fixed

BUG #2397 "RENAME TABLES is not blocked by FLUSH TABLES WITH READ LOCK"
(added waiting for global_read_lock in mysql_rename_tables)


mysql-test/r/rename.result:
  added test for 
  BUG #2397 "RENAME TABLES is not blocked by FLUSH TABLES WITH READ LOCK"
mysql-test/t/rename.test:
  added test for 
  BUG #2397 "RENAME TABLES is not blocked by FLUSH TABLES WITH READ LOCK"
sql/sql_rename.cc:
  fixed 
  BUG #2397 "RENAME TABLES is not blocked by FLUSH TABLES WITH READ LOCK"
  (added waiting for global_read_lock)

mysql-test/r/rename.result

@@ -39,3 +39,17 @@ select * from t3;
 drop table if exists t1,t2,t3,t4;
 Warnings:
 Note	1051	Unknown table 't4'
+CREATE TABLE t1 (a int);
+CREATE TABLE t3 (a int);
+FLUSH TABLES WITH READ LOCK;
+ RENAME TABLE t1 TO t2, t3 to t4;
+show tables;
+Tables_in_test
+t1
+t3
+UNLOCK TABLES;
+show tables;
+Tables_in_test
+t2
+t4
+drop table t2, t4;

mysql-test/t/rename.test

@@ -35,3 +35,27 @@ select * from t3;
 
 # This should give a warning for t4
 drop table if exists t1,t2,t3,t4;
+
+#
+# Test-case for Bug #2397 RENAME TABLES is not blocked by 
+#                                  FLUSH TABLES WITH READ LOCK
+#
+
+connect (con1,localhost,root,,);
+connect (con2,localhost,root,,);
+
+connection con1;
+CREATE TABLE t1 (a int);
+CREATE TABLE t3 (a int);
+connection con2;
+FLUSH TABLES WITH READ LOCK;
+connection con1;
+send RENAME TABLE t1 TO t2, t3 to t4;
+connection con2;
+sleep 1;
+show tables;
+UNLOCK TABLES;
+sleep 1;
+show tables;
+
+drop table t2, t4;

sql/sql_rename.cc

@@ -46,6 +46,8 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list)
     DBUG_RETURN(1);
   }
 
+  if (wait_if_global_read_lock(thd,0))
+    DBUG_RETURN(1);
   VOID(pthread_mutex_lock(&LOCK_open));
   if (lock_table_names(thd, table_list))
     goto err;
@@ -93,6 +95,7 @@ bool mysql_rename_tables(THD *thd, TABLE_LIST *table_list)
 
 err:
   pthread_mutex_unlock(&LOCK_open);
+  start_waiting_global_read_lock(thd);
   DBUG_RETURN(error);
 }