sysdeps/unix/sysv/linux/xmknodat.c

   1 /* Copyright (C) 2005-2015 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 <fcntl.h>
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <sys/sysmacros.h>
  25
  26 #include <sysdep.h>
  27 #include <sys/syscall.h>
  28
  29
  30 /* Create a device file named PATH relative to FD, with permission and
  31    special bits MODE and device number DEV (which can be constructed
  32    from major and minor device numbers with the `makedev' macro above).  */
  33 int
  34 __xmknodat (int vers, int fd, const char *file, mode_t mode, dev_t *dev)
  35 {
  36   if (vers != _MKNOD_VER)
  37     {
  38       __set_errno (EINVAL);
  39       return -1;
  40     }
  41
  42   /* We must convert the value to dev_t type used by the kernel.  */
  43   unsigned long long int k_dev =  (*dev) & ((1ULL << 32) - 1);
  44   if (k_dev != *dev)
  45     {
  46       __set_errno (EINVAL);
  47       return -1;
  48     }
  49
  50   return INLINE_SYSCALL (mknodat, 4, fd, file, mode, (unsigned int) k_dev);
  51 }
  52
  53 libc_hidden_def (__xmknodat)