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 * Copyright (c) 2011 The FreeBSD Foundation
10 * All rights reserved.
11 * Portions of this software were developed by David Chisnall
12 * under sponsorship from the FreeBSD Foundation.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * 1. Redistributions of source code must retain the above copyright
18 *    notice, this list of conditions and the following disclaimer.
19 * 2. Redistributions in binary form must reproduce the above copyright
20 *    notice, this list of conditions and the following disclaimer in the
21 *    documentation and/or other materials provided with the distribution.
22 * 3. All advertising materials mentioning features or use of this software
23 *    must display the following acknowledgement:
24 *	This product includes software developed by the University of
25 *	California, Berkeley and its contributors.
26 * 4. Neither the name of the University nor the names of its contributors
27 *    may be used to endorse or promote products derived from this software
28 *    without specific prior written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * SUCH DAMAGE.
41 */
42
43#if defined(LIBC_SCCS) && !defined(lint)
44static char sccsid[] = "@(#)big5.c	8.1 (Berkeley) 6/4/93";
45#endif /* LIBC_SCCS and not lint */
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD$");
48
49#include <sys/types.h>
50#include <errno.h>
51#include <runetype.h>
52#include <stdlib.h>
53#include <string.h>
54#include <wchar.h>
55#include "mblocal.h"
56
57extern int __mb_sb_limit;
58
59static size_t	_BIG5_mbrtowc(wchar_t * __restrict, const char * __restrict,
60		    size_t, mbstate_t * __restrict);
61static int	_BIG5_mbsinit(const mbstate_t *);
62static size_t	_BIG5_wcrtomb(char * __restrict, wchar_t,
63		    mbstate_t * __restrict);
64
65typedef struct {
66	wchar_t	ch;
67} _BIG5State;
68
69int
70_BIG5_init(struct xlocale_ctype *l, _RuneLocale *rl)
71{
72
73	l->__mbrtowc = _BIG5_mbrtowc;
74	l->__wcrtomb = _BIG5_wcrtomb;
75	l->__mbsinit = _BIG5_mbsinit;
76	l->runes = rl;
77	l->__mb_cur_max = 2;
78	l->__mb_sb_limit = 128;
79	return (0);
80}
81
82static int
83_BIG5_mbsinit(const mbstate_t *ps)
84{
85
86	return (ps == NULL || ((const _BIG5State *)ps)->ch == 0);
87}
88
89static __inline int
90_big5_check(u_int c)
91{
92
93	c &= 0xff;
94	return ((c >= 0xa1 && c <= 0xfe) ? 2 : 1);
95}
96
97static size_t
98_BIG5_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
99    mbstate_t * __restrict ps)
100{
101	_BIG5State *bs;
102	wchar_t wc;
103	size_t len;
104
105	bs = (_BIG5State *)ps;
106
107	if ((bs->ch & ~0xFF) != 0) {
108		/* Bad conversion state. */
109		errno = EINVAL;
110		return ((size_t)-1);
111	}
112
113	if (s == NULL) {
114		s = "";
115		n = 1;
116		pwc = NULL;
117	}
118
119	if (n == 0)
120		/* Incomplete multibyte sequence */
121		return ((size_t)-2);
122
123	if (bs->ch != 0) {
124		if (*s == '\0') {
125			errno = EILSEQ;
126			return ((size_t)-1);
127		}
128		wc = (bs->ch << 8) | (*s & 0xFF);
129		if (pwc != NULL)
130			*pwc = wc;
131		bs->ch = 0;
132		return (1);
133	}
134
135	len = (size_t)_big5_check(*s);
136	wc = *s++ & 0xff;
137	if (len == 2) {
138		if (n < 2) {
139			/* Incomplete multibyte sequence */
140			bs->ch = wc;
141			return ((size_t)-2);
142		}
143		if (*s == '\0') {
144			errno = EILSEQ;
145			return ((size_t)-1);
146		}
147		wc = (wc << 8) | (*s++ & 0xff);
148		if (pwc != NULL)
149			*pwc = wc;
150                return (2);
151	} else {
152		if (pwc != NULL)
153			*pwc = wc;
154		return (wc == L'\0' ? 0 : 1);
155	}
156}
157
158static size_t
159_BIG5_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
160{
161	_BIG5State *bs;
162
163	bs = (_BIG5State *)ps;
164
165	if (bs->ch != 0) {
166		errno = EINVAL;
167		return ((size_t)-1);
168	}
169
170	if (s == NULL)
171		/* Reset to initial shift state (no-op) */
172		return (1);
173	if (wc & 0x8000) {
174		*s++ = (wc >> 8) & 0xff;
175		*s = wc & 0xff;
176		return (2);
177	}
178	*s = wc & 0xff;
179	return (1);
180}
181