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Diffstat (limited to 'usr/src/lib/libuuid/common/uuid_misc.c')
| -rw-r--r-- | usr/src/lib/libuuid/common/uuid_misc.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/usr/src/lib/libuuid/common/uuid_misc.c b/usr/src/lib/libuuid/common/uuid_misc.c new file mode 100644 index 0000000000..7aec84fee1 --- /dev/null +++ b/usr/src/lib/libuuid/common/uuid_misc.c @@ -0,0 +1,186 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2000,2002 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +/* + * The copyright in this file is taken from the original Leach + * & Salz UUID specification, from which this implementation + * is derived. + */ + +/* + * Copyright (c) 1990- 1993, 1996 Open Software Foundation, Inc. + * Copyright (c) 1989 by Hewlett-Packard Company, Palo Alto, Ca. & + * Digital Equipment Corporation, Maynard, Mass. Copyright (c) 1998 + * Microsoft. To anyone who acknowledges that this file is provided + * "AS IS" without any express or implied warranty: permission to use, + * copy, modify, and distribute this file for any purpose is hereby + * granted without fee, provided that the above copyright notices and + * this notice appears in all source code copies, and that none of the + * names of Open Software Foundation, Inc., Hewlett-Packard Company, + * or Digital Equipment Corporation be used in advertising or + * publicity pertaining to distribution of the software without + * specific, written prior permission. Neither Open Software + * Foundation, Inc., Hewlett-Packard Company, Microsoft, nor Digital + * Equipment Corporation makes any representations about the + * suitability of this software for any purpose. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <uuid/uuid.h> +#include <stdlib.h> +#include <strings.h> +#include "uuid_misc.h" + +#define UUCMP(u1, u2) if (u1 != u2) return ((u1 < u2) ? -1 : 1) +#define UUIDS_PER_TOD_CALL 10 /* tv_usec is multiplied by 10 */ + +void struct_to_string(uuid_t, struct uuid *); +void string_to_struct(struct uuid *, uuid_t); +void get_system_time(uuid_time_t *); + +/* + * Name: _get_current_time + * + * Description: get-current_time -- get time as 60 bit 100ns ticks + * since the beginning of unix time. + * Compensate for the fact that real clock resolution is + * less than 100ns. + * + * Returns: None. + * + */ +void +_get_current_time(uuid_time_t *timestamp) +{ + uuid_time_t time_now; + static uuid_time_t time_last = 0; + static uint16_t uuids_this_tick = 0; + int done; + + done = 0; + while (!done) { + get_system_time(&time_now); + + /* + * if clock reading changed since last UUID generated... + */ + if (time_last != time_now) { + /* + * reset count of uuids generated with + * this clock reading + */ + uuids_this_tick = 0; + done = 1; + } else { + uuids_this_tick++; + if (uuids_this_tick < UUIDS_PER_TOD_CALL) + done = 1; + } + /* + * too many UUIDs for this gettimeofday call; spin + */ + } + time_last = time_now; + /* + * add the count of uuids to low order bits of the clock reading + */ + *timestamp = time_now + uuids_this_tick; +} + +/* + * Name: _get_random + * + * Description: Gets a random number. + * + * Returns: nbytes of random information. + * + */ +uint16_t +_get_random(void) +{ + static int initted = 0; + uuid_time_t time_now; + long seed; + + if (!initted) { + get_system_time(&time_now); + time_now = time_now/UUIDS_PER_TOD_CALL; + seed = (unsigned)(((time_now >> 32) ^ time_now)&0xffffffff); + srand48(seed); + initted = 1; + } + return (mrand48()); +} + +/* + * Name: uuid_compare + * + * Description: Compares 2 uuid strings + * + * Returns: -1 if u1 < u2, 1 if u1 > u2 and 0 if both are equal + */ +int +uuid_compare(uuid_t uu1, uuid_t uu2) +{ + + struct uuid uuid1, uuid2; + + string_to_struct(&uuid1, uu1); + string_to_struct(&uuid2, uu2); + UUCMP(uuid1.time_low, uuid2.time_low); + UUCMP(uuid1.time_mid, uuid2.time_mid); + UUCMP(uuid1.time_hi_and_version, uuid2.time_hi_and_version); + UUCMP(uuid1.clock_seq_hi_and_reserved, uuid2.clock_seq_hi_and_reserved); + UUCMP(uuid1.clock_seq_low, uuid2.clock_seq_low); + return (memcmp(uuid1.node_addr, uuid2.node_addr, 6)); +} + +/* + * Name: get_system_time + * + * Description: system dependent call to get the current system time. + * Returned as 100ns ticks since Oct 15, 1582, but + * resolution may be less than 100ns. + * + * Returns: None + */ +void +get_system_time(uuid_time_t *uuid_time) +{ + struct timeval tp; + + (void) gettimeofday(&tp, (struct timezone *)0); + + /* + * Offset between UUID formatted times and Unix formatted times. + * UUID UTC base time is October 15, 1582. + * Unix base time is January 1, 1970. + */ + *uuid_time = (uint64_t)tp.tv_sec * 10000000; + *uuid_time += tp.tv_usec * 10; + *uuid_time += 0x01B21DD213814000; +} |