1/*	$OpenBSD: getsubopt.c,v 1.4 2005/08/08 08:05:36 espie Exp $	*/
2
3/*-
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <unistd.h>
33#include <stdlib.h>
34#include <string.h>
35
36/*
37 * The SVID interface to getsubopt provides no way of figuring out which
38 * part of the suboptions list wasn't matched.  This makes error messages
39 * tricky...  The extern variable suboptarg is a pointer to the token
40 * which didn't match.
41 */
42char *suboptarg;
43
44int
45getsubopt(char **optionp, char * const *tokens, char **valuep)
46{
47	int cnt;
48	char *p;
49
50	suboptarg = *valuep = NULL;
51
52	if (!optionp || !*optionp)
53		return(-1);
54
55	/* skip leading white-space, commas */
56	for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
57
58	if (!*p) {
59		*optionp = p;
60		return(-1);
61	}
62
63	/* save the start of the token, and skip the rest of the token. */
64	for (suboptarg = p;
65	    *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
66
67	if (*p) {
68		/*
69		 * If there's an equals sign, set the value pointer, and
70		 * skip over the value part of the token.  Terminate the
71		 * token.
72		 */
73		if (*p == '=') {
74			*p = '\0';
75			for (*valuep = ++p;
76			    *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
77			if (*p)
78				*p++ = '\0';
79		} else
80			*p++ = '\0';
81		/* Skip any whitespace or commas after this token. */
82		for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
83	}
84
85	/* set optionp for next round. */
86	*optionp = p;
87
88	for (cnt = 0; *tokens; ++tokens, ++cnt)
89		if (!strcmp(suboptarg, *tokens))
90			return(cnt);
91	return(-1);
92}
93