xref: /freebsd/lib/libc/locale/wcsnrtombs.c (revision 4b9d6057)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 <limits.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <wchar.h>
40 #include "mblocal.h"
41 
42 size_t
43 wcsnrtombs_l(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
44     size_t len, mbstate_t * __restrict ps, locale_t locale)
45 {
46 	FIX_LOCALE(locale);
47 	if (ps == NULL)
48 		ps = &(XLOCALE_CTYPE(locale)->wcsnrtombs);
49 	return (XLOCALE_CTYPE(locale)->__wcsnrtombs(dst, src, nwc, len, ps));
50 }
51 size_t
52 wcsnrtombs(char * __restrict dst, const wchar_t ** __restrict src, size_t nwc,
53     size_t len, mbstate_t * __restrict ps)
54 {
55 	return wcsnrtombs_l(dst, src, nwc, len, ps, __get_locale());
56 }
57 
58 
59 size_t
60 __wcsnrtombs_std(char * __restrict dst, const wchar_t ** __restrict src,
61     size_t nwc, size_t len, mbstate_t * __restrict ps,
62     wcrtomb_pfn_t pwcrtomb)
63 {
64 	mbstate_t mbsbak;
65 	char buf[MB_LEN_MAX];
66 	const wchar_t *s;
67 	size_t nbytes;
68 	size_t nb;
69 
70 	s = *src;
71 	nbytes = 0;
72 
73 	if (dst == NULL) {
74 		while (nwc-- > 0) {
75 			if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1)
76 				/* Invalid character - wcrtomb() sets errno. */
77 				return ((size_t)-1);
78 			else if (*s == L'\0')
79 				return (nbytes + nb - 1);
80 			s++;
81 			nbytes += nb;
82 		}
83 		return (nbytes);
84 	}
85 
86 	while (len > 0 && nwc-- > 0) {
87 		if (len > (size_t)MB_CUR_MAX) {
88 			/* Enough space to translate in-place. */
89 			if ((nb = pwcrtomb(dst, *s, ps)) == (size_t)-1) {
90 				*src = s;
91 				return ((size_t)-1);
92 			}
93 		} else {
94 			/*
95 			 * May not be enough space; use temp. buffer.
96 			 *
97 			 * We need to save a copy of the conversion state
98 			 * here so we can restore it if the multibyte
99 			 * character is too long for the buffer.
100 			 */
101 			mbsbak = *ps;
102 			if ((nb = pwcrtomb(buf, *s, ps)) == (size_t)-1) {
103 				*src = s;
104 				return ((size_t)-1);
105 			}
106 			if (nb > (int)len) {
107 				/* MB sequence for character won't fit. */
108 				*ps = mbsbak;
109 				break;
110 			}
111 			memcpy(dst, buf, nb);
112 		}
113 		if (*s == L'\0') {
114 			*src = NULL;
115 			return (nbytes + nb - 1);
116 		}
117 		s++;
118 		dst += nb;
119 		len -= nb;
120 		nbytes += nb;
121 	}
122 	*src = s;
123 	return (nbytes);
124 }
125