1 /* cache.c - routines to maintain an in-core cache of entries */
3 * Copyright 1998-2000 The OpenLDAP Foundation, All Rights Reserved.
4 * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
7 * Copyright 2001 The OpenLDAP Foundation, All Rights Reserved.
8 * COPYING RESTRICTIONS APPLY, see COPYRIGHT file
10 * Copyright 2001, Pierangelo Masarati, All rights reserved. <ando@sys-net.it>
12 * This work has beed deveolped for the OpenLDAP Foundation
13 * in the hope that it may be useful to the Open Source community,
14 * but WITHOUT ANY WARRANTY.
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17 * on any computer system, and to alter it and redistribute it, subject
18 * to the following restrictions:
20 * 1. The author and SysNet s.n.c. are not responsible for the consequences
21 * of use of this software, no matter how awful, even if they arise from
24 * 2. The origin of this software must not be misrepresented, either by
25 * explicit claim or by omission. Since few users ever read sources,
26 * credits should appear in the documentation.
28 * 3. Altered versions must be plainly marked as such, and must not be
29 * misrepresented as being the original software. Since few users
30 * ever read sources, credits should appear in the documentation.
31 * SysNet s.n.c. cannot be responsible for the consequences of the
34 * 4. This notice may not be removed or altered.
43 #include "back-monitor.h"
46 * compares entries based on the dn
54 struct monitorcache *cc1 = ( struct monitorcache * )c1;
55 struct monitorcache *cc2 = ( struct monitorcache * )c2;
57 int d = cc1->mc_ndn->bv_len - cc2->mc_ndn->bv_len;
60 * case sensitive, because the dn MUST be normalized
62 return d != 0 ? d : strcmp( cc1->mc_ndn->bv_val, cc2->mc_ndn->bv_val );
66 * checks for duplicate entries
74 struct monitorcache *cc1 = ( struct monitorcache * )c1;
75 struct monitorcache *cc2 = ( struct monitorcache * )c2;
79 * case sensitive, because the dn MUST be normalized
82 int cmp = monitor_cache_cmp( c1, c2 );
84 int d = cc1->mc_ndn->bv_len - cc2->mc_ndn->bv_len;
86 d != 0 ? d : strcmp( cc1->mc_ndn->bv_val, cc2->mc_ndn->bv_val );
89 return cmp == 0 ? -1 : 0;
93 * adds an entry to the cache and inits the mutex
97 struct monitorinfo *mi,
101 struct monitorcache *mc;
102 struct monitorentrypriv *mp;
105 assert( mi != NULL );
108 mp = ( struct monitorentrypriv *)e->e_private;
109 ldap_pvt_thread_mutex_init( &mp->mp_mutex );
111 mc = ( struct monitorcache * )ch_malloc( sizeof( struct monitorcache ) );
112 mc->mc_ndn = &e->e_nname;
114 ldap_pvt_thread_mutex_lock( &mi->mi_cache_mutex );
115 rc = avl_insert( &mi->mi_cache, ( caddr_t )mc,
116 monitor_cache_cmp, monitor_cache_dup );
117 ldap_pvt_thread_mutex_unlock( &mi->mi_cache_mutex );
123 * locks the entry (no r/w)
130 struct monitorentrypriv *mp;
133 assert( e->e_private != NULL );
135 mp = ( struct monitorentrypriv * )e->e_private;
136 ldap_pvt_thread_mutex_lock( &mp->mp_mutex );
142 * gets an entry from the cache based on the normalized dn
147 struct monitorinfo *mi,
152 struct monitorcache tmp_mc, *mc;
154 assert( mi != NULL );
155 assert( ndn != NULL );
156 assert( ep != NULL );
159 ldap_pvt_thread_mutex_lock( &mi->mi_cache_mutex );
160 mc = ( struct monitorcache * )avl_find( mi->mi_cache,
161 ( caddr_t )&tmp_mc, monitor_cache_cmp );
164 /* entry is returned with mutex locked */
165 monitor_cache_lock( mc->mc_e );
166 ldap_pvt_thread_mutex_unlock( &mi->mi_cache_mutex );
172 ldap_pvt_thread_mutex_unlock( &mi->mi_cache_mutex );
179 * If the entry exists in cache, it is returned in locked status;
180 * otherwise, if the parent exists, if it may generate volatile
181 * descendants an attempt to generate the required entry is
182 * performed and, if successful, the entry is returned
185 monitor_cache_dn2entry(
186 struct monitorinfo *mi,
194 struct berval p_ndn = { 0L, NULL };
196 struct monitorentrypriv *mp;
198 assert( mi != NULL );
199 assert( ndn != NULL );
200 assert( ep != NULL );
201 assert( matched != NULL );
205 rc = monitor_cache_get( mi, ndn, ep );
206 if ( !rc && *ep != NULL ) {
210 /* try with parent/ancestors */
212 p_ndn.bv_val = dn_parent( NULL, ndn->bv_val );
215 if ( p_ndn.bv_val == NULL ) {
220 p_ndn.bv_len = ndn->bv_len
221 - ( ber_len_t ) ( p_ndn.bv_val - ndn->bv_val );
224 rc = monitor_cache_dn2entry( mi, &p_ndn, &e_parent, matched );
225 if ( rc || e_parent == NULL) {
229 mp = ( struct monitorentrypriv * )e_parent->e_private;
231 if ( mp->mp_flags & MONITOR_F_VOLATILE_CH ) {
232 /* parent entry generates volatile children */
233 rc = monitor_entry_create( mi, ndn, e_parent, ep );
237 monitor_cache_release( mi, e_parent );
246 * releases the lock of the entry; if it is marked as volatile, it is
250 monitor_cache_release(
251 struct monitorinfo *mi,
255 struct monitorentrypriv *mp;
257 assert( mi != NULL );
259 assert( e->e_private != NULL );
261 mp = ( struct monitorentrypriv * )e->e_private;
263 if ( mp->mp_flags & MONITOR_F_VOLATILE ) {
264 struct monitorcache *mc, tmp_mc;
266 /* volatile entries do not return to cache */
267 ldap_pvt_thread_mutex_lock( &mi->mi_cache_mutex );
268 tmp_mc.mc_ndn = &e->e_nname;
269 mc = avl_delete( &mi->mi_cache,
270 ( caddr_t )&tmp_mc, monitor_cache_cmp );
271 ldap_pvt_thread_mutex_unlock( &mi->mi_cache_mutex );
274 ldap_pvt_thread_mutex_destroy( &mp->mp_mutex );
282 ldap_pvt_thread_mutex_unlock( &mp->mp_mutex );