MDEV-5438 A view can mask a table that supports discovery

mysql-test/suite/archive/discover_5438.result

+create table t1 (a int) engine=archive;
+create view t1 as select "I am a view" as a;
+ERROR 42S01: Table 't1' already exists
+drop table t1;
+create table t1 (a int) engine=archive;
+grant select on test.t1 to foo@bar;
+drop user foo@bar;
+drop table t1;
+create table t1 (a int) engine=archive;
+create table t2 (a int);
+alter table t2 rename t1;
+ERROR 42S01: Table 't1' already exists
+drop table t2, t1;

mysql-test/suite/archive/discover_5438.test

+#
+# MDEV-5438 - A view can mask a table that supports discovery
+#
+# in a few places the server was still using !access(path, F_OK) to
+# determine whether a table exists
+#
+source include/have_archive.inc;
+
+create table t1 (a int) engine=archive;
+--error ER_TABLE_EXISTS_ERROR
+create view t1 as select "I am a view" as a;
+drop table t1;
+
+create table t1 (a int) engine=archive;
+grant select on test.t1 to foo@bar;
+drop user foo@bar;
+drop table t1;
+
+create table t1 (a int) engine=archive;
+create table t2 (a int);
+--error ER_TABLE_EXISTS_ERROR
+alter table t2 rename t1;
+drop table t2, t1;
+
+

sql/sql_acl.cc

@@ -5413,12 +5413,7 @@ int mysql_table_grant(THD *thd, TABLE_LIST *table_list,
     {
       if (!(rights & CREATE_ACL))
       {
-        char buf[FN_REFLEN + 1];
-        build_table_filename(buf, sizeof(buf) - 1, table_list->db,
-                             table_list->table_name, reg_ext, 0);
-        fn_format(buf, buf, "", "", MY_UNPACK_FILENAME  | MY_RESOLVE_SYMLINKS |
-                                    MY_RETURN_REAL_PATH | MY_APPEND_EXT);
-        if (access(buf,F_OK))
+        if (!ha_table_exists(thd, table_list->db, table_list->table_name, 0))
         {
           my_error(ER_NO_SUCH_TABLE, MYF(0), table_list->db, table_list->alias);
           DBUG_RETURN(TRUE);

sql/sql_table.cc

@@ -7840,7 +7840,7 @@ bool mysql_alter_table(THD *thd,char *new_db, char *new_name,
         Table maybe does not exist, but we got an exclusive lock
         on the name, now we can safely try to find out for sure.
       */
-      if (!access(alter_ctx.get_new_filename(), F_OK))
+      if (ha_table_exists(thd, alter_ctx.new_db, alter_ctx.new_name, 0))
       {
         /* Table will be closed in do_command() */
         my_error(ER_TABLE_EXISTS_ERROR, MYF(0), alter_ctx.new_alias);

sql/sql_view.cc

@@ -908,7 +908,7 @@ static int mysql_register_view(THD *thd, TABLE_LIST *view,
     fn_format(path_buff, file.str, dir.str, "", MY_UNPACK_FILENAME);
     path.length= strlen(path_buff);
 
-    if (!access(path.str, F_OK))
+    if (ha_table_exists(thd, view->db, view->table_name, NULL))
     {
       if (mode == VIEW_CREATE_NEW)
       {