nagios-plugins/gl/gethostname.c

/* gethostname emulation for SysV and POSIX.1.

   Copyright (C) 1992, 2003, 2006, 2008 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* David MacKenzie <djm@gnu.ai.mit.edu> */

#include <config.h>

/* Specification.  */
#include <unistd.h>

#ifdef HAVE_UNAME
# include <sys/utsname.h>
#endif

#include <string.h>

/* Put up to LEN chars of the host name into NAME.
   Null terminate it if the name is shorter than LEN.
   Return 0 if ok, -1 if error.  */

#include <stddef.h>

int
gethostname (char *name, size_t len)
{
#ifdef HAVE_UNAME
  struct utsname uts;

  if (uname (&uts) == -1)
    return -1;
  if (len > sizeof (uts.nodename))
    {
      /* More space than we need is available.  */
      name[sizeof (uts.nodename)] = '\0';
      len = sizeof (uts.nodename);
    }
  strncpy (name, uts.nodename, len);
#else
  strcpy (name, "");		/* Hardcode your system name if you want.  */
#endif
  return 0;
}