/*      $NetBSD: getdomainname.c,v 1.13 2012/06/25 22:32:43 abs Exp $   */

/*
* Copyright (c) 1989, 1993
*      The Regents of the University of California.  All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)gethostname.c       8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: getdomainname.c,v 1.13 2012/06/25 22:32:43 abs Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#include "namespace.h"
#include <sys/param.h>
#include <sys/sysctl.h>

#include <assert.h>
#include <errno.h>
#include <unistd.h>

#ifdef __weak_alias
__weak_alias(getdomainname,_getdomainname)
#endif

int
getdomainname(char *name, size_t namelen)
{
       int mib[2];
       size_t size;
       int olderrno;

       _DIAGASSERT(name != NULL);

       mib[0] = CTL_KERN;
       mib[1] = KERN_DOMAINNAME;
       size = namelen;
       olderrno = errno;
       if (sysctl(mib, 2, name, &size, NULL, 0) == -1) {
               if (errno == ENOMEM) {
                       errno = olderrno;
                       return (0);
               }
               return (-1);
       }

       return (0);
}