BUG#48506 crash in CREATE TABLE IF NOT EXISTS <existing_view> LIKE

<tmp_tbl> with RBL

When binlogging the statement, the server always handle the existing
object as a table, even though it is a view. However a view is
handled differently in other parts of the code thus leading the
statement to crash in RBL if the view exists.

This happens because the underlying tables for the view are not opened
when we try to call store_create_info() on the view in order to build
a CREATE TABLE statement.

This patch will only address the crash problem, other binlogging
problems related to CREATE TABLE IF NOT EXISTS LIKE when the existing
object is a view will be solved by BUG 47442.

mysql-test/suite/rpl/r/rpl_row_create_table.result

@@ -476,4 +476,30 @@ master-bin.000001	#	Table_map	#	#	table_id: # (mysqltest1.with_select)
 master-bin.000001	#	Write_rows	#	#	table_id: # flags: STMT_END_F
 master-bin.000001	#	Query	#	#	COMMIT
 DROP DATABASE mysqltest1;
+stop slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+reset master;
+reset slave;
+drop table if exists t1,t2,t3,t4,t5,t6,t7,t8,t9;
+start slave;
+CREATE TEMPORARY TABLE t7(c1 INT);
+CREATE TABLE t5(c1 INT);
+CREATE TABLE t4(c1 INT);
+CREATE VIEW bug48506_t1 AS SELECT 1;
+CREATE VIEW bug48506_t2 AS SELECT * FROM t4;
+CREATE VIEW bug48506_t3 AS SELECT t5.c1 AS A, t4.c1 AS B FROM t5, t4;
+CREATE TABLE bug48506_t4(c1 INT);
+DROP VIEW bug48506_t1, bug48506_t2, bug48506_t3;
+DROP TABLE bug48506_t4;
+CREATE TABLE IF NOT EXISTS bug48506_t1 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t2 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t3 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t4 LIKE t7;
+SHOW TABLES LIKE 'bug48506%';
+Tables_in_test (bug48506%)
+bug48506_t4
+DROP VIEW IF EXISTS bug48506_t1, bug48506_t2, bug48506_t3;
+DROP TEMPORARY TABLES t7;
+DROP TABLES t4, t5;
+DROP TABLES IF EXISTS bug48506_t4;
 end of the tests

mysql-test/suite/rpl/t/rpl_row_create_table.test

@@ -292,4 +292,40 @@ connection master;
 DROP DATABASE mysqltest1;
 sync_slave_with_master;
 
+#
+# BUG#48506: crash in CREATE TABLE <existing_view> IF NOT EXISTS LIKE
+# <tmp_tbl> with RBL
+#
+
+source include/master-slave-reset.inc;
+
+connection master;
+CREATE TEMPORARY TABLE t7(c1 INT);
+CREATE TABLE t5(c1 INT);
+CREATE TABLE t4(c1 INT);
+CREATE VIEW bug48506_t1 AS SELECT 1;
+CREATE VIEW bug48506_t2 AS SELECT * FROM t4;
+CREATE VIEW bug48506_t3 AS SELECT t5.c1 AS A, t4.c1 AS B FROM t5, t4;
+CREATE TABLE bug48506_t4(c1 INT);
+--disable_warnings
+sync_slave_with_master;
+DROP VIEW bug48506_t1, bug48506_t2, bug48506_t3;
+DROP TABLE bug48506_t4;
+
+connection master;
+CREATE TABLE IF NOT EXISTS bug48506_t1 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t2 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t3 LIKE t7;
+CREATE TABLE IF NOT EXISTS bug48506_t4 LIKE t7;
+--enable_warnings
+sync_slave_with_master;
+
+SHOW TABLES LIKE 'bug48506%';
+
+connection master;
+DROP VIEW IF EXISTS bug48506_t1, bug48506_t2, bug48506_t3;
+DROP TEMPORARY TABLES t7;
+DROP TABLES t4, t5;
+DROP TABLES IF EXISTS bug48506_t4;
+source include/master-slave-end.inc;
 --echo end of the tests

sql/sql_table.cc

@@ -5419,12 +5419,20 @@ goto binlog;
         }
         VOID(pthread_mutex_unlock(&LOCK_open));
 
-        IF_DBUG(int result=)
-          store_create_info(thd, table, &query,
-                            create_info, FALSE /* show_database */);
+       /*
+         The condition avoids a crash as described in BUG#48506. Other
+         binlogging problems related to CREATE TABLE IF NOT EXISTS LIKE
+         when the existing object is a view will be solved by BUG 47442.
+       */
+        if (!table->view)
+        {
+          IF_DBUG(int result=)
+            store_create_info(thd, table, &query,
+                              create_info, FALSE /* show_database */);
 
-        DBUG_ASSERT(result == 0); // store_create_info() always return 0
-        write_bin_log(thd, TRUE, query.ptr(), query.length());
+          DBUG_ASSERT(result == 0); // store_create_info() always return 0
+          write_bin_log(thd, TRUE, query.ptr(), query.length());
+        }
       }
       else                                      // Case 1
         write_bin_log(thd, TRUE, thd->query(), thd->query_length());