python-2.5.2/win32/Lib/encodings/bz2_codec.py
author jjkang
Fri, 11 Jun 2010 15:22:40 +0800
changeset 2 9da1e5517a66
parent 0 ae805ac0140d
permissions -rw-r--r--
Change SFL to EPL
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
0
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     1
""" Python 'bz2_codec' Codec - bz2 compression encoding
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     2
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     3
    Unlike most of the other codecs which target Unicode, this codec
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     4
    will return Python string objects for both encode and decode.
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     5
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     6
    Adapted by Raymond Hettinger from zlib_codec.py which was written
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     7
    by Marc-Andre Lemburg (mal@lemburg.com).
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     8
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
     9
"""
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    10
import codecs
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    11
import bz2 # this codec needs the optional bz2 module !
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    12
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    13
### Codec APIs
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    14
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    15
def bz2_encode(input,errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    16
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    17
    """ Encodes the object input and returns a tuple (output
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    18
        object, length consumed).
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    19
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    20
        errors defines the error handling to apply. It defaults to
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    21
        'strict' handling which is the only currently supported
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    22
        error handling for this codec.
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    23
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    24
    """
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    25
    assert errors == 'strict'
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    26
    output = bz2.compress(input)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    27
    return (output, len(input))
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    28
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    29
def bz2_decode(input,errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    30
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    31
    """ Decodes the object input and returns a tuple (output
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    32
        object, length consumed).
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    33
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    34
        input must be an object which provides the bf_getreadbuf
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    35
        buffer slot. Python strings, buffer objects and memory
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    36
        mapped files are examples of objects providing this slot.
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    37
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    38
        errors defines the error handling to apply. It defaults to
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    39
        'strict' handling which is the only currently supported
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    40
        error handling for this codec.
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    41
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    42
    """
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    43
    assert errors == 'strict'
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    44
    output = bz2.decompress(input)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    45
    return (output, len(input))
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    46
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    47
class Codec(codecs.Codec):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    48
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    49
    def encode(self, input, errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    50
        return bz2_encode(input, errors)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    51
    def decode(self, input, errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    52
        return bz2_decode(input, errors)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    53
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    54
class IncrementalEncoder(codecs.IncrementalEncoder):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    55
    def __init__(self, errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    56
        assert errors == 'strict'
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    57
        self.errors = errors
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    58
        self.compressobj = bz2.BZ2Compressor()
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    59
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    60
    def encode(self, input, final=False):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    61
        if final:
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    62
            c = self.compressobj.compress(input)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    63
            return c + self.compressobj.flush()
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    64
        else:
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    65
            return self.compressobj.compress(input)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    66
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    67
    def reset(self):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    68
        self.compressobj = bz2.BZ2Compressor()
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    69
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    70
class IncrementalDecoder(codecs.IncrementalDecoder):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    71
    def __init__(self, errors='strict'):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    72
        assert errors == 'strict'
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    73
        self.errors = errors
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    74
        self.decompressobj = bz2.BZ2Decompressor()
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    75
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    76
    def decode(self, input, final=False):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    77
        try:
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    78
            return self.decompressobj.decompress(input)
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    79
        except EOFError:
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    80
            return ''
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    81
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    82
    def reset(self):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    83
        self.decompressobj = bz2.BZ2Decompressor()
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    84
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    85
class StreamWriter(Codec,codecs.StreamWriter):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    86
    pass
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    87
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    88
class StreamReader(Codec,codecs.StreamReader):
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    89
    pass
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    90
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    91
### encodings module API
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    92
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    93
def getregentry():
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    94
    return codecs.CodecInfo(
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    95
        name="bz2",
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    96
        encode=bz2_encode,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    97
        decode=bz2_decode,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    98
        incrementalencoder=IncrementalEncoder,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
    99
        incrementaldecoder=IncrementalDecoder,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
   100
        streamwriter=StreamWriter,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
   101
        streamreader=StreamReader,
ae805ac0140d DP tools release version Revision: 200912
Deepak Modgil <Deepak.Modgil@Nokia.com>
parents:
diff changeset
   102
    )