1/*- 2 * Copyright (c) 2002 Tim J. Robbins 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28 29#include <errno.h> 30#include <stdint.h> 31#include <stdlib.h> 32#include <time.h> 33 34#include <errno_private.h> 35#include <wchar_private.h> 36 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 */ 51size_t 52wcsftime(wchar_t *wcs, size_t maxsize, const wchar_t *format, 53 const struct tm *timeptr) 54{ 55 static const mbstate_t initial; 56 mbstate_t mbs; 57 char *dst, *sformat; 58 const char *dstp; 59 const wchar_t *formatp; 60 size_t n, sflen; 61 int sverrno; 62 63 sformat = dst = NULL; 64 65 /* 66 * Convert the supplied format string to a multibyte representation 67 * for strftime(), which only handles single-byte characters. 68 */ 69 mbs = initial; 70 formatp = format; 71 sflen = __wcsrtombs(NULL, &formatp, 0, &mbs); 72 if (sflen == (size_t)-1) 73 goto error; 74 if ((sformat = malloc(sflen + 1)) == NULL) 75 goto error; 76 mbs = initial; 77 __wcsrtombs(sformat, &formatp, sflen + 1, &mbs); 78 79 /* 80 * Allocate memory for longest multibyte sequence that will fit 81 * into the caller's buffer and call strftime() to fill it. 82 * Then, copy and convert the result back into wide characters in 83 * the caller's buffer. 84 */ 85 if (SIZE_MAX / MB_CUR_MAX <= maxsize) { 86 /* maxsize is prepostorously large - avoid int. overflow. */ 87 __set_errno(EINVAL); 88 goto error; 89 } 90 if ((dst = malloc(maxsize * MB_CUR_MAX)) == NULL) 91 goto error; 92 if (strftime(dst, maxsize, sformat, timeptr) == 0) 93 goto error; 94 dstp = dst; 95 mbs = initial; 96 n = __mbsrtowcs(wcs, &dstp, maxsize, &mbs); 97 if (n == (size_t)-2 || n == (size_t)-1 || dstp != NULL) 98 goto error; 99 100 free(sformat); 101 free(dst); 102 103 return n; 104 105error: 106 sverrno = errno; 107 free(sformat); 108 free(dst); 109 __set_errno(sverrno); 110 111 return 0; 112} 113