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