stdlib.subproj/getsubopt.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * Copyright (c) 1990, 1993
  24  *      The Regents of the University of California.  All rights reserved.
  25  *
  26  * Redistribution and use in source and binary forms, with or without
  27  * modification, are permitted provided that the following conditions
  28  * are met:
  29  * 1. Redistributions of source code must retain the above copyright
  30  *    notice, this list of conditions and the following disclaimer.
  31  * 2. Redistributions in binary form must reproduce the above copyright
  32  *    notice, this list of conditions and the following disclaimer in the
  33  *    documentation and/or other materials provided with the distribution.
  34  * 3. All advertising materials mentioning features or use of this software
  35  *    must display the following acknowledgement:
  36  *      This product includes software developed by the University of
  37  *      California, Berkeley and its contributors.
  38  * 4. Neither the name of the University nor the names of its contributors
  39  *    may be used to endorse or promote products derived from this software
  40  *    without specific prior written permission.
  41  *
  42  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  43  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  44  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  45  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  46  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  47  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  48  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  49  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  50  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  51  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  52  * SUCH DAMAGE.
  53  */
  54
  55
  56 #include <unistd.h>
  57 #include <stdlib.h>
  58
  59 /*
  60  * The SVID interface to getsubopt provides no way of figuring out which
  61  * part of the suboptions list wasn't matched.  This makes error messages
  62  * tricky...  The extern variable suboptarg is a pointer to the token
  63  * which didn't match.
  64  */
  65 char *suboptarg;
  66
  67 getsubopt(optionp, tokens, valuep)
  68         register char **optionp, **valuep;
  69         register char * const *tokens;
  70 {
  71         register int cnt;
  72         register char *p;
  73
  74         suboptarg = *valuep = NULL;
  75
  76         if (!optionp || !*optionp)
  77                 return(-1);
  78
  79         /* skip leading white-space, commas */
  80         for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
  81
  82         if (!*p) {
  83                 *optionp = p;
  84                 return(-1);
  85         }
  86
  87         /* save the start of the token, and skip the rest of the token. */
  88         for (suboptarg = p;
  89             *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
  90
  91         if (*p) {
  92                 /*
  93                  * If there's an equals sign, set the value pointer, and
  94                  * skip over the value part of the token.  Terminate the
  95                  * token.
  96                  */
  97                 if (*p == '=') {
  98                         *p = '\0';
  99                         for (*valuep = ++p;
 100                             *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
 101                         if (*p)
 102                                 *p++ = '\0';
 103                 } else
 104                         *p++ = '\0';
 105                 /* Skip any whitespace or commas after this token. */
 106                 for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
 107         }
 108
 109         /* set optionp for next round. */
 110         *optionp = p;
 111
 112         for (cnt = 0; *tokens; ++tokens, ++cnt)
 113                 if (!strcmp(suboptarg, *tokens))
 114                         return(cnt);
 115         return(-1);
 116 }