1 /* $NetBSD: wcsftime.c,v 1.2 2006/10/04 14:19:16 tnozaki Exp $ */
2 /*-
3 * Copyright (c) 2002 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 #include <LibConfig.h>
28 #include <sys/EfiCdefs.h>
29 #if defined(LIBC_SCCS) && !defined(lint)
30 #if 0
31 __FBSDID("$FreeBSD: src/lib/libc/locale/wcsftime.c,v 1.4 2004/04/07 09:47:56 tjr Exp $");
32 #else
33 __RCSID("$NetBSD: wcsftime.c,v 1.2 2006/10/04 14:19:16 tnozaki Exp $");
34 #endif
35 #endif /* LIBC_SCCS and not lint */
36
37 #include <errno.h>
38 #include <limits.h>
39 #include <stdlib.h>
40 #include <time.h>
41 #include <wchar.h>
42 #include <machine/int_limits.h>
43
44 /*
45 * Convert date and time to a wide-character string.
46 *
47 * This is the wide-character counterpart of strftime(). So that we do not
48 * have to duplicate the code of strftime(), we convert the format string to
49 * multibyte, call strftime(), then convert the result back into wide
50 * characters.
51 *
52 * This technique loses in the presence of stateful multibyte encoding if any
53 * of the conversions in the format string change conversion state. When
54 * stateful encoding is implemented, we will need to reset the state between
55 * format specifications in the format string.
56 */
57 size_t
wcsftime(wchar_t * wcs,size_t maxsize,const wchar_t * format,const struct tm * timeptr)58 wcsftime(wchar_t *wcs, size_t maxsize,
59 const wchar_t *format, const struct tm *timeptr)
60 {
61 char *dst, *dstp, *sformat;
62 size_t n, sflen;
63 int sverrno;
64
65 sformat = dst = NULL;
66
67 /*
68 * Convert the supplied format string to a multibyte representation
69 * for strftime(), which only handles single-byte characters.
70 */
71 sflen = wcstombs(NULL, format, 0);
72 if (sflen == (size_t)-1)
73 goto error;
74 if ((sformat = malloc(sflen + 1)) == NULL)
75 goto error;
76 wcstombs(sformat, format, sflen + 1);
77
78 /*
79 * Allocate memory for longest multibyte sequence that will fit
80 * into the caller's buffer and call strftime() to fill it.
81 * Then, copy and convert the result back into wide characters in
82 * the caller's buffer.
83 */
84 if (SIZE_T_MAX / MB_CUR_MAX <= maxsize) {
85 /* maxsize is preposturously large - avoid int. overflow. */
86 errno = EINVAL;
87 goto error;
88 }
89 dst = malloc(maxsize * MB_CUR_MAX);
90 if (dst == NULL)
91 goto error;
92 if (strftime(dst, maxsize, sformat, timeptr) == 0)
93 goto error;
94 dstp = dst;
95 n = mbstowcs(wcs, dstp, maxsize);
96 if (n == (size_t)-2 || n == (size_t)-1)
97 goto error;
98
99 free(sformat);
100 free(dst);
101 return n;
102
103 error:
104 sverrno = errno;
105 free(sformat);
106 free(dst);
107 errno = sverrno;
108 return 0;
109 }
110