jpayne@69: """Python 'uu_codec' Codec - UU content transfer encoding.
jpayne@69: 
jpayne@69: This codec de/encodes from bytes to bytes.
jpayne@69: 
jpayne@69: Written by Marc-Andre Lemburg (mal@lemburg.com). Some details were
jpayne@69: adapted from uu.py which was written by Lance Ellinghouse and
jpayne@69: modified by Jack Jansen and Fredrik Lundh.
jpayne@69: """
jpayne@69: 
jpayne@69: import codecs
jpayne@69: import binascii
jpayne@69: from io import BytesIO
jpayne@69: 
jpayne@69: ### Codec APIs
jpayne@69: 
jpayne@69: def uu_encode(input, errors='strict', filename='<data>', mode=0o666):
jpayne@69:     assert errors == 'strict'
jpayne@69:     infile = BytesIO(input)
jpayne@69:     outfile = BytesIO()
jpayne@69:     read = infile.read
jpayne@69:     write = outfile.write
jpayne@69: 
jpayne@69:     # Remove newline chars from filename
jpayne@69:     filename = filename.replace('\n','\\n')
jpayne@69:     filename = filename.replace('\r','\\r')
jpayne@69: 
jpayne@69:     # Encode
jpayne@69:     write(('begin %o %s\n' % (mode & 0o777, filename)).encode('ascii'))
jpayne@69:     chunk = read(45)
jpayne@69:     while chunk:
jpayne@69:         write(binascii.b2a_uu(chunk))
jpayne@69:         chunk = read(45)
jpayne@69:     write(b' \nend\n')
jpayne@69: 
jpayne@69:     return (outfile.getvalue(), len(input))
jpayne@69: 
jpayne@69: def uu_decode(input, errors='strict'):
jpayne@69:     assert errors == 'strict'
jpayne@69:     infile = BytesIO(input)
jpayne@69:     outfile = BytesIO()
jpayne@69:     readline = infile.readline
jpayne@69:     write = outfile.write
jpayne@69: 
jpayne@69:     # Find start of encoded data
jpayne@69:     while 1:
jpayne@69:         s = readline()
jpayne@69:         if not s:
jpayne@69:             raise ValueError('Missing "begin" line in input data')
jpayne@69:         if s[:5] == b'begin':
jpayne@69:             break
jpayne@69: 
jpayne@69:     # Decode
jpayne@69:     while True:
jpayne@69:         s = readline()
jpayne@69:         if not s or s == b'end\n':
jpayne@69:             break
jpayne@69:         try:
jpayne@69:             data = binascii.a2b_uu(s)
jpayne@69:         except binascii.Error as v:
jpayne@69:             # Workaround for broken uuencoders by /Fredrik Lundh
jpayne@69:             nbytes = (((s[0]-32) & 63) * 4 + 5) // 3
jpayne@69:             data = binascii.a2b_uu(s[:nbytes])
jpayne@69:             #sys.stderr.write("Warning: %s\n" % str(v))
jpayne@69:         write(data)
jpayne@69:     if not s:
jpayne@69:         raise ValueError('Truncated input data')
jpayne@69: 
jpayne@69:     return (outfile.getvalue(), len(input))
jpayne@69: 
jpayne@69: class Codec(codecs.Codec):
jpayne@69:     def encode(self, input, errors='strict'):
jpayne@69:         return uu_encode(input, errors)
jpayne@69: 
jpayne@69:     def decode(self, input, errors='strict'):
jpayne@69:         return uu_decode(input, errors)
jpayne@69: 
jpayne@69: class IncrementalEncoder(codecs.IncrementalEncoder):
jpayne@69:     def encode(self, input, final=False):
jpayne@69:         return uu_encode(input, self.errors)[0]
jpayne@69: 
jpayne@69: class IncrementalDecoder(codecs.IncrementalDecoder):
jpayne@69:     def decode(self, input, final=False):
jpayne@69:         return uu_decode(input, self.errors)[0]
jpayne@69: 
jpayne@69: class StreamWriter(Codec, codecs.StreamWriter):
jpayne@69:     charbuffertype = bytes
jpayne@69: 
jpayne@69: class StreamReader(Codec, codecs.StreamReader):
jpayne@69:     charbuffertype = bytes
jpayne@69: 
jpayne@69: ### encodings module API
jpayne@69: 
jpayne@69: def getregentry():
jpayne@69:     return codecs.CodecInfo(
jpayne@69:         name='uu',
jpayne@69:         encode=uu_encode,
jpayne@69:         decode=uu_decode,
jpayne@69:         incrementalencoder=IncrementalEncoder,
jpayne@69:         incrementaldecoder=IncrementalDecoder,
jpayne@69:         streamreader=StreamReader,
jpayne@69:         streamwriter=StreamWriter,
jpayne@69:         _is_text_encoding=False,
jpayne@69:     )