1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2000,2002 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* 28 * The copyright in this file is taken from the original Leach 29 * & Salz UUID specification, from which this implementation 30 * is derived. 31 */ 32 33 /* 34 * Copyright (c) 1990- 1993, 1996 Open Software Foundation, Inc. 35 * Copyright (c) 1989 by Hewlett-Packard Company, Palo Alto, Ca. & 36 * Digital Equipment Corporation, Maynard, Mass. Copyright (c) 1998 37 * Microsoft. To anyone who acknowledges that this file is provided 38 * "AS IS" without any express or implied warranty: permission to use, 39 * copy, modify, and distribute this file for any purpose is hereby 40 * granted without fee, provided that the above copyright notices and 41 * this notice appears in all source code copies, and that none of the 42 * names of Open Software Foundation, Inc., Hewlett-Packard Company, 43 * or Digital Equipment Corporation be used in advertising or 44 * publicity pertaining to distribution of the software without 45 * specific, written prior permission. Neither Open Software 46 * Foundation, Inc., Hewlett-Packard Company, Microsoft, nor Digital 47 * Equipment Corporation makes any representations about the 48 * suitability of this software for any purpose. 49 */ 50 51 #pragma ident "%Z%%M% %I% %E% SMI" 52 53 #include <uuid/uuid.h> 54 #include <stdlib.h> 55 #include <strings.h> 56 #include "uuid_misc.h" 57 58 #define UUCMP(u1, u2) if (u1 != u2) return ((u1 < u2) ? -1 : 1) 59 #define UUIDS_PER_TOD_CALL 10 /* tv_usec is multiplied by 10 */ 60 61 void struct_to_string(uuid_t, struct uuid *); 62 void string_to_struct(struct uuid *, uuid_t); 63 void get_system_time(uuid_time_t *); 64 65 /* 66 * Name: _get_current_time 67 * 68 * Description: get-current_time -- get time as 60 bit 100ns ticks 69 * since the beginning of unix time. 70 * Compensate for the fact that real clock resolution is 71 * less than 100ns. 72 * 73 * Returns: None. 74 * 75 */ 76 void 77 _get_current_time(uuid_time_t *timestamp) 78 { 79 uuid_time_t time_now; 80 static uuid_time_t time_last = 0; 81 static uint16_t uuids_this_tick = 0; 82 int done; 83 84 done = 0; 85 while (!done) { 86 get_system_time(&time_now); 87 88 /* 89 * if clock reading changed since last UUID generated... 90 */ 91 if (time_last != time_now) { 92 /* 93 * reset count of uuids generated with 94 * this clock reading 95 */ 96 uuids_this_tick = 0; 97 done = 1; 98 } else { 99 uuids_this_tick++; 100 if (uuids_this_tick < UUIDS_PER_TOD_CALL) 101 done = 1; 102 } 103 /* 104 * too many UUIDs for this gettimeofday call; spin 105 */ 106 } 107 time_last = time_now; 108 /* 109 * add the count of uuids to low order bits of the clock reading 110 */ 111 *timestamp = time_now + uuids_this_tick; 112 } 113 114 /* 115 * Name: _get_random 116 * 117 * Description: Gets a random number. 118 * 119 * Returns: nbytes of random information. 120 * 121 */ 122 uint16_t 123 _get_random(void) 124 { 125 static int initted = 0; 126 uuid_time_t time_now; 127 long seed; 128 129 if (!initted) { 130 get_system_time(&time_now); 131 time_now = time_now/UUIDS_PER_TOD_CALL; 132 seed = (unsigned)(((time_now >> 32) ^ time_now)&0xffffffff); 133 srand48(seed); 134 initted = 1; 135 } 136 return (mrand48()); 137 } 138 139 /* 140 * Name: uuid_compare 141 * 142 * Description: Compares 2 uuid strings 143 * 144 * Returns: -1 if u1 < u2, 1 if u1 > u2 and 0 if both are equal 145 */ 146 int 147 uuid_compare(uuid_t uu1, uuid_t uu2) 148 { 149 150 struct uuid uuid1, uuid2; 151 152 string_to_struct(&uuid1, uu1); 153 string_to_struct(&uuid2, uu2); 154 UUCMP(uuid1.time_low, uuid2.time_low); 155 UUCMP(uuid1.time_mid, uuid2.time_mid); 156 UUCMP(uuid1.time_hi_and_version, uuid2.time_hi_and_version); 157 UUCMP(uuid1.clock_seq_hi_and_reserved, uuid2.clock_seq_hi_and_reserved); 158 UUCMP(uuid1.clock_seq_low, uuid2.clock_seq_low); 159 return (memcmp(uuid1.node_addr, uuid2.node_addr, 6)); 160 } 161 162 /* 163 * Name: get_system_time 164 * 165 * Description: system dependent call to get the current system time. 166 * Returned as 100ns ticks since Oct 15, 1582, but 167 * resolution may be less than 100ns. 168 * 169 * Returns: None 170 */ 171 void 172 get_system_time(uuid_time_t *uuid_time) 173 { 174 struct timeval tp; 175 176 (void) gettimeofday(&tp, (struct timezone *)0); 177 178 /* 179 * Offset between UUID formatted times and Unix formatted times. 180 * UUID UTC base time is October 15, 1582. 181 * Unix base time is January 1, 1970. 182 */ 183 *uuid_time = (uint64_t)tp.tv_sec * 10000000; 184 *uuid_time += tp.tv_usec * 10; 185 *uuid_time += 0x01B21DD213814000; 186 } 187