Bug#49501 Inefficient information_schema check (system collation), addon

removed wrongly introduced strlen calls

sql/events.cc

@@ -871,8 +871,7 @@ Events::fill_schema_events(THD *thd, TABLE_LIST *tables, COND * /* cond */)
   if (thd->lex->sql_command == SQLCOM_SHOW_EVENTS)
   {
     DBUG_ASSERT(thd->lex->select_lex.db);
-    if (!is_schema_db(thd->lex->select_lex.db,   // There is no events in I_S
-                      strlen(thd->lex->select_lex.db)) &&
+    if (!is_schema_db(thd->lex->select_lex.db) &&    // There is no events in I_S
         check_access(thd, EVENT_ACL, thd->lex->select_lex.db, 0, 0, 0, 0))
       DBUG_RETURN(1);
     db= thd->lex->select_lex.db;

sql/mysql_priv.h

@@ -1426,6 +1426,12 @@ inline bool is_schema_db(const char *name, size_t len)
                          INFORMATION_SCHEMA_NAME.str, name));  
 }
 
+inline bool is_schema_db(const char *name)
+{
+  return !my_strcasecmp(system_charset_info,
+                        INFORMATION_SCHEMA_NAME.str, name);
+}
+
 /* sql_prepare.cc */
 
 void mysqld_stmt_prepare(THD *thd, const char *packet, uint packet_length);

sql/repl_failsafe.cc

@@ -905,7 +905,7 @@ bool load_master_data(THD* thd)
       if (!rpl_filter->db_ok(db) || 
 	  !rpl_filter->db_ok_with_wild_table(db) || 
 	  !strcmp(db,"mysql") ||
-          is_schema_db(db, strlen(db)))
+          is_schema_db(db))
       {
 	*cur_table_res = 0;
 	continue;

sql/sql_db.cc

@@ -618,7 +618,7 @@ int mysql_create_db(THD *thd, char *db, HA_CREATE_INFO *create_info,
   DBUG_ENTER("mysql_create_db");
 
   /* do not create 'information_schema' db */
-  if (is_schema_db(db, strlen(db)))
+  if (is_schema_db(db))
   {
     my_error(ER_DB_CREATE_EXISTS, MYF(0), db);
     DBUG_RETURN(-1);

sql/sql_parse.cc

@@ -2852,7 +2852,7 @@ end_with_restore_list:
 		       &first_table->grant.privilege, 0, 0,
                        test(first_table->schema_table)) ||
 	  check_access(thd,INSERT_ACL | CREATE_ACL,select_lex->db,&priv,0,0,
-                       is_schema_db(select_lex->db, strlen(select_lex->db)))||
+                       is_schema_db(select_lex->db))||
 	  check_merge_table_access(thd, first_table->db,
 				   (TABLE_LIST *)
 				   create_info.merge_list.first))
@@ -3865,7 +3865,7 @@ end_with_restore_list:
 		     first_table ? 0 : 1, 0,
                      first_table ? (bool) first_table->schema_table :
                      select_lex->db ?
-                     is_schema_db(select_lex->db, strlen(select_lex->db)) : 0))
+                     is_schema_db(select_lex->db) : 0))
       goto error;
 
     if (thd->security_ctx->user)              // If not replication
@@ -5304,7 +5304,7 @@ static bool check_show_access(THD *thd, TABLE_LIST *table)
 
     if (check_access(thd, SELECT_ACL, dst_db_name,
                      &thd->col_access, FALSE, FALSE,
-                     is_schema_db(dst_db_name, strlen(dst_db_name))))
+                     is_schema_db(dst_db_name)))
       return TRUE;
 
     if (!thd->col_access && check_grant_db(thd, dst_db_name))

sql/sql_show.cc

@@ -826,7 +826,7 @@ bool mysqld_show_create_db(THD *thd, char *dbname,
     DBUG_RETURN(TRUE);
   }
 #endif
-  if (is_schema_db(dbname, strlen(dbname)))
+  if (is_schema_db(dbname))
   {
     dbname= INFORMATION_SCHEMA_NAME.str;
     create.default_table_charset= system_charset_info;