xref: /freebsd/lib/libc/locale/wcsnrtombs.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*-
2  * Copyright (c) 2002-2004 Tim J. Robbins.
3  * All rights reserved.
4  *
5  * Copyright (c) 2011 The FreeBSD Foundation
6  * All rights reserved.
7  * Portions of this software were developed by David Chisnall
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <limits.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <wchar.h>
39 #include "mblocal.h"
40 
41 size_t
42 wcsnrtombs_l(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
43     size_t len, mbstate_t * __restrict ps, locale_t locale)
44 {
45 	FIX_LOCALE(locale);
46 	if (ps == NULL)
47 		ps = &locale->wcsnrtombs;
48 	return (XLOCALE_CTYPE(locale)->__wcsnrtombs(dst, src, nwc, len, ps));
49 }
50 size_t
51 wcsnrtombs(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
52     size_t len, mbstate_t * __restrict ps)
53 {
54 	return wcsnrtombs_l(dst, src, nwc, len, ps, __get_locale());
55 }
56 
57 
58 size_t
59 __wcsnrtombs_std(char * __restrict dst, const wchar_t ** __restrict src,
60     size_t nwc, size_t len, mbstate_t * __restrict ps)
61 {
62 	mbstate_t mbsbak;
63 	char buf[MB_LEN_MAX];
64 	const wchar_t *s;
65 	size_t nbytes;
66 	size_t nb;
67 	struct xlocale_ctype *l = XLOCALE_CTYPE(__get_locale());
68 
69 	s = *src;
70 	nbytes = 0;
71 
72 	if (dst == NULL) {
73 		while (nwc-- > 0) {
74 			if ((nb = l->__wcrtomb(buf, *s, ps)) == (size_t)-1)
75 				/* Invalid character - wcrtomb() sets errno. */
76 				return ((size_t)-1);
77 			else if (*s == L'\0')
78 				return (nbytes + nb - 1);
79 			s++;
80 			nbytes += nb;
81 		}
82 		return (nbytes);
83 	}
84 
85 	while (len > 0 && nwc-- > 0) {
86 		if (len > (size_t)MB_CUR_MAX) {
87 			/* Enough space to translate in-place. */
88 			if ((nb = l->__wcrtomb(dst, *s, ps)) == (size_t)-1) {
89 				*src = s;
90 				return ((size_t)-1);
91 			}
92 		} else {
93 			/*
94 			 * May not be enough space; use temp. buffer.
95 			 *
96 			 * We need to save a copy of the conversion state
97 			 * here so we can restore it if the multibyte
98 			 * character is too long for the buffer.
99 			 */
100 			mbsbak = *ps;
101 			if ((nb = l->__wcrtomb(buf, *s, ps)) == (size_t)-1) {
102 				*src = s;
103 				return ((size_t)-1);
104 			}
105 			if (nb > (int)len) {
106 				/* MB sequence for character won't fit. */
107 				*ps = mbsbak;
108 				break;
109 			}
110 			memcpy(dst, buf, nb);
111 		}
112 		if (*s == L'\0') {
113 			*src = NULL;
114 			return (nbytes + nb - 1);
115 		}
116 		s++;
117 		dst += nb;
118 		len -= nb;
119 		nbytes += nb;
120 	}
121 	*src = s;
122 	return (nbytes);
123 }
124