string/FreeBSD/wcstok.c

   1 /*-
   2  * Copyright (c) 1998 Softweyr LLC.  All rights reserved.
   3  *
   4  * strtok_r, from Berkeley strtok
   5  * Oct 13, 1998 by Wes Peters <wes@softweyr.com>
   6  *
   7  * Copyright (c) 1988, 1993
   8  *      The Regents of the University of California.  All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notices, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notices, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by Softweyr LLC, the
  21  *      University of California, Berkeley, and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY SOFTWEYR LLC, THE REGENTS AND CONTRIBUTORS
  27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  28  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  29  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL SOFTWEYR LLC, THE
  30  * REGENTS, OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  31  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  32  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  33  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  34  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  35  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  36  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  37  */
  38
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD: src/lib/libc/string/wcstok.c,v 1.2 2003/03/12 06:41:49 tjr Exp $");
  41
  42 #include <wchar.h>
  43
  44 wchar_t *
  45 wcstok(wchar_t * __restrict s, const wchar_t * __restrict delim,
  46     wchar_t ** __restrict last)
  47 {
  48         const wchar_t *spanp;
  49         wchar_t *tok;
  50         wchar_t c, sc;
  51
  52         if (s == NULL && (s = *last) == NULL)
  53                 return (NULL);
  54
  55         /*
  56          * Skip (span) leading delimiters (s += wcsspn(s, delim), sort of).
  57          */
  58 cont:
  59         c = *s++;
  60         for (spanp = delim; (sc = *spanp++) != L'\0';) {
  61                 if (c == sc)
  62                         goto cont;
  63         }
  64
  65         if (c == L'\0') {       /* no non-delimiter characters */
  66                 *last = NULL;
  67                 return (NULL);
  68         }
  69         tok = s - 1;
  70
  71         /*
  72          * Scan token (scan for delimiters: s += wcscspn(s, delim), sort of).
  73          * Note that delim must have one NUL; we stop if we see that, too.
  74          */
  75         for (;;) {
  76                 c = *s++;
  77                 spanp = delim;
  78                 do {
  79                         if ((sc = *spanp++) == c) {
  80                                 if (c == L'\0')
  81                                         s = NULL;
  82                                 else
  83                                         s[-1] = L'\0';
  84                                 *last = s;
  85                                 return (tok);
  86                         }
  87                 } while (sc != L'\0');
  88         }
  89         /* NOTREACHED */
  90 }