| 1 | n/a | """Python 'zlib_codec' Codec - zlib compression encoding. |
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| 2 | n/a | |
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| 3 | n/a | This codec de/encodes from bytes to bytes. |
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| 4 | n/a | |
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| 5 | n/a | Written by Marc-Andre Lemburg (mal@lemburg.com). |
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| 6 | n/a | """ |
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| 7 | n/a | |
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| 8 | n/a | import codecs |
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| 9 | n/a | import zlib # this codec needs the optional zlib module ! |
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| 10 | n/a | |
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| 11 | n/a | ### Codec APIs |
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| 12 | n/a | |
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| 13 | n/a | def zlib_encode(input, errors='strict'): |
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| 14 | n/a | assert errors == 'strict' |
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| 15 | n/a | return (zlib.compress(input), len(input)) |
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| 16 | n/a | |
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| 17 | n/a | def zlib_decode(input, errors='strict'): |
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| 18 | n/a | assert errors == 'strict' |
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| 19 | n/a | return (zlib.decompress(input), len(input)) |
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| 20 | n/a | |
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| 21 | n/a | class Codec(codecs.Codec): |
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| 22 | n/a | def encode(self, input, errors='strict'): |
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| 23 | n/a | return zlib_encode(input, errors) |
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| 24 | n/a | def decode(self, input, errors='strict'): |
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| 25 | n/a | return zlib_decode(input, errors) |
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| 26 | n/a | |
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| 27 | n/a | class IncrementalEncoder(codecs.IncrementalEncoder): |
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| 28 | n/a | def __init__(self, errors='strict'): |
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| 29 | n/a | assert errors == 'strict' |
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| 30 | n/a | self.errors = errors |
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| 31 | n/a | self.compressobj = zlib.compressobj() |
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| 32 | n/a | |
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| 33 | n/a | def encode(self, input, final=False): |
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| 34 | n/a | if final: |
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| 35 | n/a | c = self.compressobj.compress(input) |
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| 36 | n/a | return c + self.compressobj.flush() |
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| 37 | n/a | else: |
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| 38 | n/a | return self.compressobj.compress(input) |
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| 39 | n/a | |
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| 40 | n/a | def reset(self): |
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| 41 | n/a | self.compressobj = zlib.compressobj() |
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| 42 | n/a | |
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| 43 | n/a | class IncrementalDecoder(codecs.IncrementalDecoder): |
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| 44 | n/a | def __init__(self, errors='strict'): |
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| 45 | n/a | assert errors == 'strict' |
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| 46 | n/a | self.errors = errors |
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| 47 | n/a | self.decompressobj = zlib.decompressobj() |
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| 48 | n/a | |
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| 49 | n/a | def decode(self, input, final=False): |
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| 50 | n/a | if final: |
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| 51 | n/a | c = self.decompressobj.decompress(input) |
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| 52 | n/a | return c + self.decompressobj.flush() |
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| 53 | n/a | else: |
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| 54 | n/a | return self.decompressobj.decompress(input) |
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| 55 | n/a | |
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| 56 | n/a | def reset(self): |
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| 57 | n/a | self.decompressobj = zlib.decompressobj() |
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| 58 | n/a | |
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| 59 | n/a | class StreamWriter(Codec, codecs.StreamWriter): |
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| 60 | n/a | charbuffertype = bytes |
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| 61 | n/a | |
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| 62 | n/a | class StreamReader(Codec, codecs.StreamReader): |
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| 63 | n/a | charbuffertype = bytes |
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| 64 | n/a | |
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| 65 | n/a | ### encodings module API |
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| 66 | n/a | |
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| 67 | n/a | def getregentry(): |
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| 68 | n/a | return codecs.CodecInfo( |
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| 69 | n/a | name='zlib', |
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| 70 | n/a | encode=zlib_encode, |
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| 71 | n/a | decode=zlib_decode, |
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| 72 | n/a | incrementalencoder=IncrementalEncoder, |
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| 73 | n/a | incrementaldecoder=IncrementalDecoder, |
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| 74 | n/a | streamreader=StreamReader, |
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| 75 | n/a | streamwriter=StreamWriter, |
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| 76 | n/a | _is_text_encoding=False, |
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| 77 | n/a | ) |
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