1/*
2 * Copyright (c) 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)gethostname.c	8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: src/lib/libc/gen/gethostname.c,v 1.8 2007/01/09 00:27:54 imp Exp $");
35
36#include <string.h>
37#include <sys/param.h>
38#include <sys/sysctl.h>
39#include <limits.h>
40
41#include <errno.h>
42#include <unistd.h>
43
44int
45gethostname(name, namelen)
46	char *name;
47	size_t namelen;
48{
49	int mib[2];
50
51	mib[0] = CTL_KERN;
52	mib[1] = KERN_HOSTNAME;
53	if (namelen < MAXHOSTNAMELEN + 1) {
54		char local_buf[MAXHOSTNAMELEN + 1];
55		size_t local_len = sizeof(local_buf);
56		if (sysctl(mib, 2, local_buf, &local_len, NULL, 0) == -1) {
57			if (errno == ENOMEM)
58				errno = ENAMETOOLONG;
59			return (-1);
60		}
61		strncpy(name, local_buf, namelen);
62		name[namelen - 1] = 0;
63	} else {
64	if (sysctl(mib, 2, name, &namelen, NULL, 0) == -1) {
65		if (errno == ENOMEM)
66			errno = ENAMETOOLONG;
67		return (-1);
68		}
69	}
70	return (0);
71}
72