1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
|
#!/usr/bin/env python
""" Python Character Mapping Codec for ROT13.
See http://ucsub.colorado.edu/~kominek/rot13/ for details.
Written by Marc-Andre Lemburg (mal@lemburg.com).
"""#"
import codecs
### Codec APIs
class Codec(codecs.Codec):
def encode(self,input,errors='strict'):
return codecs.charmap_encode(input,errors,encoding_map)
def decode(self,input,errors='strict'):
return codecs.charmap_decode(input,errors,decoding_map)
class IncrementalEncoder(codecs.IncrementalEncoder):
def encode(self, input, final=False):
return codecs.charmap_encode(input,self.errors,encoding_map)[0]
class IncrementalDecoder(codecs.IncrementalDecoder):
def decode(self, input, final=False):
return codecs.charmap_decode(input,self.errors,decoding_map)[0]
class StreamWriter(Codec,codecs.StreamWriter):
pass
class StreamReader(Codec,codecs.StreamReader):
pass
### encodings module API
def getregentry():
return codecs.CodecInfo(
name='rot-13',
encode=Codec().encode,
decode=Codec().decode,
incrementalencoder=IncrementalEncoder,
incrementaldecoder=IncrementalDecoder,
streamwriter=StreamWriter,
streamreader=StreamReader,
_is_text_encoding=False,
)
### Decoding Map
decoding_map = codecs.make_identity_dict(range(256))
decoding_map.update({
0x0041: 0x004e,
0x0042: 0x004f,
0x0043: 0x0050,
0x0044: 0x0051,
0x0045: 0x0052,
0x0046: 0x0053,
0x0047: 0x0054,
0x0048: 0x0055,
0x0049: 0x0056,
0x004a: 0x0057,
0x004b: 0x0058,
0x004c: 0x0059,
0x004d: 0x005a,
0x004e: 0x0041,
0x004f: 0x0042,
0x0050: 0x0043,
0x0051: 0x0044,
0x0052: 0x0045,
0x0053: 0x0046,
0x0054: 0x0047,
0x0055: 0x0048,
0x0056: 0x0049,
0x0057: 0x004a,
0x0058: 0x004b,
0x0059: 0x004c,
0x005a: 0x004d,
0x0061: 0x006e,
0x0062: 0x006f,
0x0063: 0x0070,
0x0064: 0x0071,
0x0065: 0x0072,
0x0066: 0x0073,
0x0067: 0x0074,
0x0068: 0x0075,
0x0069: 0x0076,
0x006a: 0x0077,
0x006b: 0x0078,
0x006c: 0x0079,
0x006d: 0x007a,
0x006e: 0x0061,
0x006f: 0x0062,
0x0070: 0x0063,
0x0071: 0x0064,
0x0072: 0x0065,
0x0073: 0x0066,
0x0074: 0x0067,
0x0075: 0x0068,
0x0076: 0x0069,
0x0077: 0x006a,
0x0078: 0x006b,
0x0079: 0x006c,
0x007a: 0x006d,
})
### Encoding Map
encoding_map = codecs.make_encoding_map(decoding_map)
### Filter API
def rot13(infile, outfile):
outfile.write(infile.read().encode('rot-13'))
if __name__ == '__main__':
import sys
rot13(sys.stdin, sys.stdout)
|
