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 (c) 1998 by Sun Microsystems, Inc.
24 */
25#ifndef	_CACHE_DOT_H
26#define	_CACHE_DOT_H
27
28#pragma ident	"%Z%%M%	%I%	%E% SMI"
29
30/*
31 * ld.so directory caching
32 */
33#include	<sys/types.h>
34
35/*
36 * Shared object lookup performance in the run-time link editor is
37 * enhanced through the use of caches for directories that the editor
38 * searches.  A given "cache" describes the contents of a single directory,
39 * and each cache entry contains the canonical name for a shared object
40 * as well as its absolute pathname.
41 *
42 * Within a cache, "pointers" are really relative addresses to some absolute
43 * address (often the base address of the containing database).
44 */
45
46/*
47 * Relative pointer macros.
48 */
49#define	RELPTR(base, absptr) ((long)(absptr) - (long)(base))
50#define	AP(base) ((caddr_t)base)
51
52/*
53 * Definitions for cache structures.
54 */
55#define	DB_HASH		11		/* number of hash buckets in caches */
56#define	LD_CACHE_MAGIC 	0x041155	/* cookie to identify data structure */
57#define	LD_CACHE_VERSION 0		/* version number of cache structure */
58
59struct	dbe	{			/* element of a directory cache */
60	long	dbe_next;		/* (rp) next element on this list */
61	long	dbe_lop;		/* (rp) canonical name for object */
62	long	dbe_name;		/* (rp) absolute name */
63};
64
65struct	db	{			/* directory cache database */
66	long	db_name;		/* (rp) directory contained here */
67	struct	dbe db_hash[DB_HASH];	/* hash buckets */
68	caddr_t	db_chain;		/* private to database mapping */
69};
70
71struct dbf 	{			/* cache file image */
72	long dbf_magic;			/* identifying cookie */
73	long dbf_version;		/* version no. of these dbs */
74	long dbf_machtype;		/* machine type */
75	long dbf_db;		/* directory cache dbs */
76};
77
78/*
79 * Structures used to describe and access a database.
80 */
81struct	dbd	{			/* data base descriptor */
82	struct	dbd *dbd_next;		/* next one on this list */
83	struct	db *dbd_db;		/* data base described by this */
84};
85
86struct	dd	{			/* directory descriptor */
87	struct	dd *dd_next;		/* next one on this list */
88	struct	db *dd_db;		/* data base described by this */
89};
90
91/*
92 * Interfaces imported/exported by the lookup code.
93 */
94
95char	*ask_db();			/* ask db for highest minor number */
96struct	db *lo_cache();			/* obtain cache for directory name */
97
98#endif
99