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

   1 /* Copyright (C) 1998,2000,2002,2003,2005,2006 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, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <errno.h>
  19 #include <unistd.h>
  20 #include <sys/types.h>
  21
  22 #include <linux/posix_types.h>
  23
  24 #include <sysdep.h>
  25 #include <sys/syscall.h>
  26 #include <bp-checks.h>
  27
  28 #include <kernel-features.h>
  29
  30 #ifdef __NR_getresuid
  31
  32 # ifdef __NR_getresuid32
  33 #  if __ASSUME_32BITUIDS == 0
  34 /* This variable is shared with all files that need to check for 32bit
  35    uids.  */
  36 extern int __libc_missing_32bit_uids;
  37 #  endif
  38 # endif /* __NR_getresuid32 */
  39
  40 int
  41 __getresuid (uid_t *ruid, uid_t *euid, uid_t *suid)
  42 {
  43 # if __ASSUME_32BITUIDS > 0
  44   return INLINE_SYSCALL (getresuid32, 3, CHECK_1 (ruid),
  45                          CHECK_1 (euid), CHECK_1 (suid));
  46 # else
  47   __kernel_uid_t k_ruid, k_euid, k_suid;
  48   int result;
  49 #  ifdef __NR_getresuid32
  50   if (__libc_missing_32bit_uids <= 0)
  51     {
  52       int r;
  53       int saved_errno = errno;
  54
  55       r = INLINE_SYSCALL (getresuid32, 3, CHECK_1 (ruid),
  56                           CHECK_1 (euid), CHECK_1 (suid));
  57       if (r == 0 || errno != ENOSYS)
  58         return r;
  59
  60       __set_errno (saved_errno);
  61       __libc_missing_32bit_uids = 1;
  62     }
  63 #  endif /* __NR_getresuid32 */
  64
  65   result = INLINE_SYSCALL (getresuid, 3, __ptrvalue (&k_ruid),
  66                            __ptrvalue (&k_euid), __ptrvalue (&k_suid));
  67
  68   if (result == 0)
  69     {
  70       *ruid = (uid_t) k_ruid;
  71       *euid = (uid_t) k_euid;
  72       *suid = (uid_t) k_suid;
  73     }
  74
  75   return result;
  76 # endif
  77 }
  78 libc_hidden_def (__getresuid)
  79 weak_alias (__getresuid, getresuid)
  80
  81 #else
  82 # include <posix/getresuid.c>
  83 #endif