1/*	$NetBSD: subr_optstr.c,v 1.8 2023/04/20 09:04:45 skrll Exp $	*/
2
3/*-
4 * Copyright (c) 2006 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Julio M. Merino Vidal.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__KERNEL_RCSID(0, "$NetBSD: subr_optstr.c,v 1.8 2023/04/20 09:04:45 skrll Exp $");
34
35#include <sys/param.h>
36#include <sys/optstr.h>
37
38/* --------------------------------------------------------------------- */
39
40/*
41 * Given an options string of the form 'a=b c=d ... y=z' and a key,
42 * looks for the given key's value in the string and returns it in buf
43 * with a maximum of bufsize bytes.  If the key is found, returns true;
44 * otherwise FALSE.
45 */
46
47
48static bool
49optstr_get_pointer(const char *optstr, const char *key, const char **result)
50{
51	bool found = false;
52
53	/* Skip any initial spaces or tabs until we find a word. */
54	while (*optstr == ' ' || *optstr == '\t')
55		optstr++;
56
57	/* Search for the given key within the option string. */
58	while (!found && *optstr != '\0') {
59		const char *keyp;
60
61		/* Check if the next word matches the key. */
62		keyp = key;
63		while (*optstr == *keyp) {
64			optstr++;
65			keyp++;
66		}
67
68		if (*optstr == '=' && *keyp == '\0')
69			found = true;
70		else {
71			/* Key not found; skip until next space. */
72			while (*optstr != ' ' && *optstr != '\0')
73				optstr++;
74
75			/* And now skip until next word. */
76			while (*optstr == ' ')
77				optstr++;
78		}
79	}
80
81	if (found) {
82		optstr++; /* Skip '='. */
83		*result = optstr;
84	}
85
86	return found;
87}
88
89bool
90optstr_get(const char *optstr, const char *key, char *buf, size_t bufsize)
91{
92	const char *data;
93	bool found = optstr_get_pointer(optstr, key, &data);
94
95	/* If the key was found; copy its value to the target buffer. */
96	if (found) {
97		const char *lastbuf = buf + (bufsize - 1);
98
99		while (buf != lastbuf && *data != ' ' && *data != '\0')
100			*buf++ = *data++;
101		*buf = '\0';
102	}
103	return found;
104}
105
106
107bool
108optstr_get_string(const char *optstr, const char *key, const char **result)
109{
110	const char *data;
111	const bool found = optstr_get_pointer(optstr, key, &data);
112
113	/* If the key was found; copy its value to the target buffer. */
114	if (found) {
115		*result = data;
116	}
117	return found;
118}
119
120bool
121optstr_get_number(const char *optstr, const char *key, unsigned long *result)
122{
123	const char *data;
124	const bool found = optstr_get_pointer(optstr, key, &data);
125
126	/* If the key was found; copy its value to the target buffer. */
127	if (found) {
128		char *ep;
129		const unsigned long ulval = strtoul(data, &ep, 10);
130		if (ep == data)
131			return false;
132		*result = ulval;
133		return true;
134	}
135	return false;
136}
137
138bool
139optstr_get_number_hex(const char *optstr, const char *key,
140    unsigned long *result)
141{
142	const char *data;
143	const bool found = optstr_get_pointer(optstr, key, &data);
144
145	/* If the key was found; copy its value to the target buffer. */
146	if (found) {
147		char *ep;
148		const unsigned long ulval = strtoul(data, &ep, 16);
149		if (ep == data)
150			return false;
151		*result = ulval;
152		return true;
153	}
154	return false;
155}
156
157bool
158optstr_get_number_binary(const char *optstr, const char *key,
159    unsigned long *result)
160{
161	const char *data;
162	const bool found = optstr_get_pointer(optstr, key, &data);
163
164	/* If the key was found; copy its value to the target buffer. */
165	if (found) {
166		char *ep;
167		const unsigned long ulval = strtoul(data, &ep, 2);
168		if (ep == data)
169			return false;
170		*result = ulval;
171		return true;
172	}
173	return false;
174}
175
176
177#if NETHER > 0
178bool
179optstr_get_macaddr(const char *optstr, const char *key,
180    uint8_t result[ETHER_ADDR_LEN])
181{
182	const char *data;
183	const bool found = optstr_get_pointer(optstr, key, &data);
184
185	/* If the key was found; copy its value to the target buffer. */
186	if (found) {
187		uint8_t temp[ETHER_ADDR_LEN];
188		int error = ether_aton_r(temp, sizeof(temp), data);
189		if (error)
190			return false;
191		memcpy(result, temp, sizeof(temp));
192	}
193	return found;
194}
195#endif
196