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

   1 /* Copyright (C) 1998, 2000, 2002, 2003, 2004 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 #include <setxid.h>
  22 #include "kernel-features.h"
  23
  24
  25 #if defined __NR_setresuid || defined __NR_setresuid32
  26
  27 # ifdef __NR_setresuid32
  28 #  if __ASSUME_32BITUIDS == 0
  29 /* This variable is shared with all files that need to check for 32bit
  30    uids.  */
  31 extern int __libc_missing_32bit_uids;
  32 #  endif
  33 # endif /* __NR_setresuid32 */
  34
  35 int
  36 __setresuid (uid_t ruid, uid_t euid, uid_t suid)
  37 {
  38   int result;
  39
  40 # if __ASSUME_32BITUIDS > 0 || !defined __NR_setresuid
  41   result = INLINE_SETXID_SYSCALL (setresuid32, 3, ruid, euid, suid);
  42 # else
  43 #  ifdef __NR_setresuid32
  44   if (__libc_missing_32bit_uids <= 0)
  45     {
  46       int saved_errno = errno;
  47
  48       result = INLINE_SETXID_SYSCALL (setresuid32, 3, ruid, euid, suid);
  49       if (result == 0)
  50         goto out;
  51       if (errno != ENOSYS)
  52         return result;
  53
  54       __set_errno (saved_errno);
  55       __libc_missing_32bit_uids = 1;
  56     }
  57 #  endif /* __NR_setresuid32 */
  58
  59   if (((ruid + 1) > (uid_t) ((__kernel_uid_t) -1U))
  60       || ((euid + 1) > (uid_t) ((__kernel_uid_t) -1U))
  61       || ((suid + 1) > (uid_t) ((__kernel_uid_t) -1U)))
  62     {
  63       __set_errno (EINVAL);
  64       return -1;
  65     }
  66
  67   result = INLINE_SETXID_SYSCALL (setresuid, 3, ruid, euid, suid);
  68 #  ifdef __NR_setresuid32
  69  out:
  70 #  endif
  71 # endif
  72
  73   return result;
  74 }
  75 libc_hidden_def (__setresuid)
  76 #ifndef __setresuid
  77 weak_alias (__setresuid, setresuid)
  78 #endif
  79
  80 #else
  81
  82 #include <sysdeps/generic/setresuid.c>
  83
  84 #endif