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# bencode structured encoding
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# Written by Petru Paler
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# Permission is hereby granted, free of charge, to any person
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# obtaining a copy of this software and associated documentation files
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# (the "Software"), to deal in the Software without restriction,
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# including without limitation the rights to use, copy, modify, merge,
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# publish, distribute, sublicense, and/or sell copies of the Software,
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# and to permit persons to whom the Software is furnished to do so,
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# subject to the following conditions:
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# The above copyright notice and this permission notice shall be
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# included in all copies or substantial portions of the Software.
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# Modifications copyright (C) 2008 Canonical Ltd
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class BDecoder(object):
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def __init__(self, yield_tuples=False):
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:param yield_tuples: if true, decode "l" elements as tuples rather than
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self.yield_tuples = yield_tuples
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decode_func['l'] = self.decode_list
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decode_func['d'] = self.decode_dict
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decode_func['i'] = self.decode_int
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decode_func['0'] = self.decode_string
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decode_func['1'] = self.decode_string
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decode_func['2'] = self.decode_string
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decode_func['3'] = self.decode_string
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decode_func['4'] = self.decode_string
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decode_func['5'] = self.decode_string
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decode_func['6'] = self.decode_string
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decode_func['7'] = self.decode_string
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decode_func['8'] = self.decode_string
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decode_func['9'] = self.decode_string
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self.decode_func = decode_func
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def decode_int(self, x, f):
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newf = x.index('e', f)
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except (OverflowError, ValueError):
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elif x[f] == '0' and newf != f+1:
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def decode_string(self, x, f):
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colon = x.index(':', f)
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except (OverflowError, ValueError):
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if x[f] == '0' and colon != f+1:
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return (x[colon:colon+n], colon+n)
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def decode_list(self, x, f):
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v, f = self.decode_func[x[f]](x, f)
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def decode_dict(self, x, f):
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k, f = self.decode_string(x, f)
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r[k], f = self.decode_func[x[f]](x, f)
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r, l = self.decode_func[x[0]](x, 0)
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except (IndexError, KeyError):
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bdecode = _decoder.bdecode
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_tuple_decoder = BDecoder(True)
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bdecode_as_tuple = _tuple_decoder.bdecode
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from types import StringType, IntType, LongType, DictType, ListType, TupleType
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class Bencached(object):
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__slots__ = ['bencoded']
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def __init__(self, s):
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def encode_bencached(x,r):
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def encode_int(x, r):
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r.extend(('i', str(x), 'e'))
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def encode_string(x, r):
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r.extend((str(len(x)), ':', x))
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def encode_list(x, r):
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encode_func[type(i)](i, r)
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def encode_dict(x,r):
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r.extend((str(len(k)), ':', k))
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encode_func[type(v)](v, r)
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encode_func[type(Bencached(0))] = encode_bencached
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encode_func[IntType] = encode_int
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encode_func[LongType] = encode_int
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encode_func[StringType] = encode_string
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encode_func[ListType] = encode_list
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encode_func[TupleType] = encode_list
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encode_func[DictType] = encode_dict
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from types import BooleanType
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def encode_bool(x,r):
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encode_int(int(x), r)
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encode_func[BooleanType] = encode_bool
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encode_func[type(x)](x, r)