Commit 14c4d0d7 authored by unknown's avatar unknown
Browse files

A fix for bug#4368 '"like" fails in PreparedStatement, crashes 

server': the bug occurs when arguments of LIKE function are in 
differentcharacter sets. If these character sets are compatible, 
we create an item-converter. In prepared mode, this item
needs to be created in memory of current prepared statement.


mysql-test/r/ps.result:
  Test for Bug#4368 added.
mysql-test/t/ps.test:
  A test case for bug#4368 '"like" fails in PreparedStatement, 
  crashes server'.
parent 6a5f9b41

mysql-test/r/ps.result

+11 −0
Original line number Diff line number Diff line
@@ -259,3 +259,14 @@ execute ` 
1234

1234

set names default;

create table t1 (a varchar(10)) charset=utf8;

insert into t1 (a) values ('yahoo');

set character_set_connection=latin1;

prepare stmt from 'select a from t1 where a like ?';

set @var='google';

execute stmt using @var;

a

execute stmt using @var;

a

deallocate prepare stmt;

drop table t1;

mysql-test/t/ps.test

+17 −0
Original line number Diff line number Diff line
@@ -261,3 +261,20 @@ execute ` 
set names default;





# 

# BUG#4368 "select * from t1 where a like ?" crashes server if a is in utf8

# and ? is in latin1

# Check that Item converting latin1 to utf8 (for LIKE function) is created

# in memory of prepared statement.

#



create table t1 (a varchar(10)) charset=utf8;

insert into t1 (a) values ('yahoo');

set character_set_connection=latin1;

prepare stmt from 'select a from t1 where a like ?';

set @var='google';

execute stmt using @var;

execute stmt using @var;

deallocate prepare stmt;

drop table t1;

sql/item_cmpfunc.cc

+13 −2
Original line number Diff line number Diff line
@@ -211,9 +211,20 @@ void Item_bool_func2::fix_length_and_dec() 
      }

      else

      {

	conv= new Item_func_conv_charset(args[weak],args[strong]->collation.collation);

        THD *thd= current_thd;

        /*

          In case we're in statement prepare, create conversion item

          in its memory: it will be reused on each execute.

        */

        Item_arena *arena= thd->current_arena, backup;

        if (arena->is_stmt_prepare())

          thd->set_n_backup_item_arena(arena, &backup);

	conv= new Item_func_conv_charset(args[weak],

                                         args[strong]->collation.collation);

        if (arena->is_stmt_prepare())

          thd->restore_backup_item_arena(arena, &backup);

        conv->collation.set(args[weak]->collation.derivation);

        conv->fix_fields(current_thd, 0, &conv);

        conv->fix_fields(thd, 0, &conv);

      }

      args[weak]= conv ? conv : args[weak];

    }