| 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 | |