2363d6de43
git-svn-id: http://google-refine.googlecode.com/svn/trunk@517 7d457c2a-affb-35e4-300a-418c747d4874
129 lines
3.6 KiB
Python
129 lines
3.6 KiB
Python
""" Python 'uu_codec' Codec - UU content transfer encoding
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Unlike most of the other codecs which target Unicode, this codec
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will return Python string objects for both encode and decode.
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Written by Marc-Andre Lemburg (mal@lemburg.com). Some details were
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adapted from uu.py which was written by Lance Ellinghouse and
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modified by Jack Jansen and Fredrik Lundh.
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"""
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import codecs, binascii
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### Codec APIs
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def uu_encode(input,errors='strict',filename='<data>',mode=0666):
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""" Encodes the object input and returns a tuple (output
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object, length consumed).
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errors defines the error handling to apply. It defaults to
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'strict' handling which is the only currently supported
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error handling for this codec.
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"""
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assert errors == 'strict'
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from cStringIO import StringIO
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from binascii import b2a_uu
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infile = StringIO(input)
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outfile = StringIO()
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read = infile.read
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write = outfile.write
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# Encode
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write('begin %o %s\n' % (mode & 0777, filename))
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chunk = read(45)
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while chunk:
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write(b2a_uu(chunk))
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chunk = read(45)
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write(' \nend\n')
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return (outfile.getvalue(), len(input))
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def uu_decode(input,errors='strict'):
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""" Decodes the object input and returns a tuple (output
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object, length consumed).
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input must be an object which provides the bf_getreadbuf
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buffer slot. Python strings, buffer objects and memory
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mapped files are examples of objects providing this slot.
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errors defines the error handling to apply. It defaults to
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'strict' handling which is the only currently supported
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error handling for this codec.
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Note: filename and file mode information in the input data is
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ignored.
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"""
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assert errors == 'strict'
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from cStringIO import StringIO
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from binascii import a2b_uu
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infile = StringIO(input)
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outfile = StringIO()
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readline = infile.readline
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write = outfile.write
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# Find start of encoded data
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while 1:
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s = readline()
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if not s:
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raise ValueError, 'Missing "begin" line in input data'
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if s[:5] == 'begin':
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break
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# Decode
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while 1:
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s = readline()
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if not s or \
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s == 'end\n':
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break
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try:
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data = a2b_uu(s)
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except binascii.Error, v:
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# Workaround for broken uuencoders by /Fredrik Lundh
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nbytes = (((ord(s[0])-32) & 63) * 4 + 5) / 3
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data = a2b_uu(s[:nbytes])
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#sys.stderr.write("Warning: %s\n" % str(v))
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write(data)
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if not s:
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raise ValueError, 'Truncated input data'
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return (outfile.getvalue(), len(input))
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class Codec(codecs.Codec):
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def encode(self,input,errors='strict'):
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return uu_encode(input,errors)
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def decode(self,input,errors='strict'):
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return uu_decode(input,errors)
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class IncrementalEncoder(codecs.IncrementalEncoder):
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def encode(self, input, final=False):
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return uu_encode(input, self.errors)[0]
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class IncrementalDecoder(codecs.IncrementalDecoder):
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def decode(self, input, final=False):
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return uu_decode(input, self.errors)[0]
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class StreamWriter(Codec,codecs.StreamWriter):
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pass
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class StreamReader(Codec,codecs.StreamReader):
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pass
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### encodings module API
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def getregentry():
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return codecs.CodecInfo(
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name='uu',
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encode=uu_encode,
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decode=uu_decode,
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incrementalencoder=IncrementalEncoder,
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incrementaldecoder=IncrementalDecoder,
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streamreader=StreamReader,
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streamwriter=StreamWriter,
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)
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