1 /* $NetBSD: strtok.c,v 1.10 1999/09/20 04:39:49 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)strtok.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: strtok.c,v 1.10 1999/09/20 04:39:49 lukem Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include <assert.h> 46 #include <string.h> 47 48 char * 49 strtok(s, delim) 50 char *s; 51 const char *delim; 52 { 53 const char *spanp; 54 int c, sc; 55 char *tok; 56 static char *last; 57 58 /* s may be NULL */ 59 _DIAGASSERT(delim != NULL); 60 61 if (s == NULL && (s = last) == NULL) 62 return (NULL); 63 64 /* 65 * Skip (span) leading delimiters (s += strspn(s, delim), sort of). 66 */ 67 cont: 68 c = *s++; 69 for (spanp = delim; (sc = *spanp++) != 0;) { 70 if (c == sc) 71 goto cont; 72 } 73 74 if (c == 0) { /* no non-delimiter characters */ 75 last = NULL; 76 return (NULL); 77 } 78 tok = s - 1; 79 80 /* 81 * Scan token (scan for delimiters: s += strcspn(s, delim), sort of). 82 * Note that delim must have one NUL; we stop if we see that, too. 83 */ 84 for (;;) { 85 c = *s++; 86 spanp = delim; 87 do { 88 if ((sc = *spanp++) == c) { 89 if (c == 0) 90 s = NULL; 91 else 92 s[-1] = 0; 93 last = s; 94 return (tok); 95 } 96 } while (sc != 0); 97 } 98 /* NOTREACHED */ 99 } 100