freebsd-dev/lib/libc/locale/wcsftime.c
David Chisnall 3c87aa1d3d Implement xlocale APIs from Darwin, mainly for use by libc++. This adds a
load of _l suffixed versions of various standard library functions that use
the global locale, making them take an explicit locale parameter.  Also
adds support for per-thread locales.  This work was funded by the FreeBSD
Foundation.

Please test any code you have that uses the C standard locale functions!

Reviewed by:    das (gdtoa changes)
Approved by:    dim (mentor)
2011-11-20 14:45:42 +00:00

123 lines
3.9 KiB
C

/*-
* Copyright (c) 2002 Tim J. Robbins
* All rights reserved.
*
* Copyright (c) 2011 The FreeBSD Foundation
* All rights reserved.
* Portions of this software were developed by David Chisnall
* under sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <time.h>
#include <wchar.h>
#include "xlocale_private.h"
/*
* Convert date and time to a wide-character string.
*
* This is the wide-character counterpart of strftime(). So that we do not
* have to duplicate the code of strftime(), we convert the format string to
* multibyte, call strftime(), then convert the result back into wide
* characters.
*
* This technique loses in the presence of stateful multibyte encoding if any
* of the conversions in the format string change conversion state. When
* stateful encoding is implemented, we will need to reset the state between
* format specifications in the format string.
*/
size_t
wcsftime_l(wchar_t * __restrict wcs, size_t maxsize,
const wchar_t * __restrict format, const struct tm * __restrict timeptr,
locale_t locale)
{
static const mbstate_t initial;
mbstate_t mbs;
char *dst, *sformat;
const char *dstp;
const wchar_t *formatp;
size_t n, sflen;
int sverrno;
FIX_LOCALE(locale);
sformat = dst = NULL;
/*
* Convert the supplied format string to a multibyte representation
* for strftime(), which only handles single-byte characters.
*/
mbs = initial;
formatp = format;
sflen = wcsrtombs_l(NULL, &formatp, 0, &mbs, locale);
if (sflen == (size_t)-1)
goto error;
if ((sformat = malloc(sflen + 1)) == NULL)
goto error;
mbs = initial;
wcsrtombs_l(sformat, &formatp, sflen + 1, &mbs, locale);
/*
* Allocate memory for longest multibyte sequence that will fit
* into the caller's buffer and call strftime() to fill it.
* Then, copy and convert the result back into wide characters in
* the caller's buffer.
*/
if (SIZE_T_MAX / MB_CUR_MAX <= maxsize) {
/* maxsize is prepostorously large - avoid int. overflow. */
errno = EINVAL;
goto error;
}
if ((dst = malloc(maxsize * MB_CUR_MAX)) == NULL)
goto error;
if (strftime_l(dst, maxsize, sformat, timeptr, locale) == 0)
goto error;
dstp = dst;
mbs = initial;
n = mbsrtowcs_l(wcs, &dstp, maxsize, &mbs, locale);
if (n == (size_t)-2 || n == (size_t)-1 || dstp != NULL)
goto error;
free(sformat);
free(dst);
return (n);
error:
sverrno = errno;
free(sformat);
free(dst);
errno = sverrno;
return (0);
}
size_t
wcsftime(wchar_t * __restrict wcs, size_t maxsize,
const wchar_t * __restrict format, const struct tm * __restrict timeptr)
{
return wcsftime_l(wcs, maxsize, format, timeptr, __get_locale());
}