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 | |
| 7 | import collections |
| 8 | |
| 9 | from . import events |
| 10 | from . import futures |
| 11 | from . import protocols |
| 12 | from . import tasks |
| 13 | |
| 14 | |
| 15 | _DEFAULT_LIMIT = 2**16 |
| 16 | |
Victor Stinner | 8dffc45 | 2014-01-25 15:32:06 +0100 | [diff] [blame] | 17 | class IncompleteReadError(EOFError): |
| 18 | """ |
| 19 | Incomplete read error. Attributes: |
| 20 | |
| 21 | - partial: read bytes string before the end of stream was reached |
| 22 | - expected: total number of expected bytes |
| 23 | """ |
| 24 | def __init__(self, partial, expected): |
| 25 | EOFError.__init__(self, "%s bytes read on a total of %s expected bytes" |
| 26 | % (len(partial), expected)) |
| 27 | self.partial = partial |
| 28 | self.expected = expected |
| 29 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 30 | |
| 31 | @tasks.coroutine |
| 32 | def open_connection(host=None, port=None, *, |
| 33 | loop=None, limit=_DEFAULT_LIMIT, **kwds): |
| 34 | """A wrapper for create_connection() returning a (reader, writer) pair. |
| 35 | |
| 36 | The reader returned is a StreamReader instance; the writer is a |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 37 | StreamWriter instance. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 38 | |
| 39 | The arguments are all the usual arguments to create_connection() |
| 40 | except protocol_factory; most common are positional host and port, |
| 41 | with various optional keyword arguments following. |
| 42 | |
| 43 | Additional optional keyword arguments are loop (to set the event loop |
| 44 | instance to use) and limit (to set the buffer limit passed to the |
| 45 | StreamReader). |
| 46 | |
| 47 | (If you want to customize the StreamReader and/or |
| 48 | StreamReaderProtocol classes, just copy the code -- there's |
| 49 | really nothing special here except some convenience.) |
| 50 | """ |
| 51 | if loop is None: |
| 52 | loop = events.get_event_loop() |
| 53 | reader = StreamReader(limit=limit, loop=loop) |
Guido van Rossum | efef9d3 | 2014-01-10 13:26:38 -0800 | [diff] [blame] | 54 | protocol = StreamReaderProtocol(reader, loop=loop) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 55 | transport, _ = yield from loop.create_connection( |
| 56 | lambda: protocol, host, port, **kwds) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 57 | writer = StreamWriter(transport, protocol, reader, loop) |
| 58 | return reader, writer |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 59 | |
| 60 | |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 61 | @tasks.coroutine |
| 62 | def start_server(client_connected_cb, host=None, port=None, *, |
| 63 | loop=None, limit=_DEFAULT_LIMIT, **kwds): |
| 64 | """Start a socket server, call back for each client connected. |
| 65 | |
| 66 | The first parameter, `client_connected_cb`, takes two parameters: |
| 67 | client_reader, client_writer. client_reader is a StreamReader |
| 68 | object, while client_writer is a StreamWriter object. This |
| 69 | parameter can either be a plain callback function or a coroutine; |
| 70 | if it is a coroutine, it will be automatically converted into a |
| 71 | Task. |
| 72 | |
| 73 | The rest of the arguments are all the usual arguments to |
| 74 | loop.create_server() except protocol_factory; most common are |
| 75 | positional host and port, with various optional keyword arguments |
| 76 | following. The return value is the same as loop.create_server(). |
| 77 | |
| 78 | Additional optional keyword arguments are loop (to set the event loop |
| 79 | instance to use) and limit (to set the buffer limit passed to the |
| 80 | StreamReader). |
| 81 | |
| 82 | The return value is the same as loop.create_server(), i.e. a |
| 83 | Server object which can be used to stop the service. |
| 84 | """ |
| 85 | if loop is None: |
| 86 | loop = events.get_event_loop() |
| 87 | |
| 88 | def factory(): |
| 89 | reader = StreamReader(limit=limit, loop=loop) |
| 90 | protocol = StreamReaderProtocol(reader, client_connected_cb, |
| 91 | loop=loop) |
| 92 | return protocol |
| 93 | |
| 94 | return (yield from loop.create_server(factory, host, port, **kwds)) |
| 95 | |
| 96 | |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame^] | 97 | class FlowControlMixin(protocols.Protocol): |
| 98 | """Reusable flow control logic for StreamWriter.drain(). |
| 99 | |
| 100 | This implements the protocol methods pause_writing(), |
| 101 | resume_reading() and connection_lost(). If the subclass overrides |
| 102 | these it must call the super methods. |
| 103 | |
| 104 | StreamWriter.drain() must check for error conditions and then call |
| 105 | _make_drain_waiter(), which will return either () or a Future |
| 106 | depending on the paused state. |
| 107 | """ |
| 108 | |
| 109 | def __init__(self, loop=None): |
| 110 | self._loop = loop # May be None; we may never need it. |
| 111 | self._paused = False |
| 112 | self._drain_waiter = None |
| 113 | |
| 114 | def pause_writing(self): |
| 115 | assert not self._paused |
| 116 | self._paused = True |
| 117 | |
| 118 | def resume_writing(self): |
| 119 | assert self._paused |
| 120 | self._paused = False |
| 121 | waiter = self._drain_waiter |
| 122 | if waiter is not None: |
| 123 | self._drain_waiter = None |
| 124 | if not waiter.done(): |
| 125 | waiter.set_result(None) |
| 126 | |
| 127 | def connection_lost(self, exc): |
| 128 | # Wake up the writer if currently paused. |
| 129 | if not self._paused: |
| 130 | return |
| 131 | waiter = self._drain_waiter |
| 132 | if waiter is None: |
| 133 | return |
| 134 | self._drain_waiter = None |
| 135 | if waiter.done(): |
| 136 | return |
| 137 | if exc is None: |
| 138 | waiter.set_result(None) |
| 139 | else: |
| 140 | waiter.set_exception(exc) |
| 141 | |
| 142 | def _make_drain_waiter(self): |
| 143 | if not self._paused: |
| 144 | return () |
| 145 | waiter = self._drain_waiter |
| 146 | assert waiter is None or waiter.cancelled() |
| 147 | waiter = futures.Future(loop=self._loop) |
| 148 | self._drain_waiter = waiter |
| 149 | return waiter |
| 150 | |
| 151 | |
| 152 | class StreamReaderProtocol(FlowControlMixin, protocols.Protocol): |
| 153 | """Helper class to adapt between Protocol and StreamReader. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 154 | |
| 155 | (This is a helper class instead of making StreamReader itself a |
| 156 | Protocol subclass, because the StreamReader has other potential |
| 157 | uses, and to prevent the user of the StreamReader to accidentally |
| 158 | call inappropriate methods of the protocol.) |
| 159 | """ |
| 160 | |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 161 | def __init__(self, stream_reader, client_connected_cb=None, loop=None): |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame^] | 162 | super().__init__(loop=loop) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 163 | self._stream_reader = stream_reader |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 164 | self._stream_writer = None |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 165 | self._client_connected_cb = client_connected_cb |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 166 | |
| 167 | def connection_made(self, transport): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 168 | self._stream_reader.set_transport(transport) |
Guido van Rossum | 1540b16 | 2013-11-19 11:43:38 -0800 | [diff] [blame] | 169 | if self._client_connected_cb is not None: |
| 170 | self._stream_writer = StreamWriter(transport, self, |
| 171 | self._stream_reader, |
| 172 | self._loop) |
| 173 | res = self._client_connected_cb(self._stream_reader, |
| 174 | self._stream_writer) |
| 175 | if tasks.iscoroutine(res): |
| 176 | tasks.Task(res, loop=self._loop) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 177 | |
| 178 | def connection_lost(self, exc): |
| 179 | if exc is None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 180 | self._stream_reader.feed_eof() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 181 | else: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 182 | self._stream_reader.set_exception(exc) |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame^] | 183 | super().connection_lost(exc) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 184 | |
| 185 | def data_received(self, data): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 186 | self._stream_reader.feed_data(data) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 187 | |
| 188 | def eof_received(self): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 189 | self._stream_reader.feed_eof() |
| 190 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 191 | |
| 192 | class StreamWriter: |
| 193 | """Wraps a Transport. |
| 194 | |
| 195 | This exposes write(), writelines(), [can_]write_eof(), |
| 196 | get_extra_info() and close(). It adds drain() which returns an |
| 197 | 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] | 198 | adds a transport property which references the Transport |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 199 | directly. |
| 200 | """ |
| 201 | |
| 202 | def __init__(self, transport, protocol, reader, loop): |
| 203 | self._transport = transport |
| 204 | self._protocol = protocol |
| 205 | self._reader = reader |
| 206 | self._loop = loop |
| 207 | |
| 208 | @property |
| 209 | def transport(self): |
| 210 | return self._transport |
| 211 | |
| 212 | def write(self, data): |
| 213 | self._transport.write(data) |
| 214 | |
| 215 | def writelines(self, data): |
| 216 | self._transport.writelines(data) |
| 217 | |
| 218 | def write_eof(self): |
| 219 | return self._transport.write_eof() |
| 220 | |
| 221 | def can_write_eof(self): |
| 222 | return self._transport.can_write_eof() |
| 223 | |
| 224 | def close(self): |
| 225 | return self._transport.close() |
| 226 | |
| 227 | def get_extra_info(self, name, default=None): |
| 228 | return self._transport.get_extra_info(name, default) |
| 229 | |
| 230 | def drain(self): |
| 231 | """This method has an unusual return value. |
| 232 | |
| 233 | The intended use is to write |
| 234 | |
| 235 | w.write(data) |
| 236 | yield from w.drain() |
| 237 | |
| 238 | When there's nothing to wait for, drain() returns (), and the |
| 239 | yield-from continues immediately. When the transport buffer |
| 240 | is full (the protocol is paused), drain() creates and returns |
| 241 | a Future and the yield-from will block until that Future is |
| 242 | completed, which will happen when the buffer is (partially) |
| 243 | drained and the protocol is resumed. |
| 244 | """ |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame^] | 245 | 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] | 246 | raise self._reader._exception |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 247 | if self._transport._conn_lost: # Uses private variable. |
| 248 | raise ConnectionResetError('Connection lost') |
Guido van Rossum | 4d62d0b | 2014-01-29 14:24:45 -0800 | [diff] [blame^] | 249 | return self._protocol._make_drain_waiter() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 250 | |
| 251 | |
| 252 | class StreamReader: |
| 253 | |
| 254 | def __init__(self, limit=_DEFAULT_LIMIT, loop=None): |
| 255 | # The line length limit is a security feature; |
| 256 | # it also doubles as half the buffer limit. |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 257 | self._limit = limit |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 258 | if loop is None: |
| 259 | loop = events.get_event_loop() |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 260 | self._loop = loop |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 261 | # TODO: Use a bytearray for a buffer, like the transport. |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 262 | self._buffer = collections.deque() # Deque of bytes objects. |
| 263 | self._byte_count = 0 # Bytes in buffer. |
| 264 | self._eof = False # Whether we're done. |
| 265 | self._waiter = None # A future. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 266 | self._exception = None |
| 267 | self._transport = None |
| 268 | self._paused = False |
| 269 | |
| 270 | def exception(self): |
| 271 | return self._exception |
| 272 | |
| 273 | def set_exception(self, exc): |
| 274 | self._exception = exc |
| 275 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 276 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 277 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 278 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 279 | if not waiter.cancelled(): |
| 280 | waiter.set_exception(exc) |
| 281 | |
| 282 | def set_transport(self, transport): |
| 283 | assert self._transport is None, 'Transport already set' |
| 284 | self._transport = transport |
| 285 | |
| 286 | def _maybe_resume_transport(self): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 287 | if self._paused and self._byte_count <= self._limit: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 288 | self._paused = False |
Guido van Rossum | 57497ad | 2013-10-18 07:58:20 -0700 | [diff] [blame] | 289 | self._transport.resume_reading() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 290 | |
| 291 | def feed_eof(self): |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 292 | self._eof = True |
| 293 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 294 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 295 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 296 | if not waiter.cancelled(): |
| 297 | waiter.set_result(True) |
| 298 | |
| 299 | def feed_data(self, data): |
| 300 | if not data: |
| 301 | return |
| 302 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 303 | self._buffer.append(data) |
| 304 | self._byte_count += len(data) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 305 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 306 | waiter = self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 307 | if waiter is not None: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 308 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 309 | if not waiter.cancelled(): |
| 310 | waiter.set_result(False) |
| 311 | |
| 312 | if (self._transport is not None and |
| 313 | not self._paused and |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 314 | self._byte_count > 2*self._limit): |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 315 | try: |
Guido van Rossum | 57497ad | 2013-10-18 07:58:20 -0700 | [diff] [blame] | 316 | self._transport.pause_reading() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 317 | except NotImplementedError: |
| 318 | # The transport can't be paused. |
| 319 | # We'll just have to buffer all data. |
| 320 | # Forget the transport so we don't keep trying. |
| 321 | self._transport = None |
| 322 | else: |
| 323 | self._paused = True |
| 324 | |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 325 | def _create_waiter(self, func_name): |
| 326 | # StreamReader uses a future to link the protocol feed_data() method |
| 327 | # to a read coroutine. Running two read coroutines at the same time |
| 328 | # would have an unexpected behaviour. It would not possible to know |
| 329 | # which coroutine would get the next data. |
| 330 | if self._waiter is not None: |
| 331 | raise RuntimeError('%s() called while another coroutine is ' |
| 332 | 'already waiting for incoming data' % func_name) |
| 333 | return futures.Future(loop=self._loop) |
| 334 | |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 335 | @tasks.coroutine |
| 336 | def readline(self): |
| 337 | if self._exception is not None: |
| 338 | raise self._exception |
| 339 | |
| 340 | parts = [] |
| 341 | parts_size = 0 |
| 342 | not_enough = True |
| 343 | |
| 344 | while not_enough: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 345 | while self._buffer and not_enough: |
| 346 | data = self._buffer.popleft() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 347 | ichar = data.find(b'\n') |
| 348 | if ichar < 0: |
| 349 | parts.append(data) |
| 350 | parts_size += len(data) |
| 351 | else: |
| 352 | ichar += 1 |
| 353 | head, tail = data[:ichar], data[ichar:] |
| 354 | if tail: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 355 | self._buffer.appendleft(tail) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 356 | not_enough = False |
| 357 | parts.append(head) |
| 358 | parts_size += len(head) |
| 359 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 360 | if parts_size > self._limit: |
| 361 | self._byte_count -= parts_size |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 362 | self._maybe_resume_transport() |
| 363 | raise ValueError('Line is too long') |
| 364 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 365 | if self._eof: |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 366 | break |
| 367 | |
| 368 | if not_enough: |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 369 | self._waiter = self._create_waiter('readline') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 370 | try: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 371 | yield from self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 372 | finally: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 373 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 374 | |
| 375 | line = b''.join(parts) |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 376 | self._byte_count -= parts_size |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 377 | self._maybe_resume_transport() |
| 378 | |
| 379 | return line |
| 380 | |
| 381 | @tasks.coroutine |
| 382 | def read(self, n=-1): |
| 383 | if self._exception is not None: |
| 384 | raise self._exception |
| 385 | |
| 386 | if not n: |
| 387 | return b'' |
| 388 | |
| 389 | if n < 0: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 390 | while 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 | else: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 397 | if not self._byte_count and not self._eof: |
Victor Stinner | 183e347 | 2014-01-23 17:40:03 +0100 | [diff] [blame] | 398 | self._waiter = self._create_waiter('read') |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 399 | try: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 400 | yield from self._waiter |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 401 | finally: |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 402 | self._waiter = None |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 403 | |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 404 | if n < 0 or self._byte_count <= n: |
| 405 | data = b''.join(self._buffer) |
| 406 | self._buffer.clear() |
| 407 | self._byte_count = 0 |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 408 | self._maybe_resume_transport() |
| 409 | return data |
| 410 | |
| 411 | parts = [] |
| 412 | parts_bytes = 0 |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 413 | while self._buffer and parts_bytes < n: |
| 414 | data = self._buffer.popleft() |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 415 | data_bytes = len(data) |
| 416 | if n < parts_bytes + data_bytes: |
| 417 | data_bytes = n - parts_bytes |
| 418 | data, rest = data[:data_bytes], data[data_bytes:] |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 419 | self._buffer.appendleft(rest) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 420 | |
| 421 | parts.append(data) |
| 422 | parts_bytes += data_bytes |
Guido van Rossum | 355491d | 2013-10-18 15:17:11 -0700 | [diff] [blame] | 423 | self._byte_count -= data_bytes |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 424 | self._maybe_resume_transport() |
| 425 | |
| 426 | return b''.join(parts) |
| 427 | |
| 428 | @tasks.coroutine |
| 429 | def readexactly(self, n): |
| 430 | if self._exception is not None: |
| 431 | raise self._exception |
| 432 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 433 | # There used to be "optimized" code here. It created its own |
| 434 | # Future and waited until self._buffer had at least the n |
| 435 | # bytes, then called read(n). Unfortunately, this could pause |
| 436 | # the transport if the argument was larger than the pause |
| 437 | # limit (which is twice self._limit). So now we just read() |
| 438 | # into a local buffer. |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 439 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 440 | blocks = [] |
| 441 | while n > 0: |
| 442 | block = yield from self.read(n) |
| 443 | if not block: |
Victor Stinner | 8dffc45 | 2014-01-25 15:32:06 +0100 | [diff] [blame] | 444 | partial = b''.join(blocks) |
| 445 | raise IncompleteReadError(partial, len(partial) + n) |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 446 | blocks.append(block) |
| 447 | n -= len(block) |
Guido van Rossum | 27b7c7e | 2013-10-17 13:40:50 -0700 | [diff] [blame] | 448 | |
Guido van Rossum | 3845521 | 2014-01-06 16:09:18 -0800 | [diff] [blame] | 449 | return b''.join(blocks) |