1 /*
2 * Copyright 2010 Nexenta Systems, Inc. All rights reserved.
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
28 #include "lint.h"
29 #include "mse_int.h"
30 #include <errno.h>
31 #include <limits.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <time.h>
35 #include <wchar.h>
36 #include <alloca.h>
37
38 /*
39 * Convert date and time to a wide-character string.
40 *
41 * This is the wide-character counterpart of strftime(). So that we do not
42 * have to duplicate the code of strftime(), we convert the format string to
43 * multibyte, call strftime(), then convert the result back into wide
44 * characters.
45 *
46 * This technique loses in the presence of stateful multibyte encoding if any
47 * of the conversions in the format string change conversion state. When
48 * stateful encoding is implemented, we will need to reset the state between
49 * format specifications in the format string.
50 *
51 * Note carefully that prior to xpg5, the format was char *, not wchar_t.
52 */
53
54 /*
55 * Hmmm this is probably a bit backwards. As we are converting to single
56 * byte formats, perhaps we should not be doing a redundant conversion.
57 * Something to look at for the future.
58 */
59
60 size_t
__wcsftime_xpg5(wchar_t * wcs,size_t maxsize,const wchar_t * format,const struct tm * timeptr)61 __wcsftime_xpg5(wchar_t *wcs, size_t maxsize, const wchar_t *format,
62 const struct tm *timeptr)
63 {
64 static const mbstate_t initial = { 0 };
65 mbstate_t mbs;
66 char *dst, *sformat;
67 const char *dstp;
68 const wchar_t *formatp;
69 size_t n, sflen;
70 int sverrno;
71
72 sformat = dst = NULL;
73
74 /*
75 * Convert the supplied format string to a multibyte representation
76 * for strftime(), which only handles single-byte characters.
77 */
78 mbs = initial;
79 formatp = format;
80 sflen = wcsrtombs(NULL, &formatp, 0, &mbs);
81 if (sflen == (size_t)-1)
82 goto error;
83 if ((sformat = malloc(sflen + 1)) == NULL)
84 goto error;
85 mbs = initial;
86 (void) wcsrtombs(sformat, &formatp, sflen + 1, &mbs);
87
88 /*
89 * Allocate memory for longest multibyte sequence that will fit
90 * into the caller's buffer and call strftime() to fill it.
91 * Then, copy and convert the result back into wide characters in
92 * the caller's buffer.
93 */
94 if (LONG_MAX / MB_CUR_MAX <= maxsize) {
95 /* maxsize is prepostorously large - avoid int. overflow. */
96 errno = EINVAL;
97 goto error;
98 }
99 if ((dst = malloc(maxsize * MB_CUR_MAX)) == NULL)
100 goto error;
101 if (strftime(dst, maxsize, sformat, timeptr) == 0)
102 goto error;
103 dstp = dst;
104 mbs = initial;
105 n = mbsrtowcs(wcs, &dstp, maxsize, &mbs);
106 if (n == (size_t)-2 || n == (size_t)-1 || dstp != NULL)
107 goto error;
108
109 free(sformat);
110 free(dst);
111 return (n);
112
113 error:
114 sverrno = errno;
115 free(sformat);
116 free(dst);
117 errno = sverrno;
118 return (0);
119 }
120
121 size_t
wcsftime(wchar_t * wcs,size_t maxsize,const char * format,const struct tm * timeptr)122 wcsftime(wchar_t *wcs, size_t maxsize, const char *format,
123 const struct tm *timeptr)
124 {
125 int len;
126 wchar_t *wfmt;
127 size_t rv;
128
129 /* Convert the format (mb string) to wide char array */
130 len = strlen(format) + 1;
131 wfmt = malloc(sizeof (wchar_t) * len);
132 if (mbstowcs(wfmt, format, len) == (size_t)-1) {
133 free(wfmt);
134 return (0);
135 }
136 rv = __wcsftime_xpg5(wcs, maxsize, wfmt, timeptr);
137 free(wfmt);
138 return (rv);
139 }
140