xref: /dflybsd-src/lib/libc/uuid/uuid_compare.c (revision 86d7f5d305c6adaa56ff4582ece9859d73106103)
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_compare.c,v 1.6 2007/04/05 02:07:33 delphij Exp $
28*86d7f5d3SJohn Marino  * $DragonFly: src/lib/libc/uuid/uuid_compare.c,v 1.1 2007/06/16 19:57:14 dillon Exp $
29*86d7f5d3SJohn Marino  */
30*86d7f5d3SJohn Marino 
31*86d7f5d3SJohn Marino #include <string.h>
32*86d7f5d3SJohn Marino #include <uuid.h>
33*86d7f5d3SJohn Marino 
34*86d7f5d3SJohn Marino /* A macro used to improve the readability of uuid_compare(). */
35*86d7f5d3SJohn Marino #define DIFF_RETURN(a, b, field)	do {			\
36*86d7f5d3SJohn Marino 	if ((a)->field != (b)->field)				\
37*86d7f5d3SJohn Marino 		return (((a)->field < (b)->field) ? -1 : 1);	\
38*86d7f5d3SJohn Marino } while (0)
39*86d7f5d3SJohn Marino 
40*86d7f5d3SJohn Marino /*
41*86d7f5d3SJohn Marino  * uuid_compare() - compare two UUIDs.
42*86d7f5d3SJohn Marino  * See also:
43*86d7f5d3SJohn Marino  *	http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm
44*86d7f5d3SJohn Marino  *
45*86d7f5d3SJohn Marino  * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller
46*86d7f5d3SJohn Marino  *	 than any non-nil UUID.
47*86d7f5d3SJohn Marino  */
48*86d7f5d3SJohn Marino int32_t
uuid_compare(const uuid_t * a,const uuid_t * b,uint32_t * status)49*86d7f5d3SJohn Marino uuid_compare(const uuid_t *a, const uuid_t *b, uint32_t *status)
50*86d7f5d3SJohn Marino {
51*86d7f5d3SJohn Marino 	int	res;
52*86d7f5d3SJohn Marino 
53*86d7f5d3SJohn Marino 	if (status != NULL)
54*86d7f5d3SJohn Marino 		*status = uuid_s_ok;
55*86d7f5d3SJohn Marino 
56*86d7f5d3SJohn Marino 	/* Deal with NULL or equal pointers. */
57*86d7f5d3SJohn Marino 	if (a == b)
58*86d7f5d3SJohn Marino 		return (0);
59*86d7f5d3SJohn Marino 	if (a == NULL)
60*86d7f5d3SJohn Marino 		return ((uuid_is_nil(b, NULL)) ? 0 : -1);
61*86d7f5d3SJohn Marino 	if (b == NULL)
62*86d7f5d3SJohn Marino 		return ((uuid_is_nil(a, NULL)) ? 0 : 1);
63*86d7f5d3SJohn Marino 
64*86d7f5d3SJohn Marino 	/* We have to compare the hard way. */
65*86d7f5d3SJohn Marino 	DIFF_RETURN(a, b, time_low);
66*86d7f5d3SJohn Marino 	DIFF_RETURN(a, b, time_mid);
67*86d7f5d3SJohn Marino 	DIFF_RETURN(a, b, time_hi_and_version);
68*86d7f5d3SJohn Marino 	DIFF_RETURN(a, b, clock_seq_hi_and_reserved);
69*86d7f5d3SJohn Marino 	DIFF_RETURN(a, b, clock_seq_low);
70*86d7f5d3SJohn Marino 
71*86d7f5d3SJohn Marino 	res = memcmp(a->node, b->node, sizeof(a->node));
72*86d7f5d3SJohn Marino 	if (res)
73*86d7f5d3SJohn Marino 		return ((res < 0) ? -1 : 1);
74*86d7f5d3SJohn Marino 	return (0);
75*86d7f5d3SJohn Marino }
76*86d7f5d3SJohn Marino 
77*86d7f5d3SJohn Marino #undef DIFF_RETURN
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