sysdeps/unix/sysv/linux/makedev.c

   1 /* Definitions of functions to access `dev_t' values.
   2    Copyright (C) 2003 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <endian.h>
  21 #include <sys/sysmacros.h>
  22
  23 unsigned int
  24 gnu_dev_major (unsigned long long int dev)
  25 {
  26   return ((dev >> 8) & 0xfff) | ((unsigned int) (dev >> 32) & ~0xfff);
  27 }
  28
  29 unsigned int
  30 gnu_dev_minor (unsigned long long int dev)
  31 {
  32   return (dev & 0xff) | ((unsigned int) (dev >> 12) & ~0xff);
  33 }
  34
  35 unsigned long long int
  36 gnu_dev_makedev (unsigned int major, unsigned int minor)
  37 {
  38   return ((minor & 0xff) | ((major & 0xfff) << 8)
  39           | (((unsigned long long int) (minor & ~0xff)) << 12)
  40           | (((unsigned long long int) (major & ~0xfff)) << 32));
  41 }