xref: /freebsd/lib/libc/locale/big5.c (revision 2546665afcaf0d53dc2c7058fee96354b3680f5a)
1 /*-
2  * Copyright (c) 2002-2004 Tim J. Robbins. All rights reserved.
3  * Copyright (c) 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Paul Borman at Krystal Technologies.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by the University of
20  *	California, Berkeley and its contributors.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 #if defined(LIBC_SCCS) && !defined(lint)
39 static char sccsid[] = "@(#)big5.c	8.1 (Berkeley) 6/4/93";
40 #endif /* LIBC_SCCS and not lint */
41 #include <sys/param.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <errno.h>
45 #include <runetype.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <wchar.h>
49 #include "mblocal.h"
50 
51 int	_BIG5_init(_RuneLocale *);
52 size_t	_BIG5_mbrtowc(wchar_t * __restrict, const char * __restrict, size_t,
53 	    mbstate_t * __restrict);
54 int	_BIG5_mbsinit(const mbstate_t *);
55 size_t	_BIG5_wcrtomb(char * __restrict, wchar_t, mbstate_t * __restrict);
56 
57 typedef struct {
58 	wchar_t	ch;
59 } _BIG5State;
60 
61 int
62 _BIG5_init(_RuneLocale *rl)
63 {
64 
65 	__mbrtowc = _BIG5_mbrtowc;
66 	__wcrtomb = _BIG5_wcrtomb;
67 	__mbsinit = _BIG5_mbsinit;
68 	_CurrentRuneLocale = rl;
69 	__mb_cur_max = 2;
70 	return (0);
71 }
72 
73 int
74 _BIG5_mbsinit(const mbstate_t *ps)
75 {
76 
77 	return (ps == NULL || ((const _BIG5State *)ps)->ch == 0);
78 }
79 
80 static __inline int
81 _big5_check(u_int c)
82 {
83 
84 	c &= 0xff;
85 	return ((c >= 0xa1 && c <= 0xfe) ? 2 : 1);
86 }
87 
88 size_t
89 _BIG5_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
90     mbstate_t * __restrict ps)
91 {
92 	_BIG5State *bs;
93 	wchar_t wc;
94 	size_t len;
95 
96 	bs = (_BIG5State *)ps;
97 
98 	if ((bs->ch & ~0xFF) != 0) {
99 		/* Bad conversion state. */
100 		errno = EINVAL;
101 		return ((size_t)-1);
102 	}
103 
104 	if (s == NULL) {
105 		s = "";
106 		n = 1;
107 		pwc = NULL;
108 	}
109 
110 	if (n == 0)
111 		/* Incomplete multibyte sequence */
112 		return ((size_t)-2);
113 
114 	if (bs->ch != 0) {
115 		if (*s == '\0') {
116 			errno = EILSEQ;
117 			return ((size_t)-1);
118 		}
119 		wc = (bs->ch << 8) | (*s & 0xFF);
120 		if (pwc != NULL)
121 			*pwc = wc;
122 		bs->ch = 0;
123 		return (1);
124 	}
125 
126 	len = (size_t)_big5_check(*s);
127 	wc = *s++ & 0xff;
128 	if (len == 2) {
129 		if (n < 2) {
130 			/* Incomplete multibyte sequence */
131 			bs->ch = wc;
132 			return ((size_t)-2);
133 		}
134 		if (*s == '\0') {
135 			errno = EILSEQ;
136 			return ((size_t)-1);
137 		}
138 		wc = (wc << 8) | (*s++ & 0xff);
139 		if (pwc != NULL)
140 			*pwc = wc;
141                 return (2);
142 	} else {
143 		if (pwc != NULL)
144 			*pwc = wc;
145 		return (wc == L'\0' ? 0 : 1);
146 	}
147 }
148 
149 size_t
150 _BIG5_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
151 {
152 	_BIG5State *bs;
153 
154 	bs = (_BIG5State *)ps;
155 
156 	if (bs->ch != 0) {
157 		errno = EINVAL;
158 		return ((size_t)-1);
159 	}
160 
161 	if (s == NULL)
162 		/* Reset to initial shift state (no-op) */
163 		return (1);
164 	if (wc & 0x8000) {
165 		*s++ = (wc >> 8) & 0xff;
166 		*s = wc & 0xff;
167 		return (2);
168 	}
169 	*s = wc & 0xff;
170 	return (1);
171 }
172