xref: /freebsd/lib/libc/locale/gbk.c (revision 2357939bc239bd5334a169b62313806178dd8f30)
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 #include <sys/param.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <errno.h>
42 #include <runetype.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <wchar.h>
46 #include "mblocal.h"
47 
48 int	_GBK_init(_RuneLocale *);
49 size_t	_GBK_mbrtowc(wchar_t * __restrict, const char * __restrict, size_t,
50 	    mbstate_t * __restrict);
51 int	_GBK_mbsinit(const mbstate_t *);
52 size_t	_GBK_wcrtomb(char * __restrict, wchar_t, mbstate_t * __restrict);
53 
54 typedef struct {
55 	int	count;
56 	u_char	bytes[2];
57 } _GBKState;
58 
59 int
60 _GBK_init(_RuneLocale *rl)
61 {
62 
63 	__mbrtowc = _GBK_mbrtowc;
64 	__wcrtomb = _GBK_wcrtomb;
65 	__mbsinit = _GBK_mbsinit;
66 	_CurrentRuneLocale = rl;
67 	__mb_cur_max = 2;
68 	return (0);
69 }
70 
71 int
72 _GBK_mbsinit(const mbstate_t *ps)
73 {
74 
75 	return (ps == NULL || ((const _GBKState *)ps)->count == 0);
76 }
77 
78 static __inline int
79 _gbk_check(u_int c)
80 {
81 
82 	c &= 0xff;
83 	return ((c >= 0x81 && c <= 0xfe) ? 2 : 1);
84 }
85 
86 size_t
87 _GBK_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
88     mbstate_t * __restrict ps)
89 {
90 	_GBKState *gs;
91 	wchar_t wc;
92 	int i, len, ocount;
93         size_t ncopy;
94 
95 	gs = (_GBKState *)ps;
96 
97 	if (gs->count < 0 || gs->count > sizeof(gs->bytes)) {
98 		errno = EINVAL;
99 		return ((size_t)-1);
100 	}
101 
102 	if (s == NULL) {
103 		s = "";
104 		n = 1;
105 		pwc = NULL;
106 	}
107 
108 	ncopy = MIN(MIN(n, MB_CUR_MAX), sizeof(gs->bytes) - gs->count);
109 	memcpy(gs->bytes + gs->count, s, ncopy);
110 	ocount = gs->count;
111 	gs->count += ncopy;
112 	s = (char *)gs->bytes;
113 	n = gs->count;
114 
115 	if (n == 0 || (size_t)(len = _gbk_check(*s)) > n)
116 		/* Incomplete multibyte sequence */
117 		return ((size_t)-2);
118 	if (len == 2 && s[1] == '\0') {
119 		errno = EILSEQ;
120 		return ((size_t)-1);
121 	}
122 	wc = 0;
123 	i = len;
124 	while (i-- > 0)
125 		wc = (wc << 8) | (unsigned char)*s++;
126 	if (pwc != NULL)
127 		*pwc = wc;
128 	gs->count = 0;
129 	return (wc == L'\0' ? 0 : len - ocount);
130 }
131 
132 size_t
133 _GBK_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
134 {
135 	_GBKState *gs;
136 
137 	gs = (_GBKState *)ps;
138 
139 	if (gs->count != 0) {
140 		errno = EINVAL;
141 		return ((size_t)-1);
142 	}
143 
144 	if (s == NULL)
145 		/* Reset to initial shift state (no-op) */
146 		return (1);
147 	if (wc & 0x8000) {
148 		*s++ = (wc >> 8) & 0xff;
149 		*s = wc & 0xff;
150 		return (2);
151 	}
152 	*s = wc & 0xff;
153 	return (1);
154 }
155