cache.h revision 96702 
1/*-
2 * Copyright (c) 1992 Keith Muller.
3 * Copyright (c) 1992, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Keith Muller of the University of California, San Diego.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 *      @(#)cache.h	8.1 (Berkeley) 5/31/93
38 * $FreeBSD: head/bin/pax/cache.h 96702 2002-05-16 01:57:20Z trhodes $
39 */
40
41/*
42 * Constants and data structures used to implement group and password file
43 * caches. Traditional passwd/group cache routines perform quite poorly with
44 * archives. The chances of hitting a valid lookup with an archive is quite a
45 * bit worse than with files already resident on the filesystem. These misses
46 * create a MAJOR performance cost. To address this problem, these routines
47 * cache both hits and misses.
48 *
49 * NOTE:  name lengths must be as large as those stored in ANY PROTOCOL and
50 * as stored in the passwd and group files. CACHE SIZES MUST BE PRIME
51 */
52#define UNMLEN		32	/* >= user name found in any protocol */
53#define GNMLEN		32	/* >= group name found in any protocol */
54#define UID_SZ		317	/* size of user_name/uid cache */
55#define UNM_SZ		317	/* size of user_name/uid cache */
56#define GID_SZ		251	/* size of gid cache */
57#define GNM_SZ		317	/* size of group name cache */
58#define VALID		1	/* entry and name are valid */
59#define INVALID		2	/* entry valid, name NOT valid */
60
61/*
62 * Node structures used in the user, group, uid, and gid caches.
63 */
64
65typedef struct uidc {
66	int valid;		/* is this a valid or a miss entry */
67	char name[UNMLEN];	/* uid name */
68	uid_t uid;		/* cached uid */
69} UIDC;
70
71typedef struct gidc {
72	int valid;		/* is this a valid or a miss entry */
73	char name[GNMLEN];	/* gid name */
74	gid_t gid;		/* cached gid */
75} GIDC;
76