Bug#17075846 - UNQUOTED FILE NAMES FOR VARIABLE VALUES ARE

	       ACCEPTED BUT PARSED INCORRECTLY

When we are setting the value in a system variable, 
We can set it like 

set sys_var="Iden1.Iden2";		//1
set sys_var='Iden1.Iden2';		//2
set sys_var=Iden1.Iden2;		//3
set sys_var=.ident1.ident2; 		//4
set sys_var=`Iden1.Iden2`;		//5


While parsing, for case 1(when ANSI_QUOTES is enable) and 2,
we will take as string literal(we will make item of type Item_string).
for case 3 & 4, taken as Item_field, where Iden1 is a table name and
iden2 is a field name.
for case 5, again Item_field type, where iden1.iden2 is taken as
field name.


Now in case 1, when we are assigning some value to system variable
(which can take string or enumerate type data), we are setting only 
field part.
This means only iden2 value will be set for system variable. This 
result in wrong result.

Solution:

(for string type) We need to Document that we are not allowed to set 
system variable which takes string as identifier, otherwise result 
in unexpected behaviour.

(for enumerate type)
if we pass iden1.iden2, we will give an error ER_WRONG_TYPE_FOR_VAR
(Incorrect argument type to variable).

mysql-test/r/parser.result

@@ -622,3 +622,28 @@ DROP TABLE t1, t2, t3;
 #
 # End of 5.1 tests
 #
+#
+# Bug#17075846 : unquoted file names for variable values are
+#                accepted but parsed incorrectly
+#
+SET default_storage_engine=a.myisam;
+ERROR 42000: Incorrect argument type to variable 'default_storage_engine'
+SET default_storage_engine = .a.MyISAM;
+ERROR 42000: Incorrect argument type to variable 'default_storage_engine'
+SET default_storage_engine = a.b.MyISAM;
+ERROR 42000: Incorrect argument type to variable 'default_storage_engine'
+SET default_storage_engine = `a`.MyISAM;
+ERROR 42000: Incorrect argument type to variable 'default_storage_engine'
+SET default_storage_engine = `a`.`MyISAM`;
+ERROR 42000: Incorrect argument type to variable 'default_storage_engine'
+set default_storage_engine = "a.MYISAM";
+ERROR 42000: Unknown storage engine 'a.MYISAM'
+set default_storage_engine = 'a.MYISAM';
+ERROR 42000: Unknown storage engine 'a.MYISAM'
+set default_storage_engine = `a.MYISAM`;
+ERROR 42000: Unknown storage engine 'a.MYISAM'
+CREATE TABLE t1 (s VARCHAR(100));
+CREATE TRIGGER trigger1 BEFORE INSERT ON t1 FOR EACH ROW
+SET default_storage_engine = NEW.INNODB;
+ERROR 42S22: Unknown column 'INNODB' in 'NEW'
+DROP TABLE t1;

mysql-test/suite/sys_vars/r/general_log_file_basic.result

@@ -10,6 +10,7 @@ RIGHT(@@global.general_log_file, length(@a)) = @a
 1
 '#--------------------FN_DYNVARS_004_02------------------------#'
 SET @@global.general_log_file = mytest.log;
+ERROR 42000: Incorrect argument type to variable 'general_log_file'
 SET @@global.general_log_file = 12;
 ERROR 42000: Incorrect argument type to variable 'general_log_file'
 '#----------------------FN_DYNVARS_004_03------------------------#'

mysql-test/suite/sys_vars/r/slow_query_log_file_basic.result

@@ -7,6 +7,7 @@ RIGHT(@@global.slow_query_log_file, length(@a)) = @a
 1
 '#--------------------FN_DYNVARS_004_02------------------------#'
 SET @@global.slow_query_log_file = mytest.log;
+ERROR 42000: Incorrect argument type to variable 'slow_query_log_file'
 SET @@global.slow_query_log_file = 12;
 ERROR 42000: Incorrect argument type to variable 'slow_query_log_file'
 '#----------------------FN_DYNVARS_004_03------------------------#'

mysql-test/suite/sys_vars/t/general_log_file_basic.test

@@ -54,7 +54,7 @@ SELECT RIGHT(@@global.general_log_file, length(@a)) = @a;
 #        Change the value of general_log_file to a invalid value      #
 #######################################################################
 
-# Assumed text if no quotes or numbers.
+--error ER_WRONG_TYPE_FOR_VAR
 SET @@global.general_log_file = mytest.log;
 --error ER_WRONG_TYPE_FOR_VAR
 SET @@global.general_log_file = 12;

mysql-test/suite/sys_vars/t/slow_query_log_file_basic.test

@@ -52,7 +52,7 @@ SELECT RIGHT(@@global.slow_query_log_file, length(@a)) = @a;
 #      Change the value of slow_query_log_file to a invalid value     #
 #######################################################################
 
-# Assumed text if no quotes or numbers.
+--error ER_WRONG_TYPE_FOR_VAR
 SET @@global.slow_query_log_file = mytest.log;
 --error ER_WRONG_TYPE_FOR_VAR
 SET @@global.slow_query_log_file = 12;

mysql-test/t/parser.test

@@ -733,3 +733,28 @@ DROP TABLE t1, t2, t3;
 --echo # End of 5.1 tests
 --echo #
 
+--echo #
+--echo # Bug#17075846 : unquoted file names for variable values are
+--echo #                accepted but parsed incorrectly
+--echo #
+--error ER_WRONG_TYPE_FOR_VAR 
+SET default_storage_engine=a.myisam;
+--error ER_WRONG_TYPE_FOR_VAR 
+SET default_storage_engine = .a.MyISAM;
+--error ER_WRONG_TYPE_FOR_VAR 
+SET default_storage_engine = a.b.MyISAM;
+--error ER_WRONG_TYPE_FOR_VAR 
+SET default_storage_engine = `a`.MyISAM;
+--error ER_WRONG_TYPE_FOR_VAR 
+SET default_storage_engine = `a`.`MyISAM`; 
+--error ER_UNKNOWN_STORAGE_ENGINE 
+set default_storage_engine = "a.MYISAM";
+--error ER_UNKNOWN_STORAGE_ENGINE 
+set default_storage_engine = 'a.MYISAM';
+--error ER_UNKNOWN_STORAGE_ENGINE 
+set default_storage_engine = `a.MYISAM`;
+CREATE TABLE t1 (s VARCHAR(100));
+--ERROR ER_BAD_FIELD_ERROR
+CREATE TRIGGER trigger1 BEFORE INSERT ON t1 FOR EACH ROW
+SET default_storage_engine = NEW.INNODB;
+DROP TABLE t1;

sql/sql_yacc.yy

 /*
-   Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -444,6 +444,13 @@ set_system_variable(THD *thd, struct sys_var_with_base *tmp,
   if (lex->spcont && tmp->var == Sys_autocommit_ptr)
     lex->sphead->m_flags|= sp_head::HAS_SET_AUTOCOMMIT_STMT;
 
+  if (val && val->type() == Item::FIELD_ITEM &&
+      ((Item_field*)val)->table_name)
+  {
+    my_error(ER_WRONG_TYPE_FOR_VAR, MYF(0), tmp->var->name.str);
+    return TRUE;
+  }
+
   if (! (var= new set_var(var_type, tmp->var, &tmp->base_name, val)))
     return TRUE;