Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[linux-btrfs-devel.git] / fs / xfs / uuid.c
blobb83f76b6d4106d87928bc0c69c4d8be0d169d168
1 /*
2 * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 #include <xfs.h>
20 /* IRIX interpretation of an uuid_t */
21 typedef struct {
22 __be32 uu_timelow;
23 __be16 uu_timemid;
24 __be16 uu_timehi;
25 __be16 uu_clockseq;
26 __be16 uu_node[3];
27 } xfs_uu_t;
30 * uuid_getnodeuniq - obtain the node unique fields of a UUID.
32 * This is not in any way a standard or condoned UUID function;
33 * it just something that's needed for user-level file handles.
35 void
36 uuid_getnodeuniq(uuid_t *uuid, int fsid [2])
38 xfs_uu_t *uup = (xfs_uu_t *)uuid;
40 fsid[0] = (be16_to_cpu(uup->uu_clockseq) << 16) |
41 be16_to_cpu(uup->uu_timemid);
42 fsid[1] = be32_to_cpu(uup->uu_timelow);
45 int
46 uuid_is_nil(uuid_t *uuid)
48 int i;
49 char *cp = (char *)uuid;
51 if (uuid == NULL)
52 return 0;
53 /* implied check of version number here... */
54 for (i = 0; i < sizeof *uuid; i++)
55 if (*cp++) return 0; /* not nil */
56 return 1; /* is nil */
59 int
60 uuid_equal(uuid_t *uuid1, uuid_t *uuid2)
62 return memcmp(uuid1, uuid2, sizeof(uuid_t)) ? 0 : 1;