/* $OpenLDAP: pkg/ldap/servers/slapd/back-meta/dncache.c,v 1.10.2.7 2007/01/02 21:44:04 kurt Exp $ */
/* This work is part of OpenLDAP Software .
*
* Copyright 1999-2007 The OpenLDAP Foundation.
* Portions Copyright 2001-2003 Pierangelo Masarati.
* Portions Copyright 1999-2003 Howard Chu.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in the file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* .
*/
/* ACKNOWLEDGEMENTS:
* This work was initially developed by the Howard Chu for inclusion
* in OpenLDAP Software and subsequently enhanced by Pierangelo
* Masarati.
*/
#include "portable.h"
#include
#include
#include "slap.h"
#include "../back-ldap/back-ldap.h"
#include "back-meta.h"
/*
* The dncache, at present, maps an entry to the target that holds it.
*/
typedef struct metadncacheentry_t {
struct berval dn;
int target;
time_t lastupdated;
} metadncacheentry_t;
/*
* meta_dncache_cmp
*
* compares two struct metadncacheentry; used by avl stuff
* FIXME: modify avl stuff to delete an entry based on cmp
* (e.g. when ttl expired?)
*/
int
meta_dncache_cmp(
const void *c1,
const void *c2 )
{
metadncacheentry_t *cc1 = ( metadncacheentry_t * )c1;
metadncacheentry_t *cc2 = ( metadncacheentry_t * )c2;
/*
* case sensitive, because the dn MUST be normalized
*/
return ber_bvcmp( &cc1->dn, &cc2->dn);
}
/*
* meta_dncache_dup
*
* returns -1 in case a duplicate struct metadncacheentry has been inserted;
* used by avl stuff
*/
int
meta_dncache_dup(
void *c1,
void *c2 )
{
metadncacheentry_t *cc1 = ( metadncacheentry_t * )c1;
metadncacheentry_t *cc2 = ( metadncacheentry_t * )c2;
/*
* case sensitive, because the dn MUST be normalized
*/
return ( ber_bvcmp( &cc1->dn, &cc2->dn ) == 0 ) ? -1 : 0;
}
/*
* meta_dncache_get_target
*
* returns the target a dn belongs to, or -1 in case the dn is not
* in the cache
*/
int
meta_dncache_get_target(
metadncache_t *cache,
struct berval *ndn )
{
metadncacheentry_t tmp_entry,
*entry;
int target = META_TARGET_NONE;
assert( cache != NULL );
assert( ndn != NULL );
tmp_entry.dn = *ndn;
ldap_pvt_thread_mutex_lock( &cache->mutex );
entry = ( metadncacheentry_t * )avl_find( cache->tree,
( caddr_t )&tmp_entry, meta_dncache_cmp );
if ( entry != NULL ) {
/*
* if cache->ttl < 0, cache never expires;
* if cache->ttl = 0 no cache is used; shouldn't get here
* else, cache is used with ttl
*/
if ( cache->ttl < 0 ) {
target = entry->target;
} else {
if ( entry->lastupdated+cache->ttl > slap_get_time() ) {
target = entry->target;
}
}
}
ldap_pvt_thread_mutex_unlock( &cache->mutex );
return target;
}
/*
* meta_dncache_update_entry
*
* updates target and lastupdated of a struct metadncacheentry if exists,
* otherwise it gets created; returns -1 in case of error
*/
int
meta_dncache_update_entry(
metadncache_t *cache,
struct berval *ndn,
int target )
{
metadncacheentry_t *entry,
tmp_entry;
time_t curr_time = 0L;
int err = 0;
assert( cache != NULL );
assert( ndn != NULL );
/*
* if cache->ttl < 0, cache never expires;
* if cache->ttl = 0 no cache is used; shouldn't get here
* else, cache is used with ttl
*/
if ( cache->ttl > 0 ) {
curr_time = slap_get_time();
}
tmp_entry.dn = *ndn;
ldap_pvt_thread_mutex_lock( &cache->mutex );
entry = ( metadncacheentry_t * )avl_find( cache->tree,
( caddr_t )&tmp_entry, meta_dncache_cmp );
if ( entry != NULL ) {
entry->target = target;
entry->lastupdated = curr_time;
} else {
entry = ch_malloc( sizeof( metadncacheentry_t ) + ndn->bv_len + 1 );
if ( entry == NULL ) {
err = -1;
goto error_return;
}
entry->dn.bv_len = ndn->bv_len;
entry->dn.bv_val = (char *)&entry[ 1 ];
AC_MEMCPY( entry->dn.bv_val, ndn->bv_val, ndn->bv_len );
entry->dn.bv_val[ ndn->bv_len ] = '\0';
entry->target = target;
entry->lastupdated = curr_time;
err = avl_insert( &cache->tree, ( caddr_t )entry,
meta_dncache_cmp, meta_dncache_dup );
}
error_return:;
ldap_pvt_thread_mutex_unlock( &cache->mutex );
return err;
}
/*
* meta_dncache_update_entry
*
* updates target and lastupdated of a struct metadncacheentry if exists,
* otherwise it gets created; returns -1 in case of error
*/
int
meta_dncache_delete_entry(
metadncache_t *cache,
struct berval *ndn )
{
metadncacheentry_t *entry,
tmp_entry;
assert( cache != NULL );
assert( ndn != NULL );
tmp_entry.dn = *ndn;
ldap_pvt_thread_mutex_lock( &cache->mutex );
entry = avl_delete( &cache->tree, ( caddr_t )&tmp_entry,
meta_dncache_cmp );
ldap_pvt_thread_mutex_unlock( &cache->mutex );
if ( entry != NULL ) {
meta_dncache_free( ( void * )entry );
}
return 0;
}
/*
* meta_dncache_free
*
* frees an entry
*
*/
void
meta_dncache_free(
void *e )
{
free( e );
}