xref: /illumos-gate/usr/src/lib/libc/port/gen/strtok_r.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*	Copyright (c) 1988 AT&T	*/
30 /*	  All Rights Reserved  	*/
31 
32 
33 #pragma weak strtok_r = _strtok_r
34 
35 #include "synonyms.h"
36 #include <string.h>
37 #include <stddef.h>
38 #include <sys/types.h>
39 
40 /*
41  * uses strpbrk and strspn to break string into tokens on
42  * sequentially subsequent calls.  returns NULL when no
43  * non-separator characters remain.
44  * `subsequent' calls are calls with first argument NULL.
45  */
46 char *
47 strtok_r(char *string, const char *sepset, char **lasts)
48 {
49 	char	*q, *r;
50 
51 	/* first or subsequent call */
52 	if (string == NULL)
53 		string = *lasts;
54 
55 	if (string == NULL)		/* return if no tokens remaining */
56 		return (NULL);
57 
58 	q = string + strspn(string, sepset);	/* skip leading separators */
59 
60 	if (*q == '\0')		/* return if no tokens remaining */
61 		return (NULL);
62 
63 	if ((r = strpbrk(q, sepset)) == NULL)	/* move past token */
64 		*lasts = NULL;	/* indicate this is last token */
65 	else {
66 		*r = '\0';
67 		*lasts = r + 1;
68 	}
69 	return (q);
70 }
71