xref: /illumos-gate/usr/src/lib/libc/port/locale/gb18030.c (revision e77c795bcbe51aebd7579fe13cbf2a6d56eca47f)
1 /*
2  * Copyright (c) 2002-2004 Tim J. Robbins
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
29  * Use is subject to license terms.
30  */
31 
32 /*
33  * PRC National Standard GB 18030-2000 encoding of Chinese text.
34  *
35  * See gb18030(5) for details.
36  */
37 
38 #include "lint.h"
39 #include <sys/types.h>
40 #include <errno.h>
41 #include "runetype.h"
42 #include <stdlib.h>
43 #include <string.h>
44 #include <wchar.h>
45 #include "mblocal.h"
46 
47 
48 static size_t	_GB18030_mbrtowc(wchar_t *_RESTRICT_KYWD,
49 		    const char *_RESTRICT_KYWD,
50 		    size_t, mbstate_t *_RESTRICT_KYWD);
51 static int	_GB18030_mbsinit(const mbstate_t *);
52 static size_t	_GB18030_wcrtomb(char *_RESTRICT_KYWD, wchar_t,
53 		    mbstate_t *_RESTRICT_KYWD);
54 
55 typedef struct {
56 	int	count;
57 	uchar_t	bytes[4];
58 } _GB18030State;
59 
60 int
61 _GB18030_init(_RuneLocale *rl)
62 {
63 
64 	__mbrtowc = _GB18030_mbrtowc;
65 	__wcrtomb = _GB18030_wcrtomb;
66 	__mbsinit = _GB18030_mbsinit;
67 	_CurrentRuneLocale = rl;
68 	__ctype[520] = 4;
69 	charset_is_ascii = 0;
70 
71 	return (0);
72 }
73 
74 static int
75 _GB18030_mbsinit(const mbstate_t *ps)
76 {
77 
78 	return (ps == NULL || ((const _GB18030State *)ps)->count == 0);
79 }
80 
81 static size_t
82 _GB18030_mbrtowc(wchar_t *_RESTRICT_KYWD pwc, const char *_RESTRICT_KYWD s,
83     size_t n, mbstate_t *_RESTRICT_KYWD ps)
84 {
85 	_GB18030State *gs;
86 	wchar_t wch;
87 	int ch, len, ocount;
88 	size_t ncopy;
89 
90 	gs = (_GB18030State *)ps;
91 
92 	if (gs->count < 0 || gs->count > sizeof (gs->bytes)) {
93 		errno = EINVAL;
94 		return ((size_t)-1);
95 	}
96 
97 	if (s == NULL) {
98 		s = "";
99 		n = 1;
100 		pwc = NULL;
101 	}
102 
103 	ncopy = MIN(MIN(n, MB_CUR_MAX), sizeof (gs->bytes) - gs->count);
104 	(void) memcpy(gs->bytes + gs->count, s, ncopy);
105 	ocount = gs->count;
106 	gs->count += ncopy;
107 	s = (char *)gs->bytes;
108 	n = gs->count;
109 
110 	if (n == 0)
111 		/* Incomplete multibyte sequence */
112 		return ((size_t)-2);
113 
114 	/*
115 	 * Single byte:		[00-7f]
116 	 * Two byte:		[81-fe][40-7e,80-fe]
117 	 * Four byte:		[81-fe][30-39][81-fe][30-39]
118 	 */
119 	ch = (unsigned char)*s++;
120 	if (ch <= 0x7f) {
121 		len = 1;
122 		wch = ch;
123 	} else if (ch >= 0x81 && ch <= 0xfe) {
124 		wch = ch;
125 		if (n < 2)
126 			return ((size_t)-2);
127 		ch = (unsigned char)*s++;
128 		if ((ch >= 0x40 && ch <= 0x7e) || (ch >= 0x80 && ch <= 0xfe)) {
129 			wch = (wch << 8) | ch;
130 			len = 2;
131 		} else if (ch >= 0x30 && ch <= 0x39) {
132 			/*
133 			 * Strip high bit off the wide character we will
134 			 * eventually output so that it is positive when
135 			 * cast to wint_t on 32-bit twos-complement machines.
136 			 */
137 			wch = ((wch & 0x7f) << 8) | ch;
138 			if (n < 3)
139 				return ((size_t)-2);
140 			ch = (unsigned char)*s++;
141 			if (ch < 0x81 || ch > 0xfe)
142 				goto ilseq;
143 			wch = (wch << 8) | ch;
144 			if (n < 4)
145 				return ((size_t)-2);
146 			ch = (unsigned char)*s++;
147 			if (ch < 0x30 || ch > 0x39)
148 				goto ilseq;
149 			wch = (wch << 8) | ch;
150 			len = 4;
151 		} else
152 			goto ilseq;
153 	} else
154 		goto ilseq;
155 
156 	if (pwc != NULL)
157 		*pwc = wch;
158 	gs->count = 0;
159 	return (wch == L'\0' ? 0 : len - ocount);
160 ilseq:
161 	errno = EILSEQ;
162 	return ((size_t)-1);
163 }
164 
165 static size_t
166 _GB18030_wcrtomb(char *_RESTRICT_KYWD s, wchar_t wc,
167     mbstate_t *_RESTRICT_KYWD ps)
168 {
169 	_GB18030State *gs;
170 	size_t len;
171 	int c;
172 
173 	gs = (_GB18030State *)ps;
174 
175 	if (gs->count != 0) {
176 		errno = EINVAL;
177 		return ((size_t)-1);
178 	}
179 
180 	if (s == NULL)
181 		/* Reset to initial shift state (no-op) */
182 		return (1);
183 	if ((wc & ~0x7fffffff) != 0)
184 		goto ilseq;
185 	if (wc & 0x7f000000) {
186 		/* Replace high bit that mbrtowc() removed. */
187 		wc |= 0x80000000;
188 		c = (wc >> 24) & 0xff;
189 		if (c < 0x81 || c > 0xfe)
190 			goto ilseq;
191 		*s++ = c;
192 		c = (wc >> 16) & 0xff;
193 		if (c < 0x30 || c > 0x39)
194 			goto ilseq;
195 		*s++ = c;
196 		c = (wc >> 8) & 0xff;
197 		if (c < 0x81 || c > 0xfe)
198 			goto ilseq;
199 		*s++ = c;
200 		c = wc & 0xff;
201 		if (c < 0x30 || c > 0x39)
202 			goto ilseq;
203 		*s++ = c;
204 		len = 4;
205 	} else if (wc & 0x00ff0000)
206 		goto ilseq;
207 	else if (wc & 0x0000ff00) {
208 		c = (wc >> 8) & 0xff;
209 		if (c < 0x81 || c > 0xfe)
210 			goto ilseq;
211 		*s++ = c;
212 		c = wc & 0xff;
213 		if (c < 0x40 || c == 0x7f || c == 0xff)
214 			goto ilseq;
215 		*s++ = c;
216 		len = 2;
217 	} else if (wc <= 0x7f) {
218 		*s++ = wc;
219 		len = 1;
220 	} else
221 		goto ilseq;
222 
223 	return (len);
224 ilseq:
225 	errno = EILSEQ;
226 	return ((size_t)-1);
227 }
228