openmedialibrary_platform/Darwin/lib/python3.4/encodings/zlib_codec.py

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"""Python 'zlib_codec' Codec - zlib compression encoding.
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This codec de/encodes from bytes to bytes.
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Written by Marc-Andre Lemburg (mal@lemburg.com).
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"""
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import codecs
import zlib # this codec needs the optional zlib module !
### Codec APIs
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def zlib_encode(input, errors='strict'):
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assert errors == 'strict'
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return (zlib.compress(input), len(input))
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def zlib_decode(input, errors='strict'):
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assert errors == 'strict'
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return (zlib.decompress(input), len(input))
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class Codec(codecs.Codec):
def encode(self, input, errors='strict'):
return zlib_encode(input, errors)
def decode(self, input, errors='strict'):
return zlib_decode(input, errors)
class IncrementalEncoder(codecs.IncrementalEncoder):
def __init__(self, errors='strict'):
assert errors == 'strict'
self.errors = errors
self.compressobj = zlib.compressobj()
def encode(self, input, final=False):
if final:
c = self.compressobj.compress(input)
return c + self.compressobj.flush()
else:
return self.compressobj.compress(input)
def reset(self):
self.compressobj = zlib.compressobj()
class IncrementalDecoder(codecs.IncrementalDecoder):
def __init__(self, errors='strict'):
assert errors == 'strict'
self.errors = errors
self.decompressobj = zlib.decompressobj()
def decode(self, input, final=False):
if final:
c = self.decompressobj.decompress(input)
return c + self.decompressobj.flush()
else:
return self.decompressobj.decompress(input)
def reset(self):
self.decompressobj = zlib.decompressobj()
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class StreamWriter(Codec, codecs.StreamWriter):
charbuffertype = bytes
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class StreamReader(Codec, codecs.StreamReader):
charbuffertype = bytes
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### encodings module API
def getregentry():
return codecs.CodecInfo(
name='zlib',
encode=zlib_encode,
decode=zlib_decode,
incrementalencoder=IncrementalEncoder,
incrementaldecoder=IncrementalDecoder,
streamreader=StreamReader,
streamwriter=StreamWriter,
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_is_text_encoding=False,
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)