freebsd-dev/lib/libc/locale/wctomb.c

/*-
 * Copyright (c) 2002, 2003 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 <string.h>
#include <wchar.h>

int
wctomb(char *s, wchar_t wchar)
{
	char buf[MB_LEN_MAX];
	size_t rval;

	if (s == NULL)
		/* No support for state dependent encodings. */
		return (0);
	if (s == NULL)
		s = buf;
	/*
	 * We pass NULL as the state pointer to wcrtomb() because we don't
	 * support state-dependent encodings and don't want to waste time
	 * creating a zeroed mbstate_t that will not be used.
	 */
	if ((rval = wcrtomb(s, wchar, NULL)) == (size_t)-1)
		return (-1);
	if (rval > INT_MAX) {
		errno = ERANGE;
		return (-1);
	}
	return ((int)rval);
}