Blame view

fs/xfs/uuid.c 1.64 KB
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
1
  /*
7b7187698   Nathan Scott   [XFS] Update lice...
2
3
   * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   * All Rights Reserved.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
4
   *
7b7187698   Nathan Scott   [XFS] Update lice...
5
6
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
7
8
   * published by the Free Software Foundation.
   *
7b7187698   Nathan Scott   [XFS] Update lice...
9
10
11
12
   * This program is distributed in the hope that it would 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.
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
13
   *
7b7187698   Nathan Scott   [XFS] Update lice...
14
15
16
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write the Free Software Foundation,
   * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
17
   */
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
18
  #include <xfs.h>
794fe2dc6   Christoph Hellwig   [XFS] endianess a...
19
20
21
22
23
24
25
26
  /* IRIX interpretation of an uuid_t */
  typedef struct {
  	__be32	uu_timelow;
  	__be16	uu_timemid;
  	__be16	uu_timehi;
  	__be16	uu_clockseq;
  	__be16	uu_node[3];
  } xfs_uu_t;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
27
28
29
30
31
32
33
34
35
  /*
   * uuid_getnodeuniq - obtain the node unique fields of a UUID.
   *
   * This is not in any way a standard or condoned UUID function;
   * it just something that's needed for user-level file handles.
   */
  void
  uuid_getnodeuniq(uuid_t *uuid, int fsid [2])
  {
794fe2dc6   Christoph Hellwig   [XFS] endianess a...
36
  	xfs_uu_t *uup = (xfs_uu_t *)uuid;
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
37

794fe2dc6   Christoph Hellwig   [XFS] endianess a...
38
39
  	fsid[0] = (be16_to_cpu(uup->uu_clockseq) << 16) |
  		   be16_to_cpu(uup->uu_timemid);
a780143ea   Nathan Scott   [XFS] UUID endian...
40
  	fsid[1] = be32_to_cpu(uup->uu_timelow);
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
41
  }
1da177e4c   Linus Torvalds   Linux-2.6.12-rc2
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
  int
  uuid_is_nil(uuid_t *uuid)
  {
  	int	i;
  	char	*cp = (char *)uuid;
  
  	if (uuid == NULL)
  		return 0;
  	/* implied check of version number here... */
  	for (i = 0; i < sizeof *uuid; i++)
  		if (*cp++) return 0;	/* not nil */
  	return 1;	/* is nil */
  }
  
  int
  uuid_equal(uuid_t *uuid1, uuid_t *uuid2)
  {
  	return memcmp(uuid1, uuid2, sizeof(uuid_t)) ? 0 : 1;
  }