gl/gethostname.c

   1 /* gethostname emulation for SysV and POSIX.1.
   2
   3    Copyright (C) 1992, 2003, 2006, 2008 Free Software Foundation, Inc.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 /* David MacKenzie <djm@gnu.ai.mit.edu> */
  19
  20 #include <config.h>
  21
  22 /* Specification.  */
  23 #include <unistd.h>
  24
  25 #ifdef HAVE_UNAME
  26 # include <sys/utsname.h>
  27 #endif
  28
  29 #include <string.h>
  30
  31 /* Put up to LEN chars of the host name into NAME.
  32    Null terminate it if the name is shorter than LEN.
  33    Return 0 if ok, -1 if error.  */
  34
  35 #include <stddef.h>
  36
  37 int
  38 gethostname (char *name, size_t len)
  39 {
  40 #ifdef HAVE_UNAME
  41   struct utsname uts;
  42
  43   if (uname (&uts) == -1)
  44     return -1;
  45   if (len > sizeof (uts.nodename))
  46     {
  47       /* More space than we need is available.  */
  48       name[sizeof (uts.nodename)] = '\0';
  49       len = sizeof (uts.nodename);
  50     }
  51   strncpy (name, uts.nodename, len);
  52 #else
  53   strcpy (name, "");            /* Hardcode your system name if you want.  */
  54 #endif
  55   return 0;
  56 }