diff options
Diffstat (limited to 'lib/libc/locale/wcsftime.c')
-rw-r--r-- | lib/libc/locale/wcsftime.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/lib/libc/locale/wcsftime.c b/lib/libc/locale/wcsftime.c new file mode 100644 index 0000000..7a54fc0 --- /dev/null +++ b/lib/libc/locale/wcsftime.c @@ -0,0 +1,105 @@ +/*- + * Copyright (c) 2002 Tim J. Robbins + * All rights reserved. + * + * 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> + +/* + * 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(wchar_t * __restrict wcs, size_t maxsize, + const wchar_t * __restrict format, const struct tm * __restrict timeptr) +{ + static const mbstate_t initial; + mbstate_t mbs; + char *dst, *dstp, *sformat; + size_t n, sflen; + int sverrno; + + sformat = dst = NULL; + + /* + * Convert the supplied format string to a multibyte representation + * for strftime(), which only handles single-byte characters. + */ + mbs = initial; + sflen = wcsrtombs(NULL, &format, 0, &mbs); + if (sflen == (size_t)-1) + goto error; + if ((sformat = malloc(sflen + 1)) == NULL) + goto error; + mbs = initial; + wcsrtombs(sformat, &format, sflen + 1, &mbs); + + /* + * 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(dst, maxsize, sformat, timeptr) == 0) + goto error; + dstp = dst; + mbs = initial; + n = mbsrtowcs(wcs, (const char **)&dstp, maxsize, &mbs); + 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); +} |