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

   1 /* Copyright (C) 1998, 2000 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 <sys/types.h>
  21 #include <sys/fsuid.h>
  22
  23 #include <sysdep.h>
  24 #include <sys/syscall.h>
  25 #include <linux/posix_types.h>
  26 #include "kernel-features.h"
  27
  28
  29 #ifdef __NR_setfsgid
  30
  31 extern int __syscall_setfsgid (__kernel_gid_t);
  32
  33 # ifdef __NR_setfsgid32
  34 extern int __syscall_setfsgid32 (__kernel_gid32_t);
  35 #  if __ASSUME_32BITUIDS == 0
  36 /* This variable is shared with all files that need to check for 32bit
  37    uids.  */
  38 extern int __libc_missing_32bit_uids;
  39 #  endif
  40 # endif /* __NR_setfsgid32 */
  41
  42 int
  43 setfsgid (gid_t gid)
  44 {
  45 # if __ASSUME_32BITUIDS > 0
  46   return INLINE_SYSCALL (setfsgid32, 1, gid);
  47 # else
  48 #  ifdef __NR_setfsgid32
  49   if (__libc_missing_32bit_uids <= 0)
  50     {
  51       int result;
  52       int saved_errno = errno;
  53
  54       result = INLINE_SYSCALL (setfsgid32, 1, gid);
  55       if (result == 0 || errno != ENOSYS)
  56         return result;
  57
  58       __set_errno (saved_errno);
  59       __libc_missing_32bit_uids = 1;
  60     }
  61 #  endif /* __NR_setfsgid32 */
  62   if (gid != (gid_t) ((__kernel_gid_t) gid))
  63     {
  64       __set_errno (EINVAL);
  65       return -1;
  66     }
  67
  68   return INLINE_SYSCALL (setfsgid, 1, gid);
  69 # endif
  70 }
  71 #endif