xref: /onnv-gate/usr/src/lib/libbc/libc/gen/common/strtok.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*      Copyright (c) 1984 AT&T */
23*0Sstevel@tonic-gate /*        All Rights Reserved   */
24*0Sstevel@tonic-gate 
25*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"  /* from S5R2 1.2 */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate /*LINTLIBRARY*/
28*0Sstevel@tonic-gate /*
29*0Sstevel@tonic-gate  * uses strpbrk and strspn to break string into tokens on
30*0Sstevel@tonic-gate  * sequentially subsequent calls.  returns NULL when no
31*0Sstevel@tonic-gate  * non-separator characters remain.
32*0Sstevel@tonic-gate  * `subsequent' calls are calls with first argument NULL.
33*0Sstevel@tonic-gate  */
34*0Sstevel@tonic-gate 
35*0Sstevel@tonic-gate #define	NULL	(char*)0
36*0Sstevel@tonic-gate 
37*0Sstevel@tonic-gate extern int strspn();
38*0Sstevel@tonic-gate extern char *strpbrk();
39*0Sstevel@tonic-gate 
40*0Sstevel@tonic-gate char *
strtok(string,sepset)41*0Sstevel@tonic-gate strtok(string, sepset)
42*0Sstevel@tonic-gate char	*string, *sepset;
43*0Sstevel@tonic-gate {
44*0Sstevel@tonic-gate 	register char	*p, *q, *r;
45*0Sstevel@tonic-gate 	static char	*savept;
46*0Sstevel@tonic-gate 
47*0Sstevel@tonic-gate 	/*first or subsequent call*/
48*0Sstevel@tonic-gate 	p = (string == NULL)? savept: string;
49*0Sstevel@tonic-gate 
50*0Sstevel@tonic-gate 	if(p == 0)		/* return if no tokens remaining */
51*0Sstevel@tonic-gate 		return(NULL);
52*0Sstevel@tonic-gate 
53*0Sstevel@tonic-gate 	q = p + strspn(p, sepset);	/* skip leading separators */
54*0Sstevel@tonic-gate 
55*0Sstevel@tonic-gate 	if(*q == '\0')		/* return if no tokens remaining */
56*0Sstevel@tonic-gate 		return(NULL);
57*0Sstevel@tonic-gate 
58*0Sstevel@tonic-gate 	if((r = strpbrk(q, sepset)) == NULL)	/* move past token */
59*0Sstevel@tonic-gate 		savept = 0;	/* indicate this is last token */
60*0Sstevel@tonic-gate 	else {
61*0Sstevel@tonic-gate 		*r = '\0';
62*0Sstevel@tonic-gate 		savept = ++r;
63*0Sstevel@tonic-gate 	}
64*0Sstevel@tonic-gate 	return(q);
65*0Sstevel@tonic-gate }
66