glibc/sysdeps/unix/sysv/linux/sys/sysmacros.h
2011-05-07 09:13:43 -04:00

73 lines
2.4 KiB
C

/* Definitions of macros to access `dev_t' values.
Copyright (C) 1996, 1997, 1999, 2003, 2004, 2007, 2011
Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _SYS_SYSMACROS_H
#define _SYS_SYSMACROS_H 1
#include <features.h>
/* If the compiler does not know long long it is out of luck. We are
not going to hack weird hacks to support the dev_t representation
they need. */
#ifdef __GLIBC_HAVE_LONG_LONG
__BEGIN_DECLS
__extension__
extern unsigned int gnu_dev_major (unsigned long long int __dev)
__THROW;
__extension__
extern unsigned int gnu_dev_minor (unsigned long long int __dev)
__THROW;
__extension__
extern unsigned long long int gnu_dev_makedev (unsigned int __major,
unsigned int __minor)
__THROW;
# if defined __GNUC__ && __GNUC__ >= 2 && defined __USE_EXTERN_INLINES
__extension__ __extern_inline unsigned int
__NTH (gnu_dev_major (unsigned long long int __dev))
{
return ((__dev >> 8) & 0xfff) | ((unsigned int) (__dev >> 32) & ~0xfff);
}
__extension__ __extern_inline unsigned int
__NTH (gnu_dev_minor (unsigned long long int __dev))
{
return (__dev & 0xff) | ((unsigned int) (__dev >> 12) & ~0xff);
}
__extension__ __extern_inline unsigned long long int
__NTH (gnu_dev_makedev (unsigned int __major, unsigned int __minor))
{
return ((__minor & 0xff) | ((__major & 0xfff) << 8)
| (((unsigned long long int) (__minor & ~0xff)) << 12)
| (((unsigned long long int) (__major & ~0xfff)) << 32));
}
# endif
__END_DECLS
/* Access the functions with their traditional names. */
# define major(dev) gnu_dev_major (dev)
# define minor(dev) gnu_dev_minor (dev)
# define makedev(maj, min) gnu_dev_makedev (maj, min)
#endif
#endif /* sys/sysmacros.h */