1 /* $OpenBSD: strsep.c,v 1.7 2014/02/05 20:42:32 stsp Exp $ */
2
3 /*-
4 * Copyright (c) 1990, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <string.h>
33
34 /*
35 * Get next token from string *stringp, where tokens are possibly-empty
36 * strings separated by characters from delim.
37 *
38 * Writes NULs into the string at *stringp to end tokens.
39 * delim need not remain constant from call to call.
40 * On return, *stringp points past the last NUL written (if there might
41 * be further tokens), or is NULL (if there are definitely no more tokens).
42 *
43 * If *stringp is NULL, strsep returns NULL.
44 */
45 char *
strsep(char ** stringp,const char * delim)46 strsep(char **stringp, const char *delim)
47 {
48 char *s;
49 const char *spanp;
50 int c, sc;
51 char *tok;
52
53 if ((s = *stringp) == NULL)
54 return (NULL);
55 for (tok = s;;) {
56 c = *s++;
57 spanp = delim;
58 do {
59 if ((sc = *spanp++) == c) {
60 if (c == 0)
61 s = NULL;
62 else
63 s[-1] = 0;
64 *stringp = s;
65 return (tok);
66 }
67 } while (sc != 0);
68 }
69 /* NOTREACHED */
70 }
71