xref: /freebsd/lib/libc/locale/gbk.c (revision 195ebc7e9e4b129de810833791a19dfb4349d6a9)
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  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/types.h>
38 #include <errno.h>
39 #include <runetype.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <wchar.h>
43 #include "mblocal.h"
44 
45 extern int __mb_sb_limit;
46 
47 static size_t	_GBK_mbrtowc(wchar_t * __restrict, const char * __restrict,
48 		    size_t, mbstate_t * __restrict);
49 static int	_GBK_mbsinit(const mbstate_t *);
50 static size_t	_GBK_wcrtomb(char * __restrict, wchar_t,
51 		    mbstate_t * __restrict);
52 
53 typedef struct {
54 	wchar_t	ch;
55 } _GBKState;
56 
57 int
58 _GBK_init(_RuneLocale *rl)
59 {
60 
61 	__mbrtowc = _GBK_mbrtowc;
62 	__wcrtomb = _GBK_wcrtomb;
63 	__mbsinit = _GBK_mbsinit;
64 	_CurrentRuneLocale = rl;
65 	__mb_cur_max = 2;
66 	__mb_sb_limit = 128;
67 	return (0);
68 }
69 
70 static int
71 _GBK_mbsinit(const mbstate_t *ps)
72 {
73 
74 	return (ps == NULL || ((const _GBKState *)ps)->ch == 0);
75 }
76 
77 static __inline int
78 _gbk_check(u_int c)
79 {
80 
81 	c &= 0xff;
82 	return ((c >= 0x81 && c <= 0xfe) ? 2 : 1);
83 }
84 
85 static size_t
86 _GBK_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
87     mbstate_t * __restrict ps)
88 {
89 	_GBKState *gs;
90 	wchar_t wc;
91 	size_t len;
92 
93 	gs = (_GBKState *)ps;
94 
95 	if ((gs->ch & ~0xFF) != 0) {
96 		/* Bad conversion state. */
97 		errno = EINVAL;
98 		return ((size_t)-1);
99 	}
100 
101 	if (s == NULL) {
102 		s = "";
103 		n = 1;
104 		pwc = NULL;
105 	}
106 
107 	if (n == 0)
108 		/* Incomplete multibyte sequence */
109 		return ((size_t)-2);
110 
111 	if (gs->ch != 0) {
112 		if (*s == '\0') {
113 			errno = EILSEQ;
114 			return ((size_t)-1);
115 		}
116 		wc = (gs->ch << 8) | (*s & 0xFF);
117 		if (pwc != NULL)
118 			*pwc = wc;
119 		gs->ch = 0;
120 		return (1);
121 	}
122 
123 	len = (size_t)_gbk_check(*s);
124 	wc = *s++ & 0xff;
125 	if (len == 2) {
126 		if (n < 2) {
127 			/* Incomplete multibyte sequence */
128 			gs->ch = wc;
129 			return ((size_t)-2);
130 		}
131 		if (*s == '\0') {
132 			errno = EILSEQ;
133 			return ((size_t)-1);
134 		}
135 		wc = (wc << 8) | (*s++ & 0xff);
136 		if (pwc != NULL)
137 			*pwc = wc;
138                 return (2);
139 	} else {
140 		if (pwc != NULL)
141 			*pwc = wc;
142 		return (wc == L'\0' ? 0 : 1);
143 	}
144 }
145 
146 static size_t
147 _GBK_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
148 {
149 	_GBKState *gs;
150 
151 	gs = (_GBKState *)ps;
152 
153 	if (gs->ch != 0) {
154 		errno = EINVAL;
155 		return ((size_t)-1);
156 	}
157 
158 	if (s == NULL)
159 		/* Reset to initial shift state (no-op) */
160 		return (1);
161 	if (wc & 0x8000) {
162 		*s++ = (wc >> 8) & 0xff;
163 		*s = wc & 0xff;
164 		return (2);
165 	}
166 	*s = wc & 0xff;
167 	return (1);
168 }
169