misc/getdomain.c

   1 /* Copyright (C) 1994-2024 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    <https://www.gnu.org/licenses/>.  */
  17
  18 /* Put the name of the current YP domain in no more than LEN bytes of NAME.
  19    The result is null-terminated if LEN is large enough for the full
  20    name and the terminator.  */
  21
  22 #include <errno.h>
  23 #include <unistd.h>
  24 #include <sys/param.h>
  25 #include <sys/utsname.h>
  26 #include <string.h>
  27
  28 #if _UTSNAME_DOMAIN_LENGTH
  29 /* The `uname' information includes the domain name.  */
  30
  31 int
  32 getdomainname (char *name, size_t len)
  33 {
  34   struct utsname u;
  35   size_t u_len;
  36
  37   if (uname (&u) < 0)
  38     return -1;
  39
  40   u_len = strlen (u.domainname);
  41   memcpy (name, u.domainname, MIN (u_len + 1, len));
  42   return 0;
  43 }
  44
  45 #else
  46
  47 int
  48 getdomainname (char *name, size_t len)
  49 {
  50   __set_errno (ENOSYS);
  51   return -1;
  52 }
  53
  54 stub_warning (getdomainname)
  55
  56 #endif
  57
  58 libc_hidden_def (getdomainname)