for --list_files in mysqltest.

Problem: When GET_FORMAT() is called two times from the upper
level function (e.g. LEAST in the bug report), on the second
call "res= args[0]->val_str(...)" and str point to the same
String object.

1. Fix: changing the order from
- get val_str into tmp_value then convert to str
to
- get val_str into str then convert to tmp_value

The new order is more correct: the purpose of "str" parameter
is exactly to call val_str() for arguments.
The purpose of String class members (like tmp_value) is to do further
actions on the result.
Doing it in the other way around give unexpected surprises.

2. Using str_value instead of str to do padding, for the same reason.

Bug#57820 extractvalue crashes

Problem: ExtractValue and Replace crashed in some cases
due to invalid handling of empty and NULL arguments.

Per file comments:

  @mysql-test/r/ctype_ujis.result
  @mysql-test/r/xml.result
  @mysql-test/t/ctype_ujis.test
  @mysql-test/t/xml.test
  Adding tests

  @sql/item_strfunc.cc
  Make sure Item_func_replace::val_str safely handles empty strings.

  @sql/item_xmlfunc.cc
  set null_value if nodeset_func returned NULL,
  which is possible when the second argument is an
  unset user variable.

backport from 5.1

Problem: a flaw (derefencing a NULL pointer) in the LIKE optimization
code may lead to a server crash in some rare cases.

Fix: check the pointer before its dereferencing.

Lines below which were added in the patch for Bug#56814 cause this crash:

+      if (table->table)
+        table->table->maybe_null= FALSE;

Consider following test case:
--
CREATE TABLE t1(f1 INT NOT NULL);
INSERT INTO t1 VALUES (16777214),(0);

SELECT COUNT(*) FROM t1 LEFT JOIN t1 t2
ON 1 WHERE t2.f1 > 1 GROUP BY t2.f1;

DROP TABLE t1;
--

We set TABLE::maybe_null to FALSE for t2 table
and in create_tmp_field() we create appropriate tmp table field
using create_tmp_field_from_item() function instead of
create_tmp_field_from_field. As a result we have
LONGLONG field. As we have GROUP BY clause we calculate
group buffer length, see calc_group_buffer().
Item from group list which is used for calculation
refer to the field from real tables and have LONG type.
So group buffer length become insufficient for storing of
LONGLONG value. It leads to overwriting of wrong memory
area in do_field_int() function which is called from
end_update().
After some investigation I found out that
create_tmp_field_from_item() is used only for OLAP
grouping and can not be used for common grouping
as it could be an incompatibility between tmp
table fields and group buffer length.
We can not remove create_tmp_field_from_item() call from
create_tmp_field as OLAP needs it and we can not use this
function for common grouping. So we should remove setting
TABLE::maybe_null to FALSE from simplify_joins().
In this case we'll get wrong behaviour of
list_contains_unique_index() back. To fix it we
could use Field::real_maybe_null() check instead of
Field::maybe_null() and add addition check of
TABLE_LIST::outer_join.

The problem is caused by bug49487 fix and became visible
after after bug56679 fix.
Items are cleaned up and set to unfixed state after filling derived table.
So we can not rely on item::fixed state in Item_func_group_concat::print
and we can not use 'args' array as items there may be cleaned up.
The fix is always to use orig_args array of items as it
always should contain the correct data.

On Windows, the parameter for number of bytes passed into WriteFile()
and ReadFile() is DWORD. Casting is needed to silence the warning on
64-bit Windows.

Also, adding several asserts to ensure the variable for number of bytes
is no more than 32 bits, even on 64-bit Windows.

This is for InnoDB Plugin.

rb://415
Approved by: Inaam

On Windows, the parameter for number of bytes passed into WriteFile()
and ReadFile() is DWORD. Casting is needed to silence the warning on
64-bit Windows.

Also, adding several asserts to ensure the variable for number of bytes
is no more than 32 bits, even on 64-bit Windows.

This is for built-in InnoDB.

rb://415
Approved by: Inaam

The problem is dividing by const value when
the result is out of supported range.
The fix:
-return LONGLONG_MIN if the result is out of supported range for DIV operator.
-return 0 if divisor is -1 for MOD operator.

rb://498

Fix handling of update_undo_logs at trx commit. Previously, when
rseg->update_undo_list grows beyond 500 the update_undo_logs were
marked with state TRX_UNDO_TO_FREE which should have been
TRX_UNDO_TO_PURGE.

Approved by: Sunny Bains

Approved by Sunny Bains

Approved by Sunny Bains

"Grantor" columns' data is lost when replicating mysql.tables_priv.
Slave SQL thread used its default user ''@'' as the grantor of GRANT|REVOKE
statements executing on it.

In this patch, current user is put in query log event for all GRANT and REVOKE
statement, SQL thread uses the user in query log event as grantor.

  Simplified cases where a select was used to compare variable against ''

Rows events were applied wrongly on the temporary table with the same name.
But rows events are generated only for base tables. As temporary
table's data never be binlogged on row mode. Normally, base table of the
same name cannot be updated if a temporary table has the same name.
But there are two cases which can generate rows events on 
the base table of same name.
      
Case1: 'CREATE TABLE ... SELECT' statement.
In mixed format, it will generate rows events if it is unsafe.
      
Case2: Drop a transactional temporary table in a transaction
       (happens only on 5.5+).
BEGIN;
DROP TEMPORARY TABLE t1;       # t1 is a InnoDB table
INSERT INTO t1 VALUES(rand()); # t1 is a MyISAM table
COMMIT;
'DROP TEMPORARY TABLE' will be put in the transaction cache and
binlogged after the rows events generated by the 'INSERT' statement.
      
After this patch, slave opens only base table when applying a rows event.

index or foreign key

Approved by Sunny Bains

or foreign key

Fix approved by Sunny Bains

Fix assorted warnings that are generated in optimized builds.
Most of it is silencing variables that are set but unused.

This patch also introduces the MY_ASSERT_UNREACHABLE macro
which helps the compiler to deduce that a certain piece of
code is unreachable.

Fix assorted compiler warnings.

Limited to actual bug fix, fixing a while condition
Again confirmed on Linux PPC and on AIX 5.3

Tag or remove unused arguments and variables.