stdlib/getsubopt.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * Copyright (c) 1990, 1993
  27  *      The Regents of the University of California.  All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  */
  57
  58
  59 #include <unistd.h>
  60 #include <stdlib.h>
  61
  62 /*
  63  * The SVID interface to getsubopt provides no way of figuring out which
  64  * part of the suboptions list wasn't matched.  This makes error messages
  65  * tricky...  The extern variable suboptarg is a pointer to the token
  66  * which didn't match.
  67  */
  68 char *suboptarg;
  69
  70 getsubopt(optionp, tokens, valuep)
  71         register char **optionp, **valuep;
  72         register char * const *tokens;
  73 {
  74         register int cnt;
  75         register char *p;
  76
  77         suboptarg = *valuep = NULL;
  78
  79         if (!optionp || !*optionp)
  80                 return(-1);
  81
  82         /* skip leading white-space, commas */
  83         for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
  84
  85         if (!*p) {
  86                 *optionp = p;
  87                 return(-1);
  88         }
  89
  90         /* save the start of the token, and skip the rest of the token. */
  91         for (suboptarg = p;
  92             *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
  93
  94         if (*p) {
  95                 /*
  96                  * If there's an equals sign, set the value pointer, and
  97                  * skip over the value part of the token.  Terminate the
  98                  * token.
  99                  */
 100                 if (*p == '=') {
 101                         *p = '\0';
 102                         for (*valuep = ++p;
 103                             *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
 104                         if (*p)
 105                                 *p++ = '\0';
 106                 } else
 107                         *p++ = '\0';
 108                 /* Skip any whitespace or commas after this token. */
 109                 for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
 110         }
 111
 112         /* set optionp for next round. */
 113         *optionp = p;
 114
 115         for (cnt = 0; *tokens; ++tokens, ++cnt)
 116                 if (!strcmp(suboptarg, *tokens))
 117                         return(cnt);
 118         return(-1);
 119 }