getsubopt.c revision 17141 
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#ifndef lint
35static char sccsid[] = "@(#)getsubopt.c	8.1 (Berkeley) 6/4/93";
36#endif /* not lint */
37
38#include <unistd.h>
39#include <stdlib.h>
40
41/*
42 * The SVID interface to getsubopt provides no way of figuring out which
43 * part of the suboptions list wasn't matched.  This makes error messages
44 * tricky...  The extern variable suboptarg is a pointer to the token
45 * which didn't match.
46 */
47char *suboptarg;
48
49int
50getsubopt(optionp, tokens, valuep)
51	register char **optionp, **valuep;
52	register char * const *tokens;
53{
54	register int cnt;
55	register char *p;
56
57	suboptarg = *valuep = NULL;
58
59	if (!optionp || !*optionp)
60		return(-1);
61
62	/* skip leading white-space, commas */
63	for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
64
65	if (!*p) {
66		*optionp = p;
67		return(-1);
68	}
69
70	/* save the start of the token, and skip the rest of the token. */
71	for (suboptarg = p;
72	    *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
73
74	if (*p) {
75		/*
76		 * If there's an equals sign, set the value pointer, and
77		 * skip over the value part of the token.  Terminate the
78		 * token.
79		 */
80		if (*p == '=') {
81			*p = '\0';
82			for (*valuep = ++p;
83			    *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
84			if (*p)
85				*p++ = '\0';
86		} else
87			*p++ = '\0';
88		/* Skip any whitespace or commas after this token. */
89		for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
90	}
91
92	/* set optionp for next round. */
93	*optionp = p;
94
95	for (cnt = 0; *tokens; ++tokens, ++cnt)
96		if (!strcmp(suboptarg, *tokens))
97			return(cnt);
98	return(-1);
99}
100