra) |
| self._address = address |
| self._loop.call_soon(self._protocol.connection_made, self) |
| # only start reading when connection_made() has been called |
| self._loop.call_soon(self._loop._add_reader, |
| self._sock_fd, self._read_ready) |
| if waiter is not None: |
| # only wake up the waiter when connection_made() has been called |
| self._loop.call_soon(futures._set_result_unless_cancelled, |
| waiter, None) |
| |
| def get_write_buffer_size(self): |
| return sum(len(data) for data, _ in self._buffer) |
| |
| def _read_ready(self): |
| if self._conn_lost: |
| return |
| 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, 'Fatal read error on datagram transport') |
| 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 a bytes-like object, ' |
| 'not %r' % type(data).__name__) |
| 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, |
| 'Fatal write error on datagram transport') |
| 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, |
| 'Fatal write error on datagram transport') |
| 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) |