sysdeps/unix/sysv/linux/i386/setresgid.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 <unistd.h>
  21 #include <sys/types.h>
  22
  23 #include <linux/posix_types.h>
  24
  25 #include <sysdep.h>
  26 #include <sys/syscall.h>
  27 #include "kernel-features.h"
  28
  29 #ifdef __NR_setresgid
  30
  31 extern int __syscall_setresgid (__kernel_gid_t rgid, __kernel_gid_t egid,
  32                                 __kernel_gid_t sgid);
  33
  34 # ifdef __NR_setresgid32
  35 extern int __syscall_setresgid32 (__kernel_gid32_t rgid, __kernel_gid32_t egid,
  36                                   __kernel_gid32_t sgid);
  37 #  if __ASSUME_32BITUIDS == 0
  38 /* This variable is shared with all files that need to check for 32bit
  39    uids.  */
  40 extern int __libc_missing_32bit_uids;
  41 #  endif
  42 # endif /* __NR_setresgid32 */
  43
  44 extern int setresgid (gid_t rgid, gid_t egid, gid_t sgid);
  45
  46 int
  47 setresgid (gid_t rgid, gid_t egid, gid_t sgid)
  48 {
  49 # if __ASSUME_32BITUIDS > 0
  50   return INLINE_SYSCALL (setresgid32, 3, rgid, egid, sgid);
  51 # else
  52 #  ifdef __NR_setresgid32
  53   if (__libc_missing_32bit_uids <= 0)
  54     {
  55       int result;
  56       int saved_errno = errno;
  57
  58       result = INLINE_SYSCALL (setresgid32, 3, rgid, egid, sgid);
  59       if (result == 0 || errno != ENOSYS)
  60         return result;
  61
  62       __set_errno (saved_errno);
  63       __libc_missing_32bit_uids = 1;
  64     }
  65 #  endif /* __NR_setresgid32 */
  66
  67   if (((rgid + 1) > (gid_t) ((__kernel_gid_t) -1U))
  68       || ((egid + 1) > (gid_t) ((__kernel_gid_t) -1U))
  69       || ((sgid + 1) > (gid_t) ((__kernel_gid_t) -1U)))
  70     {
  71       __set_errno (EINVAL);
  72       return -1;
  73     }
  74
  75   return INLINE_SYSCALL (setresgid, 3, rgid, egid, sgid);
  76 # endif
  77 }
  78 #endif