From 6946341b5d2a9a65ebcadcf31410f5578fefd552 Mon Sep 17 00:00:00 2001

From: Mark Reynolds <mreynolds@redhat.com>

Date: Fri, 9 Jan 2015 13:53:20 -0500

Subject: [PATCH 298/305] Ticket 47973 - During schema reload sometimes the

 search  returns no results

Bug Description:  During a schema reload operation the search of an existing

                  entry may randomly report no results.  This is because during

                  the schema reload all existing attribute syntaxes are removed,

                  and there is a small window where ldap operations can be performed

                  before the new schema is loaded.  During this window, attribute

                  values are normalized to NULL which causes operation to unexpectedly

                  fail.

Fix Description:  Instead of wiping out the existing attribute syntax hastables

                  in the middle of the task, instead load the new schema into

                  temporary hash tables.  Once the reload is complete, then take

                  the asi write lock, remove the old hash tables, and swap in the

                  new ones.

https://fedorahosted.org/389/ticket/47973

valgrind: PASSED

Reviewed by: nhosoi(Thanks!)

(cherry picked from commit 3fafcbe0a2ada038f02efdfdce77c1768f0e1819)

Conflicts:

	ldap/servers/slapd/attrsyntax.c

	ldap/servers/slapd/proto-slap.h

(cherry picked from commit 457252f5c97aa8b72d94376e328e63c5d47a825b)

---

 ldap/servers/plugins/schema_reload/schema_reload.c |   7 -

 ldap/servers/slapd/attr.c                          |   8 +-

 ldap/servers/slapd/attrsyntax.c                    | 230 +++++++++++++++------

 ldap/servers/slapd/opshared.c                      |   2 +-

 ldap/servers/slapd/proto-slap.h                    |  12 +-

 ldap/servers/slapd/schema.c                        | 116 ++++++-----

 6 files changed, 243 insertions(+), 132 deletions(-)

diff --git a/ldap/servers/plugins/schema_reload/schema_reload.c b/ldap/servers/plugins/schema_reload/schema_reload.c

index efc0de2..4e5c7f0 100644

--- a/ldap/servers/plugins/schema_reload/schema_reload.c

+++ b/ldap/servers/plugins/schema_reload/schema_reload.c

@@ -170,13 +170,6 @@ schemareload_thread(void *arg)

             slapi_task_log_notice(task, "Schema reload task finished.");

             slapi_task_log_status(task, "Schema reload task finished.");

             slapi_log_error(SLAPI_LOG_FATAL, "schemareload", "Schema reload task finished.\n");

-

-            slapi_log_error(SLAPI_LOG_FATAL, "schemareload",

-                            "Register internal schema.\n");

-            rv = slapi_reload_internal_attr_syntax();

-            slapi_log_error(SLAPI_LOG_FATAL, "schemareload",

-                            "Register internal schema finished.\n");

-

         } else {

             slapi_task_log_notice(task, "Schema reload task failed.");

             slapi_task_log_status(task, "Schema reload task failed.");

diff --git a/ldap/servers/slapd/attr.c b/ldap/servers/slapd/attr.c

index 983e286..a4d8a96 100644

--- a/ldap/servers/slapd/attr.c

+++ b/ldap/servers/slapd/attr.c

@@ -175,8 +175,8 @@ slapi_attr_types_equivalent(const char *t1, const char *t2)

 		return 0;

 	}

-	asi1 = attr_syntax_get_by_name(t1);

-	asi2 = attr_syntax_get_by_name(t2);

+	asi1 = attr_syntax_get_by_name(t1, 0);

+	asi2 = attr_syntax_get_by_name(t2, 0);

 	if (NULL != asi1) {

 		if (NULL != asi2) {

 			/* Both found - compare normalized names */

@@ -277,7 +277,7 @@ slapi_attr_init_locking_optional(Slapi_Attr *a, const char *type, PRBool use_loc

 			{

 				basetype = tmp;	/* basetype was malloc'd */

 			}

-			asi = attr_syntax_get_by_name_locking_optional(basetype, use_lock);

+			asi = attr_syntax_get_by_name_locking_optional(basetype, use_lock, 0);

 		}

 		if(NULL == asi)

 		{

@@ -288,7 +288,7 @@ slapi_attr_init_locking_optional(Slapi_Attr *a, const char *type, PRBool use_loc

 			 * attribute type that has that syntax.

 			 */

 			asi = attr_syntax_get_by_name_locking_optional(

-					ATTR_WITH_OCTETSTRING_SYNTAX, use_lock);

+					ATTR_WITH_OCTETSTRING_SYNTAX, use_lock, 0);

 		}

 		else

 		{

diff --git a/ldap/servers/slapd/attrsyntax.c b/ldap/servers/slapd/attrsyntax.c

index 75114e0..d92728a 100644

--- a/ldap/servers/slapd/attrsyntax.c

+++ b/ldap/servers/slapd/attrsyntax.c

@@ -73,14 +73,19 @@ static Slapi_RWLock *name2asi_lock = NULL;

 #define AS_UNLOCK_READ(l)	slapi_rwlock_unlock(l)

 #define AS_UNLOCK_WRITE(l)	slapi_rwlock_unlock(l)

+/*

+ * For the schema reload task, we need to use separate temporary hashtables & linked lists

+ */

+static PLHashTable *oid2asi_tmp = NULL;

+static PLHashTable *name2asi_tmp = NULL;

 static struct asyntaxinfo *default_asi = NULL;

 static void *attr_syntax_get_plugin_by_name_with_default( const char *type );

 static void attr_syntax_delete_no_lock( struct asyntaxinfo *asip,

-		PRBool remove_from_oid_table );

+		PRBool remove_from_oid_table, PRUint32 schema_flags );

 static struct asyntaxinfo *attr_syntax_get_by_oid_locking_optional( const

-		char *oid, PRBool use_lock);

+		char *oid, PRBool use_lock, PRUint32 schema_flags);

 #ifdef ATTR_LDAP_DEBUG

 static void attr_syntax_print();

@@ -198,8 +203,6 @@ attr_syntax_check_oids()

 void

 attr_syntax_free( struct asyntaxinfo *a )

 {

-	PR_ASSERT( a->asi_refcnt == 0 );

-

 	cool_charray_free( a->asi_aliases );

 	slapi_ch_free( (void**)&a->asi_name );

 	slapi_ch_free( (void **)&a->asi_desc );

@@ -228,9 +231,9 @@ attr_syntax_new()

  * be returned by calling to attr_syntax_return().

  */

 struct asyntaxinfo *

-attr_syntax_get_by_oid(const char *oid)

+attr_syntax_get_by_oid(const char *oid, PRUint32 schema_flags)

 {

-	return attr_syntax_get_by_oid_locking_optional( oid, PR_TRUE);

+	return attr_syntax_get_by_oid_locking_optional( oid, PR_TRUE, schema_flags);

 }

@@ -243,15 +246,30 @@ attr_syntax_get_by_oid(const char *oid)

  * same use_lock parameter.

  */

 static struct asyntaxinfo *

-attr_syntax_get_by_oid_locking_optional( const char *oid, PRBool use_lock )

+attr_syntax_get_by_oid_locking_optional( const char *oid, PRBool use_lock, PRUint32 schema_flags )

 {

 	struct asyntaxinfo *asi = 0;

-	if (oid2asi)

+	PLHashTable *ht = oid2asi;

+	int using_tmp_ht = 0;

+

+	if (schema_flags & DSE_SCHEMA_LOCKED){

+		ht = oid2asi_tmp;

+		using_tmp_ht = 1;

+		use_lock = 0;

+	}

+	if (ht)

 	{

 		if ( use_lock ) {

 			AS_LOCK_READ(oid2asi_lock);

 		}

-		asi = (struct asyntaxinfo *)PL_HashTableLookup_const(oid2asi, oid);

+		if (!using_tmp_ht){

+			/*

+			 * The oid2asi pointer could have been rewritten by the schema_reload task

+			 * while waiting on the lock, so grab it again.

+			 */

+			ht = oid2asi;

+		}

+		asi = (struct asyntaxinfo *)PL_HashTableLookup_const(ht, oid);

 		if (asi)

 		{

 			PR_AtomicIncrement( &asi->asi_refcnt );

@@ -272,18 +290,22 @@ attr_syntax_get_by_oid_locking_optional( const char *oid, PRBool use_lock )

  * to worry about resource contention.

  */

 static void

-attr_syntax_add_by_oid(const char *oid, struct asyntaxinfo *a, int lock)

+attr_syntax_add_by_oid(const char *oid, struct asyntaxinfo *a, PRUint32 schema_flags, int lock)

 {

 	if (0 != attr_syntax_init()) return;

-	if (lock) {

-		AS_LOCK_WRITE(oid2asi_lock);

-	}

+	if(schema_flags & DSE_SCHEMA_LOCKED){

+		PL_HashTableAdd(oid2asi_tmp, oid, a);

+	} else {

+		if (lock) {

+			AS_LOCK_WRITE(oid2asi_lock);

+		}

-	PL_HashTableAdd(oid2asi, oid, a);

+		PL_HashTableAdd(oid2asi, oid, a);

-	if (lock) {

-		AS_UNLOCK_WRITE(oid2asi_lock);

+		if (lock) {

+			AS_UNLOCK_WRITE(oid2asi_lock);

+		}

 	}

 }

@@ -296,18 +318,19 @@ attr_syntax_add_by_oid(const char *oid, struct asyntaxinfo *a, int lock)

  * be returned by calling to attr_syntax_return().

  */

 struct asyntaxinfo *

-attr_syntax_get_by_name(const char *name)

+attr_syntax_get_by_name(const char *name, PRUint32 schema_flags)

 {

-	return attr_syntax_get_by_name_locking_optional(name, PR_TRUE);

+	return attr_syntax_get_by_name_locking_optional(name, PR_TRUE, schema_flags);

 }

 struct asyntaxinfo *

 attr_syntax_get_by_name_with_default(const char *name)

 {

 	struct asyntaxinfo *asi = NULL;

-	asi = attr_syntax_get_by_name_locking_optional(name, PR_TRUE);

+

+	asi = attr_syntax_get_by_name_locking_optional(name, PR_TRUE, 0);

 	if (asi == NULL)

-		asi = attr_syntax_get_by_name(ATTR_WITH_OCTETSTRING_SYNTAX);

+		asi = attr_syntax_get_by_name(ATTR_WITH_OCTETSTRING_SYNTAX, 0);

 	if ( asi == NULL ) 

 		asi = default_asi;

 	return asi;

@@ -322,15 +345,30 @@ attr_syntax_get_by_name_with_default(const char *name)

  * same use_lock parameter.

  */

 struct asyntaxinfo *

-attr_syntax_get_by_name_locking_optional(const char *name, PRBool use_lock)

+attr_syntax_get_by_name_locking_optional(const char *name, PRBool use_lock, PRUint32 schema_flags)

 {

 	struct asyntaxinfo *asi = 0;

-	if (name2asi)

+	PLHashTable *ht = name2asi;

+	int using_tmp_ht = 0;

+

+	if (schema_flags & DSE_SCHEMA_LOCKED){

+		ht = name2asi_tmp;

+		using_tmp_ht = 1;

+		use_lock = 0;

+	}

+	if (ht)

 	{

 		if ( use_lock ) {

 			AS_LOCK_READ(name2asi_lock);

 		}

-		asi = (struct asyntaxinfo *)PL_HashTableLookup_const(name2asi, name);

+		if(!using_tmp_ht){

+			/*

+			 * The name2asi pointer could have been rewritten by the schema_reload task

+			 * while waiting on the lock, so grab it again.

+			 */

+			ht = name2asi;

+		}

+		asi = (struct asyntaxinfo *)PL_HashTableLookup_const(ht, name);

 		if ( NULL != asi ) {

 			PR_AtomicIncrement( &asi->asi_refcnt );

 		}

@@ -339,7 +377,7 @@ attr_syntax_get_by_name_locking_optional(const char *name, PRBool use_lock)

 		}

 	}

 	if (!asi) /* given name may be an OID */

-		asi = attr_syntax_get_by_oid_locking_optional(name, use_lock);

+		asi = attr_syntax_get_by_oid_locking_optional(name, use_lock, schema_flags);

 	return asi;

 }

@@ -402,26 +440,37 @@ attr_syntax_return_locking_optional(struct asyntaxinfo *asi, PRBool use_lock)

  * to worry about resource contention.

  */

 static void

-attr_syntax_add_by_name(struct asyntaxinfo *a, int lock)

+attr_syntax_add_by_name(struct asyntaxinfo *a, PRUint32 schema_flags, int lock)

 {

 	if (0 != attr_syntax_init()) return;

-	if (lock) {

-		AS_LOCK_WRITE(name2asi_lock);

-	}

+	if (schema_flags & DSE_SCHEMA_LOCKED ){

+		PL_HashTableAdd(name2asi_tmp, a->asi_name, a);

+		if ( a->asi_aliases != NULL ) {

+			int i;

+

+			for ( i = 0; a->asi_aliases[i] != NULL; ++i ) {

+				PL_HashTableAdd(name2asi_tmp, a->asi_aliases[i], a);

+			}

+		}

+	} else {

+		if (lock) {

+			AS_LOCK_WRITE(name2asi_lock);

+		}

-	PL_HashTableAdd(name2asi, a->asi_name, a);

-	if ( a->asi_aliases != NULL ) {

-		int		i;

+		PL_HashTableAdd(name2asi, a->asi_name, a);

+		if ( a->asi_aliases != NULL ) {

+			int i;

-		for ( i = 0; a->asi_aliases[i] != NULL; ++i ) {

-			PL_HashTableAdd(name2asi, a->asi_aliases[i], a);

+			for ( i = 0; a->asi_aliases[i] != NULL; ++i ) {

+				PL_HashTableAdd(name2asi, a->asi_aliases[i], a);

+			}

+		}

+		if (lock) {

+			AS_UNLOCK_WRITE(name2asi_lock);

 		}

 	}

-	if (lock) {

-		AS_UNLOCK_WRITE(name2asi_lock);

-	}

 }

@@ -430,7 +479,7 @@ attr_syntax_add_by_name(struct asyntaxinfo *a, int lock)

  * and oids.

  */

 void

-attr_syntax_delete( struct asyntaxinfo *asi )

+attr_syntax_delete( struct asyntaxinfo *asi, PRUint32 schema_flags )

 {

 	PR_ASSERT( asi );

@@ -438,7 +487,7 @@ attr_syntax_delete( struct asyntaxinfo *asi )

 		AS_LOCK_WRITE(oid2asi_lock);

 		AS_LOCK_WRITE(name2asi_lock);

-		attr_syntax_delete_no_lock( asi, PR_TRUE );

+		attr_syntax_delete_no_lock( asi, PR_TRUE, schema_flags );

 		AS_UNLOCK_WRITE(name2asi_lock);

 		AS_UNLOCK_WRITE(oid2asi_lock);

@@ -452,19 +501,34 @@ attr_syntax_delete( struct asyntaxinfo *asi )

  */

 static void

 attr_syntax_delete_no_lock( struct asyntaxinfo *asi,

-		PRBool remove_from_oidtable )

+		PRBool remove_from_oidtable, PRUint32 schema_flags )

 {

-	int		i;

+	PLHashTable *ht = NULL;

+	int using_tmp_ht = 0;

+	int i;

+	if (schema_flags & DSE_SCHEMA_LOCKED){

+		using_tmp_ht = 1;

+	}

 	if (oid2asi && remove_from_oidtable ) {

-		PL_HashTableRemove(oid2asi, asi->asi_oid);

+		if (using_tmp_ht){

+			ht = oid2asi_tmp;

+		} else {

+			ht = oid2asi;

+		}

+		PL_HashTableRemove(ht, asi->asi_oid);

 	}

 	if(name2asi) {

-		PL_HashTableRemove(name2asi, asi->asi_name);

+		if (using_tmp_ht){

+			ht = name2asi_tmp;

+		} else {

+			ht = name2asi;

+		}

+		PL_HashTableRemove(ht, asi->asi_name);

 		if ( asi->asi_aliases != NULL ) {

 			for ( i = 0; asi->asi_aliases[i] != NULL; ++i ) {

-				PL_HashTableRemove(name2asi, asi->asi_aliases[i]);

+				PL_HashTableRemove(ht, asi->asi_aliases[i]);

 			}

 		}

 		if ( asi->asi_refcnt > 0 ) {

@@ -496,7 +560,7 @@ slapi_attr_syntax_normalize( const char *s )

 	struct asyntaxinfo *asi = NULL;

 	char *r = NULL;

-	if((asi=attr_syntax_get_by_name(s)) != NULL ) {

+	if((asi=attr_syntax_get_by_name(s, 0)) != NULL ) {

 		r = slapi_ch_strdup(asi->asi_name);

 		attr_syntax_return( asi );

 	}

@@ -507,7 +571,6 @@ slapi_attr_syntax_normalize( const char *s )

 	return r;

 }

-

 /*

  * attr_syntax_exists: return 1 if attr_name exists, 0 otherwise

  *

@@ -517,7 +580,8 @@ attr_syntax_exists(const char *attr_name)

 {

 	struct asyntaxinfo	*asi;

-	asi = attr_syntax_get_by_name(attr_name);

+

+	asi = attr_syntax_get_by_name(attr_name, 0);

 	attr_syntax_return( asi );

 	if ( asi != NULL )

@@ -686,13 +750,13 @@ attr_syntax_get_plugin_by_name_with_default( const char *type )

 	/*

 	 * first we look for this attribute type explictly

 	 */

-	if ( (asi = attr_syntax_get_by_name(type)) == NULL ) {

+	if ( (asi = attr_syntax_get_by_name(type, 0)) == NULL ) {

 		/*

 		 * no syntax for this type... return Octet String

 		 * syntax.  we accomplish this by looking up a well known

 		 * attribute type that has that syntax.

 		 */

-		asi = attr_syntax_get_by_name(ATTR_WITH_OCTETSTRING_SYNTAX);

+		asi = attr_syntax_get_by_name(ATTR_WITH_OCTETSTRING_SYNTAX, 0);

 		if (asi == NULL) 

 			asi = default_asi;

 	}

@@ -729,14 +793,13 @@ attr_syntax_dup( struct asyntaxinfo *a )

 	return( newas );

 }

-

 /*

  * Add a new attribute type to the schema.

  *

  * Returns an LDAP error code (LDAP_SUCCESS if all goes well).

  */

 int 

-attr_syntax_add( struct asyntaxinfo *asip )

+attr_syntax_add( struct asyntaxinfo *asip, PRUint32 schema_flags )

 {

 	int i, rc = LDAP_SUCCESS;

 	int nolock = asip->asi_flags & SLAPI_ATTR_FLAG_NOLOCKING;

@@ -748,7 +811,7 @@ attr_syntax_add( struct asyntaxinfo *asip )

 	/* make sure the oid is unique */

 	if ( NULL != ( oldas_from_oid = attr_syntax_get_by_oid_locking_optional(

-					asip->asi_oid, !nolock))) {

+					asip->asi_oid, !nolock, schema_flags))) {

 		if ( 0 == (asip->asi_flags & SLAPI_ATTR_FLAG_OVERRIDE)) {

 			/* failure - OID is in use; no override flag */

 			rc = LDAP_TYPE_OR_VALUE_EXISTS;

@@ -760,7 +823,7 @@ attr_syntax_add( struct asyntaxinfo *asip )

      * the primary name and OID point to the same schema definition.

 	 */

 	if ( NULL != ( oldas_from_name = attr_syntax_get_by_name_locking_optional(

-					asip->asi_name, !nolock))) {

+					asip->asi_name, !nolock, schema_flags))) {

 		if ( 0 == (asip->asi_flags & SLAPI_ATTR_FLAG_OVERRIDE)

 					|| ( oldas_from_oid != oldas_from_name )) {

 			/* failure; no override flag OR OID and name don't match */

@@ -768,7 +831,7 @@ attr_syntax_add( struct asyntaxinfo *asip )

 			goto cleanup_and_return;

 		}

 		/* Flag for deletion.  We are going to override this attr */

-		attr_syntax_delete(oldas_from_name);

+		attr_syntax_delete(oldas_from_name, schema_flags);

 	} else if ( NULL != oldas_from_oid ) {

 		/* failure - OID is in use but name does not exist */

 		rc = LDAP_TYPE_OR_VALUE_EXISTS;

@@ -782,11 +845,11 @@ attr_syntax_add( struct asyntaxinfo *asip )

 			if ( NULL != ( tmpasi =

 							attr_syntax_get_by_name_locking_optional(

-							asip->asi_aliases[i], !nolock))) {

+							asip->asi_aliases[i], !nolock, schema_flags))) {

 				if (asip->asi_flags & SLAPI_ATTR_FLAG_OVERRIDE) {

 					/* Flag for tmpasi for deletion.  It will be free'd

 					 * when attr_syntax_return is called. */

-					attr_syntax_delete(tmpasi);

+					attr_syntax_delete(tmpasi, schema_flags);

 				} else {

 					/* failure - one of the aliases is already in use */

 					rc = LDAP_TYPE_OR_VALUE_EXISTS;

@@ -805,8 +868,8 @@ attr_syntax_add( struct asyntaxinfo *asip )

 	/* ditto for the override one */

 	asip->asi_flags &= ~SLAPI_ATTR_FLAG_OVERRIDE;

-	attr_syntax_add_by_oid( asip->asi_oid, asip, !nolock);

-	attr_syntax_add_by_name( asip, !nolock);

+	attr_syntax_add_by_oid( asip->asi_oid, asip, schema_flags, !nolock);

+	attr_syntax_add_by_name( asip, schema_flags, !nolock);

 cleanup_and_return:

 	attr_syntax_return_locking_optional( oldas_from_oid, !nolock );

@@ -979,7 +1042,7 @@ slapi_attr_type2plugin( const char *type, void **pi )

 int

 slapi_attr_get_oid( const Slapi_Attr *a, char **oid )

 {

-	struct asyntaxinfo *asi = attr_syntax_get_by_name(a->a_type);

+	struct asyntaxinfo *asi = attr_syntax_get_by_name(a->a_type, 0);

 	if (asi) {

 		*oid = asi->asi_oid;

 		attr_syntax_return(asi);

@@ -995,7 +1058,7 @@ slapi_attr_get_oid( const Slapi_Attr *a, char **oid )

 int

 slapi_attr_get_oid_copy( const Slapi_Attr *a, char **oidp )

 {

-	struct asyntaxinfo *asi = attr_syntax_get_by_name(a->a_type);

+	struct asyntaxinfo *asi = attr_syntax_get_by_name(a->a_type, 0);

 	if (asi) {

 		*oidp = slapi_ch_strdup( asi->asi_oid );

 		attr_syntax_return(asi);

@@ -1191,7 +1254,7 @@ attr_syntax_delete_if_not_flagged(struct asyntaxinfo *asip, void *arg)

 	PR_ASSERT( fi != NULL );

 	if ( 0 == ( asip->asi_flags & fi->asef_flag )) {

-		attr_syntax_delete_no_lock( asip, PR_FALSE );

+		attr_syntax_delete_no_lock( asip, PR_FALSE, 0 );

 		return ATTR_SYNTAX_ENUM_REMOVE;

 	} else {

 		return ATTR_SYNTAX_ENUM_NEXT;

@@ -1207,7 +1270,7 @@ attr_syntax_force_to_delete(struct asyntaxinfo *asip, void *arg)

 	fi = (struct attr_syntax_enum_flaginfo *)arg;

 	PR_ASSERT( fi != NULL );

-	attr_syntax_delete_no_lock( asip, PR_FALSE );

+	attr_syntax_delete_no_lock( asip, PR_FALSE, 0 );

 	return ATTR_SYNTAX_ENUM_REMOVE;

 }

@@ -1272,6 +1335,7 @@ attr_syntax_delete_all_for_schemareload(unsigned long flag)

 #define ATTR_DEFAULT_SYNTAX_OID	"1.1"

 #define ATTR_DEFAULT_SYNTAX	"defaultdirstringsyntax"

+

 static int

 attr_syntax_init(void)

 {

@@ -1290,6 +1354,14 @@ attr_syntax_init(void)

 		}

 	}

+	if (!oid2asi_tmp)

+	{

+		/* temporary hash table for schema reload */

+		oid2asi_tmp = PL_NewHashTable(2047, hashNocaseString,

+		                              hashNocaseCompare,

+		                              PL_CompareValues, 0, 0);

+	}

+

 	if (!name2asi)

 	{

 		name2asi = PL_NewHashTable(2047, hashNocaseString,

@@ -1310,6 +1382,14 @@ attr_syntax_init(void)

 	                                DIRSTRING_SYNTAX_OID, 

 	                                SLAPI_ATTR_FLAG_NOUSERMOD );

 	}

+	if (!name2asi_tmp)

+	{

+		/* temporary hash table for schema reload */

+		name2asi_tmp = PL_NewHashTable(2047, hashNocaseString,

+		                               hashNocaseCompare,

+		                               PL_CompareValues, 0, 0);

+	}

+

 	return 0;

 }

@@ -1379,7 +1459,7 @@ slapi_add_internal_attr_syntax( const char *name, const char *oid,

 			 &asip );

 	if ( rc == LDAP_SUCCESS ) {

-		rc = attr_syntax_add( asip );

+		rc = attr_syntax_add( asip, 0 );

 		if ( rc == LDAP_SUCCESS ) {

 			if (attr_syntax_internal_asi_add_ht(asip)) {

 				slapi_log_error(SLAPI_LOG_FATAL,

@@ -1387,6 +1467,8 @@ slapi_add_internal_attr_syntax( const char *name, const char *oid,

 				                "Failed to stash internal asyntaxinfo: %s.\n",

 				                asip->asi_name);

 			}

+		} else {

+			attr_syntax_free(asip);

 		}

 	}

@@ -1406,7 +1488,7 @@ attr_syntax_internal_asi_add(struct asyntaxinfo *asip, void *arg)

 	/* Copy is needed since when reloading the schema,

 	 * existing syntax info is cleaned up. */

 	asip_copy = attr_syntax_dup(asip);

-	rc = attr_syntax_add(asip_copy);

+	rc = attr_syntax_add(asip_copy, 0);

 	if (LDAP_SUCCESS != rc) {

 		attr_syntax_free(asip_copy);

 	}

@@ -1426,3 +1508,25 @@ slapi_reload_internal_attr_syntax()

 	attr_syntax_enumerate_attrs_ext(internalasi, attr_syntax_internal_asi_add, NULL);

 	return rc;

 }

+

+/*

+ * schema reload - now that we have loaded the schema into temporary

+ * hash tables, swap out the old for the new.

+ */

+void

+attr_syntax_swap_ht()

+{

+	/* Remove the old hash tables */

+	PL_HashTableDestroy(name2asi);

+	PL_HashTableDestroy(oid2asi);

+

+	/*

+	 * Swap the hash table/linked list pointers, and set the

+	 * temporary pointers to NULL

+	 */

+	name2asi = name2asi_tmp;

+	name2asi_tmp = NULL;

+	oid2asi = oid2asi_tmp;

+	oid2asi_tmp = NULL;

+}

+

diff --git a/ldap/servers/slapd/opshared.c b/ldap/servers/slapd/opshared.c

index 7a0b544..a7367a7 100644

--- a/ldap/servers/slapd/opshared.c

+++ b/ldap/servers/slapd/opshared.c

@@ -91,7 +91,7 @@ int op_shared_is_allowed_attr (const char *attr_name, int replicated_op)

         struct asyntaxinfo    *asi;

         int                    no_user_mod = 0;

-        asi = attr_syntax_get_by_name( attr_name );

+        asi = attr_syntax_get_by_name( attr_name, 0 );

         if ( NULL != asi &&

                 0 != ( asi->asi_flags & SLAPI_ATTR_FLAG_NOUSERMOD ))

         {

diff --git a/ldap/servers/slapd/proto-slap.h b/ldap/servers/slapd/proto-slap.h

index 0891608..da9c925 100644

--- a/ldap/servers/slapd/proto-slap.h

+++ b/ldap/servers/slapd/proto-slap.h

@@ -117,7 +117,7 @@ void attr_syntax_write_lock(void);

 void attr_syntax_unlock_read(void);

 void attr_syntax_unlock_write(void);

 int attr_syntax_exists (const char *attr_name);

-void attr_syntax_delete ( struct asyntaxinfo *asip );

+void attr_syntax_delete ( struct asyntaxinfo *asip, PRUint32 schema_flags );

 #define SLAPI_SYNTAXLENGTH_NONE		(-1)	/* for syntaxlength parameter */

 int attr_syntax_create( const char *attr_oid, char *const*attr_names,

 		int num_names, const char *attr_desc, const char *attr_superior,

@@ -126,15 +126,17 @@ int attr_syntax_create( const char *attr_oid, char *const*attr_names,

 		const char *attr_syntax, int syntaxlength, unsigned long flags,

 		struct asyntaxinfo **asip );

 void attr_syntax_free( struct asyntaxinfo *a );

-int attr_syntax_add( struct asyntaxinfo *asip );

+int attr_syntax_add( struct asyntaxinfo *asip, PRUint32 schema_flags );

 char *attr_syntax_normalize_no_lookup( const char *s );

 void attr_syntax_enumerate_attrs(AttrEnumFunc aef, void *arg, PRBool writelock);

 void attr_syntax_all_clear_flag( unsigned long flag );

 void attr_syntax_delete_all_not_flagged( unsigned long flag );

-struct asyntaxinfo *attr_syntax_get_by_oid ( const char *oid );

-struct asyntaxinfo *attr_syntax_get_by_name ( const char *name );

-struct asyntaxinfo *attr_syntax_get_by_name_locking_optional ( const char *name, PRBool use_lock );

+struct asyntaxinfo *attr_syntax_get_by_oid ( const char *oid, PRUint32 schema_flags );

+struct asyntaxinfo *attr_syntax_get_by_name ( const char *name, PRUint32 schema_flags );

 struct asyntaxinfo *attr_syntax_get_by_name_with_default ( const char *name );

+struct asyntaxinfo *attr_syntax_get_by_name_locking_optional ( const char *name, PRBool use_lock, PRUint32 schema_flags );

+struct asyntaxinfo *attr_syntax_get_global_at();

+void attr_syntax_swap_ht(void);

 /*

  * Call attr_syntax_return() when you are done using a value returned

  * by attr_syntax_get_by_oid() or attr_syntax_get_by_name().

diff --git a/ldap/servers/slapd/schema.c b/ldap/servers/slapd/schema.c

index 18ae152..798d905 100644

--- a/ldap/servers/slapd/schema.c

+++ b/ldap/servers/slapd/schema.c

@@ -154,6 +154,8 @@ static int schema_strcmp( const char *s1, const char *s2 );

 static int schema_strcmp_array( char **sa1, char **sa2,

 		const char *ignorestr );

 static PRBool schema_type_is_interesting( const char *type );

+static void reload_schemafile_lock(void);

+static void reload_schemafile_unlock(void);

 static void schema_create_errormsg( char *errorbuf, size_t errorbufsize,

 		const char *prefix, const char *name, const char *fmt, ... )

 #ifdef __GNUC__ 

@@ -2125,7 +2127,7 @@ schema_delete_attributes ( Slapi_Entry *entryBefore, LDAPMod *mod,

 	sscanf (attr_ldif, "%s name %s syntax %s",

 			psbAttrOid->buffer, psbAttrName->buffer, psbAttrSyntax->buffer);

-	if ((a = attr_syntax_get_by_name ( psbAttrName->buffer)) != NULL ) {

+	if ((a = attr_syntax_get_by_name ( psbAttrName->buffer, 0 )) != NULL ) {

 	  /* only modify attrs which were user defined */

 	  if (a->asi_flags & SLAPI_ATTR_FLAG_STD_ATTR) {

 		schema_create_errormsg( errorbuf, errorbufsize, schema_errprefix_at,

@@ -2177,7 +2179,7 @@ schema_delete_attributes ( Slapi_Entry *entryBefore, LDAPMod *mod,

 	  }

 	  /* Delete it. */

-	  attr_syntax_delete( a );

+	  attr_syntax_delete( a, 0 );

 	  attr_syntax_return( a );

 	}

 	else {

@@ -2300,7 +2302,7 @@ add_oc_internal(struct objclass *pnew_oc, char *errorbuf, size_t errorbufsize,

 	}

 	/* check to see if the oid is already in use by an attribute */

-	if (!rc && (pasyntaxinfo = attr_syntax_get_by_oid(pnew_oc->oc_oid))) {

+	if (!rc && (pasyntaxinfo = attr_syntax_get_by_oid(pnew_oc->oc_oid, flags))) {

 		schema_create_errormsg( errorbuf, errorbufsize, schema_errprefix_oc,

 				pnew_oc->oc_name,

 				"The OID \"%s\" is also used by the attribute type \"%s\"",

@@ -2419,7 +2421,7 @@ schema_replace_attributes ( Slapi_PBlock *pb, LDAPMod *mod, char *errorbuf,

 		 * handle the various cases.

 		 */

 		if ( NULL == ( oldasip =

-					attr_syntax_get_by_oid( newasip->asi_oid ))) {

+					attr_syntax_get_by_oid( newasip->asi_oid, 0 ))) {

 			/* new attribute type */

 			LDAPDebug( LDAP_DEBUG_TRACE, "schema_replace_attributes:"

 					" new type %s (OID %s)\n",

@@ -2437,14 +2439,14 @@ schema_replace_attributes ( Slapi_PBlock *pb, LDAPMod *mod, char *errorbuf,

 						" replacing type %s (OID %s)\n",

 						newasip->asi_name, newasip->asi_oid, 0 );

 				/* flag for deletion */

-				attr_syntax_delete( oldasip );