Commit 399bf23c authored by unknown's avatar unknown
Browse files

Bug #26537: item_unhex() was not expected 

to return NULL for non-NULL arguments.
This is not the case as it can return NULL
for invalid hexidecimal strings.
Fixed by setting the maybe_null flag.


mysql-test/r/func_str.result:
  Bug #26537: test case
mysql-test/t/func_str.test:
  Bug #26537: test case
sql/item_strfunc.h:
  Bug #26537: item_unhex() can return NULLs
  even for guaranteed non-null arguments.
parent 3a520a78

mysql-test/r/func_str.result

+6 −0
Original line number Diff line number Diff line
@@ -1940,4 +1940,10 @@ abcxx 
select lpad('abc', cast(5 as unsigned integer), 'x');

lpad('abc', cast(5 as unsigned integer), 'x')

xxabc

SELECT UNHEX('G');

UNHEX('G')

NULL

SELECT UNHEX('G') IS NULL;

UNHEX('G') IS NULL

1

End of 5.0 tests

mysql-test/t/func_str.test

+6 −0
Original line number Diff line number Diff line
@@ -1008,4 +1008,10 @@ select repeat('a', cast(2 as unsigned int)); 
select rpad('abc', cast(5 as unsigned integer), 'x');

select lpad('abc', cast(5 as unsigned integer), 'x');



#

# Bug #26537: UNHEX() IS NULL comparison fails

#

SELECT UNHEX('G');

SELECT UNHEX('G') IS NULL;



--echo End of 5.0 tests

sql/item_strfunc.h

+5 −1
Original line number Diff line number Diff line
@@ -605,7 +605,11 @@ class Item_func_unhex :public Item_str_func 
{

  String tmp_value;

public:

  Item_func_unhex(Item *a) :Item_str_func(a) {}

  Item_func_unhex(Item *a) :Item_str_func(a) 

  { 

    /* there can be bad hex strings */

    maybe_null= 1; 

  }

  const char *func_name() const { return "unhex"; }

  String *val_str(String *);

  void fix_length_and_dec()