79 lines
2.2 KiB
Python
79 lines
2.2 KiB
Python
|
"""Python 'bz2_codec' Codec - bz2 compression encoding.
|
||
|
|
|
||
|
|
This codec de/encodes from bytes to bytes and is therefore usable with
|
||
|
|
bytes.transform() and bytes.untransform().
|
||
|
|
|
||
|
|
Adapted by Raymond Hettinger from zlib_codec.py which was written
|
||
|
|
by Marc-Andre Lemburg (mal@lemburg.com).
|
||
|
|
"""
|
||
|
|
|
||
|
|
import codecs
|
||
|
|
import bz2 # this codec needs the optional bz2 module !
|
||
|
|
|
||
|
|
### Codec APIs
|
||
|
|
|
||
|
|
def bz2_encode(input, errors='strict'):
|
||
|
|
assert errors == 'strict'
|
||
|
|
return (bz2.compress(input), len(input))
|
||
|
|
|
||
|
|
def bz2_decode(input, errors='strict'):
|
||
|
|
assert errors == 'strict'
|
||
|
|
return (bz2.decompress(input), len(input))
|
||
|
|
|
||
|
|
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()
|
||
|
|
|
||
|
|
class StreamWriter(Codec, codecs.StreamWriter):
|
||
|
|
charbuffertype = bytes
|
||
|
|
|
||
|
|
class StreamReader(Codec, codecs.StreamReader):
|
||
|
|
charbuffertype = bytes
|
||
|
|
|
||
|
|
### encodings module API
|
||
|
|
|
||
|
|
def getregentry():
|
||
|
|
return codecs.CodecInfo(
|
||
|
|
name="bz2",
|
||
|
|
encode=bz2_encode,
|
||
|
|
decode=bz2_decode,
|
||
|
|
incrementalencoder=IncrementalEncoder,
|
||
|
|
incrementaldecoder=IncrementalDecoder,
|
||
|
|
streamwriter=StreamWriter,
|
||
|
|
streamreader=StreamReader,
|
||
|
|
_is_text_encoding=False,
|
||
|
|
)
|