1 | /* $NetBSD: subr_optstr.c,v 1.6 2016/05/30 11:24:40 martin 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 1.6 2016/05/30 11:24:40 martin 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 | bool |
47 | optstr_get(const char *optstr, const char *key, char *buf, size_t bufsize) |
48 | { |
49 | bool found; |
50 | |
51 | found = false; |
52 | |
53 | /* Skip any initial spaces until we find a word. */ |
54 | while (*optstr == ' ') |
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 the key was found; copy its value to the target buffer. */ |
82 | if (found) { |
83 | const char *lastbuf; |
84 | |
85 | lastbuf = buf + (bufsize - 1); |
86 | |
87 | optstr++; /* Skip '='. */ |
88 | while (buf != lastbuf && *optstr != ' ' && *optstr != '\0') |
89 | *buf++ = *optstr++; |
90 | *buf = '\0'; |
91 | } |
92 | |
93 | return found; |
94 | } |
95 | |