xref: /freebsd/lib/libc/locale/gbk.c (revision 7bd6fde3)
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 static size_t	_GBK_mbrtowc(wchar_t * __restrict, const char * __restrict,
46 		    size_t, mbstate_t * __restrict);
47 static int	_GBK_mbsinit(const mbstate_t *);
48 static size_t	_GBK_wcrtomb(char * __restrict, wchar_t,
49 		    mbstate_t * __restrict);
50 
51 typedef struct {
52 	wchar_t	ch;
53 } _GBKState;
54 
55 int
56 _GBK_init(_RuneLocale *rl)
57 {
58 
59 	__mbrtowc = _GBK_mbrtowc;
60 	__wcrtomb = _GBK_wcrtomb;
61 	__mbsinit = _GBK_mbsinit;
62 	_CurrentRuneLocale = rl;
63 	__mb_cur_max = 2;
64 	return (0);
65 }
66 
67 static int
68 _GBK_mbsinit(const mbstate_t *ps)
69 {
70 
71 	return (ps == NULL || ((const _GBKState *)ps)->ch == 0);
72 }
73 
74 static __inline int
75 _gbk_check(u_int c)
76 {
77 
78 	c &= 0xff;
79 	return ((c >= 0x81 && c <= 0xfe) ? 2 : 1);
80 }
81 
82 static size_t
83 _GBK_mbrtowc(wchar_t * __restrict pwc, const char * __restrict s, size_t n,
84     mbstate_t * __restrict ps)
85 {
86 	_GBKState *gs;
87 	wchar_t wc;
88 	size_t len;
89 
90 	gs = (_GBKState *)ps;
91 
92 	if ((gs->ch & ~0xFF) != 0) {
93 		/* Bad conversion state. */
94 		errno = EINVAL;
95 		return ((size_t)-1);
96 	}
97 
98 	if (s == NULL) {
99 		s = "";
100 		n = 1;
101 		pwc = NULL;
102 	}
103 
104 	if (n == 0)
105 		/* Incomplete multibyte sequence */
106 		return ((size_t)-2);
107 
108 	if (gs->ch != 0) {
109 		if (*s == '\0') {
110 			errno = EILSEQ;
111 			return ((size_t)-1);
112 		}
113 		wc = (gs->ch << 8) | (*s & 0xFF);
114 		if (pwc != NULL)
115 			*pwc = wc;
116 		gs->ch = 0;
117 		return (1);
118 	}
119 
120 	len = (size_t)_gbk_check(*s);
121 	wc = *s++ & 0xff;
122 	if (len == 2) {
123 		if (n < 2) {
124 			/* Incomplete multibyte sequence */
125 			gs->ch = wc;
126 			return ((size_t)-2);
127 		}
128 		if (*s == '\0') {
129 			errno = EILSEQ;
130 			return ((size_t)-1);
131 		}
132 		wc = (wc << 8) | (*s++ & 0xff);
133 		if (pwc != NULL)
134 			*pwc = wc;
135                 return (2);
136 	} else {
137 		if (pwc != NULL)
138 			*pwc = wc;
139 		return (wc == L'\0' ? 0 : 1);
140 	}
141 }
142 
143 static size_t
144 _GBK_wcrtomb(char * __restrict s, wchar_t wc, mbstate_t * __restrict ps)
145 {
146 	_GBKState *gs;
147 
148 	gs = (_GBKState *)ps;
149 
150 	if (gs->ch != 0) {
151 		errno = EINVAL;
152 		return ((size_t)-1);
153 	}
154 
155 	if (s == NULL)
156 		/* Reset to initial shift state (no-op) */
157 		return (1);
158 	if (wc & 0x8000) {
159 		*s++ = (wc >> 8) & 0xff;
160 		*s = wc & 0xff;
161 		return (2);
162 	}
163 	*s = wc & 0xff;
164 	return (1);
165 }
166