big5.c revision 129166 
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)
39static 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: head/lib/libc/locale/big5.c 129166 2004-05-13 03:08:28Z tjr $");
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
51int	_BIG5_init(_RuneLocale *);
52size_t	_BIG5_mbrtowc(wchar_t * __restrict, const char * __restrict, size_t,
53	    mbstate_t * __restrict);
54int	_BIG5_mbsinit(const mbstate_t *);
55size_t	_BIG5_wcrtomb(char * __restrict, wchar_t, mbstate_t * __restrict);
56
57typedef struct {
58	int	count;
59	u_char	bytes[2];
60} _BIG5State;
61
62int
63_BIG5_init(_RuneLocale *rl)
64{
65
66	__mbrtowc = _BIG5_mbrtowc;
67	__wcrtomb = _BIG5_wcrtomb;
68	__mbsinit = _BIG5_mbsinit;
69	_CurrentRuneLocale = rl;
70	__mb_cur_max = 2;
71	return (0);
72}
73
74int
75_BIG5_mbsinit(const mbstate_t *ps)
76{
77
78	return (ps == NULL || ((const _BIG5State *)ps)->count == 0);
79}
80
81static __inline int
82_big5_check(u_int c)
83{
84
85	c &= 0xff;
86	return ((c >= 0xa1 && c <= 0xfe) ? 2 : 1);
87}
88
89size_t
90_BIG5_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
91    mbstate_t * __restrict ps)
92{
93	_BIG5State *bs;
94	wchar_t wc;
95	int i, len, ocount;
96	size_t ncopy;
97
98	bs = (_BIG5State *)ps;
99
100	if (bs->count < 0 || bs->count > sizeof(bs->bytes)) {
101		errno = EINVAL;
102		return ((size_t)-1);
103	}
104
105	if (s == NULL) {
106		s = "";
107		n = 1;
108		pwc = NULL;
109	}
110
111	ncopy = MIN(MIN(n, MB_CUR_MAX), sizeof(bs->bytes) - bs->count);
112	memcpy(bs->bytes + bs->count, s, ncopy);
113	ocount = bs->count;
114	bs->count += ncopy;
115	s = (char *)bs->bytes;
116	n = bs->count;
117
118	if (n == 0 || (size_t)(len = _big5_check(*s)) > n)
119		/* Incomplete multibyte sequence */
120		return ((size_t)-2);
121	if (len == 2 && s[1] == '\0') {
122		errno = EILSEQ;
123		return ((size_t)-1);
124	}
125	wc = 0;
126	i = len;
127	while (i-- > 0)
128		wc = (wc << 8) | (unsigned char)*s++;
129	if (pwc != NULL)
130		*pwc = wc;
131	bs->count = 0;
132	return (wc == L'\0' ? 0 : len - ocount);
133}
134
135size_t
136_BIG5_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
137{
138	_BIG5State *bs;
139
140	bs = (_BIG5State *)ps;
141
142	if (bs->count != 0) {
143		errno = EINVAL;
144		return ((size_t)-1);
145	}
146
147	if (s == NULL)
148		/* Reset to initial shift state (no-op) */
149		return (1);
150	if (wc & 0x8000) {
151		*s++ = (wc >> 8) & 0xff;
152		*s = wc & 0xff;
153		return (2);
154	}
155	*s = wc & 0xff;
156	return (1);
157}
158