blob: 7ee637f80ba200a0e81c24d050793b765e45d29c (
plain)
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
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/*
* Character Set Handling
* (C) 1999-2007 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/
#include <botan/charset.h>
#include <botan/parsing.h>
#include <botan/exceptn.h>
#include <cctype>
namespace Botan {
namespace Charset {
namespace {
/*
* Convert from UCS-2 to ISO 8859-1
*/
std::string ucs2_to_latin1(const std::string& ucs2)
{
if(ucs2.size() % 2 == 1)
throw Decoding_Error("UCS-2 string has an odd number of bytes");
std::string latin1;
for(size_t i = 0; i != ucs2.size(); i += 2)
{
const byte c1 = ucs2[i];
const byte c2 = ucs2[i+1];
if(c1 != 0)
throw Decoding_Error("UCS-2 has non-Latin1 characters");
latin1 += static_cast<char>(c2);
}
return latin1;
}
/*
* Convert from UTF-8 to ISO 8859-1
*/
std::string utf8_to_latin1(const std::string& utf8)
{
std::string iso8859;
size_t position = 0;
while(position != utf8.size())
{
const byte c1 = static_cast<byte>(utf8[position++]);
if(c1 <= 0x7F)
iso8859 += static_cast<char>(c1);
else if(c1 >= 0xC0 && c1 <= 0xC7)
{
if(position == utf8.size())
throw Decoding_Error("UTF-8: sequence truncated");
const byte c2 = static_cast<byte>(utf8[position++]);
const byte iso_char = ((c1 & 0x07) << 6) | (c2 & 0x3F);
if(iso_char <= 0x7F)
throw Decoding_Error("UTF-8: sequence longer than needed");
iso8859 += static_cast<char>(iso_char);
}
else
throw Decoding_Error("UTF-8: Unicode chars not in Latin1 used");
}
return iso8859;
}
/*
* Convert from ISO 8859-1 to UTF-8
*/
std::string latin1_to_utf8(const std::string& iso8859)
{
std::string utf8;
for(size_t i = 0; i != iso8859.size(); ++i)
{
const byte c = static_cast<byte>(iso8859[i]);
if(c <= 0x7F)
utf8 += static_cast<char>(c);
else
{
utf8 += static_cast<char>((0xC0 | (c >> 6)));
utf8 += static_cast<char>((0x80 | (c & 0x3F)));
}
}
return utf8;
}
}
/*
* Perform character set transcoding
*/
std::string transcode(const std::string& str,
Character_Set to, Character_Set from)
{
if(to == LOCAL_CHARSET)
to = LATIN1_CHARSET;
if(from == LOCAL_CHARSET)
from = LATIN1_CHARSET;
if(to == from)
return str;
if(from == LATIN1_CHARSET && to == UTF8_CHARSET)
return latin1_to_utf8(str);
if(from == UTF8_CHARSET && to == LATIN1_CHARSET)
return utf8_to_latin1(str);
if(from == UCS2_CHARSET && to == LATIN1_CHARSET)
return ucs2_to_latin1(str);
throw Invalid_Argument("Unknown transcoding operation from " +
std::to_string(from) + " to " + std::to_string(to));
}
/*
* Check if a character represents a digit
*/
bool is_digit(char c)
{
if(c == '0' || c == '1' || c == '2' || c == '3' || c == '4' ||
c == '5' || c == '6' || c == '7' || c == '8' || c == '9')
return true;
return false;
}
/*
* Check if a character represents whitespace
*/
bool is_space(char c)
{
if(c == ' ' || c == '\t' || c == '\n' || c == '\r')
return true;
return false;
}
/*
* Convert a character to a digit
*/
byte char2digit(char c)
{
switch(c)
{
case '0': return 0;
case '1': return 1;
case '2': return 2;
case '3': return 3;
case '4': return 4;
case '5': return 5;
case '6': return 6;
case '7': return 7;
case '8': return 8;
case '9': return 9;
}
throw Invalid_Argument("char2digit: Input is not a digit character");
}
/*
* Convert a digit to a character
*/
char digit2char(byte b)
{
switch(b)
{
case 0: return '0';
case 1: return '1';
case 2: return '2';
case 3: return '3';
case 4: return '4';
case 5: return '5';
case 6: return '6';
case 7: return '7';
case 8: return '8';
case 9: return '9';
}
throw Invalid_Argument("digit2char: Input is not a digit");
}
/*
* Case-insensitive character comparison
*/
bool caseless_cmp(char a, char b)
{
return (std::tolower(static_cast<unsigned char>(a)) ==
std::tolower(static_cast<unsigned char>(b)));
}
}
}
|
