xref: /onnv-gate/usr/src/lib/libnisdb/yptol/shim_lockmap.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
24*0Sstevel@tonic-gate  * Use is subject to license terms.
25*0Sstevel@tonic-gate  */
26*0Sstevel@tonic-gate 
27*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate  * DESCRIPTION: Contains a front end to the map locking code. These are called
31*0Sstevel@tonic-gate  *		when a map, or its map_ctrl structure, needs to be locked
32*0Sstevel@tonic-gate  *		for a short time for internal modification. This lock should
33*0Sstevel@tonic-gate  *		not be held between DBM operations.
34*0Sstevel@tonic-gate  *
35*0Sstevel@tonic-gate  * NOTE :	This is not the same mechanism as the `update lock` which is
36*0Sstevel@tonic-gate  *		held for a relatively long period when a map is being update
37*0Sstevel@tonic-gate  *		from the DIT.
38*0Sstevel@tonic-gate  */
39*0Sstevel@tonic-gate 
40*0Sstevel@tonic-gate #include <unistd.h>
41*0Sstevel@tonic-gate #include <syslog.h>
42*0Sstevel@tonic-gate #include <sys/mman.h>
43*0Sstevel@tonic-gate #include <thread.h>
44*0Sstevel@tonic-gate #include <synch.h>
45*0Sstevel@tonic-gate #include <ndbm.h>
46*0Sstevel@tonic-gate #include "ypsym.h"
47*0Sstevel@tonic-gate #include "shim.h"
48*0Sstevel@tonic-gate 
49*0Sstevel@tonic-gate /*
50*0Sstevel@tonic-gate  * FUNCTION : 	lock_map_ctrl()
51*0Sstevel@tonic-gate  *
52*0Sstevel@tonic-gate  * DESCRIPTION: Front end to the lock routine taking map_ctrl structure as
53*0Sstevel@tonic-gate  *		argument. Saves cost of a hash operation.
54*0Sstevel@tonic-gate  *
55*0Sstevel@tonic-gate  * GIVEN :	Map_ctrl structure .
56*0Sstevel@tonic-gate  *
57*0Sstevel@tonic-gate  * RETURNS :	Same as lock core
58*0Sstevel@tonic-gate  */
59*0Sstevel@tonic-gate int
lock_map_ctrl(map_ctrl * map)60*0Sstevel@tonic-gate lock_map_ctrl(map_ctrl *map)
61*0Sstevel@tonic-gate {
62*0Sstevel@tonic-gate 	int ret;
63*0Sstevel@tonic-gate 
64*0Sstevel@tonic-gate 	ret = lock_core(map->hash_val);
65*0Sstevel@tonic-gate 
66*0Sstevel@tonic-gate 	return (ret);
67*0Sstevel@tonic-gate }
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate /*
70*0Sstevel@tonic-gate  * FUNCTION : 	unlock_map_ctrl()
71*0Sstevel@tonic-gate  *
72*0Sstevel@tonic-gate  * DESCRIPTION: Front end to the unlock routine taking map_ctrl structure as
73*0Sstevel@tonic-gate  *		argument. Saves cost of a hash operation.
74*0Sstevel@tonic-gate  *
75*0Sstevel@tonic-gate  * GIVEN :	Map_ctrl structure .
76*0Sstevel@tonic-gate  *
77*0Sstevel@tonic-gate  * RETURNS :	Same as lock core
78*0Sstevel@tonic-gate  */
79*0Sstevel@tonic-gate int
unlock_map_ctrl(map_ctrl * map)80*0Sstevel@tonic-gate unlock_map_ctrl(map_ctrl *map)
81*0Sstevel@tonic-gate {
82*0Sstevel@tonic-gate 	int ret;
83*0Sstevel@tonic-gate 
84*0Sstevel@tonic-gate 	ret = unlock_core(map->hash_val);
85*0Sstevel@tonic-gate 	return (ret);
86*0Sstevel@tonic-gate }
87