1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
Lib/httplib.py
r"""HTTP/1.1 client library

<intro stuff goes here>
<other stuff, too>

HTTPConnection goes through a number of "states", which define when a client
may legally make another request or fetch the response for a particular
request. This diagram details these state transitions:

    (null)
      |
      | HTTPConnection()
      v
    Idle
      |
      | putrequest()
      v
    Request-started
      |
      | ( putheader() )*  endheaders()
      v
    Request-sent
      |
      | response = getresponse()
      v
    Unread-response   [Response-headers-read]
      |\____________________
      |                     |
      | response.read()     | putrequest()
      v                     v
    Idle                  Req-started-unread-response
                     ______/|
                   /        |
   response.read() |        | ( putheader() )*  endheaders()
                   v        v
       Request-started    Req-sent-unread-response
                            |
                            | response.read()
                            v
                          Request-sent

This diagram presents the following rules:
  -- a second request may not be started until {response-headers-read}
  -- a response [object] cannot be retrieved until {request-sent}
  -- there is no differentiation between an unread response body and a
     partially read response body

Note: this enforcement is applied by the HTTPConnection class. The
      HTTPResponse class does not enforce this state machine, which
      implies sophisticated clients may accelerate the request/response
      pipeline. Caution should be taken, though: accelerating the states
      beyond the above pattern may imply knowledge of the server's
      connection-close behavior for certain requests. For example, it
      is impossible to tell whether the server will close the connection
      UNTIL the response headers have been read; this means that further
      requests cannot be placed into the pipeline until it is known that
      the server will NOT be closing the connection.

Logical State                  __state            __response
-------------                  -------            ----------
Idle                           _CS_IDLE           None
Request-started                _CS_REQ_STARTED    None
Request-sent                   _CS_REQ_SENT       None
Unread-response                _CS_IDLE           <response_class>
Req-started-unread-response    _CS_REQ_STARTED    <response_class>
Req-sent-unread-response       _CS_REQ_SENT       <response_class>
"""

from array import array
import os
import re
import socket
from sys import py3kwarning
from urlparse import urlsplit
import warnings
with warnings.catch_warnings():
    if py3kwarning:
        warnings.filterwarnings("ignore", ".*mimetools has been removed",
                                DeprecationWarning)
    import mimetools

try:
    from cStringIO import StringIO
except ImportError:
    from StringIO import StringIO

__all__ = ["HTTP", "HTTPResponse", "HTTPConnection",
           "HTTPException", "NotConnected", "UnknownProtocol",
           "UnknownTransferEncoding", "UnimplementedFileMode",
           "IncompleteRead", "InvalidURL", "ImproperConnectionState",
           "CannotSendRequest", "CannotSendHeader", "ResponseNotReady",
           "BadStatusLine", "error", "responses"]

HTTP_PORT = 80
HTTPS_PORT = 443

_UNKNOWN = 'UNKNOWN'

# connection states
_CS_IDLE = 'Idle'
_CS_REQ_STARTED = 'Request-started'
_CS_REQ_SENT = 'Request-sent'

# status codes
# informational
CONTINUE = 100
SWITCHING_PROTOCOLS = 101
PROCESSING = 102

# successful
OK = 200
CREATED = 201
ACCEPTED = 202
NON_AUTHORITATIVE_INFORMATION = 203
NO_CONTENT = 204
RESET_CONTENT = 205
PARTIAL_CONTENT = 206
MULTI_STATUS = 207
IM_USED = 226

# redirection
MULTIPLE_CHOICES = 300
MOVED_PERMANENTLY = 301
FOUND = 302
SEE_OTHER = 303
NOT_MODIFIED = 304
USE_PROXY = 305
TEMPORARY_REDIRECT = 307

# client error
BAD_REQUEST = 400
UNAUTHORIZED = 401
PAYMENT_REQUIRED = 402
FORBIDDEN = 403
NOT_FOUND = 404
METHOD_NOT_ALLOWED = 405
NOT_ACCEPTABLE = 406
PROXY_AUTHENTICATION_REQUIRED = 407
REQUEST_TIMEOUT = 408
CONFLICT = 409
GONE = 410
LENGTH_REQUIRED = 411
PRECONDITION_FAILED = 412
REQUEST_ENTITY_TOO_LARGE = 413
REQUEST_URI_TOO_LONG = 414
UNSUPPORTED_MEDIA_TYPE = 415
REQUESTED_RANGE_NOT_SATISFIABLE = 416
EXPECTATION_FAILED = 417
UNPROCESSABLE_ENTITY = 422
LOCKED = 423
FAILED_DEPENDENCY = 424
UPGRADE_REQUIRED = 426

# server error
INTERNAL_SERVER_ERROR = 500
NOT_IMPLEMENTED = 501
BAD_GATEWAY = 502
SERVICE_UNAVAILABLE = 503
GATEWAY_TIMEOUT = 504
HTTP_VERSION_NOT_SUPPORTED = 505
INSUFFICIENT_STORAGE = 507
NOT_EXTENDED = 510

# Mapping status codes to official W3C names
responses = {
    100: 'Continue',
    101: 'Switching Protocols',

    200: 'OK',
    201: 'Created',
    202: 'Accepted',
    203: 'Non-Authoritative Information',
    204: 'No Content',
    205: 'Reset Content',
    206: 'Partial Content',

    300: 'Multiple Choices',
    301: 'Moved Permanently',
    302: 'Found',
    303: 'See Other',
    304: 'Not Modified',
    305: 'Use Proxy',
    306: '(Unused)',
    307: 'Temporary Redirect',

    400: 'Bad Request',
    401: 'Unauthorized',
    402: 'Payment Required',
    403: 'Forbidden',
    404: 'Not Found',
    405: 'Method Not Allowed',
    406: 'Not Acceptable',
    407: 'Proxy Authentication Required',
    408: 'Request Timeout',
    409: 'Conflict',
    410: 'Gone',
    411: 'Length Required',
    412: 'Precondition Failed',
    413: 'Request Entity Too Large',
    414: 'Request-URI Too Long',
    415: 'Unsupported Media Type',
    416: 'Requested Range Not Satisfiable',
    417: 'Expectation Failed',

    500: 'Internal Server Error',
    501: 'Not Implemented',
    502: 'Bad Gateway',
    503: 'Service Unavailable',
    504: 'Gateway Timeout',
    505: 'HTTP Version Not Supported',
}

# maximal amount of data to read at one time in _safe_read
MAXAMOUNT = 1048576

# maximal line length when calling readline().
_MAXLINE = 65536

# maximum amount of headers accepted
_MAXHEADERS = 100

# Header name/value ABNF (http://tools.ietf.org/html/rfc7230#section-3.2)
#
# VCHAR          = %x21-7E
# obs-text       = %x80-FF
# header-field   = field-name ":" OWS field-value OWS
# field-name     = token
# field-value    = *( field-content / obs-fold )
# field-content  = field-vchar [ 1*( SP / HTAB ) field-vchar ]
# field-vchar    = VCHAR / obs-text
#
# obs-fold       = CRLF 1*( SP / HTAB )
#                ; obsolete line folding
#                ; see Section 3.2.4

# token          = 1*tchar
#
# tchar          = "!" / "#" / "$" / "%" / "&" / "'" / "*"
#                / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~"
#                / DIGIT / ALPHA
#                ; any VCHAR, except delimiters
#
# VCHAR defined in http://tools.ietf.org/html/rfc5234#appendix-B.1

# the patterns for both name and value are more leniant than RFC
# definitions to allow for backwards compatibility
_is_legal_header_name = re.compile(r'\A[^:\s][^:\r\n]*\Z').match
_is_illegal_header_value = re.compile(r'\n(?![ \t])|\r(?![ \t\n])').search

# We always set the Content-Length header for these methods because some
# servers will otherwise respond with a 411
_METHODS_EXPECTING_BODY = {'PATCH', 'POST', 'PUT'}


class HTTPMessage(mimetools.Message):

    def addheader(self, key, value):
        """Add header for field key handling repeats."""
        prev = self.dict.get(key)
        if prev is None:
            self.dict[key] = value
        else:
            combined = ", ".join((prev, value))
            self.dict[key] = combined

    def addcontinue(self, key, more):
        """Add more field data from a continuation line."""
        prev = self.dict[key]
        self.dict[key] = prev + "\n " + more

    def readheaders(self):
        """Read header lines.

        Read header lines up to the entirely blank line that terminates them.
        The (normally blank) line that ends the headers is skipped, but not
        included in the returned list.  If a non-header line ends the headers,
        (which is an error), an attempt is made to backspace over it; it is
        never included in the returned list.

        The variable self.status is set to the empty string if all went well,
        otherwise it is an error message.  The variable self.headers is a
        completely uninterpreted list of lines contained in the header (so
        printing them will reproduce the header exactly as it appears in the
        file).

        If multiple header fields with the same name occur, they are combined
        according to the rules in RFC 2616 sec 4.2:

        Appending each subsequent field-value to the first, each separated
        by a comma. The order in which header fields with the same field-name
        are received is significant to the interpretation of the combined
        field value.
        """
        # XXX The implementation overrides the readheaders() method of
        # rfc822.Message.  The base class design isn't amenable to
        # customized behavior here so the method here is a copy of the
        # base class code with a few small changes.

        self.dict = {}
        self.unixfrom = ''
        self.headers = hlist = []
        self.status = ''
        headerseen = ""
        firstline = 1
        startofline = unread = tell = None
        if hasattr(self.fp, 'unread'):
            unread = self.fp.unread
        elif self.seekable:
            tell = self.fp.tell
        while True:
            if len(hlist) > _MAXHEADERS:
                raise HTTPException("got more than %d headers" % _MAXHEADERS)
            if tell:
                try:
                    startofline = tell()
                except IOError:
                    startofline = tell = None
                    self.seekable = 0
            line = self.fp.readline(_MAXLINE + 1)
            if len(line) > _MAXLINE:
                raise LineTooLong("header line")
            if not line:
                self.status = 'EOF in headers'
                break
            # Skip unix From name time lines
            if firstline and line.startswith('From '):
                self.unixfrom = self.unixfrom + line
                continue
            firstline = 0
            if headerseen and line[0] in ' \t':
                # XXX Not sure if continuation lines are handled properly
                # for http and/or for repeating headers
                # It's a continuation line.
                hlist.append(line)
                self.addcontinue(headerseen, line.strip())
                continue
            elif self.iscomment(line):
                # It's a comment.  Ignore it.
                continue
            elif self.islast(line):
                # Note! No pushback here!  The delimiter line gets eaten.
                break
            headerseen = self.isheader(line)
            if headerseen:
                # It's a legal header line, save it.
                hlist.append(line)
                self.addheader(headerseen, line[len(headerseen)+1:].strip())
                continue
            elif headerseen is not None:
                # An empty header name. These aren't allowed in HTTP, but it's
                # probably a benign mistake. Don't add the header, just keep
                # going.
                continue
            else:
                # It's not a header line; throw it back and stop here.
                if not self.dict:
                    self.status = 'No headers'
                else:
                    self.status = 'Non-header line where header expected'
                # Try to undo the read.
                if unread:
                    unread(line)
                elif tell:
                    self.fp.seek(startofline)
                else:
                    self.status = self.status + '; bad seek'
                break

class HTTPResponse:

    # strict: If true, raise BadStatusLine if the status line can't be
    # parsed as a valid HTTP/1.0 or 1.1 status line.  By default it is
    # false because it prevents clients from talking to HTTP/0.9
    # servers.  Note that a response with a sufficiently corrupted
    # status line will look like an HTTP/0.9 response.

    # See RFC 2616 sec 19.6 and RFC 1945 sec 6 for details.

    def __init__(self, sock, debuglevel=0, strict=0, method=None, buffering=False):
        if buffering:
            # The caller won't be using any sock.recv() calls, so buffering
            # is fine and recommended for performance.
            self.fp = sock.makefile('rb')
        else:
            # The buffer size is specified as zero, because the headers of
            # the response are read with readline().  If the reads were
            # buffered the readline() calls could consume some of the
            # response, which make be read via a recv() on the underlying
            # socket.
            self.fp = sock.makefile('rb', 0)
        self.debuglevel = debuglevel
        self.strict = strict
        self._method = method

        self.msg = None

        # from the Status-Line of the response
        self.version = _UNKNOWN # HTTP-Version
        self.status = _UNKNOWN  # Status-Code
        self.reason = _UNKNOWN  # Reason-Phrase

        self.chunked = _UNKNOWN         # is "chunked" being used?
        self.chunk_left = _UNKNOWN      # bytes left to read in current chunk
        self.length = _UNKNOWN          # number of bytes left in response
        self.will_close = _UNKNOWN      # conn will close at end of response

    def _read_status(self):
        # Initialize with Simple-Response defaults
        line = self.fp.readline(_MAXLINE + 1)
        if len(line) > _MAXLINE:
            raise LineTooLong("header line")
        if self.debuglevel > 0:
            print "reply:", repr(line)
        if not line:
            # Presumably, the server closed the connection before
            # sending a valid response.
            raise BadStatusLine(line)
        try:
            [version, status, reason] = line.split(None, 2)
        except ValueError:
            try:
                [version, status] = line.split(None, 1)
                reason = ""
            except ValueError:
                # empty version will cause next test to fail and status
                # will be treated as 0.9 response.
                version = ""
        if not version.startswith('HTTP/'):
            if self.strict:
                self.close()
                raise BadStatusLine(line)
            else:
                # assume it's a Simple-Response from an 0.9 server
                self.fp = LineAndFileWrapper(line, self.fp)
                return "HTTP/0.9", 200, ""

        # The status code is a three-digit number
        try:
            status = int(status)
            if status < 100 or status > 999:
                raise BadStatusLine(line)
        except ValueError:
            raise BadStatusLine(line)
        return version, status, reason

    def begin(self):
        if self.msg is not None:
            # we've already started reading the response
            return

        # read until we get a non-100 response
        while True:
            version, status, reason = self._read_status()
            if status != CONTINUE:
                break
            # skip the header from the 100 response
            while True:
                skip = self.fp.readline(_MAXLINE + 1)
                if len(skip) > _MAXLINE:
                    raise LineTooLong("header line")
                skip = skip.strip()
                if not skip:
                    break
                if self.debuglevel > 0:
                    print "header:", skip

        self.status = status
        self.reason = reason.strip()
        if version == 'HTTP/1.0':
            self.version = 10
        elif version.startswith('HTTP/1.'):
            self.version = 11   # use HTTP/1.1 code for HTTP/1.x where x>=1
        elif version == 'HTTP/0.9':
            self.version = 9
        else:
            raise UnknownProtocol(version)

        if self.version == 9:
            self.length = None
            self.chunked = 0
            self.will_close = 1
            self.msg = HTTPMessage(StringIO())
            return

        self.msg = HTTPMessage(self.fp, 0)
        if self.debuglevel > 0:
            for hdr in self.msg.headers:
                print "header:", hdr,

        # don't let the msg keep an fp
        self.msg.fp = None

        # are we using the chunked-style of transfer encoding?
        tr_enc = self.msg.getheader('transfer-encoding')
        if tr_enc and tr_enc.lower() == "chunked":
            self.chunked = 1
            self.chunk_left = None
        else:
            self.chunked = 0

        # will the connection close at the end of the response?
        self.will_close = self._check_close()

        # do we have a Content-Length?
        # NOTE: RFC 2616, S4.4, #3 says we ignore this if tr_enc is "chunked"
        length = self.msg.getheader('content-length')
        if length and not self.chunked:
            try:
                self.length = int(length)
            except ValueError:
                self.length = None
            else:
                if self.length < 0:  # ignore nonsensical negative lengths
                    self.length = None
        else:
            self.length = None

        # does the body have a fixed length? (of zero)
        if (status == NO_CONTENT or status == NOT_MODIFIED or
            100 <= status < 200 or      # 1xx codes
            self._method == 'HEAD'):
            self.length = 0

        # if the connection remains open, and we aren't using chunked, and
        # a content-length was not provided, then assume that the connection
        # WILL close.
        if not self.will_close and \
           not self.chunked and \
           self.length is None:
            self.will_close = 1

    def _check_close(self):
        conn = self.msg.getheader('connection')
        if self.version == 11:
            # An HTTP/1.1 proxy is assumed to stay open unless
            # explicitly closed.
            conn = self.msg.getheader('connection')
            if conn and "close" in conn.lower():
                return True
            return False

        # Some HTTP/1.0 implementations have support for persistent
        # connections, using rules different than HTTP/1.1.

        # For older HTTP, Keep-Alive indicates persistent connection.
        if self.msg.getheader('keep-alive'):
            return False

        # At least Akamai returns a "Connection: Keep-Alive" header,
        # which was supposed to be sent by the client.
        if conn and "keep-alive" in conn.lower():
            return False

        # Proxy-Connection is a netscape hack.
        pconn = self.msg.getheader('proxy-connection')
        if pconn and "keep-alive" in pconn.lower():
            return False

        # otherwise, assume it will close
        return True

    def close(self):
        fp = self.fp
        if fp:
            self.fp = None
            fp.close()

    def isclosed(self):
        # NOTE: it is possible that we will not ever call self.close(). This
        #       case occurs when will_close is TRUE, length is None, and we
        #       read up to the last byte, but NOT past it.
        #
        # IMPLIES: if will_close is FALSE, then self.close() will ALWAYS be
        #          called, meaning self.isclosed() is meaningful.
        return self.fp is None

    # XXX It would be nice to have readline and __iter__ for this, too.

    def read(self, amt=None):
        if self.fp is None:
            return ''

        if self._method == 'HEAD':
            self.close()
            return ''

        if self.chunked:
            return self._read_chunked(amt)

        if amt is None:
            # unbounded read
            if self.length is None:
                s = self.fp.read()
            else:
                try:
                    s = self._safe_read(self.length)
                except IncompleteRead:
                    self.close()
                    raise
                self.length = 0
            self.close()        # we read everything
            return s

        if self.length is not None:
            if amt > self.length:
                # clip the read to the "end of response"
                amt = self.length

        # we do not use _safe_read() here because this may be a .will_close
        # connection, and the user is reading more bytes than will be provided
        # (for example, reading in 1k chunks)
        s = self.fp.read(amt)
        if not s and amt:
            # Ideally, we would raise IncompleteRead if the content-length
            # wasn't satisfied, but it might break compatibility.
            self.close()
        if self.length is not None:
            self.length -= len(s)
            if not self.length:
                self.close()

        return s

    def _read_chunked(self, amt):
        assert self.chunked != _UNKNOWN
        chunk_left = self.chunk_left
        value = []
        while True:
            if chunk_left is None:
                line = self.fp.readline(_MAXLINE + 1)
                if len(line) > _MAXLINE:
                    raise LineTooLong("chunk size")
                i = line.find(';')
                if i >= 0:
                    line = line[:i] # strip chunk-extensions
                try:
                    chunk_left = int(line, 16)
                except ValueError:
                    # close the connection as protocol synchronisation is
                    # probably lost
                    self.close()
                    raise IncompleteRead(''.join(value))
                if chunk_left == 0:
                    break
            if amt is None:
                value.append(self._safe_read(chunk_left))
            elif amt < chunk_left:
                value.append(self._safe_read(amt))
                self.chunk_left = chunk_left - amt
                return ''.join(value)
            elif amt == chunk_left:
                value.append(self._safe_read(amt))
                self._safe_read(2)  # toss the CRLF at the end of the chunk
                self.chunk_left = None
                return ''.join(value)
            else:
                value.append(self._safe_read(chunk_left))
                amt -= chunk_left

            # we read the whole chunk, get another
            self._safe_read(2)      # toss the CRLF at the end of the chunk
            chunk_left = None

        # read and discard trailer up to the CRLF terminator
        ### note: we shouldn't have any trailers!
        while True:
            line = self.fp.readline(_MAXLINE + 1)
            if len(line) > _MAXLINE:
                raise LineTooLong("trailer line")
            if not line:
                # a vanishingly small number of sites EOF without
                # sending the trailer
                break
            if line == '\r\n':
                break

        # we read everything; close the "file"
        self.close()

        return ''.join(value)

    def _safe_read(self, amt):
        """Read the number of bytes requested, compensating for partial reads.

        Normally, we have a blocking socket, but a read() can be interrupted
        by a signal (resulting in a partial read).

        Note that we cannot distinguish between EOF and an interrupt when zero
        bytes have been read. IncompleteRead() will be raised in this
        situation.

        This function should be used when <amt> bytes "should" be present for
        reading. If the bytes are truly not available (due to EOF), then the
        IncompleteRead exception can be used to detect the problem.
        """
        # NOTE(gps): As of svn r74426 socket._fileobject.read(x) will never
        # return less than x bytes unless EOF is encountered.  It now handles
        # signal interruptions (socket.error EINTR) internally.  This code
        # never caught that exception anyways.  It seems largely pointless.
        # self.fp.read(amt) will work fine.
        s = []
        while amt > 0:
            chunk = self.fp.read(min(amt, MAXAMOUNT))
            if not chunk:
                raise IncompleteRead(''.join(s), amt)
            s.append(chunk)
            amt -= len(chunk)
        return ''.join(s)

    def fileno(self):
        return self.fp.fileno()

    def getheader(self, name, default=None):
        if self.msg is None:
            raise ResponseNotReady()
        return self.msg.getheader(name, default)

    def getheaders(self):
        """Return list of (header, value) tuples."""
        if self.msg is None:
            raise ResponseNotReady()
        return self.msg.items()


class HTTPConnection:

    _http_vsn = 11
    _http_vsn_str = 'HTTP/1.1'

    response_class = HTTPResponse
    default_port = HTTP_PORT
    auto_open = 1
    debuglevel = 0
    strict = 0

    def __init__(self, host, port=None, strict=None,
                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None):
        self.timeout = timeout
        self.source_address = source_address
        self.sock = None
        self._buffer = []
        self.__response = None
        self.__state = _CS_IDLE
        self._method = None
        self._tunnel_host = None
        self._tunnel_port = None
        self._tunnel_headers = {}
        if strict is not None:
            self.strict = strict

        (self.host, self.port) = self._get_hostport(host, port)

        # This is stored as an instance variable to allow unittests
        # to replace with a suitable mock
        self._create_connection = socket.create_connection

    def set_tunnel(self, host, port=None, headers=None):
        """ Set up host and port for HTTP CONNECT tunnelling.

        In a connection that uses HTTP Connect tunneling, the host passed to the
        constructor is used as proxy server that relays all communication to the
        endpoint passed to set_tunnel. This is done by sending a HTTP CONNECT
        request to the proxy server when the connection is established.

        This method must be called before the HTTP connection has been
        established.

        The headers argument should be a mapping of extra HTTP headers
        to send with the CONNECT request.
        """
        # Verify if this is required.
        if self.sock:
            raise RuntimeError("Can't setup tunnel for established connection.")

        self._tunnel_host, self._tunnel_port = self._get_hostport(host, port)
        if headers:
            self._tunnel_headers = headers
        else:
            self._tunnel_headers.clear()

    def _get_hostport(self, host, port):
        if port is None:
            i = host.rfind(':')
            j = host.rfind(']')         # ipv6 addresses have [...]
            if i > j:
                try:
                    port = int(host[i+1:])
                except ValueError:
                    if host[i+1:] == "":  # http://foo.com:/ == http://foo.com/
                        port = self.default_port
                    else:
                        raise InvalidURL("nonnumeric port: '%s'" % host[i+1:])
                host = host[:i]
            else:
                port = self.default_port
            if host and host[0] == '[' and host[-1] == ']':
                host = host[1:-1]
        return (host, port)

    def set_debuglevel(self, level):
        self.debuglevel = level

    def _tunnel(self):
        self.send("CONNECT %s:%d HTTP/1.0\r\n" % (self._tunnel_host,
            self._tunnel_port))
        for header, value in self._tunnel_headers.iteritems():
            self.send("%s: %s\r\n" % (header, value))
        self.send("\r\n")
        response = self.response_class(self.sock, strict = self.strict,
                                       method = self._method)
        (version, code, message) = response._read_status()

        if version == "HTTP/0.9":
            # HTTP/0.9 doesn't support the CONNECT verb, so if httplib has
            # concluded HTTP/0.9 is being used something has gone wrong.
            self.close()
            raise socket.error("Invalid response from tunnel request")
        if code != 200:
            self.close()
            raise socket.error("Tunnel connection failed: %d %s" % (code,
                                                                    message.strip()))
        while True:
            line = response.fp.readline(_MAXLINE + 1)
            if len(line) > _MAXLINE:
                raise LineTooLong("header line")
            if not line:
                # for sites which EOF without sending trailer
                break
            if line == '\r\n':
                break


    def connect(self):
        """Connect to the host and port specified in __init__."""
        self.sock = self._create_connection((self.host,self.port),
                                           self.timeout, self.source_address)

        if self._tunnel_host:
            self._tunnel()

    def close(self):
        """Close the connection to the HTTP server."""
        self.__state = _CS_IDLE
        try:
            sock = self.sock
            if sock:
                self.sock = None
                sock.close()   # close it manually... there may be other refs
        finally:
            response = self.__response
            if response:
                self.__response = None
                response.close()

    def send(self, data):
        """Send `data' to the server."""
        if self.sock is None:
            if self.auto_open:
                self.connect()
            else:
                raise NotConnected()

        if self.debuglevel > 0:
            print "send:", repr(data)
        blocksize = 8192
        if hasattr(data,'read') and not isinstance(data, array):
            if self.debuglevel > 0: print "sendIng a read()able"
            datablock = data.read(blocksize)
            while datablock:
                self.sock.sendall(datablock)
                datablock = data.read(blocksize)
        else:
            self.sock.sendall(data)

    def _output(self, s):
        """Add a line of output to the current request buffer.

        Assumes that the line does *not* end with \\r\\n.
        """
        self._buffer.append(s)

    def _send_output(self, message_body=None):
        """Send the currently buffered request and clear the buffer.

        Appends an extra \\r\\n to the buffer.
        A message_body may be specified, to be appended to the request.
        """
        self._buffer.extend(("", ""))
        msg = "\r\n".join(self._buffer)
        del self._buffer[:]
        # If msg and message_body are sent in a single send() call,
        # it will avoid performance problems caused by the interaction
        # between delayed ack and the Nagle algorithm.
        if isinstance(message_body, str):
            msg += message_body
            message_body = None
        self.send(msg)
        if message_body is not None:
            #message_body was not a string (i.e. it is a file) and
            #we must run the risk of Nagle
            self.send(message_body)

    def putrequest(self, method, url, skip_host=0, skip_accept_encoding=0):
        """Send a request to the server.

        `method' specifies an HTTP request method, e.g. 'GET'.
        `url' specifies the object being requested, e.g. '/index.html'.
        `skip_host' if True does not add automatically a 'Host:' header
        `skip_accept_encoding' if True does not add automatically an
           'Accept-Encoding:' header
        """

        # if a prior response has been completed, then forget about it.
        if self.__response and self.__response.isclosed():
            self.__response = None


        # in certain cases, we cannot issue another request on this connection.
        # this occurs when:
        #   1) we are in the process of sending a request.   (_CS_REQ_STARTED)
        #   2) a response to a previous request has signalled that it is going
        #      to close the connection upon completion.
        #   3) the headers for the previous response have not been read, thus
        #      we cannot determine whether point (2) is true.   (_CS_REQ_SENT)
        #
        # if there is no prior response, then we can request at will.
        #
        # if point (2) is true, then we will have passed the socket to the
        # response (effectively meaning, "there is no prior response"), and
        # will open a new one when a new request is made.
        #
        # Note: if a prior response exists, then we *can* start a new request.
        #       We are not allowed to begin fetching the response to this new
        #       request, however, until that prior response is complete.
        #
        if self.__state == _CS_IDLE:
            self.__state = _CS_REQ_STARTED
        else:
            raise CannotSendRequest()

        # Save the method we use, we need it later in the response phase
        self._method = method
        if not url:
            url = '/'
        hdr = '%s %s %s' % (method, url, self._http_vsn_str)

        self._output(hdr)

        if self._http_vsn == 11:
            # Issue some standard headers for better HTTP/1.1 compliance

            if not skip_host:
                # this header is issued *only* for HTTP/1.1
                # connections. more specifically, this means it is
                # only issued when the client uses the new
                # HTTPConnection() class. backwards-compat clients
                # will be using HTTP/1.0 and those clients may be
                # issuing this header themselves. we should NOT issue
                # it twice; some web servers (such as Apache) barf
                # when they see two Host: headers

                # If we need a non-standard port,include it in the
                # header.  If the request is going through a proxy,
                # but the host of the actual URL, not the host of the
                # proxy.

                netloc = ''
                if url.startswith('http'):
                    nil, netloc, nil, nil, nil = urlsplit(url)

                if netloc:
                    try:
                        netloc_enc = netloc.encode("ascii")
                    except UnicodeEncodeError:
                        netloc_enc = netloc.encode("idna")
                    self.putheader('Host', netloc_enc)
                else:
                    if self._tunnel_host:
                        host = self._tunnel_host
                        port = self._tunnel_port
                    else:
                        host = self.host
                        port = self.port

                    try:
                        host_enc = host.encode("ascii")
                    except UnicodeEncodeError:
                        host_enc = host.encode("idna")
                    # Wrap the IPv6 Host Header with [] (RFC 2732)
                    if host_enc.find(':') >= 0:
                        host_enc = "[" + host_enc + "]"
                    if port == self.default_port:
                        self.putheader('Host', host_enc)
                    else:
                        self.putheader('Host', "%s:%s" % (host_enc, port))

            # note: we are assuming that clients will not attempt to set these
            #       headers since *this* library must deal with the
            #       consequences. this also means that when the supporting
            #       libraries are updated to recognize other forms, then this
            #       code should be changed (removed or updated).

            # we only want a Content-Encoding of "identity" since we don't
            # support encodings such as x-gzip or x-deflate.
            if not skip_accept_encoding:
                self.putheader('Accept-Encoding', 'identity')

            # we can accept "chunked" Transfer-Encodings, but no others
            # NOTE: no TE header implies *only* "chunked"
            #self.putheader('TE', 'chunked')

            # if TE is supplied in the header, then it must appear in a
            # Connection header.
            #self.putheader('Connection', 'TE')

        else:
            # For HTTP/1.0, the server will assume "not chunked"
            pass

    def putheader(self, header, *values):
        """Send a request header line to the server.

        For example: h.putheader('Accept', 'text/html')
        """
        if self.__state != _CS_REQ_STARTED:
            raise CannotSendHeader()

        header = '%s' % header
        if not _is_legal_header_name(header):
            raise ValueError('Invalid header name %r' % (header,))

        values = [str(v) for v in values]
        for one_value in values:
            if _is_illegal_header_value(one_value):
                raise ValueError('Invalid header value %r' % (one_value,))

        hdr = '%s: %s' % (header, '\r\n\t'.join(values))
        self._output(hdr)

    def endheaders(self, message_body=None):
        """Indicate that the last header line has been sent to the server.

        This method sends the request to the server.  The optional
        message_body argument can be used to pass a message body
        associated with the request.  The message body will be sent in
        the same packet as the message headers if it is string, otherwise it is
        sent as a separate packet.
        """
        if self.__state == _CS_REQ_STARTED:
            self.__state = _CS_REQ_SENT
        else:
            raise CannotSendHeader()
        self._send_output(message_body)

    def request(self, method, url, body=None, headers={}):
        """Send a complete request to the server."""
        self._send_request(method, url, body, headers)

    def _set_content_length(self, body, method):
        # Set the content-length based on the body. If the body is "empty", we
        # set Content-Length: 0 for methods that expect a body (RFC 7230,
        # Section 3.3.2). If the body is set for other methods, we set the
        # header provided we can figure out what the length is.
        thelen = None
        if body is None and method.upper() in _METHODS_EXPECTING_BODY:
            thelen = '0'
        elif body is not None:
            try:
                thelen = str(len(body))
            except (TypeError, AttributeError):
                # If this is a file-like object, try to
                # fstat its file descriptor
                try:
                    thelen = str(os.fstat(body.fileno()).st_size)
                except (AttributeError, OSError):
                    # Don't send a length if this failed
                    if self.debuglevel > 0: print "Cannot stat!!"

        if thelen is not None:
            self.putheader('Content-Length', thelen)

    def _send_request(self, method, url, body, headers):
        # Honor explicitly requested Host: and Accept-Encoding: headers.
        header_names = dict.fromkeys([k.lower() for k in headers])
        skips = {}
        if 'host' in header_names:
            skips['skip_host'] = 1
        if 'accept-encoding' in header_names:
            skips['skip_accept_encoding'] = 1

        self.putrequest(method, url, **skips)

        if 'content-length' not in header_names:
            self._set_content_length(body, method)
        for hdr, value in headers.iteritems():
            self.putheader(hdr, value)
        self.endheaders(body)

    def getresponse(self, buffering=False):
        "Get the response from the server."

        # if a prior response has been completed, then forget about it.
        if self.__response and self.__response.isclosed():
            self.__response = None

        #
        # if a prior response exists, then it must be completed (otherwise, we
        # cannot read this response's header to determine the connection-close
        # behavior)
        #
        # note: if a prior response existed, but was connection-close, then the
        # socket and response were made independent of this HTTPConnection
        # object since a new request requires that we open a whole new
        # connection
        #
        # this means the prior response had one of two states:
        #   1) will_close: this connection was reset and the prior socket and
        #                  response operate independently
        #   2) persistent: the response was retained and we await its
        #                  isclosed() status to become true.
        #
        if self.__state != _CS_REQ_SENT or self.__response:
            raise ResponseNotReady()

        args = (self.sock,)
        kwds = {"strict":self.strict, "method":self._method}
        if self.debuglevel > 0:
            args += (self.debuglevel,)
        if buffering:
            #only add this keyword if non-default, for compatibility with
            #other response_classes.
            kwds["buffering"] = True;
        response = self.response_class(*args, **kwds)

        try:
            response.begin()
            assert response.will_close != _UNKNOWN
            self.__state = _CS_IDLE

            if response.will_close:
                # this effectively passes the connection to the response
                self.close()
            else:
                # remember this, so we can tell when it is complete
                self.__response = response

            return response
        except:
            response.close()
            raise


class HTTP:
    "Compatibility class with httplib.py from 1.5."

    _http_vsn = 10
    _http_vsn_str = 'HTTP/1.0'

    debuglevel = 0

    _connection_class = HTTPConnection

    def __init__(self, host='', port=None, strict=None):
        "Provide a default host, since the superclass requires one."

        # some joker passed 0 explicitly, meaning default port
        if port == 0:
            port = None

        # Note that we may pass an empty string as the host; this will raise
        # an error when we attempt to connect. Presumably, the client code
        # will call connect before then, with a proper host.
        self._setup(self._connection_class(host, port, strict))

    def _setup(self, conn):
        self._conn = conn

        # set up delegation to flesh out interface
        self.send = conn.send
        self.putrequest = conn.putrequest
        self.putheader = conn.putheader
        self.endheaders = conn.endheaders
        self.set_debuglevel = conn.set_debuglevel

        conn._http_vsn = self._http_vsn
        conn._http_vsn_str = self._http_vsn_str

        self.file = None

    def connect(self, host=None, port=None):
        "Accept arguments to set the host/port, since the superclass doesn't."

        if host is not None:
            (self._conn.host, self._conn.port) = self._conn._get_hostport(host, port)
        self._conn.connect()

    def getfile(self):
        "Provide a getfile, since the superclass' does not use this concept."
        return self.file

    def getreply(self, buffering=False):
        """Compat definition since superclass does not define it.

        Returns a tuple consisting of:
        - server status code (e.g. '200' if all goes well)
        - server "reason" corresponding to status code
        - any RFC822 headers in the response from the server
        """
        try:
            if not buffering:
                response = self._conn.getresponse()
            else:
                #only add this keyword if non-default for compatibility
                #with other connection classes
                response = self._conn.getresponse(buffering)
        except BadStatusLine, e:
            ### hmm. if getresponse() ever closes the socket on a bad request,
            ### then we are going to have problems with self.sock

            ### should we keep this behavior? do people use it?
            # keep the socket open (as a file), and return it
            self.file = self._conn.sock.makefile('rb', 0)

            # close our socket -- we want to restart after any protocol error
            self.close()

            self.headers = None
            return -1, e.line, None

        self.headers = response.msg
        self.file = response.fp
        return response.status, response.reason, response.msg

    def close(self):
        self._conn.close()

        # note that self.file == response.fp, which gets closed by the
        # superclass. just clear the object ref here.
        ### hmm. messy. if status==-1, then self.file is owned by us.
        ### well... we aren't explicitly closing, but losing this ref will
        ### do it
        self.file = None

try:
    import ssl
except ImportError:
    pass
else:
    class HTTPSConnection(HTTPConnection):
        "This class allows communication via SSL."

        default_port = HTTPS_PORT

        def __init__(self, host, port=None, key_file=None, cert_file=None,
                     strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
                     source_address=None, context=None):
            HTTPConnection.__init__(self, host, port, strict, timeout,
                                    source_address)
            self.key_file = key_file
            self.cert_file = cert_file
            if context is None:
                context = ssl._create_default_https_context()
            if key_file or cert_file:
                context.load_cert_chain(cert_file, key_file)
            self._context = context

        def connect(self):
            "Connect to a host on a given (SSL) port."

            HTTPConnection.connect(self)

            if self._tunnel_host:
                server_hostname = self._tunnel_host
            else:
                server_hostname = self.host

            self.sock = self._context.wrap_socket(self.sock,
                                                  server_hostname=server_hostname)

    __all__.append("HTTPSConnection")

    class HTTPS(HTTP):
        """Compatibility with 1.5 httplib interface

        Python 1.5.2 did not have an HTTPS class, but it defined an
        interface for sending http requests that is also useful for
        https.
        """

        _connection_class = HTTPSConnection

        def __init__(self, host='', port=None, key_file=None, cert_file=None,
                     strict=None, context=None):
            # provide a default host, pass the X509 cert info

            # urf. compensate for bad input.
            if port == 0:
                port = None
            self._setup(self._connection_class(host, port, key_file,
                                               cert_file, strict,
                                               context=context))

            # we never actually use these for anything, but we keep them
            # here for compatibility with post-1.5.2 CVS.
            self.key_file = key_file
            self.cert_file = cert_file


    def FakeSocket (sock, sslobj):
        warnings.warn("FakeSocket is deprecated, and won't be in 3.x.  " +
                      "Use the result of ssl.wrap_socket() directly instead.",
                      DeprecationWarning, stacklevel=2)
        return sslobj


class HTTPException(Exception):
    # Subclasses that define an __init__ must call Exception.__init__
    # or define self.args.  Otherwise, str() will fail.
    pass

class NotConnected(HTTPException):
    pass

class InvalidURL(HTTPException):
    pass

class UnknownProtocol(HTTPException):
    def __init__(self, version):
        self.args = version,
        self.version = version

class UnknownTransferEncoding(HTTPException):
    pass

class UnimplementedFileMode(HTTPException):
    pass

class IncompleteRead(HTTPException):
    def __init__(self, partial, expected=None):
        self.args = partial,
        self.partial = partial
        self.expected = expected
    def __repr__(self):
        if self.expected is not None:
            e = ', %i more expected' % self.expected
        else:
            e = ''
        return 'IncompleteRead(%i bytes read%s)' % (len(self.partial), e)
    def __str__(self):
        return repr(self)

class ImproperConnectionState(HTTPException):
    pass

class CannotSendRequest(ImproperConnectionState):
    pass

class CannotSendHeader(ImproperConnectionState):
    pass

class ResponseNotReady(ImproperConnectionState):
    pass

class BadStatusLine(HTTPException):
    def __init__(self, line):
        if not line:
            line = repr(line)
        self.args = line,
        self.line = line

class LineTooLong(HTTPException):
    def __init__(self, line_type):
        HTTPException.__init__(self, "got more than %d bytes when reading %s"
                                     % (_MAXLINE, line_type))

# for backwards compatibility
error = HTTPException

class LineAndFileWrapper:
    """A limited file-like object for HTTP/0.9 responses."""

    # The status-line parsing code calls readline(), which normally
    # get the HTTP status line.  For a 0.9 response, however, this is
    # actually the first line of the body!  Clients need to get a
    # readable file object that contains that line.

    def __init__(self, line, file):
        self._line = line
        self._file = file
        self._line_consumed = 0
        self._line_offset = 0
        self._line_left = len(line)

    def __getattr__(self, attr):
        return getattr(self._file, attr)

    def _done(self):
        # called when the last byte is read from the line.  After the
        # call, all read methods are delegated to the underlying file
        # object.
        self._line_consumed = 1
        self.read = self._file.read
        self.readline = self._file.readline
        self.readlines = self._file.readlines

    def read(self, amt=None):
        if self._line_consumed:
            return self._file.read(amt)
        assert self._line_left
        if amt is None or amt > self._line_left:
            s = self._line[self._line_offset:]
            self._done()
            if amt is None:
                return s + self._file.read()
            else:
                return s + self._file.read(amt - len(s))
        else:
            assert amt <= self._line_left
            i = self._line_offset
            j = i + amt
            s = self._line[i:j]
            self._line_offset = j
            self._line_left -= amt
            if self._line_left == 0:
                self._done()
            return s

    def readline(self):
        if self._line_consumed:
            return self._file.readline()
        assert self._line_left
        s = self._line[self._line_offset:]
        self._done()
        return s

    def readlines(self, size=None):
        if self._line_consumed:
            return self._file.readlines(size)
        assert self._line_left
        L = [self._line[self._line_offset:]]
        self._done()
        if size is None:
            return L + self._file.readlines()
        else:
            return L + self._file.readlines(size)