Patch: lru_mutex and c_rwlock bugs in back-bdb/cache.c  (ITS#1756)

			================
Written by Hallvard B. Furuseth and placed into the public domain.
This software is not subject to any license of the University of Oslo.
			================

The first ldap_pvt_thread_mutex_unlock() in bdb_cache_add_entry_rw()
should be ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );

Also, bdb's mutexes and rdwr locks are never destroyed.

Here is a patch.

Hallvard B. Furuseth <h.b.furuseth@usit.uio.no>, April 2002.


diff -u2 -r servers/slapd/back-bdb/cache.c~ servers/slapd/back-bdb/cache.c
--- servers/slapd/back-bdb/cache.c~	Mon Apr 15 18:53:24 2002
+++ servers/slapd/back-bdb/cache.c	Tue Apr 16 05:59:18 2002
@@ -168,5 +168,5 @@
 	int refcnt, freeit = 1;
 
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
 
@@ -194,5 +194,5 @@
 		BEI(e)->bei_state = CACHE_ENTRY_READY;
 
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
@@ -210,5 +210,5 @@
 	} else if ( BEI(e)->bei_state == CACHE_ENTRY_DELETED ) {
 		if( refcnt > 0 ) {
-			/* free cache mutex */
+			/* free cache lock */
 			ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
@@ -229,5 +229,5 @@
 			}
 
-			/* free cache mutex */
+			/* free cache lock */
 			ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
@@ -244,5 +244,5 @@
 
 	} else {
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
@@ -305,5 +305,5 @@
 		   e->e_dn, rw ? "w" : "r" ));
 #endif
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
 
@@ -311,6 +311,6 @@
 
 	if( bdb_cache_entry_private_init(e) != 0 ) {
-		/* free cache mutex */
-		ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
+		/* free cache lock */
+		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
 #ifdef NEW_LOGGING
@@ -331,5 +331,5 @@
 		(AVL_CMP) entry_dn_cmp, avl_dup_error ) != 0 )
 	{
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 
@@ -379,5 +379,5 @@
 		bdb_cache_entry_private_destroy(e);
 
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 		return( -1 );
@@ -451,5 +451,5 @@
 	Entry	*ee;
 
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
 
@@ -469,5 +469,5 @@
 #endif
 
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 		return( 1 );
@@ -502,5 +502,5 @@
 		}
 
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 		return( -1 );
@@ -572,5 +572,5 @@
 
 try_again:
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_rlock( &cache->c_rwlock );
 
@@ -599,5 +599,5 @@
 			assert(state != CACHE_ENTRY_UNDEFINED);
 
-			/* free cache mutex */
+			/* free cache lock */
 			ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
 
@@ -639,5 +639,5 @@
 
 	} else {
-		/* free cache mutex */
+		/* free cache lock */
 		ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
 
@@ -666,5 +666,5 @@
 
 try_again:
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_rlock( &cache->c_rwlock );
 
@@ -689,5 +689,5 @@
 			assert(state != CACHE_ENTRY_UNDEFINED);
 
-			/* free cache mutex */
+			/* free cache lock */
 			ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
 
@@ -714,5 +714,5 @@
 			 */
 
-			/* free cache mutex */
+			/* free cache lock */
 			ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
 
@@ -756,5 +756,5 @@
 	}
 
-	/* free cache mutex */
+	/* free cache lock */
 	ldap_pvt_thread_rdwr_runlock( &cache->c_rwlock );
 
@@ -781,5 +781,5 @@
 	int	rc;
 
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
 
@@ -798,5 +798,5 @@
 	ldap_pvt_thread_mutex_unlock( &cache->lru_mutex );
 
-	/* free cache mutex */
+	/* free cache lock */
 	ldap_pvt_thread_rdwr_wunlock( &cache->c_rwlock );
 	return( rc );
@@ -847,5 +847,5 @@
 	int rc;
 
-	/* set cache mutex */
+	/* set cache lock */
 	ldap_pvt_thread_rdwr_wlock( &cache->c_rwlock );
 	ldap_pvt_thread_mutex_lock( &cache->lru_mutex );
diff -u2 -r servers/slapd/back-bdb/init.c~ servers/slapd/back-bdb/init.c
--- servers/slapd/back-bdb/init.c~	Mon Apr 15 18:53:24 2002
+++ servers/slapd/back-bdb/init.c	Tue Apr 16 05:50:58 2002
@@ -444,4 +444,12 @@
 	}
 
+#ifdef BDB_HIER
+	ldap_pvt_thread_rdwr_destroy( &bdb->bi_tree_rdwr );
+#endif
+	ldap_pvt_thread_rdwr_destroy ( &bdb->bi_cache.c_rwlock );
+	ldap_pvt_thread_mutex_destroy( &bdb->bi_cache.lru_mutex );
+	ldap_pvt_thread_mutex_destroy( &bdb->bi_lastid_mutex );
+	ldap_pvt_thread_mutex_destroy( &bdb->bi_database_mutex );
+
 	return 0;
 }