99 lines
2.8 KiB
Python
99 lines
2.8 KiB
Python
"""Python 'uu_codec' Codec - UU content transfer 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). 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
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import binascii
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from io import BytesIO
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### Codec APIs
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def uu_encode(input, errors='strict', filename='<data>', mode=0o666):
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assert errors == 'strict'
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infile = BytesIO(input)
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outfile = BytesIO()
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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 & 0o777, filename)).encode('ascii'))
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chunk = read(45)
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while chunk:
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write(binascii.b2a_uu(chunk))
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chunk = read(45)
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write(b' \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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assert errors == 'strict'
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infile = BytesIO(input)
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outfile = BytesIO()
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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] == b'begin':
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break
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# Decode
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while True:
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s = readline()
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if not s or s == b'end\n':
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break
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try:
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data = binascii.a2b_uu(s)
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except binascii.Error as v:
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# Workaround for broken uuencoders by /Fredrik Lundh
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nbytes = (((s[0]-32) & 63) * 4 + 5) // 3
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data = binascii.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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charbuffertype = bytes
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class StreamReader(Codec, codecs.StreamReader):
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charbuffertype = bytes
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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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_is_text_encoding=False,
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)
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