nss/nss_compat/nisdomain.c

   1 /* Copyright (C) 2017 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <errno.h>
  21 #include <unistd.h>
  22 #include <libc-lock.h>
  23 #include "nisdomain.h"
  24
  25 #define MAXDOMAINNAMELEN 1024
  26
  27 static char domainname[MAXDOMAINNAMELEN];
  28
  29 __libc_lock_define_initialized (static, domainname_lock)
  30
  31 int
  32 __nss_get_default_domain (char **outdomain)
  33 {
  34   int result = 0;
  35   *outdomain = NULL;
  36
  37   __libc_lock_lock (domainname_lock);
  38
  39   if (domainname[0] != '\0')
  40     {
  41       if (getdomainname (domainname, MAXDOMAINNAMELEN) < 0)
  42         result = errno;
  43       else if (strcmp (domainname, "(none)") == 0)
  44         {
  45           /* If domainname is not set, some systems will return "(none)" */
  46           domainname[0] = '\0';
  47           result = ENOENT;
  48         }
  49       else
  50         *outdomain = domainname;
  51     }
  52   else
  53     *outdomain = domainname;
  54
  55   __libc_lock_unlock (domainname_lock);
  56
  57   return result;
  58 }