xref: /netbsd/lib/libc/gen/gethostname.c (revision 6550d01e)
1 /*	$NetBSD: gethostname.c,v 1.12 2005/10/14 23:53:41 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 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 <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)gethostname.c	8.1 (Berkeley) 6/4/93";
36 #else
37 __RCSID("$NetBSD: gethostname.c,v 1.12 2005/10/14 23:53:41 christos Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include "namespace.h"
42 #include <sys/param.h>
43 #include <sys/sysctl.h>
44 
45 #include <assert.h>
46 #include <errno.h>
47 #include <unistd.h>
48 
49 #ifdef __weak_alias
50 __weak_alias(gethostname,_gethostname)
51 #endif
52 
53 int
54 gethostname(name, namelen)
55 	char *name;
56 	size_t namelen;
57 {
58 	int mib[2];
59 	size_t size;
60 
61 	_DIAGASSERT(name != NULL);
62 
63 	mib[0] = CTL_KERN;
64 	mib[1] = KERN_HOSTNAME;
65 	size = namelen;
66 	if (sysctl(mib, 2, name, &size, NULL, 0) == -1)
67 		return (-1);
68 
69 	return (0);
70 }
71