xref: /freebsd/contrib/mandoc/compat_getsubopt.c (revision a466cc55373fc3cf86837f09da729535b57e69a1)
1 /*	$Id: compat_getsubopt.c,v 1.6 2020/06/15 01:37:15 schwarze Exp $ */
2 /*	$OpenBSD: getsubopt.c,v 1.4 2005/08/08 08:05:36 espie Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 #include "config.h"
33 
34 #include <unistd.h>
35 #include <stdlib.h>
36 #include <string.h>
37 
38 int
39 getsubopt(char **optionp, char * const *tokens, char **valuep)
40 {
41 	int cnt;
42 	char *suboptarg;
43 	char *p;
44 
45 	suboptarg = *valuep = NULL;
46 
47 	if (!optionp || !*optionp)
48 		return(-1);
49 
50 	/* skip leading white-space, commas */
51 	for (p = *optionp; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
52 
53 	if (!*p) {
54 		*optionp = p;
55 		return(-1);
56 	}
57 
58 	/* save the start of the token, and skip the rest of the token. */
59 	for (suboptarg = p;
60 	    *++p && *p != ',' && *p != '=' && *p != ' ' && *p != '\t';);
61 
62 	if (*p) {
63 		/*
64 		 * If there's an equals sign, set the value pointer, and
65 		 * skip over the value part of the token.  Terminate the
66 		 * token.
67 		 */
68 		if (*p == '=') {
69 			*p = '\0';
70 			for (*valuep = ++p;
71 			    *p && *p != ',' && *p != ' ' && *p != '\t'; ++p);
72 			if (*p)
73 				*p++ = '\0';
74 		} else
75 			*p++ = '\0';
76 		/* Skip any whitespace or commas after this token. */
77 		for (; *p && (*p == ',' || *p == ' ' || *p == '\t'); ++p);
78 	}
79 
80 	/* set optionp for next round. */
81 	*optionp = p;
82 
83 	for (cnt = 0; *tokens; ++tokens, ++cnt)
84 		if (!strcmp(suboptarg, *tokens))
85 			return(cnt);
86 	return(-1);
87 }
88