1 /* 2 * Copyright (c) 1988 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static char sccsid[] = "@(#)strtok.c 5.5 (Berkeley) 08/01/88"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 #include <stdio.h> 23 24 char * 25 strtok(s, delim) 26 register char *s, *delim; 27 { 28 register char *spanp; 29 register int c, sc; 30 char *tok; 31 static char *last; 32 33 34 if (s == NULL && (s = last) == NULL) 35 return (NULL); 36 37 /* 38 * Skip (span) leading delimiters (s += strspn(s, delim), sort of). 39 */ 40 cont: 41 c = *s++; 42 for (spanp = delim; (sc = *spanp++) != 0;) { 43 if (c == sc) 44 goto cont; 45 } 46 47 if (c == 0) { /* no non-delimiter characters */ 48 last = NULL; 49 return (NULL); 50 } 51 tok = s - 1; 52 53 /* 54 * Scan token (scan for delimiters: s += strcspn(s, delim), sort of). 55 * Note that delim must have one NUL; we stop if we see that, too. 56 */ 57 for (;;) { 58 c = *s++; 59 spanp = delim; 60 do { 61 if ((sc = *spanp++) == c) { 62 if (c == 0) 63 s = NULL; 64 else 65 s[-1] = 0; 66 last = s; 67 return (tok); 68 } 69 } while (sc != 0); 70 } 71 /* NOTREACHED */ 72 } 73