strsep.c revision 331722
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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#if defined(LIBC_SCCS) && !defined(lint) 31static char sccsid[] = "@(#)strsep.c 8.1 (Berkeley) 6/4/93"; 32#endif /* LIBC_SCCS and not lint */ 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: stable/11/sys/libkern/strsep.c 331722 2018-03-29 02:50:57Z eadler $"); 35 36#include <sys/param.h> 37#include <sys/libkern.h> 38 39/* 40 * Get next token from string *stringp, where tokens are possibly-empty 41 * strings separated by characters from delim. 42 * 43 * Writes NULs into the string at *stringp to end tokens. 44 * delim need not remain constant from call to call. 45 * On return, *stringp points past the last NUL written (if there might 46 * be further tokens), or is NULL (if there are definitely no more tokens). 47 * 48 * If *stringp is NULL, strsep returns NULL. 49 */ 50char * 51strsep(stringp, delim) 52 char **stringp; 53 const char *delim; 54{ 55 char *s; 56 const char *spanp; 57 int c, sc; 58 char *tok; 59 60 if ((s = *stringp) == NULL) 61 return (NULL); 62 for (tok = s;;) { 63 c = *s++; 64 spanp = delim; 65 do { 66 if ((sc = *spanp++) == c) { 67 if (c == 0) 68 s = NULL; 69 else 70 s[-1] = 0; 71 *stringp = s; 72 return (tok); 73 } 74 } while (sc != 0); 75 } 76 /* NOTREACHED */ 77} 78