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 *
strtok(char * s,const char * delim)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 *
strtok_r(char * s,const char * delim,char ** last)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