xref: /illumos-gate/usr/src/lib/libresolv2/common/bsd/strsep.c (revision f20211217f12ce291fd518e61065cd273f23e4ea)
1 /*
2  * Copyright (c) 1990, 1993
3  *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "port_before.h"
35 #include <sys/cdefs.h>
36 #include <string.h>
37 #include <stdio.h>
38 #include "port_after.h"
39 
40 #ifndef NEED_STRSEP
41 int __strsep_unneeded__;
42 #else
43 
44 /*%
45  * Get next token from string *stringp, where tokens are possibly-empty
46  * strings separated by characters from delim.
47  *
48  * Writes NULs into the string at *stringp to end tokens.
49  * delim need not remain constant from call to call.
50  * On return, *stringp points past the last NUL written (if there might
51  * be further tokens), or is NULL (if there are definitely no more tokens).
52  *
53  * If *stringp is NULL, strsep returns NULL.
54  */
55 char *
56 strsep(char **stringp, const char *delim) {
57 	char *s;
58 	const char *spanp;
59 	int c, sc;
60 	char *tok;
61 
62 	if ((s = *stringp) == NULL)
63 		return (NULL);
64 	for (tok = s;;) {
65 		c = *s++;
66 		spanp = delim;
67 		do {
68 			if ((sc = *spanp++) == c) {
69 				if (c == 0)
70 					s = NULL;
71 				else
72 					s[-1] = 0;
73 				*stringp = s;
74 				return (tok);
75 			}
76 		} while (sc != 0);
77 	}
78 	/* NOTREACHED */
79 }
80 
81 #endif /*NEED_STRSEP*/
82 
83 /*! \file */
84