sysdeps/unix/sysv/linux/i386/geteuid.c

   1 /* Copyright (C) 2000, 2003, 2006 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, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <errno.h>
  20 #include <unistd.h>
  21
  22 #include <sysdep.h>
  23 #include <sys/syscall.h>
  24 #include <kernel-features.h>
  25
  26 #ifdef __NR_geteuid32
  27 # if __ASSUME_32BITUIDS == 0
  28 /* This variable is shared with all files that need to check for 32bit
  29    uids.  */
  30 extern int __libc_missing_32bit_uids attribute_hidden;
  31 # endif
  32 #endif /* __NR_geteuid32 */
  33
  34 uid_t
  35 __geteuid (void)
  36 {
  37   INTERNAL_SYSCALL_DECL (err);
  38 #if __ASSUME_32BITUIDS > 0
  39   /* No error checking.  */
  40   return INTERNAL_SYSCALL (geteuid32, err, 0);
  41 #else
  42 # ifdef __NR_geteuid32
  43   if (__libc_missing_32bit_uids <= 0)
  44     {
  45       int result;
  46
  47       result = INTERNAL_SYSCALL (geteuid32, err, 0);
  48       if (! INTERNAL_SYSCALL_ERROR_P (result, err)
  49           || INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS)
  50         return result;
  51
  52       __libc_missing_32bit_uids = 1;
  53     }
  54 # endif /* __NR_geteuid32 */
  55
  56   /* No error checking.  */
  57   return INTERNAL_SYSCALL (geteuid, err, 0);
  58 #endif
  59 }
  60
  61 weak_alias (__geteuid, geteuid)