1/*-
2 * Copyright 2013 Garrett D'Amore <garrett@damore.org>
3 * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
4 * Copyright (c) 2002-2004 Tim J. Robbins
5 * All rights reserved.
6 *
7 * Copyright (c) 2011 The FreeBSD Foundation
8 * All rights reserved.
9 * Portions of this software were developed by David Chisnall
10 * under sponsorship from the FreeBSD Foundation.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 *    notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34/*
35 * PRC National Standard GB 18030-2000 encoding of Chinese text.
36 *
37 * See gb18030(5) for details.
38 */
39
40#include <sys/param.h>
41__FBSDID("$FreeBSD$");
42
43#include <errno.h>
44#include <runetype.h>
45#include <stdlib.h>
46#include <string.h>
47#include <wchar.h>
48#include "mblocal.h"
49
50static size_t	_GB18030_mbrtowc(wchar_t * __restrict, const char * __restrict,
51		    size_t, mbstate_t * __restrict);
52static int	_GB18030_mbsinit(const mbstate_t *);
53static size_t	_GB18030_wcrtomb(char * __restrict, wchar_t,
54		    mbstate_t * __restrict);
55static size_t	_GB18030_mbsnrtowcs(wchar_t * __restrict,
56		    const char ** __restrict, size_t, size_t,
57		    mbstate_t * __restrict);
58static size_t	_GB18030_wcsnrtombs(char * __restrict,
59		    const wchar_t ** __restrict, size_t, size_t,
60		    mbstate_t * __restrict);
61
62
63typedef struct {
64	int	count;
65	u_char	bytes[4];
66} _GB18030State;
67
68int
69_GB18030_init(struct xlocale_ctype *l, _RuneLocale *rl)
70{
71
72	l->__mbrtowc = _GB18030_mbrtowc;
73	l->__wcrtomb = _GB18030_wcrtomb;
74	l->__mbsinit = _GB18030_mbsinit;
75	l->__mbsnrtowcs = _GB18030_mbsnrtowcs;
76	l->__wcsnrtombs = _GB18030_wcsnrtombs;
77	l->runes = rl;
78	l->__mb_cur_max = 4;
79	l->__mb_sb_limit = 128;
80
81	return (0);
82}
83
84static int
85_GB18030_mbsinit(const mbstate_t *ps)
86{
87
88	return (ps == NULL || ((const _GB18030State *)ps)->count == 0);
89}
90
91static size_t
92_GB18030_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s,
93    size_t n, mbstate_t * __restrict ps)
94{
95	_GB18030State *gs;
96	wchar_t wch;
97	int ch, len, ocount;
98	size_t ncopy;
99
100	gs = (_GB18030State *)ps;
101
102	if (gs->count < 0 || gs->count > sizeof(gs->bytes)) {
103		errno = EINVAL;
104		return ((size_t)-1);
105	}
106
107	if (s == NULL) {
108		s = "";
109		n = 1;
110		pwc = NULL;
111	}
112
113	ncopy = MIN(MIN(n, MB_CUR_MAX), sizeof(gs->bytes) - gs->count);
114	memcpy(gs->bytes + gs->count, s, ncopy);
115	ocount = gs->count;
116	gs->count += ncopy;
117	s = (char *)gs->bytes;
118	n = gs->count;
119
120	if (n == 0)
121		/* Incomplete multibyte sequence */
122		return ((size_t)-2);
123
124	/*
125	 * Single byte:		[00-7f]
126	 * Two byte:		[81-fe][40-7e,80-fe]
127	 * Four byte:		[81-fe][30-39][81-fe][30-39]
128	 */
129	ch = (unsigned char)*s++;
130	if (ch <= 0x7f) {
131		len = 1;
132		wch = ch;
133	} else if (ch >= 0x81 && ch <= 0xfe) {
134		wch = ch;
135		if (n < 2)
136			return ((size_t)-2);
137		ch = (unsigned char)*s++;
138		if ((ch >= 0x40 && ch <= 0x7e) || (ch >= 0x80 && ch <= 0xfe)) {
139			wch = (wch << 8) | ch;
140			len = 2;
141		} else if (ch >= 0x30 && ch <= 0x39) {
142			/*
143			 * Strip high bit off the wide character we will
144			 * eventually output so that it is positive when
145			 * cast to wint_t on 32-bit twos-complement machines.
146			 */
147			wch = ((wch & 0x7f) << 8) | ch;
148			if (n < 3)
149				return ((size_t)-2);
150			ch = (unsigned char)*s++;
151			if (ch < 0x81 || ch > 0xfe)
152				goto ilseq;
153			wch = (wch << 8) | ch;
154			if (n < 4)
155				return ((size_t)-2);
156			ch = (unsigned char)*s++;
157			if (ch < 0x30 || ch > 0x39)
158				goto ilseq;
159			wch = (wch << 8) | ch;
160			len = 4;
161		} else
162			goto ilseq;
163	} else
164		goto ilseq;
165
166	if (pwc != NULL)
167		*pwc = wch;
168	gs->count = 0;
169	return (wch == L'\0' ? 0 : len - ocount);
170ilseq:
171	errno = EILSEQ;
172	return ((size_t)-1);
173}
174
175static size_t
176_GB18030_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
177{
178	_GB18030State *gs;
179	size_t len;
180	int c;
181
182	gs = (_GB18030State *)ps;
183
184	if (gs->count != 0) {
185		errno = EINVAL;
186		return ((size_t)-1);
187	}
188
189	if (s == NULL)
190		/* Reset to initial shift state (no-op) */
191		return (1);
192	if ((wc & ~0x7fffffff) != 0)
193		goto ilseq;
194	if (wc & 0x7f000000) {
195		/* Replace high bit that mbrtowc() removed. */
196		wc |= 0x80000000;
197		c = (wc >> 24) & 0xff;
198		if (c < 0x81 || c > 0xfe)
199			goto ilseq;
200		*s++ = c;
201		c = (wc >> 16) & 0xff;
202		if (c < 0x30 || c > 0x39)
203			goto ilseq;
204		*s++ = c;
205		c = (wc >> 8) & 0xff;
206		if (c < 0x81 || c > 0xfe)
207			goto ilseq;
208		*s++ = c;
209		c = wc & 0xff;
210		if (c < 0x30 || c > 0x39)
211			goto ilseq;
212		*s++ = c;
213		len = 4;
214	} else if (wc & 0x00ff0000)
215		goto ilseq;
216	else if (wc & 0x0000ff00) {
217		c = (wc >> 8) & 0xff;
218		if (c < 0x81 || c > 0xfe)
219			goto ilseq;
220		*s++ = c;
221		c = wc & 0xff;
222		if (c < 0x40 || c == 0x7f || c == 0xff)
223			goto ilseq;
224		*s++ = c;
225		len = 2;
226	} else if (wc <= 0x7f) {
227		*s++ = wc;
228		len = 1;
229	} else
230		goto ilseq;
231
232	return (len);
233ilseq:
234	errno = EILSEQ;
235	return ((size_t)-1);
236}
237
238static size_t
239_GB18030_mbsnrtowcs(wchar_t * __restrict dst,
240    const char ** __restrict src, size_t nms, size_t len,
241    mbstate_t * __restrict ps)
242{
243	return (__mbsnrtowcs_std(dst, src, nms, len, ps, _GB18030_mbrtowc));
244}
245
246static size_t
247_GB18030_wcsnrtombs(char * __restrict dst,
248    const wchar_t ** __restrict src, size_t nwc, size_t len,
249    mbstate_t * __restrict ps)
250{
251	return (__wcsnrtombs_std(dst, src, nwc, len, ps, _GB18030_wcrtomb));
252}
253