xref: /illumos-gate/usr/src/lib/libc/port/locale/wcsnrtombs.c (revision b6805bf78d2bbbeeaea8909a05623587b42d58b3)
1 /*
2  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
3  * Copyright (c) 2002-2004 Tim J. Robbins.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include "lint.h"
29 #include <limits.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <wchar.h>
33 #include "mblocal.h"
34 
35 size_t
36 wcsnrtombs(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src,
37     size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps)
38 {
39 	static mbstate_t mbs;
40 
41 	if (ps == NULL)
42 		ps = &mbs;
43 	return (__wcsnrtombs(dst, src, nwc, len, ps));
44 }
45 
46 size_t
47 __wcsnrtombs_std(char *_RESTRICT_KYWD dst, const wchar_t **_RESTRICT_KYWD src,
48     size_t nwc, size_t len, mbstate_t *_RESTRICT_KYWD ps)
49 {
50 	mbstate_t mbsbak;
51 	char buf[MB_LEN_MAX];
52 	const wchar_t *s;
53 	size_t nbytes;
54 	size_t nb;
55 
56 	s = *src;
57 	nbytes = 0;
58 
59 	if (dst == NULL) {
60 		while (nwc-- > 0) {
61 			if ((nb = __wcrtomb(buf, *s, ps)) == (size_t)-1)
62 				/* Invalid character - wcrtomb() sets errno. */
63 				return ((size_t)-1);
64 			else if (*s == L'\0')
65 				return (nbytes + nb - 1);
66 			s++;
67 			nbytes += nb;
68 		}
69 		return (nbytes);
70 	}
71 
72 	while (len > 0 && nwc-- > 0) {
73 		if (len > (size_t)MB_CUR_MAX) {
74 			/* Enough space to translate in-place. */
75 			if ((nb = __wcrtomb(dst, *s, ps)) == (size_t)-1) {
76 				*src = s;
77 				return ((size_t)-1);
78 			}
79 		} else {
80 			/*
81 			 * May not be enough space; use temp. buffer.
82 			 *
83 			 * We need to save a copy of the conversion state
84 			 * here so we can restore it if the multibyte
85 			 * character is too long for the buffer.
86 			 */
87 			mbsbak = *ps;
88 			if ((nb = __wcrtomb(buf, *s, ps)) == (size_t)-1) {
89 				*src = s;
90 				return ((size_t)-1);
91 			}
92 			if (nb > (int)len) {
93 				/* MB sequence for character won't fit. */
94 				*ps = mbsbak;
95 				break;
96 			}
97 			(void) memcpy(dst, buf, nb);
98 		}
99 		if (*s == L'\0') {
100 			*src = NULL;
101 			return (nbytes + nb - 1);
102 		}
103 		s++;
104 		dst += nb;
105 		len -= nb;
106 		nbytes += nb;
107 	}
108 	*src = s;
109 	return (nbytes);
110 }
111