openmedialibrary_platform/Darwin/lib/python3.4/encodings/bz2_codec.py

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"""Python 'bz2_codec' Codec - bz2 compression encoding.
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This codec de/encodes from bytes to bytes and is therefore usable with
bytes.transform() and bytes.untransform().
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Adapted by Raymond Hettinger from zlib_codec.py which was written
by Marc-Andre Lemburg (mal@lemburg.com).
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"""
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import codecs
import bz2 # this codec needs the optional bz2 module !
### Codec APIs
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def bz2_encode(input, errors='strict'):
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assert errors == 'strict'
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return (bz2.compress(input), len(input))
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def bz2_decode(input, errors='strict'):
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assert errors == 'strict'
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return (bz2.decompress(input), len(input))
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class Codec(codecs.Codec):
def encode(self, input, errors='strict'):
return bz2_encode(input, errors)
def decode(self, input, errors='strict'):
return bz2_decode(input, errors)
class IncrementalEncoder(codecs.IncrementalEncoder):
def __init__(self, errors='strict'):
assert errors == 'strict'
self.errors = errors
self.compressobj = bz2.BZ2Compressor()
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 = bz2.BZ2Compressor()
class IncrementalDecoder(codecs.IncrementalDecoder):
def __init__(self, errors='strict'):
assert errors == 'strict'
self.errors = errors
self.decompressobj = bz2.BZ2Decompressor()
def decode(self, input, final=False):
try:
return self.decompressobj.decompress(input)
except EOFError:
return ''
def reset(self):
self.decompressobj = bz2.BZ2Decompressor()
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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="bz2",
encode=bz2_encode,
decode=bz2_decode,
incrementalencoder=IncrementalEncoder,
incrementaldecoder=IncrementalDecoder,
streamwriter=StreamWriter,
streamreader=StreamReader,
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_is_text_encoding=False,
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)