source: vendor/FreeBSD-libc/5.3/string/wcstok.c

/*-
 * Copyright (c) 1998 Softweyr LLC.  All rights reserved.
 *
 * strtok_r, from Berkeley strtok
 * Oct 13, 1998 by Wes Peters <wes@softweyr.com>
 *
 * Copyright (c) 1988, 1993
 *      The Regents of the University of California.  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
 *    notices, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notices, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Softweyr LLC, the
 *      University of California, Berkeley, and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS 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 SOFTWEYR LLC, THE
 * REGENTS, 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: src/lib/libc/string/wcstok.c,v 1.2 2003/03/12 06:41:49 tjr Exp $");

#include <wchar.h>

wchar_t *
wcstok(wchar_t * __restrict s, const wchar_t * __restrict delim,
    wchar_t ** __restrict last)
{
        const wchar_t *spanp;
        wchar_t *tok;
        wchar_t c, sc;

        if (s == NULL && (s = *last) == NULL)
                return (NULL);

        /*
         * Skip (span) leading delimiters (s += wcsspn(s, delim), sort of).
         */
cont:
        c = *s++;
        for (spanp = delim; (sc = *spanp++) != L'\0';) {
                if (c == sc)
                        goto cont;
        }

        if (c == L'\0') {       /* no non-delimiter characters */
                *last = NULL;
                return (NULL);
        }
        tok = s - 1;

        /*
         * Scan token (scan for delimiters: s += wcscspn(s, delim), sort of).
         * Note that delim must have one NUL; we stop if we see that, too.
         */
        for (;;) {
                c = *s++;
                spanp = delim;
                do {
                        if ((sc = *spanp++) == c) {
                                if (c == L'\0')
                                        s = NULL;
                                else
                                        s[-1] = L'\0';
                                *last = s;
                                return (tok);
                        }
                } while (sc != L'\0');
        }
        /* NOTREACHED */
}