cleanup: ha_checktype()

* error reporting was never needed
* avoid useless transformaton hton to db_type to hton
* in many cases the engine was guaranteed to exist, add asserts
* use ha_default_handlerton() instead of ha_checktype(DB_TYPE_DEFAULT)

mysql-test/r/partition_not_blackhole.result

@@ -9,7 +9,7 @@ SHOW TABLES;
 Tables_in_test
 t1
 SHOW CREATE TABLE t1;
-ERROR HY000: Incorrect information in file: './test/t1.frm'
+ERROR HY000: Failed to read from the .par file
 DROP TABLE t1;
 ERROR 42S02: Unknown table 'test.t1'
 t1.frm

mysql-test/t/partition_not_blackhole.test

@@ -17,7 +17,7 @@ let $MYSQLD_DATADIR= `SELECT @@datadir`;
 --copy_file std_data/parts/t1_blackhole.par $MYSQLD_DATADIR/test/t1.par
 SHOW TABLES;
 --replace_result $MYSQLD_DATADIR ./
---error ER_NOT_FORM_FILE
+--error ER_FAILED_READ_FROM_PAR_FILE
 SHOW CREATE TABLE t1;
 --error ER_BAD_TABLE_ERROR
 DROP TABLE t1;

sql/handler.cc

@@ -231,24 +231,13 @@ handlerton *ha_resolve_by_legacy_type(THD *thd, enum legacy_db_type db_type)
 /**
   Use other database handler if databasehandler is not compiled in.
 */
-handlerton *ha_checktype(THD *thd, enum legacy_db_type database_type,
-                          bool no_substitute, bool report_error)
+handlerton *ha_checktype(THD *thd, handlerton *hton, bool no_substitute)
 {
-  handlerton *hton= ha_resolve_by_legacy_type(thd, database_type);
   if (ha_storage_engine_is_enabled(hton))
     return hton;
 
   if (no_substitute)
-  {
-    if (report_error)
-    {
-      const char *engine_name= ha_resolve_storage_engine_name(hton);
-      my_error(ER_FEATURE_DISABLED,MYF(0),engine_name,engine_name);
-    }
     return NULL;
-  }
-
-  (void) RUN_HOOK(transaction, after_rollback, (thd, FALSE));
 
   return ha_default_handlerton(thd);
 } /* ha_checktype */

sql/handler.h

@@ -4061,9 +4061,13 @@ plugin_ref ha_lock_engine(THD *thd, const handlerton *hton);
 handlerton *ha_resolve_by_legacy_type(THD *thd, enum legacy_db_type db_type);
 handler *get_new_handler(TABLE_SHARE *share, MEM_ROOT *alloc,
                          handlerton *db_type);
-handlerton *ha_checktype(THD *thd, enum legacy_db_type database_type,
-                          bool no_substitute, bool report_error);
+handlerton *ha_checktype(THD *thd, handlerton *hton, bool no_substitute);
 
+static inline handlerton *ha_checktype(THD *thd, enum legacy_db_type type,
+                                       bool no_substitute = 0)
+{
+  return ha_checktype(thd, ha_resolve_by_legacy_type(thd, type), no_substitute);
+}
 
 static inline enum legacy_db_type ha_legacy_type(const handlerton *db_type)
 {

sql/sql_table.cc

@@ -4452,8 +4452,7 @@ handler *mysql_create_frm_image(THD *thd,
       {
         if (part_info->default_engine_type == NULL)
         {
-          part_info->default_engine_type= ha_checktype(thd,
-                                          DB_TYPE_DEFAULT, 0, 0);
+          part_info->default_engine_type= ha_default_handlerton(thd);
         }
       }
     }
@@ -9748,10 +9747,10 @@ static bool check_engine(THD *thd, const char *db_name,
   DBUG_ENTER("check_engine");
   handlerton **new_engine= &create_info->db_type;
   handlerton *req_engine= *new_engine;
-  bool no_substitution=
-        MY_TEST(thd->variables.sql_mode & MODE_NO_ENGINE_SUBSTITUTION);
-  if (!(*new_engine= ha_checktype(thd, ha_legacy_type(req_engine),
-                                  no_substitution, 1)))
+  bool no_substitution= thd->variables.sql_mode & MODE_NO_ENGINE_SUBSTITUTION;
+  *new_engine= ha_checktype(thd, req_engine, no_substitution);
+  DBUG_ASSERT(*new_engine);
+  if (!*new_engine)
     DBUG_RETURN(true);
 
   if (req_engine && req_engine != *new_engine)

sql/table.cc

@@ -1047,8 +1047,7 @@ int TABLE_SHARE::init_from_binary_frm_image(THD *thd, bool write,
   if (frm_image[61] && !share->default_part_plugin)
   {
     enum legacy_db_type db_type= (enum legacy_db_type) (uint) frm_image[61];
-    share->default_part_plugin=
-                ha_lock_engine(NULL, ha_checktype(thd, db_type, 1, 0));
+    share->default_part_plugin= ha_lock_engine(NULL, ha_checktype(thd, db_type));
     if (!share->default_part_plugin)
       goto err;
   }
@@ -1060,7 +1059,7 @@ int TABLE_SHARE::init_from_binary_frm_image(THD *thd, bool write,
   */
   if (legacy_db_type > DB_TYPE_UNKNOWN && 
       legacy_db_type < DB_TYPE_FIRST_DYNAMIC)
-    se_plugin= ha_lock_engine(NULL, ha_checktype(thd, legacy_db_type, 0, 0));
+    se_plugin= ha_lock_engine(NULL, ha_checktype(thd, legacy_db_type));
   share->db_create_options= db_create_options= uint2korr(frm_image+30);
   share->db_options_in_use= share->db_create_options;
   share->mysql_version= uint4korr(frm_image+51);
@@ -3305,8 +3304,8 @@ void prepare_frm_header(THD *thd, uint reclength, uchar *fileinfo,
   fileinfo[1]= 1;
   fileinfo[2]= FRM_VER + 3 + MY_TEST(create_info->varchar);
 
-  fileinfo[3]= (uchar) ha_legacy_type(
-        ha_checktype(thd,ha_legacy_type(create_info->db_type),0,0));
+  DBUG_ASSERT(ha_storage_engine_is_enabled(create_info->db_type));
+  fileinfo[3]= (uchar) ha_legacy_type(create_info->db_type);
 
   /*
     Keep in sync with pack_keys() in unireg.cc