1/* Access functions for JISX0212 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 _JIS0212_H
20#define _JIS0212_H 1
21
22#include <assert.h>
23#include <gconv.h>
24#include <stdint.h>
25
26
27/* Struct for table with indices in mapping table. */
28struct jisx0212_idx
29{
30 uint16_t start;
31 uint16_t end;
32 uint16_t idx;
33};
34
35/* Conversion table. */
36extern const struct jisx0212_idx __jisx0212_to_ucs_idx[];
37extern const uint16_t __jisx0212_to_ucs[];
38
39extern const struct jisx0212_idx __jisx0212_from_ucs_idx[];
40extern const char __jisx0212_from_ucs[][2];
41
42
43static inline uint32_t
44__attribute ((always_inline))
45jisx0212_to_ucs4 (const unsigned char **s, size_t avail, unsigned char offset)
46{
47 const struct jisx0212_idx *rp = __jisx0212_to_ucs_idx;
48 unsigned char ch = *(*s);
49 unsigned char ch2;
50 uint32_t wch = 0;
51 int idx;
52
53 if (ch < offset || (ch - offset) < 0x22 || (ch - offset) > 0x6d)
54 return __UNKNOWN_10646_CHAR;
55
56 if (avail < 2)
57 return 0;
58
59 ch2 = (*s)[1];
60 if (ch2 < offset || (ch2 - offset) <= 0x20 || (ch2 - offset) >= 0x7f)
61 return __UNKNOWN_10646_CHAR;
62
63 idx = (ch - offset - 0x21) * 94 + (ch2 - offset - 0x21);
64
65 while (idx > rp->end)
66 ++rp;
67 if (idx >= rp->start)
68 wch = __jisx0212_to_ucs[rp->idx + idx - rp->start];
69
70 if (wch != L'\0')
71 (*s) += 2;
72 else
73 wch = __UNKNOWN_10646_CHAR;
74
75 return wch;
76}
77
78
79static inline size_t
80__attribute ((always_inline))
81ucs4_to_jisx0212 (uint32_t wch, unsigned char *s, size_t avail)
82{
83 const struct jisx0212_idx *rp = __jisx0212_from_ucs_idx;
84 unsigned int ch = (unsigned int) wch;
85 const char *cp;
86
87 if (ch >= 0xffff)
88 return __UNKNOWN_10646_CHAR;
89 while (ch > rp->end)
90 ++rp;
91 if (ch >= rp->start)
92 cp = __jisx0212_from_ucs[rp->idx + ch - rp->start];
93 else
94 return __UNKNOWN_10646_CHAR;
95
96 if (cp[0] == '\0')
97 return __UNKNOWN_10646_CHAR;
98
99 s[0] = cp[0];
100 assert (cp[1] != '\0');
101 if (avail < 2)
102 return 0;
103
104 s[1] = cp[1];
105 return 2;
106}
107
108#endif /* jis0212.h */
109