1 /*-
2 * Copyright (c) 2002 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 * $FreeBSD: head/lib/libc/locale/wcsftime.c 227753 2011-11-20 14:45:42Z theraven $
32 */
33
34
35 #include <errno.h>
36 #include <limits.h>
37 #include <stdlib.h>
38 #include <time.h>
39 #include <wchar.h>
40 #include "xlocale_private.h"
41
42 /*
43 * Convert date and time to a wide-character string.
44 *
45 * This is the wide-character counterpart of strftime(). So that we do not
46 * have to duplicate the code of strftime(), we convert the format string to
47 * multibyte, call strftime(), then convert the result back into wide
48 * characters.
49 *
50 * This technique loses in the presence of stateful multibyte encoding if any
51 * of the conversions in the format string change conversion state. When
52 * stateful encoding is implemented, we will need to reset the state between
53 * format specifications in the format string.
54 */
55 size_t
wcsftime_l(wchar_t * __restrict wcs,size_t maxsize,const wchar_t * __restrict format,const struct tm * __restrict timeptr,locale_t locale)56 wcsftime_l(wchar_t * __restrict wcs, size_t maxsize,
57 const wchar_t * __restrict format, const struct tm * __restrict timeptr,
58 locale_t locale)
59 {
60 static const mbstate_t initial;
61 mbstate_t mbs;
62 char *dst, *sformat;
63 const char *dstp;
64 const wchar_t *formatp;
65 size_t n, sflen;
66 int sverrno;
67 FIX_LOCALE(locale);
68
69 sformat = dst = NULL;
70
71 /*
72 * Convert the supplied format string to a multibyte representation
73 * for strftime(), which only handles single-byte characters.
74 */
75 mbs = initial;
76 formatp = format;
77 sflen = wcsrtombs_l(NULL, &formatp, 0, &mbs, locale);
78 if (sflen == (size_t)-1)
79 goto error;
80 if ((sformat = malloc(sflen + 1)) == NULL)
81 goto error;
82 mbs = initial;
83 wcsrtombs_l(sformat, &formatp, sflen + 1, &mbs, locale);
84
85 /*
86 * Allocate memory for longest multibyte sequence that will fit
87 * into the caller's buffer and call strftime() to fill it.
88 * Then, copy and convert the result back into wide characters in
89 * the caller's buffer.
90 */
91 if (SIZE_T_MAX / MB_CUR_MAX <= maxsize) {
92 /* maxsize is prepostorously large - avoid int. overflow. */
93 errno = EINVAL;
94 goto error;
95 }
96 if ((dst = malloc(maxsize * MB_CUR_MAX)) == NULL)
97 goto error;
98 if (strftime_l(dst, maxsize, sformat, timeptr, locale) == 0)
99 goto error;
100 dstp = dst;
101 mbs = initial;
102 n = mbsrtowcs_l(wcs, &dstp, maxsize, &mbs, locale);
103 if (n == (size_t)-2 || n == (size_t)-1 || dstp != NULL)
104 goto error;
105
106 free(sformat);
107 free(dst);
108 return (n);
109
110 error:
111 sverrno = errno;
112 free(sformat);
113 free(dst);
114 errno = sverrno;
115 return (0);
116 }
117 size_t
wcsftime(wchar_t * __restrict wcs,size_t maxsize,const wchar_t * __restrict format,const struct tm * __restrict timeptr)118 wcsftime(wchar_t * __restrict wcs, size_t maxsize,
119 const wchar_t * __restrict format, const struct tm * __restrict timeptr)
120 {
121 return wcsftime_l(wcs, maxsize, format, timeptr, __get_locale());
122 }
123