big5.c revision 172619 
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/cdefs.h>
42__FBSDID("$FreeBSD: head/lib/libc/locale/big5.c 172619 2007-10-13 16:28:22Z ache $");
43
44#include <sys/types.h>
45#include <errno.h>
46#include <runetype.h>
47#include <stdlib.h>
48#include <string.h>
49#include <wchar.h>
50#include "mblocal.h"
51
52extern int __mb_sb_limit;
53
54static size_t	_BIG5_mbrtowc(wchar_t * __restrict, const char * __restrict,
55		    size_t, mbstate_t * __restrict);
56static int	_BIG5_mbsinit(const mbstate_t *);
57static size_t	_BIG5_wcrtomb(char * __restrict, wchar_t,
58		    mbstate_t * __restrict);
59
60typedef struct {
61	wchar_t	ch;
62} _BIG5State;
63
64int
65_BIG5_init(_RuneLocale *rl)
66{
67
68	__mbrtowc = _BIG5_mbrtowc;
69	__wcrtomb = _BIG5_wcrtomb;
70	__mbsinit = _BIG5_mbsinit;
71	_CurrentRuneLocale = rl;
72	__mb_cur_max = 2;
73	__mb_sb_limit = 128;
74	return (0);
75}
76
77static int
78_BIG5_mbsinit(const mbstate_t *ps)
79{
80
81	return (ps == NULL || ((const _BIG5State *)ps)->ch == 0);
82}
83
84static __inline int
85_big5_check(u_int c)
86{
87
88	c &= 0xff;
89	return ((c >= 0xa1 && c <= 0xfe) ? 2 : 1);
90}
91
92static size_t
93_BIG5_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
94    mbstate_t * __restrict ps)
95{
96	_BIG5State *bs;
97	wchar_t wc;
98	size_t len;
99
100	bs = (_BIG5State *)ps;
101
102	if ((bs->ch & ~0xFF) != 0) {
103		/* Bad conversion state. */
104		errno = EINVAL;
105		return ((size_t)-1);
106	}
107
108	if (s == NULL) {
109		s = "";
110		n = 1;
111		pwc = NULL;
112	}
113
114	if (n == 0)
115		/* Incomplete multibyte sequence */
116		return ((size_t)-2);
117
118	if (bs->ch != 0) {
119		if (*s == '\0') {
120			errno = EILSEQ;
121			return ((size_t)-1);
122		}
123		wc = (bs->ch << 8) | (*s & 0xFF);
124		if (pwc != NULL)
125			*pwc = wc;
126		bs->ch = 0;
127		return (1);
128	}
129
130	len = (size_t)_big5_check(*s);
131	wc = *s++ & 0xff;
132	if (len == 2) {
133		if (n < 2) {
134			/* Incomplete multibyte sequence */
135			bs->ch = wc;
136			return ((size_t)-2);
137		}
138		if (*s == '\0') {
139			errno = EILSEQ;
140			return ((size_t)-1);
141		}
142		wc = (wc << 8) | (*s++ & 0xff);
143		if (pwc != NULL)
144			*pwc = wc;
145                return (2);
146	} else {
147		if (pwc != NULL)
148			*pwc = wc;
149		return (wc == L'\0' ? 0 : 1);
150	}
151}
152
153static size_t
154_BIG5_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
155{
156	_BIG5State *bs;
157
158	bs = (_BIG5State *)ps;
159
160	if (bs->ch != 0) {
161		errno = EINVAL;
162		return ((size_t)-1);
163	}
164
165	if (s == NULL)
166		/* Reset to initial shift state (no-op) */
167		return (1);
168	if (wc & 0x8000) {
169		*s++ = (wc >> 8) & 0xff;
170		*s = wc & 0xff;
171		return (2);
172	}
173	*s = wc & 0xff;
174	return (1);
175}
176