linux-stable/lib/uuid.c
Huang Ying fab1c23242 Unified UUID/GUID definition
There are many different UUID/GUID definitions in kernel, such as that
in EFI, many file systems, some drivers, etc. Every kernel components
need UUID/GUID has its own definition. This patch provides a unified
definition for UUID/GUID.

UUID is defined via typedef. This makes that UUID appears more like a
preliminary type, and makes the data type explicit (comparing with
implicit "u8 uuid[16]").

The binary representation of UUID/GUID can be little-endian (used by
EFI, etc) or big-endian (defined by RFC4122), so both is defined.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2010-05-19 22:40:47 -04:00

53 lines
1.4 KiB
C

/*
* Unified UUID/GUID definition
*
* Copyright (C) 2009, Intel Corp.
* Huang Ying <ying.huang@intel.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation;
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/uuid.h>
#include <linux/random.h>
static void __uuid_gen_common(__u8 b[16])
{
int i;
u32 r;
for (i = 0; i < 4; i++) {
r = random32();
memcpy(b + i * 4, &r, 4);
}
/* reversion 0b10 */
b[8] = (b[8] & 0x3F) | 0x80;
}
void uuid_le_gen(uuid_le *lu)
{
__uuid_gen_common(lu->b);
/* version 4 : random generation */
lu->b[7] = (lu->b[7] & 0x0F) | 0x40;
}
EXPORT_SYMBOL_GPL(uuid_le_gen);
void uuid_be_gen(uuid_be *bu)
{
__uuid_gen_common(bu->b);
/* version 4 : random generation */
bu->b[6] = (bu->b[6] & 0x0F) | 0x40;
}
EXPORT_SYMBOL_GPL(uuid_be_gen);