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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 #ifndef _SYS_UNIQUE_H 27 #define _SYS_UNIQUE_H 28 29 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #include <sys/zfs_context.h> 32 33 #ifdef __cplusplus 34 extern "C" { 35 #endif 36 37 /* The number of significant bits in each unique value. */ 38 #define UNIQUE_BITS 56 39 40 void unique_init(void); 41 void unique_fini(void); 42 43 /* 44 * Return a new unique value (which will not be uniquified against until 45 * it is unique_insert()-ed. 46 */ 47 uint64_t unique_create(void); 48 49 /* Return a unique value, which equals the one passed in if possible. */ 50 uint64_t unique_insert(uint64_t value); 51 52 /* Indicate that this value no longer needs to be uniquified against. */ 53 void unique_remove(uint64_t value); 54 55 #ifdef __cplusplus 56 } 57 #endif 58 59 #endif /* _SYS_UNIQUE_H */ 60