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1 /*
2 * Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
3 *
4 * Permission is hereby granted, free of charge, to any person
5 * obtaining a copy of this software and associated documentation
6 * files (the "Software"), to deal in the Software without
7 * restriction, including without limitation the rights to use, copy,
8 * modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
25 #include "gmid.h"
27 #include <stddef.h>
28 #include <stdint.h>
30 #define UTF8_ACCEPT 0
31 #define UTF8_REJECT 1
33 static const uint8_t utf8d[] = {
34 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 00..1f
35 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 20..3f
36 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 40..5f
37 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, // 60..7f
38 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9, // 80..9f
39 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, // a0..bf
40 8,8,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2, // c0..df
41 0xa,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x3,0x4,0x3,0x3, // e0..ef
42 0xb,0x6,0x6,0x6,0x5,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8,0x8, // f0..ff
43 0x0,0x1,0x2,0x3,0x5,0x8,0x7,0x1,0x1,0x1,0x4,0x6,0x1,0x1,0x1,0x1, // s0..s0
44 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,1,0,1,0,1,1,1,1,1,1, // s1..s2
45 1,2,1,1,1,1,1,2,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1, // s3..s4
46 1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,3,1,3,1,1,1,1,1,1, // s5..s6
47 1,3,1,1,1,1,1,3,1,3,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1,1,1,1,1,1, // s7..s8
48 };
50 static inline uint32_t
51 utf8_decode(uint32_t* state, uint32_t* codep, uint8_t byte) {
52 uint32_t type = utf8d[byte];
54 *codep = (*state != UTF8_ACCEPT) ?
55 (byte & 0x3fu) | (*codep << 6) :
56 (0xff >> type) & (byte);
58 *state = utf8d[256 + *state*16 + type];
59 return *state;
60 }
62 /* for the iri parser. Modelled after printCodePoints */
63 int
64 valid_multibyte_utf8(struct parser *p)
65 {
66 uint32_t cp = 0, state = 0;
68 for (; *p->iri; p->iri++)
69 if (!utf8_decode(&state, &cp, *p->iri))
70 break;
72 /* reject the ASCII range */
73 if (state || cp <= 0x7F) {
74 /* XXX: do some error recovery? */
75 if (state)
76 p->err = "invalid UTF-8 character";
77 return 0;
78 }
79 return 1;
80 }
82 char *
83 utf8_nth(char *s, size_t n)
84 {
85 size_t i;
86 uint32_t cp = 0, state = 0;
88 for (i = 0; *s && i < n; ++s)
89 if (!utf8_decode(&state, &cp, *s))
90 ++i;
92 if (state != UTF8_ACCEPT)
93 return NULL;
94 if (i == n)
95 return s;
96 return NULL;
97 }