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: src/lib/libc/uuid/uuid_compare.c,v 1.6 2007/04/05 02:07:33 delphij Exp $ 28 * $DragonFly: src/lib/libc/uuid/uuid_compare.c,v 1.1 2007/06/16 19:57:14 dillon Exp $ 29 */ 30 31 #include <string.h> 32 #include <uuid.h> 33 34 /* A macro used to improve the readability of uuid_compare(). */ 35 #define DIFF_RETURN(a, b, field) do { \ 36 if ((a)->field != (b)->field) \ 37 return (((a)->field < (b)->field) ? -1 : 1); \ 38 } while (0) 39 40 /* 41 * uuid_compare() - compare two UUIDs. 42 * See also: 43 * http://www.opengroup.org/onlinepubs/009629399/uuid_compare.htm 44 * 45 * NOTE: Either UUID can be NULL, meaning a nil UUID. nil UUIDs are smaller 46 * than any non-nil UUID. 47 */ 48 int32_t 49 uuid_compare(const uuid_t *a, const uuid_t *b, uint32_t *status) 50 { 51 int res; 52 53 if (status != NULL) 54 *status = uuid_s_ok; 55 56 /* Deal with NULL or equal pointers. */ 57 if (a == b) 58 return (0); 59 if (a == NULL) 60 return ((uuid_is_nil(b, NULL)) ? 0 : -1); 61 if (b == NULL) 62 return ((uuid_is_nil(a, NULL)) ? 0 : 1); 63 64 /* We have to compare the hard way. */ 65 DIFF_RETURN(a, b, time_low); 66 DIFF_RETURN(a, b, time_mid); 67 DIFF_RETURN(a, b, time_hi_and_version); 68 DIFF_RETURN(a, b, clock_seq_hi_and_reserved); 69 DIFF_RETURN(a, b, clock_seq_low); 70 71 res = memcmp(a->node, b->node, sizeof(a->node)); 72 if (res) 73 return ((res < 0) ? -1 : 1); 74 return (0); 75 } 76 77 #undef DIFF_RETURN 78