sysdeps/unix/sysv/linux/xmknod.c

   1 /* xmknod call using old-style Unix mknod system call.
   2    Copyright (C) 1991-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <sys/sysmacros.h>
  23
  24 #include <sysdep.h>
  25 #include <sys/syscall.h>
  26
  27 /* Create a device file named PATH, with permission and special bits MODE
  28    and device number DEV (which can be constructed from major and minor
  29    device numbers with the `makedev' macro above).  */
  30 int
  31 __xmknod (int vers, const char *path, mode_t mode, dev_t *dev)
  32 {
  33   unsigned long long int k_dev;
  34
  35   if (vers != _MKNOD_VER)
  36     {
  37       __set_errno (EINVAL);
  38       return -1;
  39     }
  40
  41   /* We must convert the value to dev_t type used by the kernel.  */
  42   k_dev =  (*dev) & ((1ULL << 32) - 1);
  43   if (k_dev != *dev)
  44     {
  45       __set_errno (EINVAL);
  46       return -1;
  47     }
  48
  49   return INLINE_SYSCALL (mknod, 3, path, mode, (unsigned int) k_dev);
  50 }
  51
  52 weak_alias (__xmknod, _xmknod)
  53 libc_hidden_def (__xmknod)