Adding upstream version 2.5.13+dfsg.upstream/2.5.13+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2573 insertions, 0 deletions

diff --git a/servers/slapd/back-monitor/init.c b/servers/slapd/back-monitor/init.c
new file mode 100644
index 0000000..43749dd
--- /dev/null
+++ b/servers/slapd/back-monitor/init.c
@@ -0,0 +1,2573 @@
+/* init.c - initialize monitor backend */
+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2001-2022 The OpenLDAP Foundation.
+ * Portions Copyright 2001-2003 Pierangelo Masarati.
+ * 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 file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+/* ACKNOWLEDGEMENTS:
+ * This work was initially developed by Pierangelo Masarati for inclusion
+ * in OpenLDAP Software.
+ */
+
+#include "portable.h"
+
+#include <stdio.h>
+#include <ac/string.h>
+
+#include <lutil.h>
+#include "slap.h"
+#include "slap-config.h"
+#include "lber_pvt.h"
+#include "back-monitor.h"
+
+#include "slap-config.h"
+
+#undef INTEGRATE_CORE_SCHEMA
+
+/*
+ * used by many functions to add description to entries
+ *
+ * WARNING: be_monitor may change as new databases are added,
+ * so it should not be used outside monitor_back_db_init()
+ * until monitor_back_db_open is called.
+ */
+BackendDB			*be_monitor;
+
+static struct monitor_subsys_t	**monitor_subsys;
+static int			monitor_subsys_opened;
+static monitor_info_t		monitor_info;
+static const monitor_extra_t monitor_extra = {
+	monitor_back_is_configured,
+	monitor_back_get_subsys,
+	monitor_back_get_subsys_by_dn,
+
+	monitor_back_register_subsys,
+	monitor_back_register_backend,
+	monitor_back_register_database,
+	monitor_back_register_overlay_info,
+	monitor_back_register_overlay,
+	monitor_back_register_entry,
+	monitor_back_register_entry_parent,
+	monitor_back_register_entry_attrs,
+	monitor_back_register_entry_callback,
+
+	monitor_back_unregister_entry,
+	monitor_back_unregister_entry_parent,
+	monitor_back_unregister_entry_attrs,
+	monitor_back_unregister_entry_callback,
+
+	monitor_back_entry_stub,
+	monitor_back_entrypriv_create,
+	monitor_back_register_subsys_late,
+	monitor_back_entry_get_unlocked
+};
+	
+
+/*
+ * subsystem data
+ *
+ * the known subsystems are added to the subsystems
+ * array at backend initialization; other subsystems
+ * may be added by calling monitor_back_register_subsys()
+ * before the database is opened (e.g. by other backends
+ * or by overlays or modules).
+ */
+static struct monitor_subsys_t known_monitor_subsys[] = {
+	{ 
+		SLAPD_MONITOR_BACKEND_NAME, 
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about available backends." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_backend_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_CONN_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about connections." ),
+			BER_BVNULL },
+		MONITOR_F_VOLATILE_CH,
+		monitor_subsys_conn_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_DATABASE_NAME, 	
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about configured databases." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_database_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_LISTENER_NAME, 	
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about active listeners." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_listener_init,
+		NULL,	/* destroy */
+		NULL,	/* update */
+		NULL,	/* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_LOG_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about logging." ),
+		  	BER_BVC( "Set the attribute \"managedInfo\" to the desired log levels." ),
+			BER_BVNULL },
+		MONITOR_F_NONE,
+		monitor_subsys_log_init,
+		NULL,	/* destroy */
+		NULL,	/* update */
+		NULL,   /* create */
+		NULL,	/* modify */
+       	}, { 
+		SLAPD_MONITOR_OPS_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about performed operations." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_ops_init,
+		NULL,	/* destroy */
+		NULL,	/* update */
+		NULL,   /* create */
+		NULL,	/* modify */
+       	}, { 
+		SLAPD_MONITOR_OVERLAY_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about available overlays." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_overlay_init,
+		NULL,	/* destroy */
+		NULL,	/* update */
+		NULL,   /* create */
+		NULL,	/* modify */
+	}, { 
+		SLAPD_MONITOR_SASL_NAME, 	
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about SASL." ),
+			BER_BVNULL },
+		MONITOR_F_NONE,
+		NULL,   /* init */
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_SENT_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains statistics." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_sent_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL,	/* modify */
+       	}, { 
+		SLAPD_MONITOR_THREAD_NAME, 	
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about threads." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_thread_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_TIME_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about time." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_time_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL,	/* modify */
+       	}, { 
+		SLAPD_MONITOR_TLS_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about TLS." ),
+			BER_BVNULL },
+		MONITOR_F_NONE,
+		NULL,   /* init */
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL,   /* create */
+		NULL	/* modify */
+       	}, { 
+		SLAPD_MONITOR_RWW_NAME,
+		BER_BVNULL, BER_BVNULL, BER_BVNULL,
+		{ BER_BVC( "This subsystem contains information about read/write waiters." ),
+			BER_BVNULL },
+		MONITOR_F_PERSISTENT_CH,
+		monitor_subsys_rww_init,
+		NULL,	/* destroy */
+		NULL,   /* update */
+		NULL, 	/* create */
+		NULL	/* modify */
+       	}, { NULL }
+};
+
+int
+monitor_subsys_is_opened( void )
+{
+	return monitor_subsys_opened;
+}
+
+int
+monitor_back_register_subsys(
+	monitor_subsys_t	*ms )
+{
+	int	i = 0;
+
+	if ( monitor_subsys ) {
+		for ( ; monitor_subsys[ i ] != NULL; i++ )
+			/* just count'em */ ;
+	}
+
+	monitor_subsys = ch_realloc( monitor_subsys,
+			( 2 + i ) * sizeof( monitor_subsys_t * ) );
+
+	if ( monitor_subsys == NULL ) {
+		return -1;
+	}
+
+	monitor_subsys[ i ] = ms;
+	monitor_subsys[ i + 1 ] = NULL;
+
+	/* if a subsystem is registered __AFTER__ subsystem 
+	 * initialization (depending on the sequence the databases
+	 * are listed in slapd.conf), init it */
+	if ( monitor_subsys_is_opened() ) {
+
+		/* FIXME: this should only be possible
+		 * if be_monitor is already initialized */
+		assert( be_monitor != NULL );
+
+		if ( ms->mss_open && ( *ms->mss_open )( be_monitor, ms ) ) {
+			return -1;
+		}
+
+		ms->mss_flags |= MONITOR_F_OPENED;
+	}
+
+	return 0;
+}
+
+enum {
+	LIMBO_ENTRY,
+	LIMBO_ENTRY_PARENT,
+	LIMBO_ATTRS,
+	LIMBO_CB,
+	LIMBO_BACKEND,
+	LIMBO_DATABASE,
+	LIMBO_OVERLAY_INFO,
+	LIMBO_OVERLAY,
+	LIMBO_SUBSYS,
+
+	LIMBO_LAST
+};
+
+typedef struct entry_limbo_t {
+	int			el_type;
+	BackendInfo		*el_bi;
+	BackendDB		*el_be;
+	slap_overinst		*el_on;
+	Entry			*el_e;
+	Attribute		*el_a;
+	struct berval		*el_ndn;
+	struct berval		el_nbase;
+	int			el_scope;
+	struct berval		el_filter;
+	monitor_callback_t	*el_cb;
+	monitor_subsys_t	*el_mss;
+	unsigned long		el_flags;
+	struct entry_limbo_t	*el_next;
+} entry_limbo_t;
+
+int
+monitor_back_is_configured( void )
+{
+	return be_monitor != NULL;
+}
+
+int
+monitor_back_register_subsys_late(
+	monitor_subsys_t	*ms )
+{
+	entry_limbo_t	**elpp, el = { 0 };
+	monitor_info_t 	*mi;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_subsys_late: "
+			"monitor database not configured.\n" );
+		return -1;
+	}
+
+	/* everything is ready, can register already */
+	if ( monitor_subsys_is_opened() ) {
+		return monitor_back_register_subsys( ms );
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+
+	el.el_type = LIMBO_SUBSYS;
+
+	el.el_mss = ms;
+
+	for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		/* go to last */;
+
+	*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+
+	el.el_next = NULL;
+	**elpp = el;
+
+	return 0;
+}
+
+int
+monitor_back_register_backend(
+	BackendInfo		*bi )
+{
+	return -1;
+}
+
+int
+monitor_back_register_overlay_info(
+	slap_overinst		*on )
+{
+	return -1;
+}
+
+int
+monitor_back_register_backend_limbo(
+	BackendInfo		*bi )
+{
+	return -1;
+}
+
+int
+monitor_back_register_database_limbo(
+	BackendDB		*be,
+	struct berval		*ndn_out )
+{
+	entry_limbo_t	**elpp, el = { 0 };
+	monitor_info_t 	*mi;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_database_limbo: "
+			"monitor database not configured.\n" );
+		return -1;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+
+	el.el_type = LIMBO_DATABASE;
+
+	el.el_be = be->bd_self;
+	el.el_ndn = ndn_out;
+	
+	for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		/* go to last */;
+
+	*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+
+	el.el_next = NULL;
+	**elpp = el;
+
+	return 0;
+}
+
+int
+monitor_back_register_overlay_info_limbo(
+	slap_overinst		*on )
+{
+	return -1;
+}
+
+int
+monitor_back_register_overlay_limbo(
+	BackendDB		*be,
+	struct slap_overinst	*on,
+	struct berval		*ndn_out )
+{
+	entry_limbo_t	**elpp, el = { 0 };
+	monitor_info_t 	*mi;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_overlay_limbo: "
+			"monitor database not configured.\n" );
+		return -1;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+
+	el.el_type = LIMBO_OVERLAY;
+
+	el.el_be = be->bd_self;
+	el.el_on = on;
+	el.el_ndn = ndn_out;
+	
+	for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		/* go to last */;
+
+	*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+
+	el.el_next = NULL;
+	**elpp = el;
+
+	return 0;
+}
+
+int
+monitor_back_register_entry(
+	Entry			*e,
+	monitor_callback_t	*cb,
+	monitor_subsys_t	*mss,
+	unsigned long		flags )
+{
+	monitor_info_t 	*mi;
+	int rc = 0;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_entry(\"%s\"): "
+			"monitor database not configured.\n",
+			e->e_name.bv_val );
+		return -1;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+	assert( e != NULL );
+	assert( e->e_private == NULL );
+	
+	if ( monitor_subsys_is_opened() ) {
+		Entry		*e_parent = NULL,
+				*e_new = NULL,
+				**ep = NULL;
+		struct berval	pdn = BER_BVNULL;
+		monitor_entry_t *mp = NULL,
+				*mp_parent = NULL;
+
+		if ( monitor_cache_get( mi, &e->e_nname, &e_parent ) == 0 ) {
+			/* entry exists */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"entry exists\n",
+				e->e_name.bv_val );
+			monitor_cache_release( mi, e_parent );
+			return -1;
+		}
+
+		dnParent( &e->e_nname, &pdn );
+		if ( monitor_cache_get( mi, &pdn, &e_parent ) != 0 ) {
+			/* parent does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"parent \"%s\" not found\n",
+				e->e_name.bv_val, pdn.bv_val );
+			return -1;
+		}
+
+		assert( e_parent->e_private != NULL );
+		mp_parent = ( monitor_entry_t * )e_parent->e_private;
+
+		if ( mp_parent->mp_flags & MONITOR_F_VOLATILE ) {
+			/* entry is volatile; cannot append children */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"parent \"%s\" is volatile\n",
+				e->e_name.bv_val, e_parent->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		mp = monitor_entrypriv_create();
+		if ( mp == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"monitor_entrypriv_create() failed\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		e_new = entry_dup( e );
+		if ( e_new == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"entry_dup() failed\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+		
+		e_new->e_private = ( void * )mp;
+		if ( mss != NULL ) {
+			mp->mp_info = mss;
+			mp->mp_flags = flags;
+
+		} else {
+			mp->mp_info = mp_parent->mp_info;
+			mp->mp_flags = mp_parent->mp_flags | MONITOR_F_SUB;
+		}
+		mp->mp_cb = cb;
+
+		ep = &mp_parent->mp_children;
+		for ( ; *ep; ) {
+			mp_parent = ( monitor_entry_t * )(*ep)->e_private;
+			ep = &mp_parent->mp_next;
+		}
+		*ep = e_new;
+
+		if ( monitor_cache_add( mi, e_new ) ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"unable to add entry\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+done:;
+		if ( rc ) {
+			if ( mp ) {
+				ch_free( mp );
+			}
+			if ( e_new ) {
+				e_new->e_private = NULL;
+				entry_free( e_new );
+			}
+		}
+
+		if ( e_parent ) {
+			monitor_cache_release( mi, e_parent );
+		}
+
+	} else {
+		entry_limbo_t	**elpp, el = { 0 };
+
+		el.el_type = LIMBO_ENTRY;
+
+		el.el_e = entry_dup( e );
+		if ( el.el_e == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"entry_dup() failed\n",
+				e->e_name.bv_val );
+			return -1;
+		}
+		
+		el.el_cb = cb;
+		el.el_mss = mss;
+		el.el_flags = flags;
+
+		for ( elpp = &mi->mi_entry_limbo;
+				*elpp;
+				elpp = &(*elpp)->el_next )
+			/* go to last */;
+
+		*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+		if ( *elpp == NULL ) {
+			el.el_e->e_private = NULL;
+			entry_free( el.el_e );
+			return -1;
+		}
+
+		el.el_next = NULL;
+		**elpp = el;
+	}
+
+	return rc;
+}
+
+int
+monitor_back_register_entry_parent(
+	Entry			*e,
+	monitor_callback_t	*cb,
+	monitor_subsys_t	*mss,
+	unsigned long		flags,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	monitor_info_t 	*mi;
+	struct berval	ndn = BER_BVNULL;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_entry_parent(base=\"%s\" scope=%s filter=\"%s\"): "
+			"monitor database not configured.\n",
+			BER_BVISNULL( nbase ) ? "" : nbase->bv_val,
+			ldap_pvt_scope2str( scope ),
+			BER_BVISNULL( filter ) ? "" : filter->bv_val );
+		return -1;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+	assert( e != NULL );
+	assert( e->e_private == NULL );
+
+	if ( BER_BVISNULL( filter ) ) {
+		/* need a filter */
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_entry_parent(\"\"): "
+			"need a valid filter\n" );
+		return -1;
+	}
+
+	if ( monitor_subsys_is_opened() ) {
+		Entry		*e_parent = NULL,
+				*e_new = NULL,
+				**ep = NULL;
+		struct berval	e_name = BER_BVNULL,
+				e_nname = BER_BVNULL;
+		monitor_entry_t *mp = NULL,
+				*mp_parent = NULL;
+		int		rc = 0;
+
+		if ( monitor_search2ndn( nbase, scope, filter, &ndn ) ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_parent(\"\"): "
+				"base=\"%s\" scope=%s filter=\"%s\": "
+				"unable to find entry\n",
+				nbase->bv_val ? nbase->bv_val : "\"\"",
+				ldap_pvt_scope2str( scope ),
+				filter->bv_val );
+			return -1;
+		}
+
+		if ( monitor_cache_get( mi, &ndn, &e_parent ) != 0 ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_parent(\"%s\"): "
+				"parent entry does not exist\n",
+				ndn.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		assert( e_parent->e_private != NULL );
+		mp_parent = ( monitor_entry_t * )e_parent->e_private;
+
+		if ( mp_parent->mp_flags & MONITOR_F_VOLATILE ) {
+			/* entry is volatile; cannot append callback */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_parent(\"%s\"): "
+				"entry is volatile\n",
+				e_parent->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		build_new_dn( &e_name, &e_parent->e_name, &e->e_name, NULL );
+		build_new_dn( &e_nname, &e_parent->e_nname, &e->e_nname, NULL );
+
+		if ( monitor_cache_get( mi, &e_nname, &e_new ) == 0 ) {
+			/* entry already exists */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_parent(\"%s\"): "
+				"entry already exists\n",
+				e_name.bv_val );
+			monitor_cache_release( mi, e_new );
+			e_new = NULL;
+			rc = -1;
+			goto done;
+		}
+
+		mp = monitor_entrypriv_create();
+		if ( mp == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_parent(\"%s\"): "
+				"monitor_entrypriv_create() failed\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		e_new = entry_dup( e );
+		if ( e_new == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"entry_dup() failed\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+		ch_free( e_new->e_name.bv_val );
+		ch_free( e_new->e_nname.bv_val );
+		e_new->e_name = e_name;
+		e_new->e_nname = e_nname;
+		
+		e_new->e_private = ( void * )mp;
+		if ( mss != NULL ) {
+			mp->mp_info = mss;
+			mp->mp_flags = flags;
+
+		} else {
+			mp->mp_info = mp_parent->mp_info;
+			mp->mp_flags = mp_parent->mp_flags | MONITOR_F_SUB;
+		}
+		mp->mp_cb = cb;
+
+		ep = &mp_parent->mp_children;
+		for ( ; *ep; ) {
+			mp_parent = ( monitor_entry_t * )(*ep)->e_private;
+			ep = &mp_parent->mp_next;
+		}
+		*ep = e_new;
+
+		if ( monitor_cache_add( mi, e_new ) ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"unable to add entry\n",
+				e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+done:;
+		if ( !BER_BVISNULL( &ndn ) ) {
+			ch_free( ndn.bv_val );
+		}
+
+		if ( rc ) {
+			if ( mp ) {
+				ch_free( mp );
+			}
+			if ( e_new ) {
+				e_new->e_private = NULL;
+				entry_free( e_new );
+			}
+		}
+
+		if ( e_parent ) {
+			monitor_cache_release( mi, e_parent );
+		}
+
+	} else {
+		entry_limbo_t	**elpp = NULL, el = { 0 };
+
+		el.el_type = LIMBO_ENTRY_PARENT;
+
+		el.el_e = entry_dup( e );
+		if ( el.el_e == NULL ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry(\"%s\"): "
+				"entry_dup() failed\n",
+				e->e_name.bv_val );
+			goto done_limbo;
+		}
+		
+		if ( !BER_BVISNULL( nbase ) ) {
+			ber_dupbv( &el.el_nbase, nbase );
+		}
+
+		el.el_scope = scope;
+		if ( !BER_BVISNULL( filter ) ) {
+			ber_dupbv( &el.el_filter, filter  );
+		}
+
+		el.el_cb = cb;
+		el.el_mss = mss;
+		el.el_flags = flags;
+
+		for ( elpp = &mi->mi_entry_limbo;
+				*elpp;
+				elpp = &(*elpp)->el_next )
+			/* go to last */;
+
+		*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+		if ( *elpp == NULL ) {
+			goto done_limbo;
+		}
+
+done_limbo:;
+		if ( *elpp != NULL ) {
+			el.el_next = NULL;
+			**elpp = el;
+
+		} else {
+			if ( !BER_BVISNULL( &el.el_filter ) ) {
+				ch_free( el.el_filter.bv_val );
+			}
+			if ( !BER_BVISNULL( &el.el_nbase ) ) {
+				ch_free( el.el_nbase.bv_val );
+			}
+			entry_free( el.el_e );
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+static int
+monitor_search2ndn_cb( Operation *op, SlapReply *rs )
+{
+	if ( rs->sr_type == REP_SEARCH ) {
+		struct berval	*ndn = op->o_callback->sc_private;
+
+		if ( !BER_BVISNULL( ndn ) ) {
+			rs->sr_err = LDAP_SIZELIMIT_EXCEEDED;
+			ch_free( ndn->bv_val );
+			BER_BVZERO( ndn );
+			return rs->sr_err;
+		}
+		
+		ber_dupbv( ndn, &rs->sr_entry->e_nname );
+	}
+
+	return 0;
+}
+
+int
+monitor_search2ndn(
+	struct berval	*nbase,
+	int		scope,
+	struct berval	*filter,
+	struct berval	*ndn )
+{
+	Connection	conn = { 0 };
+	OperationBuffer	opbuf;
+	Operation	*op;
+	void	*thrctx;
+	SlapReply	rs = { REP_RESULT };
+	slap_callback	cb = { NULL, monitor_search2ndn_cb, NULL, NULL };
+	int		rc;
+
+	BER_BVZERO( ndn );
+
+	if ( be_monitor == NULL ) {
+		return -1;
+	}
+
+	thrctx = ldap_pvt_thread_pool_context();
+	connection_fake_init2( &conn, &opbuf, thrctx, 0 );
+	op = &opbuf.ob_op;
+
+	op->o_tag = LDAP_REQ_SEARCH;
+
+	/* use global malloc for now */
+	if ( op->o_tmpmemctx ) {
+		op->o_tmpmemctx = NULL;
+	}
+	op->o_tmpmfuncs = &ch_mfuncs;
+
+	op->o_bd = be_monitor;
+	if ( nbase == NULL || BER_BVISNULL( nbase ) ) {
+		ber_dupbv_x( &op->o_req_dn, &op->o_bd->be_suffix[ 0 ],
+				op->o_tmpmemctx );
+		ber_dupbv_x( &op->o_req_ndn, &op->o_bd->be_nsuffix[ 0 ],
+				op->o_tmpmemctx );
+
+	} else {
+		if ( dnPrettyNormal( NULL, nbase, &op->o_req_dn, &op->o_req_ndn,
+					op->o_tmpmemctx ) ) {
+			return -1;
+		}
+	}
+
+	op->o_callback = &cb;
+	cb.sc_private = (void *)ndn;
+
+	op->ors_scope = scope;
+	op->ors_filter = str2filter_x( op, filter->bv_val );
+	if ( op->ors_filter == NULL ) {
+		rc = LDAP_OTHER;
+		goto cleanup;
+	}
+	ber_dupbv_x( &op->ors_filterstr, filter, op->o_tmpmemctx );
+	op->ors_attrs = slap_anlist_no_attrs;
+	op->ors_attrsonly = 0;
+	op->ors_tlimit = SLAP_NO_LIMIT;
+	op->ors_slimit = 1;
+	op->ors_limit = NULL;
+	op->ors_deref = LDAP_DEREF_NEVER;
+
+	op->o_nocaching = 1;
+	op->o_managedsait = SLAP_CONTROL_NONCRITICAL;
+
+	op->o_dn = be_monitor->be_rootdn;
+	op->o_ndn = be_monitor->be_rootndn;
+
+	rc = op->o_bd->be_search( op, &rs );
+
+cleanup:;
+	if ( op->ors_filter != NULL ) {
+		filter_free_x( op, op->ors_filter, 1 );
+	}
+	if ( !BER_BVISNULL( &op->ors_filterstr ) ) {
+		op->o_tmpfree( op->ors_filterstr.bv_val, op->o_tmpmemctx );
+	}
+	if ( !BER_BVISNULL( &op->o_req_dn ) ) {
+		op->o_tmpfree( op->o_req_dn.bv_val, op->o_tmpmemctx );
+	}
+	if ( !BER_BVISNULL( &op->o_req_ndn ) ) {
+		op->o_tmpfree( op->o_req_ndn.bv_val, op->o_tmpmemctx );
+	}
+
+	if ( rc != 0 ) {
+		return rc;
+	}
+
+	switch ( rs.sr_err ) {
+	case LDAP_SUCCESS:
+		if ( BER_BVISNULL( ndn ) ) {
+			rc = -1;
+		}
+		break;
+			
+	case LDAP_SIZELIMIT_EXCEEDED:
+	default:
+		if ( !BER_BVISNULL( ndn ) ) {
+			ber_memfree( ndn->bv_val );
+			BER_BVZERO( ndn );
+		}
+		rc = -1;
+		break;
+	}
+
+	return rc;
+}
+
+int
+monitor_back_register_entry_attrs(
+	struct berval		*ndn_in,
+	Attribute		*a,
+	monitor_callback_t	*cb,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	monitor_info_t 	*mi;
+	struct berval	ndn = BER_BVNULL;
+	char		*fname = ( a == NULL ? "callback" : "attrs" );
+	struct berval	empty_bv = BER_BVC("");
+
+	if ( nbase == NULL ) nbase = &empty_bv;
+	if ( filter == NULL ) filter = &empty_bv;
+
+	if ( be_monitor == NULL ) {
+		Debug(LDAP_DEBUG_ANY,
+		      "monitor_back_register_entry_%s(base=\"%s\" scope=%s filter=\"%s\"): " "monitor database not configured.\n\n",
+		      fname, BER_BVISNULL(nbase) ? "" : nbase->bv_val,
+		      ldap_pvt_scope2str(scope),
+		      BER_BVISNULL(filter) ? "" : filter->bv_val );
+
+		return -1;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+
+	if ( ndn_in != NULL ) {
+		ndn = *ndn_in;
+	}
+
+	if ( a == NULL && cb == NULL ) {
+		/* nothing to do */
+		return -1;
+	}
+
+	if ( ( ndn_in == NULL || BER_BVISNULL( &ndn ) )
+			&& BER_BVISNULL( filter ) )
+	{
+		/* need a filter */
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_register_entry_%s(\"\"): "
+			"need a valid filter\n",
+			fname );
+		return -1;
+	}
+
+	if ( monitor_subsys_is_opened() ) {
+		Entry			*e = NULL;
+		Attribute		**atp = NULL;
+		monitor_entry_t 	*mp = NULL;
+		monitor_callback_t	**mcp = NULL;
+		int			rc = 0;
+		int			freeit = 0;
+
+		if ( BER_BVISNULL( &ndn ) ) {
+			if ( monitor_search2ndn( nbase, scope, filter, &ndn ) ) {
+				Debug(LDAP_DEBUG_ANY,
+				      "monitor_back_register_entry_%s(\"\"): " "base=\"%s\" scope=%s filter=\"%s\": " "unable to find entry\n\n",
+				      fname,
+				      nbase->bv_val ? nbase->bv_val : "\"\"",
+				      ldap_pvt_scope2str(scope),
+				      filter->bv_val );
+				return -1;
+			}
+
+			freeit = 1;
+		}
+
+		if ( monitor_cache_get( mi, &ndn, &e ) != 0 ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_%s(\"%s\"): "
+				"entry does not exist\n",
+				fname, ndn.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		assert( e->e_private != NULL );
+		mp = ( monitor_entry_t * )e->e_private;
+
+		if ( mp->mp_flags & MONITOR_F_VOLATILE ) {
+			/* entry is volatile; cannot append callback */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_register_entry_%s(\"%s\"): "
+				"entry is volatile\n",
+				fname, e->e_name.bv_val );
+			rc = -1;
+			goto done;
+		}
+
+		if ( a ) {
+			for ( atp = &e->e_attrs; *atp; atp = &(*atp)->a_next )
+				/* just get to last */ ;
+
+			for ( ; a != NULL; a = a->a_next ) {
+				assert( a->a_desc != NULL );
+				assert( a->a_vals != NULL );
+
+				if ( attr_find( e->e_attrs, a->a_desc ) ) {
+					attr_merge( e, a->a_desc, a->a_vals,
+						a->a_nvals == a->a_vals ? NULL : a->a_nvals );
+
+				} else {
+					*atp = attr_dup( a );
+					if ( *atp == NULL ) {
+						Debug( LDAP_DEBUG_ANY,
+							"monitor_back_register_entry_%s(\"%s\"): "
+							"attr_dup() failed\n",
+							fname, e->e_name.bv_val );
+						rc = -1;
+						goto done;
+					}
+					atp = &(*atp)->a_next;
+				}
+			}
+		}
+
+		if ( cb ) {
+			for ( mcp = &mp->mp_cb; *mcp; mcp = &(*mcp)->mc_next )
+				/* go to tail */ ;
+		
+			/* NOTE: we do not clear cb->mc_next, so this function
+			 * can be used to append a list of callbacks */
+			(*mcp) = cb;
+		}
+
+done:;
+		if ( rc ) {
+			if ( atp && *atp ) {
+				attrs_free( *atp );
+				*atp = NULL;
+			}
+		}
+
+		if ( freeit ) {
+			ber_memfree( ndn.bv_val );
+		}
+
+		if ( e ) {
+			monitor_cache_release( mi, e );
+		}
+
+	} else {
+		entry_limbo_t	**elpp, el = { 0 };
+
+		el.el_type = LIMBO_ATTRS;
+		el.el_ndn = ndn_in;
+		if ( !BER_BVISNULL( nbase ) ) {
+			ber_dupbv( &el.el_nbase, nbase);
+		}
+		el.el_scope = scope;
+		if ( !BER_BVISNULL( filter ) ) {
+			ber_dupbv( &el.el_filter, filter  );
+		}
+
+		el.el_a = attrs_dup( a );
+		el.el_cb = cb;
+
+		for ( elpp = &mi->mi_entry_limbo;
+				*elpp;
+				elpp = &(*elpp)->el_next )
+			/* go to last */;
+
+		*elpp = (entry_limbo_t *)ch_malloc( sizeof( entry_limbo_t ) );
+		if ( *elpp == NULL ) {
+			if ( !BER_BVISNULL( &el.el_filter ) ) {
+				ch_free( el.el_filter.bv_val );
+			}
+			if ( el.el_a != NULL ) {
+				attrs_free( el.el_a );
+			}
+			if ( !BER_BVISNULL( &el.el_nbase ) ) {
+				ch_free( &el.el_nbase.bv_val );
+			}
+			return -1;
+		}
+
+		el.el_next = NULL;
+		**elpp = el;
+	}
+
+	return 0;
+}
+
+int
+monitor_back_register_entry_callback(
+	struct berval		*ndn,
+	monitor_callback_t	*cb,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	return monitor_back_register_entry_attrs( ndn, NULL, cb,
+			nbase, scope, filter );
+}
+
+/*
+ * TODO: add corresponding calls to remove installed callbacks, entries
+ * and so, in case the entity that installed them is removed (e.g. a 
+ * database, via back-config)
+ */
+int
+monitor_back_unregister_entry(
+	struct berval	*ndn )
+{
+	monitor_info_t 	*mi;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_unregister_entry(\"%s\"): "
+			"monitor database not configured.\n",
+			ndn->bv_val );
+
+		return -1;
+	}
+
+	/* entry will be regularly freed, and resources released
+	 * according to callbacks */
+	if ( slapd_shutdown ) {
+		return 0;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+
+	if ( monitor_subsys_is_opened() ) {
+		Entry			*e = NULL;
+		monitor_entry_t 	*mp = NULL;
+		monitor_callback_t	*cb = NULL;
+
+		if ( monitor_cache_remove( mi, ndn, &e ) != 0 ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_unregister_entry(\"%s\"): "
+				"entry removal failed.\n",
+				ndn->bv_val );
+			return -1;
+		}
+
+		mp = (monitor_entry_t *)e->e_private;
+		assert( mp != NULL );
+
+		for ( cb = mp->mp_cb; cb != NULL; ) {
+			monitor_callback_t	*next = cb->mc_next;
+
+			if ( cb->mc_free ) {
+				(void)cb->mc_free( e, &cb->mc_private );
+			}
+			ch_free( cb );
+
+			cb = next;
+		}
+
+		ch_free( mp );
+		e->e_private = NULL;
+		entry_free( e );
+
+	} else {
+		entry_limbo_t	**elpp;
+
+		for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		{
+			entry_limbo_t	*elp = *elpp;
+
+			if ( elp->el_type == LIMBO_ENTRY
+				&& dn_match( ndn, &elp->el_e->e_nname ) )
+			{
+				monitor_callback_t	*cb, *next;
+
+				for ( cb = elp->el_cb; cb; cb = next ) {
+					/* FIXME: call callbacks? */
+					next = cb->mc_next;
+					if ( cb->mc_dispose ) {
+						cb->mc_dispose( &cb->mc_private );
+					}
+					ch_free( cb );
+				}
+				assert( elp->el_e != NULL );
+				elp->el_e->e_private = NULL;
+				entry_free( elp->el_e );
+				*elpp = elp->el_next;
+				ch_free( elp );
+				elpp = NULL;
+				break;
+			}
+		}
+
+		if ( elpp != NULL ) {
+			/* not found!  where did it go? */
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int
+monitor_back_unregister_entry_parent(
+	struct berval		*nrdn,
+	monitor_callback_t	*target_cb,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	monitor_info_t 	*mi;
+	struct berval	ndn = BER_BVNULL;
+
+	if ( be_monitor == NULL ) {
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_unregister_entry_parent(base=\"%s\" scope=%s filter=\"%s\"): "
+			"monitor database not configured.\n",
+			BER_BVISNULL( nbase ) ? "" : nbase->bv_val,
+			ldap_pvt_scope2str( scope ),
+			BER_BVISNULL( filter ) ? "" : filter->bv_val );
+
+		return -1;
+	}
+
+	/* entry will be regularly freed, and resources released
+	 * according to callbacks */
+	if ( slapd_shutdown ) {
+		return 0;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+
+	if ( ( nrdn == NULL || BER_BVISNULL( nrdn ) )
+			&& BER_BVISNULL( filter ) )
+	{
+		/* need a filter */
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_unregister_entry_parent(\"\"): "
+			"need a valid filter\n" );
+		return -1;
+	}
+
+	if ( monitor_subsys_is_opened() ) {
+		Entry			*e = NULL;
+		monitor_entry_t 	*mp = NULL;
+
+		if ( monitor_search2ndn( nbase, scope, filter, &ndn ) ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_unregister_entry_parent(\"\"): "
+				"base=\"%s\" scope=%s filter=\"%s\": "
+				"unable to find entry\n",
+				nbase->bv_val ? nbase->bv_val : "\"\"",
+				ldap_pvt_scope2str( scope ),
+				filter->bv_val );
+			return -1;
+		}
+
+		if ( monitor_cache_remove( mi, &ndn, &e ) != 0 ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_unregister_entry(\"%s\"): "
+				"entry removal failed.\n",
+				ndn.bv_val );
+			ber_memfree( ndn.bv_val );
+			return -1;
+		}
+		ber_memfree( ndn.bv_val );
+
+		mp = (monitor_entry_t *)e->e_private;
+		assert( mp != NULL );
+
+		if ( target_cb != NULL ) {
+			monitor_callback_t	**cbp;
+
+			for ( cbp = &mp->mp_cb; *cbp != NULL; cbp = &(*cbp)->mc_next ) {
+				if ( *cbp == target_cb ) {
+					if ( (*cbp)->mc_free ) {
+						(void)(*cbp)->mc_free( e, &(*cbp)->mc_private );
+					}
+					*cbp = (*cbp)->mc_next;
+					ch_free( target_cb );
+					break;
+				}
+			}
+		}
+
+
+		ch_free( mp );
+		e->e_private = NULL;
+		entry_free( e );
+
+	} else {
+		entry_limbo_t	**elpp;
+
+		for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		{
+			entry_limbo_t	*elp = *elpp;
+
+			if ( elp->el_type == LIMBO_ENTRY_PARENT
+				&& dn_match( nrdn, &elp->el_e->e_nname )
+				&& dn_match( nbase, &elp->el_nbase )
+				&& scope == elp->el_scope
+				&& bvmatch( filter, &elp->el_filter ) )
+			{
+				monitor_callback_t	*cb, *next;
+
+				for ( cb = elp->el_cb; cb; cb = next ) {
+					/* FIXME: call callbacks? */
+					next = cb->mc_next;
+					if ( cb->mc_dispose ) {
+						cb->mc_dispose( &cb->mc_private );
+					}
+					ch_free( cb );
+				}
+				assert( elp->el_e != NULL );
+				elp->el_e->e_private = NULL;
+				entry_free( elp->el_e );
+				if ( !BER_BVISNULL( &elp->el_nbase ) ) {
+					ch_free( elp->el_nbase.bv_val );
+				}
+				if ( !BER_BVISNULL( &elp->el_filter ) ) {
+					ch_free( elp->el_filter.bv_val );
+				}
+				*elpp = elp->el_next;
+				ch_free( elp );
+				elpp = NULL;
+				break;
+			}
+		}
+
+		if ( elpp != NULL ) {
+			/* not found!  where did it go? */
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int
+monitor_back_unregister_entry_attrs(
+	struct berval		*ndn_in,
+	Attribute		*target_a,
+	monitor_callback_t	*target_cb,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	monitor_info_t 	*mi;
+	struct berval	ndn = BER_BVNULL;
+	char		*fname = ( target_a == NULL ? "callback" : "attrs" );
+
+	if ( be_monitor == NULL ) {
+		Debug(LDAP_DEBUG_ANY,
+		      "monitor_back_unregister_entry_%s(base=\"%s\" scope=%s filter=\"%s\"): " "monitor database not configured.\n\n",
+		      fname, BER_BVISNULL(nbase) ? "" : nbase->bv_val,
+		      ldap_pvt_scope2str(scope),
+		      BER_BVISNULL(filter) ? "" : filter->bv_val );
+
+		return -1;
+	}
+
+	/* entry will be regularly freed, and resources released
+	 * according to callbacks */
+	if ( slapd_shutdown ) {
+		return 0;
+	}
+
+	mi = ( monitor_info_t * )be_monitor->be_private;
+
+	assert( mi != NULL );
+
+	if ( ndn_in != NULL ) {
+		ndn = *ndn_in;
+	}
+
+	if ( target_a == NULL && target_cb == NULL ) {
+		/* nothing to do */
+		return -1;
+	}
+
+	if ( ( ndn_in == NULL || BER_BVISNULL( &ndn ) )
+			&& BER_BVISNULL( filter ) )
+	{
+		/* need a filter */
+		Debug( LDAP_DEBUG_ANY,
+			"monitor_back_unregister_entry_%s(\"\"): "
+			"need a valid filter\n",
+			fname );
+		return -1;
+	}
+
+	if ( monitor_subsys_is_opened() ) {
+		Entry			*e = NULL;
+		monitor_entry_t 	*mp = NULL;
+		int			freeit = 0;
+
+		if ( BER_BVISNULL( &ndn ) ) {
+			if ( monitor_search2ndn( nbase, scope, filter, &ndn ) ) {
+				Debug(LDAP_DEBUG_ANY,
+				      "monitor_back_unregister_entry_%s(\"\"): " "base=\"%s\" scope=%d filter=\"%s\": " "unable to find entry\n\n",
+				      fname,
+				      nbase->bv_val ? nbase->bv_val : "\"\"",
+				      scope, filter->bv_val );
+				return -1;
+			}
+
+			freeit = 1;
+		}
+
+		if ( monitor_cache_get( mi, &ndn, &e ) != 0 ) {
+			/* entry does not exist */
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_unregister_entry(\"%s\"): "
+				"entry removal failed.\n",
+				ndn.bv_val );
+			return -1;
+		}
+
+		mp = (monitor_entry_t *)e->e_private;
+		assert( mp != NULL );
+
+		if ( target_cb != NULL ) {
+			monitor_callback_t	**cbp;
+
+			for ( cbp = &mp->mp_cb; *cbp != NULL; cbp = &(*cbp)->mc_next ) {
+				if ( *cbp == target_cb ) {
+					if ( (*cbp)->mc_free ) {
+						(void)(*cbp)->mc_free( e, &(*cbp)->mc_private );
+					}
+					*cbp = (*cbp)->mc_next;
+					ch_free( target_cb );
+					break;
+				}
+			}
+		}
+
+		if ( target_a != NULL ) {
+			Attribute	*a;
+
+			for ( a = target_a; a != NULL; a = a->a_next ) {
+				Modification	mod = { 0 };
+				const char	*text;
+				char		textbuf[ SLAP_TEXT_BUFLEN ];
+
+				mod.sm_op = LDAP_MOD_DELETE;
+				mod.sm_desc = a->a_desc;
+				mod.sm_values = a->a_vals;
+				mod.sm_nvalues = a->a_nvals;
+
+				(void)modify_delete_values( e, &mod, 1,
+					&text, textbuf, sizeof( textbuf ) );
+			}
+		}
+
+		if ( freeit ) {
+			ber_memfree( ndn.bv_val );
+		}
+
+		monitor_cache_release( mi, e );
+
+	} else {
+		entry_limbo_t	**elpp;
+
+		for ( elpp = &mi->mi_entry_limbo;
+			*elpp;
+			elpp = &(*elpp)->el_next )
+		{
+			entry_limbo_t	*elp = *elpp;
+
+			if ( elp->el_type == LIMBO_ATTRS
+				&& dn_match( nbase, &elp->el_nbase )
+				&& scope == elp->el_scope
+				&& bvmatch( filter, &elp->el_filter ) )
+			{
+				monitor_callback_t	*cb, *next;
+
+				for ( cb = elp->el_cb; cb; cb = next ) {
+					/* FIXME: call callbacks? */
+					next = cb->mc_next;
+					if ( cb->mc_dispose ) {
+						cb->mc_dispose( &cb->mc_private );
+					}
+					ch_free( cb );
+				}
+				assert( elp->el_e == NULL );
+				if ( elp->el_a != NULL ) {
+					attrs_free( elp->el_a );
+				}
+				if ( !BER_BVISNULL( &elp->el_nbase ) ) {
+					ch_free( elp->el_nbase.bv_val );
+				}
+				if ( !BER_BVISNULL( &elp->el_filter ) ) {
+					ch_free( elp->el_filter.bv_val );
+				}
+				*elpp = elp->el_next;
+				ch_free( elp );
+				elpp = NULL;
+				break;
+			}
+		}
+
+		if ( elpp != NULL ) {
+			/* not found!  where did it go? */
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int
+monitor_back_unregister_entry_callback(
+	struct berval		*ndn,
+	monitor_callback_t	*cb,
+	struct berval		*nbase,
+	int			scope,
+	struct berval		*filter )
+{
+	/* TODO: lookup entry (by ndn, if not NULL, and/or by callback);
+	 * unregister the callback; if a is not null, unregister the
+	 * given attrs.  In any case, call cb->cb_free */
+	return monitor_back_unregister_entry_attrs( ndn,
+		NULL, cb, nbase, scope, filter );
+}
+
+monitor_subsys_t *
+monitor_back_get_subsys( const char *name )
+{
+	if ( monitor_subsys != NULL ) {
+		int	i;
+		
+		for ( i = 0; monitor_subsys[ i ] != NULL; i++ ) {
+			if ( strcasecmp( monitor_subsys[ i ]->mss_name, name ) == 0 ) {
+				return monitor_subsys[ i ];
+			}
+		}
+	}
+
+	return NULL;
+}
+
+monitor_subsys_t *
+monitor_back_get_subsys_by_dn(
+	struct berval	*ndn,
+	int		sub )
+{
+	if ( monitor_subsys != NULL ) {
+		int	i;
+
+		if ( sub ) {
+			for ( i = 0; monitor_subsys[ i ] != NULL; i++ ) {
+				if ( dnIsSuffix( ndn, &monitor_subsys[ i ]->mss_ndn ) ) {
+					return monitor_subsys[ i ];
+				}
+			}
+
+		} else {
+			for ( i = 0; monitor_subsys[ i ] != NULL; i++ ) {
+				if ( dn_match( ndn, &monitor_subsys[ i ]->mss_ndn ) ) {
+					return monitor_subsys[ i ];
+				}
+			}
+		}
+	}
+
+	return NULL;
+}
+
+int
+monitor_back_initialize(
+	BackendInfo	*bi )
+{
+	static char		*controls[] = {
+		LDAP_CONTROL_MANAGEDSAIT,
+		NULL
+	};
+
+	static ConfigTable monitorcfg[] = {
+		{ NULL, NULL, 0, 0, 0, ARG_IGNORED,
+			NULL, NULL, NULL, NULL }
+	};
+
+	static ConfigOCs monitorocs[] = {
+		{ "( OLcfgDbOc:4.1 "
+			"NAME 'olcMonitorConfig' "
+			"DESC 'Monitor backend configuration' "
+			"SUP olcDatabaseConfig "
+			")",
+			 	Cft_Database, monitorcfg },
+		{ NULL, 0, NULL }
+	};
+
+	struct m_s {
+		char	*schema;
+		slap_mask_t flags;
+		int	offset;
+	} moc[] = {
+		{ "( 1.3.6.1.4.1.4203.666.3.16.1 "
+			"NAME 'monitor' "
+			"DESC 'OpenLDAP system monitoring' "
+			"SUP top STRUCTURAL "
+			"MUST cn "
+			"MAY ( "
+				"description "
+				"$ seeAlso "
+				"$ labeledURI "
+				"$ monitoredInfo "
+				"$ managedInfo "
+				"$ monitorOverlay "
+			") )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitor) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.2 "
+			"NAME 'monitorServer' "
+			"DESC 'Server monitoring root entry' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitorServer) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.3 "
+			"NAME 'monitorContainer' "
+			"DESC 'monitor container class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitorContainer) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.4 "
+			"NAME 'monitorCounterObject' "
+			"DESC 'monitor counter class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitorCounterObject) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.5 "
+			"NAME 'monitorOperation' "
+			"DESC 'monitor operation class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitorOperation) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.6 "
+			"NAME 'monitorConnection' "
+			"DESC 'monitor connection class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitorConnection) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.7 "
+			"NAME 'managedObject' "
+			"DESC 'monitor managed entity class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_managedObject) },
+		{ "( 1.3.6.1.4.1.4203.666.3.16.8 "
+			"NAME 'monitoredObject' "
+			"DESC 'monitor monitored entity class' "
+			"SUP monitor STRUCTURAL )", SLAP_OC_OPERATIONAL|SLAP_OC_HIDE,
+			offsetof(monitor_info_t, mi_oc_monitoredObject) },
+		{ NULL, 0, -1 }
+	}, mat[] = {
+		{ "( 1.3.6.1.4.1.4203.666.1.55.1 "
+			"NAME 'monitoredInfo' "
+			"DESC 'monitored info' "
+			/* "SUP name " */
+			"EQUALITY caseIgnoreMatch "
+			"SUBSTR caseIgnoreSubstringsMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.15{32768} "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitoredInfo) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.2 "
+			"NAME 'managedInfo' "
+			"DESC 'monitor managed info' "
+			"SUP name )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_managedInfo) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.3 "
+			"NAME 'monitorCounter' "
+			"DESC 'monitor counter' "
+			"EQUALITY integerMatch "
+			"ORDERING integerOrderingMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.27 "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorCounter) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.4 "
+			"NAME 'monitorOpCompleted' "
+			"DESC 'monitor completed operations' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorOpCompleted) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.5 "
+			"NAME 'monitorOpInitiated' "
+			"DESC 'monitor initiated operations' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorOpInitiated) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.6 "
+			"NAME 'monitorConnectionNumber' "
+			"DESC 'monitor connection number' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionNumber) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.7 "
+			"NAME 'monitorConnectionAuthzDN' "
+			"DESC 'monitor connection authorization DN' "
+			/* "SUP distinguishedName " */
+			"EQUALITY distinguishedNameMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionAuthzDN) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.8 "
+			"NAME 'monitorConnectionLocalAddress' "
+			"DESC 'monitor connection local address' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionLocalAddress) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.9 "
+			"NAME 'monitorConnectionPeerAddress' "
+			"DESC 'monitor connection peer address' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionPeerAddress) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.10 "
+			"NAME 'monitorTimestamp' "
+			"DESC 'monitor timestamp' "
+			"EQUALITY generalizedTimeMatch "
+			"ORDERING generalizedTimeOrderingMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.24 "
+			"SINGLE-VALUE "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorTimestamp) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.11 "
+			"NAME 'monitorOverlay' "
+			"DESC 'name of overlays defined for a given database' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorOverlay) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.12 "
+			"NAME 'readOnly' "
+			"DESC 'read/write status of a given database' "
+			"EQUALITY booleanMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.7 "
+			"SINGLE-VALUE "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_readOnly) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.13 "
+			"NAME 'restrictedOperation' "
+			"DESC 'name of restricted operation for a given database' "
+			"SUP managedInfo )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_restrictedOperation ) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.14 "
+			"NAME 'monitorConnectionProtocol' "
+			"DESC 'monitor connection protocol' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionProtocol) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.15 "
+			"NAME 'monitorConnectionOpsReceived' "
+			"DESC 'monitor number of operations received by the connection' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionOpsReceived) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.16 "
+			"NAME 'monitorConnectionOpsExecuting' "
+			"DESC 'monitor number of operations in execution within the connection' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionOpsExecuting) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.17 "
+			"NAME 'monitorConnectionOpsPending' "
+			"DESC 'monitor number of pending operations within the connection' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionOpsPending) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.18 "
+			"NAME 'monitorConnectionOpsCompleted' "
+			"DESC 'monitor number of operations completed within the connection' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionOpsCompleted) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.19 "
+			"NAME 'monitorConnectionGet' "
+			"DESC 'number of times connection_get() was called so far' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionGet) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.20 "
+			"NAME 'monitorConnectionRead' "
+			"DESC 'number of times connection_read() was called so far' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionRead) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.21 "
+			"NAME 'monitorConnectionWrite' "
+			"DESC 'number of times connection_write() was called so far' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionWrite) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.22 "
+			"NAME 'monitorConnectionMask' "
+			"DESC 'monitor connection mask' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionMask) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.23 "
+			"NAME 'monitorConnectionListener' "
+			"DESC 'monitor connection listener' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionListener) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.24 "
+			"NAME 'monitorConnectionPeerDomain' "
+			"DESC 'monitor connection peer domain' "
+			"SUP monitoredInfo "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionPeerDomain) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.25 "
+			"NAME 'monitorConnectionStartTime' "
+			"DESC 'monitor connection start time' "
+			"SUP monitorTimestamp "
+			"SINGLE-VALUE "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionStartTime) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.26 "
+			"NAME 'monitorConnectionActivityTime' "
+			"DESC 'monitor connection activity time' "
+			"SUP monitorTimestamp "
+			"SINGLE-VALUE "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionActivityTime) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.27 "
+			"NAME 'monitorIsShadow' "
+			"DESC 'TRUE if the database is shadow' "
+			"EQUALITY booleanMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.7 "
+			"SINGLE-VALUE "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorIsShadow) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.28 "
+			"NAME 'monitorUpdateRef' "
+			"DESC 'update referral for shadow databases' "
+			"SUP monitoredInfo "
+			"SINGLE-VALUE "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorUpdateRef) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.29 "
+			"NAME 'monitorRuntimeConfig' "
+			"DESC 'TRUE if component allows runtime configuration' "
+			"EQUALITY booleanMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.7 "
+			"SINGLE-VALUE "
+			"USAGE dSAOperation )", SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorRuntimeConfig) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.30 "
+			"NAME 'monitorSuperiorDN' "
+			"DESC 'monitor superior DN' "
+			/* "SUP distinguishedName " */
+			"EQUALITY distinguishedNameMatch "
+			"SYNTAX 1.3.6.1.4.1.1466.115.121.1.12 "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorSuperiorDN) },
+		{ "( 1.3.6.1.4.1.4203.666.1.55.31 "
+			"NAME 'monitorConnectionOpsAsync' "
+			"DESC 'monitor number of asynchronous operations in execution within the connection' "
+			"SUP monitorCounter "
+			"NO-USER-MODIFICATION "
+			"USAGE dSAOperation )", SLAP_AT_FINAL|SLAP_AT_HIDE,
+			offsetof(monitor_info_t, mi_ad_monitorConnectionOpsAsync) },
+		{ NULL, 0, -1 }
+	};
+
+	static struct {
+		char			*name;
+		char			*oid;
+	}		s_oid[] = {
+		{ "olmAttributes",			"1.3.6.1.4.1.4203.666.1.55" },
+		{ "olmSubSystemAttributes",		"olmAttributes:0" },
+		{ "olmGenericAttributes",		"olmSubSystemAttributes:0" },
+		{ "olmDatabaseAttributes",		"olmSubSystemAttributes:1" },
+		{ "olmOverlayAttributes",		"olmSubSystemAttributes:2" },
+		{ "olmModuleAttributes",		"olmSubSystemAttributes:3" },
+
+		/* for example, back-mdb specific attrs
+		 * are in "olmDatabaseAttributes:12"
+		 *
+		 * NOTE: developers, please record here OID assignments
+		 * for other modules */
+
+		{ "olmObjectClasses",			"1.3.6.1.4.1.4203.666.3.16" },
+		{ "olmSubSystemObjectClasses",		"olmObjectClasses:0" },
+		{ "olmGenericObjectClasses",		"olmSubSystemObjectClasses:0" },
+		{ "olmDatabaseObjectClasses",		"olmSubSystemObjectClasses:1" },
+		{ "olmOverlayObjectClasses",		"olmSubSystemObjectClasses:2" },
+		{ "olmModuleObjectClasses",			"olmSubSystemObjectClasses:3" },
+
+		/* for example, back-mdb specific objectClasses
+		 * are in "olmDatabaseObjectClasses:12"
+		 *
+		 * NOTE: developers, please record here OID assignments
+		 * for other modules */
+
+		{ NULL }
+	};
+
+	int			i, rc;
+	monitor_info_t		*mi = &monitor_info;
+	ConfigArgs c;
+	char	*argv[ 3 ];
+
+	argv[ 0 ] = "monitor";
+	c.argv = argv;
+	c.argc = 3;
+	c.fname = argv[0];
+
+	for ( i = 0; s_oid[ i ].name; i++ ) {
+		argv[ 1 ] = s_oid[ i ].name;
+		argv[ 2 ] = s_oid[ i ].oid;
+
+		if ( parse_oidm( &c, 0, NULL ) != 0 ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_initialize: unable to add "
+				"objectIdentifier \"%s=%s\"\n",
+				s_oid[ i ].name, s_oid[ i ].oid );
+			return 1;
+		}
+	}
+
+	/* schema integration */
+	for ( i = 0; mat[ i ].schema; i++ ) {
+		int			code;
+		AttributeDescription **ad =
+			((AttributeDescription **)&(((char *)mi)[ mat[ i ].offset ]));
+
+		*ad = NULL;
+		code = register_at( mat[ i ].schema, ad, 0 );
+
+		if ( code ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_db_init: register_at failed\n" );
+			return -1;
+		}
+		(*ad)->ad_type->sat_flags |= mat[ i ].flags;
+	}
+
+	for ( i = 0; moc[ i ].schema; i++ ) {
+		int			code;
+		ObjectClass		**Oc =
+			((ObjectClass **)&(((char *)mi)[ moc[ i ].offset ]));
+
+		code = register_oc( moc[ i ].schema, Oc, 0 );
+		if ( code ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor_back_db_init: register_oc failed\n" );
+			return -1;
+		}
+		(*Oc)->soc_flags |= moc[ i ].flags;
+	}
+
+	bi->bi_controls = controls;
+
+	bi->bi_init = 0;
+	bi->bi_open = 0;
+	bi->bi_config = monitor_back_config;
+	bi->bi_close = 0;
+	bi->bi_destroy = 0;
+
+	bi->bi_db_init = monitor_back_db_init;
+#if 0
+	bi->bi_db_config = monitor_back_db_config;
+#endif
+	bi->bi_db_open = monitor_back_db_open;
+	bi->bi_db_close = 0;
+	bi->bi_db_destroy = monitor_back_db_destroy;
+
+	bi->bi_op_bind = monitor_back_bind;
+	bi->bi_op_unbind = 0;
+	bi->bi_op_search = monitor_back_search;
+	bi->bi_op_compare = monitor_back_compare;
+	bi->bi_op_modify = monitor_back_modify;
+	bi->bi_op_modrdn = 0;
+	bi->bi_op_add = 0;
+	bi->bi_op_delete = 0;
+	bi->bi_op_abandon = 0;
+
+	bi->bi_extended = 0;
+
+	bi->bi_entry_release_rw = monitor_back_release;
+	bi->bi_chk_referrals = 0;
+	bi->bi_operational = monitor_back_operational;
+
+	/*
+	 * hooks for slap tools
+	 */
+	bi->bi_tool_entry_open = 0;
+	bi->bi_tool_entry_close = 0;
+	bi->bi_tool_entry_first = 0;
+	bi->bi_tool_entry_first_x = 0;
+	bi->bi_tool_entry_next = 0;
+	bi->bi_tool_entry_get = 0;
+	bi->bi_tool_entry_put = 0;
+	bi->bi_tool_entry_reindex = 0;
+	bi->bi_tool_sync = 0;
+	bi->bi_tool_dn2id_get = 0;
+	bi->bi_tool_entry_modify = 0;
+
+	bi->bi_connection_init = 0;
+	bi->bi_connection_destroy = 0;
+
+	bi->bi_extra = (void *)&monitor_extra;
+
+	/*
+	 * configuration objectClasses (fake)
+	 */
+	bi->bi_cf_ocs = monitorocs;
+
+	rc = config_register_schema( monitorcfg, monitorocs );
+	if ( rc ) {
+		return rc;
+	}
+
+	return 0;
+}
+
+int
+monitor_back_db_init(
+	BackendDB	*be,
+	ConfigReply	*c)
+{
+	int			rc;
+	struct berval		dn = BER_BVC( SLAPD_MONITOR_DN ),
+				pdn,
+				ndn;
+	BackendDB		*be2;
+
+	monitor_subsys_t	*ms;
+
+	/*
+	 * database monitor can be defined once only
+	 */
+	if ( be_monitor != NULL ) {
+		if (c) {
+			snprintf(c->msg, sizeof(c->msg),"only one monitor database allowed");
+		}
+		return( -1 );
+	}
+	be_monitor = be;
+
+	/*
+	 * register subsys
+	 */
+	for ( ms = known_monitor_subsys; ms->mss_name != NULL; ms++ ) {
+		if ( monitor_back_register_subsys( ms ) ) {
+			return -1;
+		}
+	}
+
+	/* indicate system schema supported */
+	SLAP_BFLAGS(be) |= SLAP_BFLAG_MONITOR;
+
+	rc = dnPrettyNormal( NULL, &dn, &pdn, &ndn, NULL );
+	if( rc != LDAP_SUCCESS ) {
+		Debug( LDAP_DEBUG_ANY,
+			"unable to normalize/pretty monitor DN \"%s\" (%d)\n",
+			dn.bv_val, rc );
+		return -1;
+	}
+
+	ber_bvarray_add( &be->be_suffix, &pdn );
+	ber_bvarray_add( &be->be_nsuffix, &ndn );
+
+	/* NOTE: only one monitor database is allowed,
+	 * so we use static storage */
+	ldap_pvt_thread_mutex_init( &monitor_info.mi_cache_mutex );
+
+	be->be_private = &monitor_info;
+
+	be2 = select_backend( &ndn, 0 );
+	if ( be2 != be ) {
+		char	*type = be2->bd_info->bi_type;
+
+		if ( overlay_is_over( be2 ) ) {
+			slap_overinfo	*oi = (slap_overinfo *)be2->bd_info->bi_private;
+			type = oi->oi_orig->bi_type;
+		}
+
+		if (c) {
+			snprintf(c->msg, sizeof(c->msg),
+					"\"monitor\" database serving namingContext \"%s\" "
+					"is hidden by \"%s\" database serving namingContext \"%s\".\n",
+					pdn.bv_val, type, be2->be_nsuffix[ 0 ].bv_val );
+		}
+		return -1;
+	}
+
+	return 0;
+}
+
+static void
+monitor_back_destroy_limbo_entry(
+	entry_limbo_t	*el,
+	int		dispose )
+{
+	if ( el->el_e ) {
+		entry_free( el->el_e );
+	}
+	if ( el->el_a ) {
+		attrs_free( el->el_a );
+	}
+	if ( !BER_BVISNULL( &el->el_nbase ) ) {
+		ber_memfree( el->el_nbase.bv_val );
+	}
+	if ( !BER_BVISNULL( &el->el_filter ) ) {
+		ber_memfree( el->el_filter.bv_val );
+	}
+
+	/* NOTE: callbacks are not copied; so only free them
+	 * if disposing of */
+	if ( el->el_cb && dispose != 0 ) {
+		monitor_callback_t *next;
+
+		for ( ; el->el_cb; el->el_cb = next ) {
+			next = el->el_cb->mc_next;
+			if ( el->el_cb->mc_dispose ) {
+				el->el_cb->mc_dispose( &el->el_cb->mc_private );
+			}
+			ch_free( el->el_cb );
+		}
+	}
+
+	ch_free( el );
+}
+
+int
+monitor_back_db_open(
+	BackendDB	*be,
+	ConfigReply	*cr)
+{
+	monitor_info_t 		*mi = (monitor_info_t *)be->be_private;
+	struct monitor_subsys_t	**ms;
+	Entry 			*e, **ep, *root;
+	monitor_entry_t		*mp;
+	int			i;
+	struct berval		bv, rdn = BER_BVC(SLAPD_MONITOR_DN);
+	struct tm		tms;
+	static char		tmbuf[ LDAP_LUTIL_GENTIME_BUFSIZE ];
+	struct berval	desc[] = {
+		BER_BVC("This subtree contains monitoring/managing objects."),
+		BER_BVC("This object contains information about this server."),
+		BER_BVC("Most of the information is held in operational"
+		" attributes, which must be explicitly requested."),
+		BER_BVNULL };
+
+	int			retcode = 0;
+
+	assert( be_monitor != NULL );
+	if ( be != be_monitor ) {
+		be_monitor = be;
+	}
+
+	/*
+	 * Start
+	 */
+	ldap_pvt_gmtime( &starttime, &tms );
+	lutil_gentime( tmbuf, sizeof(tmbuf), &tms );
+
+	mi->mi_startTime.bv_val = tmbuf;
+	mi->mi_startTime.bv_len = strlen( tmbuf );
+
+	if ( BER_BVISEMPTY( &be->be_rootdn ) ) {
+		BER_BVSTR( &mi->mi_creatorsName, SLAPD_ANONYMOUS );
+		BER_BVSTR( &mi->mi_ncreatorsName, SLAPD_ANONYMOUS );
+	} else {
+		mi->mi_creatorsName = be->be_rootdn;
+		mi->mi_ncreatorsName = be->be_rootndn;
+	}
+
+	/*
+	 * creates the "cn=Monitor" entry 
+	 */
+	e = monitor_entry_stub( NULL, NULL, &rdn, mi->mi_oc_monitorServer,
+		NULL, NULL );
+
+	if ( e == NULL) {
+		Debug( LDAP_DEBUG_ANY,
+			"unable to create \"%s\" entry\n",
+			SLAPD_MONITOR_DN );
+		return( -1 );
+	}
+
+	attr_merge_normalize( e, slap_schema.si_ad_description, desc, NULL );
+
+	bv.bv_val = strchr( (char *) Versionstr, '$' );
+	if ( bv.bv_val != NULL ) {
+		char	*end;
+
+		bv.bv_val++;
+		for ( ; bv.bv_val[ 0 ] == ' '; bv.bv_val++ )
+			;
+
+		end = strchr( bv.bv_val, '$' );
+		if ( end != NULL ) {
+			end--;
+
+			for ( ; end > bv.bv_val && end[ 0 ] == ' '; end-- )
+				;
+
+			end++;
+
+			bv.bv_len = end - bv.bv_val;
+
+		} else {
+			bv.bv_len = strlen( bv.bv_val );
+		}
+
+		if ( attr_merge_normalize_one( e, mi->mi_ad_monitoredInfo,
+					&bv, NULL ) ) {
+			Debug( LDAP_DEBUG_ANY,
+				"unable to add monitoredInfo to \"%s\" entry\n",
+				SLAPD_MONITOR_DN );
+			return( -1 );
+		}
+	}
+
+	mp = monitor_entrypriv_create();
+	if ( mp == NULL ) {
+		return -1;
+	}
+	e->e_private = ( void * )mp;
+	ep = &mp->mp_children;
+
+	if ( monitor_cache_add( mi, e ) ) {
+		Debug( LDAP_DEBUG_ANY,
+			"unable to add entry \"%s\" to cache\n",
+			SLAPD_MONITOR_DN );
+		return -1;
+	}
+	root = e;
+
+	/*	
+	 * Create all the subsystem specific entries
+	 */
+	for ( i = 0; monitor_subsys[ i ] != NULL; i++ ) {
+		int 		len = strlen( monitor_subsys[ i ]->mss_name );
+		struct berval	dn;
+		int		rc;
+
+		dn.bv_len = len + sizeof( "cn=" ) - 1;
+		dn.bv_val = ch_calloc( sizeof( char ), dn.bv_len + 1 );
+		strcpy( dn.bv_val, "cn=" );
+		strcat( dn.bv_val, monitor_subsys[ i ]->mss_name );
+		rc = dnPretty( NULL, &dn, &monitor_subsys[ i ]->mss_rdn, NULL );
+		free( dn.bv_val );
+		if ( rc != LDAP_SUCCESS ) {
+			Debug( LDAP_DEBUG_ANY,
+				"monitor RDN \"%s\" is invalid\n", 
+				dn.bv_val );
+			return( -1 );
+		}
+
+		e = monitor_entry_stub( &root->e_name, &root->e_nname,
+			&monitor_subsys[ i ]->mss_rdn, mi->mi_oc_monitorContainer,
+			NULL, NULL );
+
+		if ( e == NULL) {
+			Debug( LDAP_DEBUG_ANY,
+				"unable to create \"%s\" entry\n", 
+				monitor_subsys[ i ]->mss_dn.bv_val );
+			return( -1 );
+		}
+		monitor_subsys[i]->mss_dn = e->e_name;
+		monitor_subsys[i]->mss_ndn = e->e_nname;
+
+		if ( !BER_BVISNULL( &monitor_subsys[ i ]->mss_desc[ 0 ] ) ) {
+			attr_merge_normalize( e, slap_schema.si_ad_description,
+					monitor_subsys[ i ]->mss_desc, NULL );
+		}
+
+		mp = monitor_entrypriv_create();
+		if ( mp == NULL ) {
+			return -1;
+		}
+		e->e_private = ( void * )mp;
+		mp->mp_info = monitor_subsys[ i ];
+		mp->mp_flags = monitor_subsys[ i ]->mss_flags;
+
+		if ( monitor_cache_add( mi, e ) ) {
+			Debug( LDAP_DEBUG_ANY,
+				"unable to add entry \"%s\" to cache\n",
+				monitor_subsys[ i ]->mss_dn.bv_val );
+			return -1;
+		}
+
+		*ep = e;
+		ep = &mp->mp_next;
+	}
+
+	assert( be != NULL );
+
+	be->be_private = mi;
+	
+	/*
+	 * opens the monitor backend subsystems
+	 */
+	for ( ms = monitor_subsys; ms[ 0 ] != NULL; ms++ ) {
+		if ( ms[ 0 ]->mss_open && ms[ 0 ]->mss_open( be, ms[ 0 ] ) ) {
+			return( -1 );
+		}
+		ms[ 0 ]->mss_flags |= MONITOR_F_OPENED;
+	}
+
+	monitor_subsys_opened = 1;
+
+	if ( mi->mi_entry_limbo ) {
+		entry_limbo_t	*el = mi->mi_entry_limbo;
+
+		for ( ; el; ) {
+			entry_limbo_t	*tmp;
+			int		rc;
+
+			switch ( el->el_type ) {
+			case LIMBO_ENTRY:
+				rc = monitor_back_register_entry(
+						el->el_e,
+						el->el_cb,
+						el->el_mss,
+						el->el_flags );
+				break;
+
+			case LIMBO_ENTRY_PARENT:
+				rc = monitor_back_register_entry_parent(
+						el->el_e,
+						el->el_cb,
+						el->el_mss,
+						el->el_flags,
+						&el->el_nbase,
+						el->el_scope,
+						&el->el_filter );
+				break;
+				
+
+			case LIMBO_ATTRS:
+				rc = monitor_back_register_entry_attrs(
+						el->el_ndn,
+						el->el_a,
+						el->el_cb,
+						&el->el_nbase,
+						el->el_scope,
+						&el->el_filter );
+				break;
+
+			case LIMBO_CB:
+				rc = monitor_back_register_entry_callback(
+						el->el_ndn,
+						el->el_cb,
+						&el->el_nbase,
+						el->el_scope,
+						&el->el_filter );
+				break;
+
+			case LIMBO_BACKEND:
+				rc = monitor_back_register_backend( el->el_bi );
+				break;
+
+			case LIMBO_DATABASE:
+				rc = monitor_back_register_database( el->el_be, el->el_ndn );
+				break;
+
+			case LIMBO_OVERLAY_INFO:
+				rc = monitor_back_register_overlay_info( el->el_on );
+				break;
+
+			case LIMBO_OVERLAY:
+				rc = monitor_back_register_overlay( el->el_be, el->el_on, el->el_ndn );
+				break;
+
+			case LIMBO_SUBSYS:
+				rc = monitor_back_register_subsys( el->el_mss );
+				break;
+
+			default:
+				assert( 0 );
+			}
+
+			tmp = el;
+			el = el->el_next;
+			monitor_back_destroy_limbo_entry( tmp, rc );
+
+			if ( rc != 0 ) {
+				/* try all, but report error at end */
+				retcode = 1;
+			}
+		}
+
+		mi->mi_entry_limbo = NULL;
+	}
+
+	return retcode;
+}
+
+int
+monitor_back_config(
+	BackendInfo	*bi,
+	const char	*fname,
+	int		lineno,
+	int		argc,
+	char		**argv )
+{
+	/*
+	 * eventually, will hold backend specific configuration parameters
+	 */
+	return SLAP_CONF_UNKNOWN;
+}
+
+#if 0
+int
+monitor_back_db_config(
+	Backend     *be,
+	const char  *fname,
+	int         lineno,
+	int         argc,
+	char        **argv )
+{
+	monitor_info_t	*mi = ( monitor_info_t * )be->be_private;
+
+	/*
+	 * eventually, will hold database specific configuration parameters
+	 */
+	return SLAP_CONF_UNKNOWN;
+}
+#endif
+
+int
+monitor_back_db_destroy(
+	BackendDB	*be,
+	ConfigReply	*cr)
+{
+	monitor_info_t	*mi = ( monitor_info_t * )be->be_private;
+
+	if ( mi == NULL ) {
+		return -1;
+	}
+
+	/*
+	 * FIXME: destroys all the data
+	 */
+	/* NOTE: mi points to static storage; don't free it */
+	
+	(void)monitor_cache_destroy( mi );
+
+	if ( monitor_subsys ) {
+		int	i;
+
+		for ( i = 0; monitor_subsys[ i ] != NULL; i++ ) {
+			if ( monitor_subsys[ i ]->mss_destroy ) {
+				monitor_subsys[ i ]->mss_destroy( be, monitor_subsys[ i ] );
+			}
+
+			if ( !BER_BVISNULL( &monitor_subsys[ i ]->mss_rdn ) ) {
+				ch_free( monitor_subsys[ i ]->mss_rdn.bv_val );
+			}
+		}
+
+		ch_free( monitor_subsys );
+	}
+
+	if ( mi->mi_entry_limbo ) {
+		entry_limbo_t	*el = mi->mi_entry_limbo;
+
+		for ( ; el; ) {
+			entry_limbo_t *tmp = el;
+			el = el->el_next;
+			monitor_back_destroy_limbo_entry( tmp, 1 );
+		}
+	}
+	
+	ldap_pvt_thread_mutex_destroy( &monitor_info.mi_cache_mutex );
+
+	be->be_private = NULL;
+
+	return 0;
+}