projects / ipfire.org.git / blame
| Commit | Line | Data |
|---|---|---|
| 43d991f6 MT |
1 | #!/usr/bin/python |
| 2 | ||
| 9068dba1 | 3 | from __future__ import division |
| 43d991f6 | 4 | |
| 170e8c36 | 5 | def ncode_hex(s): |
| f1349ebc | 6 | return s.encode("hex") |
| 43d991f6 | 7 | |
| f1349ebc MT |
8 | def decode_hex(s): |
| 9 | return s.decode("hex") | |
| 43d991f6 | 10 | |
| 43d991f6 MT |
11 | ##### This is borrowed from the bittorrent client libary ##### |
| 12 | ||
| 13 | def decode_int(x, f): | |
| 14 | f += 1 | |
| 15 | newf = x.index('e', f) | |
| 16 | n = int(x[f:newf]) | |
| 17 | if x[f] == '-': | |
| 18 | if x[f + 1] == '0': | |
| 19 | raise ValueError | |
| 20 | elif x[f] == '0' and newf != f+1: | |
| 21 | raise ValueError | |
| 22 | return (n, newf+1) | |
| 23 | ||
| 24 | def decode_string(x, f): | |
| 25 | colon = x.index(':', f) | |
| 26 | n = int(x[f:colon]) | |
| 27 | if x[f] == '0' and colon != f+1: | |
| 28 | raise ValueError | |
| 29 | colon += 1 | |
| 30 | return (x[colon:colon+n], colon+n) | |
| 31 | ||
| 32 | def decode_list(x, f): | |
| 33 | r, f = [], f+1 | |
| 34 | while x[f] != 'e': | |
| 35 | v, f = decode_func[x[f]](x, f) | |
| 36 | r.append(v) | |
| 37 | return (r, f + 1) | |
| 38 | ||
| 39 | def decode_dict(x, f): | |
| 40 | r, f = {}, f+1 | |
| 41 | while x[f] != 'e': | |
| 42 | k, f = decode_string(x, f) | |
| 43 | r[k], f = decode_func[x[f]](x, f) | |
| 44 | return (r, f + 1) | |
| 45 | ||
| 46 | decode_func = {} | |
| 47 | decode_func['l'] = decode_list | |
| 48 | decode_func['d'] = decode_dict | |
| 49 | decode_func['i'] = decode_int | |
| 50 | decode_func['0'] = decode_string | |
| 51 | decode_func['1'] = decode_string | |
| 52 | decode_func['2'] = decode_string | |
| 53 | decode_func['3'] = decode_string | |
| 54 | decode_func['4'] = decode_string | |
| 55 | decode_func['5'] = decode_string | |
| 56 | decode_func['6'] = decode_string | |
| 57 | decode_func['7'] = decode_string | |
| 58 | decode_func['8'] = decode_string | |
| 59 | decode_func['9'] = decode_string | |
| 60 | ||
| 61 | def bdecode(x): | |
| 62 | try: | |
| 63 | r, l = decode_func[x[0]](x, 0) | |
| 64 | except (IndexError, KeyError, ValueError): | |
| 65 | raise Exception("not a valid bencoded string") | |
| 66 | if l != len(x): | |
| 67 | raise Exception("invalid bencoded value (data after valid prefix)") | |
| 68 | return r | |
| 69 | ||
| 70 | from types import StringType, IntType, LongType, DictType, ListType, TupleType | |
| 71 | ||
| 72 | ||
| 73 | class Bencached(object): | |
| 74 | ||
| 75 | __slots__ = ['bencoded'] | |
| 76 | ||
| 77 | def __init__(self, s): | |
| 78 | self.bencoded = s | |
| 79 | ||
| 80 | def encode_bencached(x,r): | |
| 81 | r.append(x.bencoded) | |
| 82 | ||
| 83 | def encode_int(x, r): | |
| 84 | r.extend(('i', str(x), 'e')) | |
| 85 | ||
| 86 | def encode_bool(x, r): | |
| 87 | if x: | |
| 88 | encode_int(1, r) | |
| 89 | else: | |
| 90 | encode_int(0, r) | |
| 91 | ||
| 92 | def encode_string(x, r): | |
| 93 | r.extend((str(len(x)), ':', x)) | |
| 94 | ||
| 95 | def encode_list(x, r): | |
| 96 | r.append('l') | |
| 97 | for i in x: | |
| 98 | encode_func[type(i)](i, r) | |
| 99 | r.append('e') | |
| 100 | ||
| 101 | def encode_dict(x,r): | |
| 102 | r.append('d') | |
| 103 | ilist = x.items() | |
| 104 | ilist.sort() | |
| 105 | for k, v in ilist: | |
| 106 | r.extend((str(len(k)), ':', k)) | |
| 107 | encode_func[type(v)](v, r) | |
| 108 | r.append('e') | |
| 109 | ||
| 110 | encode_func = {} | |
| 111 | encode_func[Bencached] = encode_bencached | |
| 112 | encode_func[IntType] = encode_int | |
| 113 | encode_func[LongType] = encode_int | |
| 114 | encode_func[StringType] = encode_string | |
| 115 | encode_func[ListType] = encode_list | |
| 116 | encode_func[TupleType] = encode_list | |
| 117 | encode_func[DictType] = encode_dict | |
| 118 | ||
| 119 | try: | |
| 120 | from types import BooleanType | |
| 121 | encode_func[BooleanType] = encode_bool | |
| 122 | except ImportError: | |
| 123 | pass | |
| 124 | ||
| 125 | def bencode(x): | |
| 126 | r = [] | |
| 127 | encode_func[type(x)](x, r) | |
| 128 | return ''.join(r) |