Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 1 | """Stream-related things.""" |
| 2 | |
Guido van Rossum | 49c96fb | 2013-11-25 15:07:18 -0800 | [diff] [blame] | 3 | __all__ = ['StreamReader', 'StreamWriter', 'StreamReaderProtocol', |
Victor Stinner | 8dffc45 | 2014-01-25 15:32:06 +0100 | [diff] [blame] | 4 | 'open_connection', 'start_server', 'IncompleteReadError', |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 5 | ] |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 6 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 7 | from . import events |
| 8 | from . import futures |
| 9 | from . import protocols |
| 10 | from . import tasks |
| 11 | |
| 12 | |
| 13 | _DEFAULT_LIMIT = 2**16 |
| 14 | |
Guido van Rossum | a849be9 | 2014-01-30 16:05:28 -0800 | [diff] [blame] | 15 | |
Victor Stinner | 8dffc45 | 2014-01-25 15:32:06 +0100 | [diff] [blame] | 16 | class IncompleteReadError(EOFError): |
| 17 | """ |
| 18 | Incomplete read error. Attributes: |
| 19 | |
| 20 | - partial: read bytes string before the end of stream was reached |
| 21 | - expected: total number of expected bytes |
| 22 | """ |
| 23 | def __init__(self, partial, expected): |
| 24 | EOFError.__init__(self, "%s bytes read on a total of %s expected bytes" |
| 25 | % (len(partial), expected)) |
| 26 | self.partial = partial |
| 27 | self.expected = expected |
| 28 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 29 | |
| 30 | @tasks.coroutine |
| 31 | def open_connection(host=None, port=None, *, |
| 32 | loop=None, limit=_DEFAULT_LIMIT, **kwds): |
| 33 | """A wrapper for create_connection() returning a (reader, writer) pair. |
| 34 | |
| 35 | The reader returned is a StreamReader instance; the writer is a |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 36 | StreamWriter instance. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 37 | |
| 38 | The arguments are all the usual arguments to create_connection() |
| 39 | except protocol_factory; most common are positional host and port, |
| 40 | with various optional keyword arguments following. |
| 41 | |
| 42 | Additional optional keyword arguments are loop (to set the event loop |
| 43 | instance to use) and limit (to set the buffer limit passed to the |
| 44 | StreamReader). |
| 45 | |
| 46 | (If you want to customize the StreamReader and/or |
| 47 | StreamReaderProtocol classes, just copy the code -- there's |
| 48 | really nothing special here except some convenience.) |
| 49 | """ |
| 50 | if loop is None: |
| 51 | loop = events.get_event_loop() |
| 52 | reader = StreamReader(limit=limit, loop=loop) |
Guido van Rossum | efef9d3 | 2014-01-10 13:26:38 -0800 | [diff] [blame] | 53 | protocol = StreamReaderProtocol(reader, loop=loop) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 54 | transport, _ = yield from loop.create_connection( |
| 55 | lambda: protocol, host, port, **kwds) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 56 | writer = StreamWriter(transport, protocol, reader, loop) |
| 57 | return reader, writer |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 58 | |
| 59 | |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 60 | @tasks.coroutine |
| 61 | def start_server(client_connected_cb, host=None, port=None, *, |
| 62 | loop=None, limit=_DEFAULT_LIMIT, **kwds): |
| 63 | """Start a socket server, call back for each client connected. |
| 64 | |
| 65 | The first parameter, `client_connected_cb`, takes two parameters: |
| 66 | client_reader, client_writer. client_reader is a StreamReader |
| 67 | object, while client_writer is a StreamWriter object. This |
| 68 | parameter can either be a plain callback function or a coroutine; |
| 69 | if it is a coroutine, it will be automatically converted into a |
| 70 | Task. |
| 71 | |
| 72 | The rest of the arguments are all the usual arguments to |
| 73 | loop.create_server() except protocol_factory; most common are |
| 74 | positional host and port, with various optional keyword arguments |
| 75 | following. The return value is the same as loop.create_server(). |
| 76 | |
| 77 | Additional optional keyword arguments are loop (to set the event loop |
| 78 | instance to use) and limit (to set the buffer limit passed to the |
| 79 | StreamReader). |
| 80 | |
| 81 | The return value is the same as loop.create_server(), i.e. a |
| 82 | Server object which can be used to stop the service. |
| 83 | """ |
| 84 | if loop is None: |
| 85 | loop = events.get_event_loop() |
| 86 | |
| 87 | def factory(): |
| 88 | reader = StreamReader(limit=limit, loop=loop) |
| 89 | protocol = StreamReaderProtocol(reader, client_connected_cb, |
| 90 | loop=loop) |
| 91 | return protocol |
| 92 | |
| 93 | return (yield from loop.create_server(factory, host, port, **kwds)) |
| 94 | |
| 95 | |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame] | 96 | class FlowControlMixin(protocols.Protocol): |
| 97 | """Reusable flow control logic for StreamWriter.drain(). |
| 98 | |
| 99 | This implements the protocol methods pause_writing(), |
| 100 | resume_reading() and connection_lost(). If the subclass overrides |
| 101 | these it must call the super methods. |
| 102 | |
| 103 | StreamWriter.drain() must check for error conditions and then call |
| 104 | _make_drain_waiter(), which will return either () or a Future |
| 105 | depending on the paused state. |
| 106 | """ |
| 107 | |
| 108 | def __init__(self, loop=None): |
| 109 | self._loop = loop # May be None; we may never need it. |
| 110 | self._paused = False |
| 111 | self._drain_waiter = None |
| 112 | |
| 113 | def pause_writing(self): |
| 114 | assert not self._paused |
| 115 | self._paused = True |
| 116 | |
| 117 | def resume_writing(self): |
| 118 | assert self._paused |
| 119 | self._paused = False |
| 120 | waiter = self._drain_waiter |
| 121 | if waiter is not None: |
| 122 | self._drain_waiter = None |
| 123 | if not waiter.done(): |
| 124 | waiter.set_result(None) |
| 125 | |
| 126 | def connection_lost(self, exc): |
| 127 | # Wake up the writer if currently paused. |
| 128 | if not self._paused: |
| 129 | return |
| 130 | waiter = self._drain_waiter |
| 131 | if waiter is None: |
| 132 | return |
| 133 | self._drain_waiter = None |
| 134 | if waiter.done(): |
| 135 | return |
| 136 | if exc is None: |
| 137 | waiter.set_result(None) |
| 138 | else: |
| 139 | waiter.set_exception(exc) |
| 140 | |
| 141 | def _make_drain_waiter(self): |
| 142 | if not self._paused: |
| 143 | return () |
| 144 | waiter = self._drain_waiter |
| 145 | assert waiter is None or waiter.cancelled() |
| 146 | waiter = futures.Future(loop=self._loop) |
| 147 | self._drain_waiter = waiter |
| 148 | return waiter |
| 149 | |
| 150 | |
| 151 | class StreamReaderProtocol(FlowControlMixin, protocols.Protocol): |
| 152 | """Helper class to adapt between Protocol and StreamReader. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 153 | |
| 154 | (This is a helper class instead of making StreamReader itself a |
| 155 | Protocol subclass, because the StreamReader has other potential |
| 156 | uses, and to prevent the user of the StreamReader to accidentally |
| 157 | call inappropriate methods of the protocol.) |
| 158 | """ |
| 159 | |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 160 | def __init__(self, stream_reader, client_connected_cb=None, loop=None): |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame] | 161 | super().__init__(loop=loop) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 162 | self._stream_reader = stream_reader |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 163 | self._stream_writer = None |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 164 | self._client_connected_cb = client_connected_cb |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 165 | |
| 166 | def connection_made(self, transport): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 167 | self._stream_reader.set_transport(transport) |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 168 | if self._client_connected_cb is not None: |
| 169 | self._stream_writer = StreamWriter(transport, self, |
| 170 | self._stream_reader, |
| 171 | self._loop) |
| 172 | res = self._client_connected_cb(self._stream_reader, |
| 173 | self._stream_writer) |
| 174 | if tasks.iscoroutine(res): |
| 175 | tasks.Task(res, loop=self._loop) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 176 | |
| 177 | def connection_lost(self, exc): |
| 178 | if exc is None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 179 | self._stream_reader.feed_eof() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 180 | else: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 181 | self._stream_reader.set_exception(exc) |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame] | 182 | super().connection_lost(exc) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 183 | |
| 184 | def data_received(self, data): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 185 | self._stream_reader.feed_data(data) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 186 | |
| 187 | def eof_received(self): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 188 | self._stream_reader.feed_eof() |
| 189 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 190 | |
| 191 | class StreamWriter: |
| 192 | """Wraps a Transport. |
| 193 | |
| 194 | This exposes write(), writelines(), [can_]write_eof(), |
| 195 | get_extra_info() and close(). It adds drain() which returns an |
| 196 | optional Future on which you can wait for flow control. It also |
Guido van Rossum | efef9d3 | 2014-01-10 13:26:38 -0800 | [diff] [blame] | 197 | adds a transport property which references the Transport |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 198 | directly. |
| 199 | """ |
| 200 | |
| 201 | def __init__(self, transport, protocol, reader, loop): |
| 202 | self._transport = transport |
| 203 | self._protocol = protocol |
| 204 | self._reader = reader |
| 205 | self._loop = loop |
| 206 | |
| 207 | @property |
| 208 | def transport(self): |
| 209 | return self._transport |
| 210 | |
| 211 | def write(self, data): |
| 212 | self._transport.write(data) |
| 213 | |
| 214 | def writelines(self, data): |
| 215 | self._transport.writelines(data) |
| 216 | |
| 217 | def write_eof(self): |
| 218 | return self._transport.write_eof() |
| 219 | |
| 220 | def can_write_eof(self): |
| 221 | return self._transport.can_write_eof() |
| 222 | |
| 223 | def close(self): |
| 224 | return self._transport.close() |
| 225 | |
| 226 | def get_extra_info(self, name, default=None): |
| 227 | return self._transport.get_extra_info(name, default) |
| 228 | |
| 229 | def drain(self): |
| 230 | """This method has an unusual return value. |
| 231 | |
| 232 | The intended use is to write |
| 233 | |
| 234 | w.write(data) |
| 235 | yield from w.drain() |
| 236 | |
| 237 | When there's nothing to wait for, drain() returns (), and the |
| 238 | yield-from continues immediately. When the transport buffer |
| 239 | is full (the protocol is paused), drain() creates and returns |
| 240 | a Future and the yield-from will block until that Future is |
| 241 | completed, which will happen when the buffer is (partially) |
| 242 | drained and the protocol is resumed. |
| 243 | """ |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame] | 244 | if self._reader is not None and self._reader._exception is not None: |
Guido van Rossum | 6188bd4 | 2014-01-07 17:03:26 -0800 | [diff] [blame] | 245 | raise self._reader._exception |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 246 | if self._transport._conn_lost: # Uses private variable. |
| 247 | raise ConnectionResetError('Connection lost') |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame] | 248 | return self._protocol._make_drain_waiter() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 249 | |
| 250 | |
| 251 | class StreamReader: |
| 252 | |
| 253 | def __init__(self, limit=_DEFAULT_LIMIT, loop=None): |
| 254 | # The line length limit is a security feature; |
| 255 | # it also doubles as half the buffer limit. |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 256 | self._limit = limit |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 257 | if loop is None: |
| 258 | loop = events.get_event_loop() |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 259 | self._loop = loop |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 260 | self._buffer = bytearray() |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 261 | self._eof = False # Whether we're done. |
| 262 | self._waiter = None # A future. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 263 | self._exception = None |
| 264 | self._transport = None |
| 265 | self._paused = False |
| 266 | |
| 267 | def exception(self): |
| 268 | return self._exception |
| 269 | |
| 270 | def set_exception(self, exc): |
| 271 | self._exception = exc |
| 272 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 273 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 274 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 275 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 276 | if not waiter.cancelled(): |
| 277 | waiter.set_exception(exc) |
| 278 | |
| 279 | def set_transport(self, transport): |
| 280 | assert self._transport is None, 'Transport already set' |
| 281 | self._transport = transport |
| 282 | |
| 283 | def _maybe_resume_transport(self): |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 284 | if self._paused and len(self._buffer) <= self._limit: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 285 | self._paused = False |
Guido van Rossum | 57497ad | 2013-10-18 07:58:20 -0700 | [diff] [blame] | 286 | self._transport.resume_reading() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 287 | |
| 288 | def feed_eof(self): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 289 | self._eof = True |
| 290 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 291 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 292 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 293 | if not waiter.cancelled(): |
| 294 | waiter.set_result(True) |
| 295 | |
Yury Selivanov | f0020f5 | 2014-02-06 00:14:30 -0500 | [diff] [blame^] | 296 | def at_eof(self): |
| 297 | """Return True if the buffer is empty and 'feed_eof' was called.""" |
| 298 | return self._eof and not self._buffer |
| 299 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 300 | def feed_data(self, data): |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 301 | assert not self._eof, 'feed_data after feed_eof' |
| 302 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 303 | if not data: |
| 304 | return |
| 305 | |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 306 | self._buffer.extend(data) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 307 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 308 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 309 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 310 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 311 | if not waiter.cancelled(): |
| 312 | waiter.set_result(False) |
| 313 | |
| 314 | if (self._transport is not None and |
| 315 | not self._paused and |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 316 | len(self._buffer) > 2*self._limit): |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 317 | try: |
Guido van Rossum | 57497ad | 2013-10-18 07:58:20 -0700 | [diff] [blame] | 318 | self._transport.pause_reading() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 319 | except NotImplementedError: |
| 320 | # The transport can't be paused. |
| 321 | # We'll just have to buffer all data. |
| 322 | # Forget the transport so we don't keep trying. |
| 323 | self._transport = None |
| 324 | else: |
| 325 | self._paused = True |
| 326 | |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 327 | def _create_waiter(self, func_name): |
| 328 | # StreamReader uses a future to link the protocol feed_data() method |
| 329 | # to a read coroutine. Running two read coroutines at the same time |
| 330 | # would have an unexpected behaviour. It would not possible to know |
| 331 | # which coroutine would get the next data. |
| 332 | if self._waiter is not None: |
| 333 | raise RuntimeError('%s() called while another coroutine is ' |
| 334 | 'already waiting for incoming data' % func_name) |
| 335 | return futures.Future(loop=self._loop) |
| 336 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 337 | @tasks.coroutine |
| 338 | def readline(self): |
| 339 | if self._exception is not None: |
| 340 | raise self._exception |
| 341 | |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 342 | line = bytearray() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 343 | not_enough = True |
| 344 | |
| 345 | while not_enough: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 346 | while self._buffer and not_enough: |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 347 | ichar = self._buffer.find(b'\n') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 348 | if ichar < 0: |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 349 | line.extend(self._buffer) |
| 350 | self._buffer.clear() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 351 | else: |
| 352 | ichar += 1 |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 353 | line.extend(self._buffer[:ichar]) |
| 354 | del self._buffer[:ichar] |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 355 | not_enough = False |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 356 | |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 357 | if len(line) > self._limit: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 358 | self._maybe_resume_transport() |
| 359 | raise ValueError('Line is too long') |
| 360 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 361 | if self._eof: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 362 | break |
| 363 | |
| 364 | if not_enough: |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 365 | self._waiter = self._create_waiter('readline') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 366 | try: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 367 | yield from self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 368 | finally: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 369 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 370 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 371 | self._maybe_resume_transport() |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 372 | return bytes(line) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 373 | |
| 374 | @tasks.coroutine |
| 375 | def read(self, n=-1): |
| 376 | if self._exception is not None: |
| 377 | raise self._exception |
| 378 | |
| 379 | if not n: |
| 380 | return b'' |
| 381 | |
| 382 | if n < 0: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 383 | while not self._eof: |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 384 | self._waiter = self._create_waiter('read') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 385 | try: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 386 | yield from self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 387 | finally: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 388 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 389 | else: |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 390 | if not self._buffer and not self._eof: |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 391 | self._waiter = self._create_waiter('read') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 392 | try: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 393 | yield from self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 394 | finally: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 395 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 396 | |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 397 | if n < 0 or len(self._buffer) <= n: |
| 398 | data = bytes(self._buffer) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 399 | self._buffer.clear() |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 400 | else: |
| 401 | # n > 0 and len(self._buffer) > n |
| 402 | data = bytes(self._buffer[:n]) |
| 403 | del self._buffer[:n] |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 404 | |
Yury Selivanov | e694c97 | 2014-02-05 18:11:13 -0500 | [diff] [blame] | 405 | self._maybe_resume_transport() |
| 406 | return data |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 407 | |
| 408 | @tasks.coroutine |
| 409 | def readexactly(self, n): |
| 410 | if self._exception is not None: |
| 411 | raise self._exception |
| 412 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 413 | # There used to be "optimized" code here. It created its own |
| 414 | # Future and waited until self._buffer had at least the n |
| 415 | # bytes, then called read(n). Unfortunately, this could pause |
| 416 | # the transport if the argument was larger than the pause |
| 417 | # limit (which is twice self._limit). So now we just read() |
| 418 | # into a local buffer. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 419 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 420 | blocks = [] |
| 421 | while n > 0: |
| 422 | block = yield from self.read(n) |
| 423 | if not block: |
Victor Stinner | 8dffc45 | 2014-01-25 15:32:06 +0100 | [diff] [blame] | 424 | partial = b''.join(blocks) |
| 425 | raise IncompleteReadError(partial, len(partial) + n) |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 426 | blocks.append(block) |
| 427 | n -= len(block) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 428 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 429 | return b''.join(blocks) |