324
324
def __init__(self):
325
325
self.finished_reading = False
326
self._in_buffer_list = []
327
self._in_buffer_len = 0
327
328
self.unused_data = ''
328
329
self.bytes_left = None
329
330
self._number_needed_bytes = None
332
def _get_in_buffer(self):
333
if len(self._in_buffer_list) == 1:
334
return self._in_buffer_list[0]
335
in_buffer = ''.join(self._in_buffer_list)
336
if len(in_buffer) != self._in_buffer_len:
337
raise AssertionError(
338
"Length of buffer did not match expected value: %s != %s"
339
% self._in_buffer_len, len(in_buffer))
340
self._in_buffer_list = [in_buffer]
343
def _get_in_bytes(self, count):
344
"""Grab X bytes from the input_buffer.
346
Callers should have already checked that self._in_buffer_len is >
347
count. Note, this does not consume the bytes from the buffer. The
348
caller will still need to call _get_in_buffer() and then
349
_set_in_buffer() if they actually need to consume the bytes.
351
# check if we can yield the bytes from just the first entry in our list
352
if len(self._in_buffer_list) == 0:
353
raise AssertionError('Callers must be sure we have buffered bytes'
354
' before calling _get_in_bytes')
355
if len(self._in_buffer_list[0]) > count:
356
return self._in_buffer_list[0][:count]
357
# We can't yield it from the first buffer, so collapse all buffers, and
359
in_buf = self._get_in_buffer()
360
return in_buf[:count]
362
def _set_in_buffer(self, new_buf):
363
if new_buf is not None:
364
self._in_buffer_list = [new_buf]
365
self._in_buffer_len = len(new_buf)
367
self._in_buffer_list = []
368
self._in_buffer_len = 0
331
370
def accept_bytes(self, bytes):
332
371
"""Decode as much of bytes as possible.
338
377
data will be appended to self.unused_data.
340
379
# accept_bytes is allowed to change the state
341
current_state = self.state_accept
342
380
self._number_needed_bytes = None
343
self._in_buffer += bytes
381
# lsprof puts a very large amount of time on this specific call for
383
self._in_buffer_list.append(bytes)
384
self._in_buffer_len += len(bytes)
345
386
# Run the function for the current state.
387
current_state = self.state_accept
346
388
self.state_accept()
347
389
while current_state != self.state_accept:
348
390
# The current state has changed. Run the function for the new
379
421
# the rest of this chunk plus an END chunk.
380
422
return self.bytes_left + 4
381
423
elif self.state_accept == self._state_accept_expecting_length:
382
if self._in_buffer == '':
424
if self._in_buffer_len == 0:
383
425
# We're expecting a chunk length. There's at least two bytes
384
426
# left: a digit plus '\n'.
390
432
elif self.state_accept == self._state_accept_reading_unused:
392
434
elif self.state_accept == self._state_accept_expecting_header:
393
return max(0, len('chunked\n') - len(self._in_buffer))
435
return max(0, len('chunked\n') - self._in_buffer_len)
395
437
raise AssertionError("Impossible state: %r" % (self.state_accept,))
403
445
def _extract_line(self):
404
pos = self._in_buffer.find('\n')
446
in_buf = self._get_in_buffer()
447
pos = in_buf.find('\n')
406
449
# We haven't read a complete line yet, so request more bytes before
408
451
raise _NeedMoreBytes(1)
409
line = self._in_buffer[:pos]
410
453
# Trim the prefix (including '\n' delimiter) from the _in_buffer.
411
self._in_buffer = self._in_buffer[pos+1:]
454
self._set_in_buffer(in_buf[pos+1:])
414
457
def _finished(self):
415
self.unused_data = self._in_buffer
458
self.unused_data = self._get_in_buffer()
459
# self._in_buffer = None
460
self._in_buffer_list = []
461
self._in_buffer_len = 0
417
462
self.state_accept = self._state_accept_reading_unused
419
464
error_args = tuple(self.error_in_progress)
448
493
self.state_accept = self._state_accept_reading_chunk
450
495
def _state_accept_reading_chunk(self):
451
in_buffer_len = len(self._in_buffer)
452
self.chunk_in_progress += self._in_buffer[:self.bytes_left]
453
self._in_buffer = self._in_buffer[self.bytes_left:]
496
in_buf = self._get_in_buffer()
497
in_buffer_len = len(in_buf)
498
self.chunk_in_progress += in_buf[:self.bytes_left]
499
self._set_in_buffer(in_buf[self.bytes_left:])
454
500
self.bytes_left -= in_buffer_len
455
501
if self.bytes_left <= 0:
456
502
# Finished with chunk
463
509
self.state_accept = self._state_accept_expecting_length
465
511
def _state_accept_reading_unused(self):
466
self.unused_data += self._in_buffer
512
self.unused_data += self._get_in_buffer()
513
self._in_buffer_list = []
470
516
class LengthPrefixedBodyDecoder(_StatefulDecoder):
498
544
return self.state_read()
500
546
def _state_accept_expecting_length(self):
501
pos = self._in_buffer.find('\n')
547
in_buf = self._get_in_buffer()
548
pos = in_buf.find('\n')
504
self.bytes_left = int(self._in_buffer[:pos])
505
self._in_buffer = self._in_buffer[pos+1:]
551
self.bytes_left = int(in_buf[:pos])
552
self._set_in_buffer(in_buf[pos+1:])
506
553
self.state_accept = self._state_accept_reading_body
507
554
self.state_read = self._state_read_body_buffer
509
556
def _state_accept_reading_body(self):
510
self._body += self._in_buffer
511
self.bytes_left -= len(self._in_buffer)
557
in_buf = self._get_in_buffer()
559
self.bytes_left -= len(in_buf)
560
self._set_in_buffer(None)
513
561
if self.bytes_left <= 0:
514
562
# Finished with body
515
563
if self.bytes_left != 0:
519
567
self.state_accept = self._state_accept_reading_trailer
521
569
def _state_accept_reading_trailer(self):
522
self._trailer_buffer += self._in_buffer
570
self._trailer_buffer += self._get_in_buffer()
571
self._set_in_buffer(None)
524
572
# TODO: what if the trailer does not match "done\n"? Should this raise
525
573
# a ProtocolViolation exception?
526
574
if self._trailer_buffer.startswith('done\n'):
529
577
self.finished_reading = True
531
579
def _state_accept_reading_unused(self):
532
self.unused_data += self._in_buffer
580
self.unused_data += self._get_in_buffer()
581
self._set_in_buffer(None)
535
583
def _state_read_no_data(self):
865
913
self.message_handler.protocol_error(exception)
867
915
def _extract_length_prefixed_bytes(self):
868
if len(self._in_buffer) < 4:
916
if self._in_buffer_len < 4:
869
917
# A length prefix by itself is 4 bytes, and we don't even have that
871
919
raise _NeedMoreBytes(4)
872
(length,) = struct.unpack('!L', self._in_buffer[:4])
920
(length,) = struct.unpack('!L', self._get_in_bytes(4))
873
921
end_of_bytes = 4 + length
874
if len(self._in_buffer) < end_of_bytes:
922
if self._in_buffer_len < end_of_bytes:
875
923
# We haven't yet read as many bytes as the length-prefix says there
877
925
raise _NeedMoreBytes(end_of_bytes)
878
926
# Extract the bytes from the buffer.
879
bytes = self._in_buffer[4:end_of_bytes]
880
self._in_buffer = self._in_buffer[end_of_bytes:]
927
in_buf = self._get_in_buffer()
928
bytes = in_buf[4:end_of_bytes]
929
self._set_in_buffer(in_buf[end_of_bytes:])
883
932
def _extract_prefixed_bencoded_data(self):
892
941
def _extract_single_byte(self):
893
if self._in_buffer == '':
942
if self._in_buffer_len == 0:
894
943
# The buffer is empty
895
944
raise _NeedMoreBytes(1)
896
one_byte = self._in_buffer[0]
897
self._in_buffer = self._in_buffer[1:]
945
in_buf = self._get_in_buffer()
947
self._set_in_buffer(in_buf[1:])
900
950
def _state_accept_expecting_protocol_version(self):
901
needed_bytes = len(MESSAGE_VERSION_THREE) - len(self._in_buffer)
951
needed_bytes = len(MESSAGE_VERSION_THREE) - self._in_buffer_len
952
in_buf = self._get_in_buffer()
902
953
if needed_bytes > 0:
903
954
# We don't have enough bytes to check if the protocol version
904
955
# marker is right. But we can check if it is already wrong by
908
959
# len(MESSAGE_VERSION_THREE) bytes. So if the bytes we have so far
909
960
# are wrong then we should just raise immediately rather than
911
if not MESSAGE_VERSION_THREE.startswith(self._in_buffer):
962
if not MESSAGE_VERSION_THREE.startswith(in_buf):
912
963
# We have enough bytes to know the protocol version is wrong
913
raise errors.UnexpectedProtocolVersionMarker(self._in_buffer)
964
raise errors.UnexpectedProtocolVersionMarker(in_buf)
914
965
raise _NeedMoreBytes(len(MESSAGE_VERSION_THREE))
915
if not self._in_buffer.startswith(MESSAGE_VERSION_THREE):
916
raise errors.UnexpectedProtocolVersionMarker(self._in_buffer)
917
self._in_buffer = self._in_buffer[len(MESSAGE_VERSION_THREE):]
966
if not in_buf.startswith(MESSAGE_VERSION_THREE):
967
raise errors.UnexpectedProtocolVersionMarker(in_buf)
968
self._set_in_buffer(in_buf[len(MESSAGE_VERSION_THREE):])
918
969
self.state_accept = self._state_accept_expecting_headers
920
971
def _state_accept_expecting_headers(self):
969
1020
raise errors.SmartMessageHandlerError(sys.exc_info())
972
self.unused_data = self._in_buffer
1023
self.unused_data = self._get_in_buffer()
1024
self._set_in_buffer(None)
974
1025
self.state_accept = self._state_accept_reading_unused
976
1027
self.message_handler.end_received()
978
1029
raise errors.SmartMessageHandlerError(sys.exc_info())
980
1031
def _state_accept_reading_unused(self):
981
self.unused_data += self._in_buffer
1032
self.unused_data = self._get_in_buffer()
1033
self._set_in_buffer(None)
984
1035
def next_read_size(self):
985
1036
if self.state_accept == self._state_accept_reading_unused:
994
1045
if self._number_needed_bytes is not None:
995
return self._number_needed_bytes - len(self._in_buffer)
1046
return self._number_needed_bytes - self._in_buffer_len
997
1048
raise AssertionError("don't know how many bytes are expected!")