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
|
/*
* utf8.c
*
* Copyright (c) Chris Putnam 2004-2009
*
* Source code released under the GPL
*
*/
#include <stdio.h>
#include "utf8.h"
/* UTF-8 encoding
U-00000000 - U-0000007F: 0xxxxxxx
U-00000080 - U-000007FF: 110xxxxx 10xxxxxx
U-00000800 - U-0000FFFF: 1110xxxx 10xxxxxx 10xxxxxx
U-00010000 - U-001FFFFF: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
U-00200000 - U-03FFFFFF: 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
U-04000000 - U-7FFFFFFF: 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
*/
static void
utf8_build( unsigned int value, unsigned char out[6], int in_pos, int out_pos )
{
unsigned int in_mask, out_mask;
int byte = 0;
while ( in_pos < 32 ) {
in_mask = 1 << ( 31 - in_pos );
out_mask = 1 << ( 7 - out_pos );
if ( value & in_mask ) out[byte] |= out_mask;
in_pos++;
out_pos++;
if ( out_pos > 7 ) {
out_pos=2;
byte++;
}
}
}
/* int utf8( in, out[6] );
*
* in is character code 0x0 -> 0x7FFFFFFF
* int is number of characters for output
*
*/
int
utf8_encode( unsigned int value, unsigned char out[6] )
{
int i;
for ( i=1; i<6; ++i ) out[i] = 0x80; /* 10xxxxxx */
if ( value < 0x80 ) {
out[0] = 0x0; /* 0xxxxxxx */
utf8_build( value, out, 25, 1 );
return 1;
} else if ( value < 0x800 ) {
out[0] = 0xC0; /* 110xxxxx */
utf8_build( value, out, 21, 3 );
return 2;
} else if ( value < 0x10000 ) {
out[0] = 0xE0; /* 1110xxxx */
utf8_build( value, out, 16, 4 );
return 3;
} else if ( value < 0x200000 ) {
out[0] = 0xF0; /* 11110xxx */
utf8_build( value, out, 11, 5 );
return 4;
} else if ( value < 0x4000000 ) {
out[0] = 0xF8; /* 111110xx */
utf8_build( value, out, 6, 6 );
return 5;
} else if ( value < (unsigned int ) 0x80000000 ) {
out[0] = 0xFC; /* 1111110x */
utf8_build( value, out, 1, 7 );
return 6;
} else {
/* error, above 2^31 bits encodable by UTF-8 */
return 0;
}
}
unsigned int
utf8_decode( char *s, unsigned int *pi )
{
unsigned int c;
int i = *pi;
/* one digit utf-8 */
if ((s[i] & 128)== 0 ) {
c = (unsigned int) s[i];
i += 1;
} else if ((s[i] & 224)== 192 ) { /* 110xxxxx & 111xxxxx == 110xxxxx */
c = (( (unsigned int) s[i] & 31 ) << 6) +
( (unsigned int) s[i+1] & 63 );
i += 2;
} else if ((s[i] & 240)== 224 ) { /* 1110xxxx & 1111xxxx == 1110xxxx */
c = ( ( (unsigned int) s[i] & 15 ) << 12 ) +
( ( (unsigned int) s[i+1] & 63 ) << 6 ) +
( (unsigned int) s[i+2] & 63 );
i += 3;
} else if ((s[i] & 248)== 240 ) { /* 11110xxx & 11111xxx == 11110xxx */
c = ( ( (unsigned int) s[i] & 7 ) << 18 ) +
( ( (unsigned int) s[i+1] & 63 ) << 12 ) +
( ( (unsigned int) s[i+2] & 63 ) << 6 ) +
( (unsigned int) s[i+3] & 63 );
i+= 4;
} else if ((s[i] & 252)== 248 ) { /* 111110xx & 111111xx == 111110xx */
c = ( ( (unsigned int) s[i] & 3 ) << 24 ) +
( ( (unsigned int) s[i+1] & 63 ) << 18 ) +
( ( (unsigned int) s[i+2] & 63 ) << 12 ) +
( ( (unsigned int) s[i+3] & 63 ) << 6 ) +
( (unsigned int) s[i+4] & 63 );
i += 5;
} else if ((s[i] & 254)== 252 ) { /* 1111110x & 1111111x == 1111110x */
c = ( ( (unsigned int) s[i] & 1 ) << 30 ) +
( ( (unsigned int) s[i+1] & 63 ) << 24 ) +
( ( (unsigned int) s[i+2] & 63 ) << 18 ) +
( ( (unsigned int) s[i+3] & 63 ) << 12 ) +
( ( (unsigned int) s[i+4] & 63 ) << 6 ) +
( (unsigned int) s[i+5] & 63 );
i += 6;
} else {
c = '?';
i++;
}
*pi = i;
return c;
}
void
utf8_writebom( FILE *outptr )
{
int i, nc;
unsigned char code[6];
nc = utf8_encode( 0xFEFF, code );
for ( i=0; i<nc; ++i )
fprintf(outptr,"%c",code[i]);
}
|
