1 /* $NetBSD: wcsftime.c,v 1.5 2013/08/19 20:41:15 joerg 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 28 #include <sys/cdefs.h> 29 __RCSID("$NetBSD: wcsftime.c,v 1.5 2013/08/19 20:41:15 joerg Exp $"); 30 31 #define __SETLOCALE_SOURCE__ 32 #include "namespace.h" 33 #include <errno.h> 34 #include <limits.h> 35 #include <locale.h> 36 #include <stdlib.h> 37 #include <time.h> 38 #include <wchar.h> 39 40 #include "setlocale_local.h" 41 42 __weak_alias(wcsftime_l, _wcsftime_l) 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 58 wcsftime(wchar_t *wcs, size_t maxsize, 59 const wchar_t *format, const struct tm *timeptr) 60 { 61 return wcsftime_l(wcs, maxsize, format, timeptr, _current_locale()); 62 } 63 64 size_t 65 wcsftime_l(wchar_t *wcs, size_t maxsize, 66 const wchar_t *format, const struct tm *timeptr, locale_t loc) 67 { 68 char *dst, *dstp, *sformat; 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 sflen = wcstombs_l(NULL, format, 0, loc); 79 if (sflen == (size_t)-1) 80 goto error; 81 if ((sformat = malloc(sflen + 1)) == NULL) 82 goto error; 83 wcstombs_l(sformat, format, sflen + 1, loc); 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_L(loc) <= maxsize) { 92 /* maxsize is preposterously large - avoid int. overflow. */ 93 errno = EINVAL; 94 goto error; 95 } 96 dst = malloc(maxsize * MB_CUR_MAX_L(loc)); 97 if (dst == NULL) 98 goto error; 99 if (strftime_l(dst, maxsize, sformat, timeptr, loc) == 0) 100 goto error; 101 dstp = dst; 102 n = mbstowcs_l(wcs, dstp, maxsize, loc); 103 if (n == (size_t)-2 || n == (size_t)-1) 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