1/* Access functions for JISX0208 conversion.
2 Copyright (C) 1997-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19#ifndef _JIS0208_H
20#define _JIS0208_H 1
21
22#include <gconv.h>
23#include <stdint.h>
24
25/* Struct for table with indices in UCS mapping table. */
26struct jisx0208_ucs_idx
27{
28 uint16_t start;
29 uint16_t end;
30 uint16_t idx;
31};
32
33
34/* Conversion table. */
35extern const uint16_t __jis0208_to_ucs[];
36
37#define JIS0208_LAT1_MIN 0xa2
38#define JIS0208_LAT1_MAX 0xf7
39extern const char __jisx0208_from_ucs4_lat1[JIS0208_LAT1_MAX + 1
40 - JIS0208_LAT1_MIN][2];
41extern const char __jisx0208_from_ucs4_greek[0xc1][2];
42extern const struct jisx0208_ucs_idx __jisx0208_from_ucs_idx[];
43extern const char __jisx0208_from_ucs_tab[][2];
44
45
46static inline uint32_t
47__attribute ((always_inline))
48jisx0208_to_ucs4 (const unsigned char **s, size_t avail, unsigned char offset)
49{
50 unsigned char ch = *(*s);
51 unsigned char ch2;
52 int idx;
53
54 if (ch < offset || (ch - offset) <= 0x20)
55 return __UNKNOWN_10646_CHAR;
56
57 if (avail < 2)
58 return 0;
59
60 ch2 = (*s)[1];
61 if (ch2 < offset || (ch2 - offset) <= 0x20 || (ch2 - offset) >= 0x7f)
62 return __UNKNOWN_10646_CHAR;
63
64 idx = (ch - 0x21 - offset) * 94 + (ch2 - 0x21 - offset);
65 if (idx >= 0x1e80)
66 return __UNKNOWN_10646_CHAR;
67
68 (*s) += 2;
69
70 return __jis0208_to_ucs[idx] ?: ((*s) -= 2, __UNKNOWN_10646_CHAR);
71}
72
73
74static inline size_t
75__attribute ((always_inline))
76ucs4_to_jisx0208 (uint32_t wch, unsigned char *s, size_t avail)
77{
78 unsigned int ch = (unsigned int) wch;
79 const char *cp;
80
81 if (avail < 2)
82 return 0;
83
84 if (ch >= JIS0208_LAT1_MIN && ch <= JIS0208_LAT1_MAX)
85 cp = __jisx0208_from_ucs4_lat1[ch - JIS0208_LAT1_MIN];
86 else if (ch >= 0x391 && ch <= 0x451)
87 cp = __jisx0208_from_ucs4_greek[ch - 0x391];
88 else
89 {
90 const struct jisx0208_ucs_idx *rp = __jisx0208_from_ucs_idx;
91
92 if (ch >= 0xffff)
93 return __UNKNOWN_10646_CHAR;
94 while (ch > rp->end)
95 ++rp;
96 if (ch >= rp->start)
97 cp = __jisx0208_from_ucs_tab[rp->idx + ch - rp->start];
98 else
99 return __UNKNOWN_10646_CHAR;
100 }
101
102 if (cp[0] == '\0')
103 return __UNKNOWN_10646_CHAR;
104
105 s[0] = cp[0];
106 s[1] = cp[1];
107
108 return 2;
109}
110
111#endif /* jis0208.h */
112