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 2003 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29#include <sys/systm.h>
30#include <sys/param.h>
31#include <sys/atomic.h>
32#include <sys/kmem.h>
33#include <sys/refstr.h>
34#include <sys/refstr_impl.h>
35
36refstr_t *
37refstr_alloc(const char *str)
38{
39	refstr_t *rsp;
40	size_t size = sizeof (rsp->rs_size) + sizeof (rsp->rs_refcnt) +
41		strlen(str) + 1;
42
43	ASSERT(size <= UINT32_MAX);
44	rsp = kmem_alloc(size, KM_SLEEP);
45	rsp->rs_size = (uint32_t)size;
46	rsp->rs_refcnt = 1;
47	(void) strcpy(rsp->rs_string, str);
48	return (rsp);
49}
50
51const char *
52refstr_value(refstr_t *rsp)
53{
54	return (rsp != NULL ? (const char *)rsp->rs_string : NULL);
55}
56
57void
58refstr_hold(refstr_t *rsp)
59{
60	atomic_add_32(&rsp->rs_refcnt, 1);
61}
62
63void
64refstr_rele(refstr_t *rsp)
65{
66	if (atomic_add_32_nv(&rsp->rs_refcnt, -1) == 0)
67		kmem_free(rsp, (size_t)rsp->rs_size);
68}
69