xref: /freebsd/lib/libc/locale/wcsnrtombs.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright 2013 Garrett D'Amore <garrett@damore.org>
5  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
6  * Copyright (c) 2002-2004 Tim J. Robbins.
7  * All rights reserved.
8  *
9  * Copyright (c) 2011 The FreeBSD Foundation
10  *
11  * Portions of this software were developed by David Chisnall
12  * under sponsorship from the FreeBSD Foundation.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
38 
39 #include <limits.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <wchar.h>
43 #include "mblocal.h"
44 
45 size_t
46 wcsnrtombs_l(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
47     size_t len, mbstate_t * __restrict ps, locale_t locale)
48 {
49 	FIX_LOCALE(locale);
50 	if (ps == NULL)
51 		ps = &(XLOCALE_CTYPE(locale)->wcsnrtombs);
52 	return (XLOCALE_CTYPE(locale)->__wcsnrtombs(dst, src, nwc, len, ps));
53 }
54 size_t
55 wcsnrtombs(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
56     size_t len, mbstate_t * __restrict ps)
57 {
58 	return wcsnrtombs_l(dst, src, nwc, len, ps, __get_locale());
59 }
60 
61 
62 size_t
63 __wcsnrtombs_std(char * __restrict dst, const wchar_t ** __restrict src,
64     size_t nwc, size_t len, mbstate_t * __restrict ps,
65     wcrtomb_pfn_t pwcrtomb)
66 {
67 	mbstate_t mbsbak;
68 	char buf[MB_LEN_MAX];
69 	const wchar_t *s;
70 	size_t nbytes;
71 	size_t nb;
72 
73 	s = *src;
74 	nbytes = 0;
75 
76 	if (dst == NULL) {
77 		while (nwc-- > 0) {
78 			if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1)
79 				/* Invalid character - wcrtomb() sets errno. */
80 				return ((size_t)-1);
81 			else if (*s == L'\0')
82 				return (nbytes + nb - 1);
83 			s++;
84 			nbytes += nb;
85 		}
86 		return (nbytes);
87 	}
88 
89 	while (len > 0 && nwc-- > 0) {
90 		if (len > (size_t)MB_CUR_MAX) {
91 			/* Enough space to translate in-place. */
92 			if ((nb = pwcrtomb(dst, *s, ps)) == (size_t)-1) {
93 				*src = s;
94 				return ((size_t)-1);
95 			}
96 		} else {
97 			/*
98 			 * May not be enough space; use temp. buffer.
99 			 *
100 			 * We need to save a copy of the conversion state
101 			 * here so we can restore it if the multibyte
102 			 * character is too long for the buffer.
103 			 */
104 			mbsbak = *ps;
105 			if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1) {
106 				*src = s;
107 				return ((size_t)-1);
108 			}
109 			if (nb > (int)len) {
110 				/* MB sequence for character won't fit. */
111 				*ps = mbsbak;
112 				break;
113 			}
114 			memcpy(dst, buf, nb);
115 		}
116 		if (*s == L'\0') {
117 			*src = NULL;
118 			return (nbytes + nb - 1);
119 		}
120 		s++;
121 		dst += nb;
122 		len -= nb;
123 		nbytes += nb;
124 	}
125 	*src = s;
126 	return (nbytes);
127 }
128