1 /*- 2 * Copyright (c) 2002,2005 Marcel Moolenaar 3 * Copyright (c) 2002 Hiten Mahesh Pandya 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 #include <string.h> 31 #include <uuid.h> 32 33 /* 34 * uuid_compare() - compare two UUIDs. 35 * See also: 36 * http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm 37 * 38 * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller 39 * than any non-nil UUID. 40 */ 41 int32_t 42 uuid_compare(const uuid_t *a, const uuid_t *b, uint32_t *status) 43 { 44 int res; 45 int64_t res64; 46 47 if (status != NULL) 48 *status = uuid_s_ok; 49 50 /* Deal with NULL or equal pointers. */ 51 if (a == b) 52 return (0); 53 if (a == NULL) 54 return ((uuid_is_nil(b, NULL)) ? 0 : -1); 55 if (b == NULL) 56 return ((uuid_is_nil(a, NULL)) ? 0 : 1); 57 58 /* 59 * We have to compare the hard way. 60 * 61 * Note that time_low is defined as unsigned 32-bit 62 * integer, therefore, with a significantly large 63 * a->time_low and a small b->time_low, we will end 64 * up with a value which is larger than 0x7fffffff 65 * which is negative if casted to signed 32-bit 66 * integer. 67 */ 68 res64 = (int64_t)a->time_low - (int64_t)b->time_low; 69 if (res64) 70 return ((res64 < 0) ? -1 : 1); 71 res = (int)a->time_mid - (int)b->time_mid; 72 if (res) 73 return ((res < 0) ? -1 : 1); 74 res = (int)a->time_hi_and_version - (int)b->time_hi_and_version; 75 if (res) 76 return ((res < 0) ? -1 : 1); 77 res = (int)a->clock_seq_hi_and_reserved - 78 (int)b->clock_seq_hi_and_reserved; 79 if (res) 80 return ((res < 0) ? -1 : 1); 81 res = (int)a->clock_seq_low - (int)b->clock_seq_low; 82 if (res) 83 return ((res < 0) ? -1 : 1); 84 res = memcmp(a->node, b->node, sizeof(a->node)); 85 if (res) 86 return ((res < 0) ? -1 : 1); 87 return (0); 88 } 89