stdlib/FreeBSD/getsubopt.c

   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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)getsubopt.c 8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD: src/lib/libc/stdlib/getsubopt.c,v 1.5 2003/01/03 23:31:50 tjr Exp $");
  39
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43
  44 /*
  45  * The SVID interface to getsubopt provides no way of figuring out which
  46  * part of the suboptions list wasn't matched.  This makes error messages
  47  * tricky...  The extern variable suboptarg is a pointer to the token
  48  * which didn't match.
  49  */
  50 char *suboptarg;
  51
  52 int
  53 getsubopt(optionp, tokens, valuep)
  54         char **optionp, **valuep;
  55         char * const *tokens;
  56 {
  57         int cnt;
  58         char *p;
  59
  60         suboptarg = *valuep = NULL;
  61
  62         if (!optionp || !*optionp)
  63                 return(-1);
  64
  65         /* skip leading white-space, commas */
  66         for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
  67
  68         if (!*p) {
  69                 *optionp = p;
  70                 return(-1);
  71         }
  72
  73         /* save the start of the token, and skip the rest of the token. */
  74         for (suboptarg = p;
  75             *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
  76
  77         if (*p) {
  78                 /*
  79                  * If there's an equals sign, set the value pointer, and
  80                  * skip over the value part of the token.  Terminate the
  81                  * token.
  82                  */
  83                 if (*p == '=') {
  84                         *p = '\0';
  85                         for (*valuep = ++p;
  86                             *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
  87                         if (*p)
  88                                 *p++ = '\0';
  89                 } else
  90                         *p++ = '\0';
  91                 /* Skip any whitespace or commas after this token. */
  92                 for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
  93         }
  94
  95         /* set optionp for next round. */
  96         *optionp = p;
  97
  98         for (cnt = 0; *tokens; ++tokens, ++cnt)
  99                 if (!strcmp(suboptarg, *tokens))
 100                         return(cnt);
 101         return(-1);
 102 }