1*86d7f5d3SJohn Marino /*-
2*86d7f5d3SJohn Marino * Copyright (c) 2002,2005 Marcel Moolenaar
3*86d7f5d3SJohn Marino * Copyright (c) 2002 Hiten Mahesh Pandya
4*86d7f5d3SJohn Marino * All rights reserved.
5*86d7f5d3SJohn Marino *
6*86d7f5d3SJohn Marino * Redistribution and use in source and binary forms, with or without
7*86d7f5d3SJohn Marino * modification, are permitted provided that the following conditions
8*86d7f5d3SJohn Marino * are met:
9*86d7f5d3SJohn Marino * 1. Redistributions of source code must retain the above copyright
10*86d7f5d3SJohn Marino * notice, this list of conditions and the following disclaimer.
11*86d7f5d3SJohn Marino * 2. Redistributions in binary form must reproduce the above copyright
12*86d7f5d3SJohn Marino * notice, this list of conditions and the following disclaimer in the
13*86d7f5d3SJohn Marino * documentation and/or other materials provided with the distribution.
14*86d7f5d3SJohn Marino *
15*86d7f5d3SJohn Marino * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16*86d7f5d3SJohn Marino * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17*86d7f5d3SJohn Marino * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18*86d7f5d3SJohn Marino * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19*86d7f5d3SJohn Marino * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20*86d7f5d3SJohn Marino * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21*86d7f5d3SJohn Marino * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22*86d7f5d3SJohn Marino * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23*86d7f5d3SJohn Marino * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24*86d7f5d3SJohn Marino * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25*86d7f5d3SJohn Marino * SUCH DAMAGE.
26*86d7f5d3SJohn Marino *
27*86d7f5d3SJohn Marino * $FreeBSD: src/lib/libc/uuid/uuid_hash.c,v 1.3 2005/01/03 02:56:15 marcel Exp $
28*86d7f5d3SJohn Marino * $DragonFly: src/lib/libc/uuid/uuid_hash.c,v 1.1 2007/06/16 19:57:14 dillon Exp $
29*86d7f5d3SJohn Marino */
30*86d7f5d3SJohn Marino
31*86d7f5d3SJohn Marino #include <uuid.h>
32*86d7f5d3SJohn Marino
33*86d7f5d3SJohn Marino /*
34*86d7f5d3SJohn Marino * uuid_hash() - generate a hash value.
35*86d7f5d3SJohn Marino * See also:
36*86d7f5d3SJohn Marino * http://www.opengroup.org/onlinepubs/009629399/uuid_hash.htm
37*86d7f5d3SJohn Marino */
38*86d7f5d3SJohn Marino uint16_t
uuid_hash(const uuid_t * u,uint32_t * status)39*86d7f5d3SJohn Marino uuid_hash(const uuid_t *u, uint32_t *status)
40*86d7f5d3SJohn Marino {
41*86d7f5d3SJohn Marino
42*86d7f5d3SJohn Marino if (status)
43*86d7f5d3SJohn Marino *status = uuid_s_ok;
44*86d7f5d3SJohn Marino
45*86d7f5d3SJohn Marino /*
46*86d7f5d3SJohn Marino * Use the most frequently changing bits in the UUID as the hash
47*86d7f5d3SJohn Marino * value. This should yield a good enough distribution...
48*86d7f5d3SJohn Marino */
49*86d7f5d3SJohn Marino return ((u) ? u->time_low & 0xffff : 0);
50*86d7f5d3SJohn Marino }
51