1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2002,2005 Marcel Moolenaar 5 * Copyright (c) 2002 Hiten Mahesh Pandya 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #include <string.h> 33 #include <uuid.h> 34 35 /* A macro used to improve the readability of uuid_compare(). */ 36 #define DIFF_RETURN(a, b, field) do { \ 37 if ((a)->field != (b)->field) \ 38 return (((a)->field < (b)->field) ? -1 : 1); \ 39 } while (0) 40 41 /* 42 * uuid_compare() - compare two UUIDs. 43 * See also: 44 * http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm 45 * 46 * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller 47 * than any non-nil UUID. 48 */ 49 int32_t 50 uuid_compare(const uuid_t *a, const uuid_t *b, uint32_t *status) 51 { 52 int res; 53 54 if (status != NULL) 55 *status = uuid_s_ok; 56 57 /* Deal with NULL or equal pointers. */ 58 if (a == b) 59 return (0); 60 if (a == NULL) 61 return ((uuid_is_nil(b, NULL)) ? 0 : -1); 62 if (b == NULL) 63 return ((uuid_is_nil(a, NULL)) ? 0 : 1); 64 65 /* We have to compare the hard way. */ 66 DIFF_RETURN(a, b, time_low); 67 DIFF_RETURN(a, b, time_mid); 68 DIFF_RETURN(a, b, time_hi_and_version); 69 DIFF_RETURN(a, b, clock_seq_hi_and_reserved); 70 DIFF_RETURN(a, b, clock_seq_low); 71 72 res = memcmp(a->node, b->node, sizeof(a->node)); 73 if (res) 74 return ((res < 0) ? -1 : 1); 75 return (0); 76 } 77 78 #undef DIFF_RETURN 79