usr/src/lib/libc/port/gen/strsep.c

   1 /*
   2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
   3  * Use is subject to license terms.
   4  */
   5
   6 /*      $OpenBSD: strsep.c,v 1.3 1997/08/20 04:28:14 millert Exp $      */
   7
   8 /*
   9  * Copyright (c) 1990, 1993
  10  *      The Regents of the University of California.  All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. All advertising materials mentioning features or use of this software
  21  *    must display the following acknowledgement:
  22  *      This product includes software developed by the University of
  23  *      California, Berkeley and its contributors.
  24  * 4. Neither the name of the University nor the names of its contributors
  25  *    may be used to endorse or promote products derived from this software
  26  *    without specific prior written permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  38  * SUCH DAMAGE.
  39  */
  40
  41 #include "lint.h"
  42 #include <string.h>
  43 #include <stdio.h>
  44
  45 #if defined(LIBC_SCCS) && !defined(lint)
  46 #if 0
  47 static char sccsid[] = "@(#)strsep.c    8.1 (Berkeley) 6/4/93";
  48 #else
  49 static char *rcsid =
  50         "$OpenBSD: strsep.c,v 1.3 1997/08/20 04:28:14 millert Exp $";
  51 #endif
  52 #endif /* LIBC_SCCS and not lint */
  53
  54 /*
  55  * Get next token from string *stringp, where tokens are possibly-empty
  56  * strings separated by characters from delim.
  57  *
  58  * Writes NULs into the string at *stringp to end tokens.
  59  * delim need not remain constant from call to call.
  60  * On return, *stringp points past the last NUL written (if there might
  61  * be further tokens), or is NULL (if there are definitely no more tokens).
  62  *
  63  * If *stringp is NULL, strsep returns NULL.
  64  */
  65 char *
  66 strsep(char **stringp, const char *delim)
  67 {
  68         register char *s;
  69         register const char *spanp;
  70         register int c, sc;
  71         char *tok;
  72
  73         if ((s = *stringp) == NULL)
  74                 return (NULL);
  75         for (tok = s; ; ) {
  76                 c = *s++;
  77                 spanp = delim;
  78                 do {
  79                         if ((sc = *spanp++) == c) {
  80                                 if (c == 0)
  81                                         s = NULL;
  82                                 else
  83                                         s[-1] = 0;
  84                                 *stringp = s;
  85                                 return (tok);
  86                         }
  87                 } while (sc != 0);
  88         }
  89         /* NOTREACHED */
  90 }