Backport from mysql-5.5 to mysql-5.1

Bug#19880368 : GROUP_CONCAT CRASHES AFTER DUMP_LEAF_KEY

Problem:
find_order_by_list does not update the address of order_item
correctly after resolving.

Solution:
Change the ref_by address for a order_by field if its
SUM_FUNC_ITEM to the address of the field present in
all_fields.

Backport from mysql-5.5 to mysql-5.1

Bug #19612819 :  FILESORT: ASSERTION FAILED: POS->FIELD != 0 || POS->ITEM != 0

Problem:
While getting the temp table field for a REF_ITEM
make_sortorder is using the real_item. As a result
server fails later with an assert.

Solution:
Do not use real_item to get the temp table field.
Instead use the REF_ITEM itself as temp table fields
are created for REF_ITEM not the real_item.

               MYISAM TABLE CAUSES THE SERVER TO CRASH

Issue:
-----
During index maintanence, R-tree node might need a split.
In some cases the square of mbr could be calculated to
infinite (as in this case) or to NaN. This is currently
not handled. This is specific to MyISAM.

SOLUTION:
---------
If the calculated value in "mbr_join_square" is infinite or
NaN, set it to max double value.

Initialization of output parameters of "pick_seeds" is
required if calculation is infinite (or negative infinite).

Similar to the fix made for INNODB as part of Bug#19533996.

Conflicts:
	mysql-test/suite/sys_vars/r/transaction_alloc_block_size_basic.result
	mysql-test/suite/sys_vars/r/transaction_prealloc_size_basic.result
	mysql-test/suite/sys_vars/t/transaction_alloc_block_size_basic.test
	mysql-test/suite/sys_vars/t/transaction_prealloc_size_basic.test
	sql/mysqld.cc

Backport from mysql-5.5 to mysql-5.1 of:

Bug19770858: MYSQLD CAN BE DRIVEN TO OOM WITH TWO SIMPLE SESSION VARS

The problem was that the maximum value of the transaction_prealloc_size
session system variable was ULONG_MAX which meant that it was possible
to cause the server to allocate excessive amounts of memory.

This patch fixes the problem by reducing the maxmimum value of
transaction_prealloc_size and transaction_alloc_block_size down
to 128K.

Note that transactions will still be able to allocate more than
128K if needed, this patch just reduces the amount that can be
preallocated - as well as the maximum size of the incremental
allocation blocks.

(cherry picked from commit 540c9f7ebb428bbf9ec028feabe1f7f919fdefd9)

Conflicts:
	mysql-test/suite/sys_vars/r/transaction_alloc_block_size_basic.result
	mysql-test/suite/sys_vars/r/transaction_alloc_block_size_basic_64.result
	mysql-test/suite/sys_vars/t/disabled.def
	mysql-test/suite/sys_vars/t/transaction_alloc_block_size_basic.test
	sql/sys_vars.cc

BINLOGGED INCORRECTLY - BREAKS A SLAVE

Submitted a incomplete patch with my previous push,
re submitting the extra changes the required to make
the patch complete.

Analysis:
In row based replication, Master does not send temp table information
to Slave. If there are any DDLs that involves in regular table that needs
to be sent to Slave and a temp tables (which will not be available at Slave),
the Master rewrites the query replacing temp table with it's defintion.
Eg: create table regular_table like temptable.
In rewrite logic, server is ignoring the database of regular table
which can cause problems mentioned in this bug.

Fix: dont ignore database information (if available) while
rewriting the query

This reverts commit c7de768ec20f5167cff2c69a255d95ca2eded46a.

			RESERVATION AND SIGNAL COUNT

Problem:
	Reservation and Signal count value shows negative value for show engine
innodb statement.

Solution:
	This is happening due to counter overflow error. Reservation and Signal
count values are defined as unsigned long but these variables are converted to
long while printing it. Change Reservation and Signal count values as unsigned
long datatype while printing it.
Reviewed-by: Marko Mäkelä <marko.makela@oracle.com>
Approved in bug page.

               MYISAM TABLE CAUSES THE SERVER TO CRASH

Issue:
-----
During index maintanence, R-tree node might need a split.
In some cases the square of mbr could be calculated to
infinite (as in this case) or to NaN. This is currently
not handled. This is specific to MyISAM.

SOLUTION:
---------
If the calculated value in "mbr_join_square" is infinite or
NaN, set it to max double value.

Initialization of output parameters of "pick_seeds" is
required if calculation is infinite (or negative infinite).

Similar to the fix made for INNODB as part of Bug#19533996.

Problem:

This is a coding mistake during error handling.  When the specified foreign
key constraint is wrong because of data type mismatch, the resulting
foreign key object will not have valid foreign->id (it will be NULL.)

Solution:

While removing the foreign key object from dictionary cache during error
handling, ensure that foreign->id is not null before using it.

rb#8204 approved by Sunny.

Log file directory had too strict access rights, server not able
to write to log file.
Signed-off-by: Terje Røsten <terje.rosten@oracle.com>

Due to large version numbers used libmysqlclient-devel packages was
not considered for install. Fixed by removing version check.

		3RD EXECUTION OF PS

Problem:
When order by is by a column number for a group concat function
which has an outer reference, server fails in case of prepared
statements on the third execution

Analysis:
When a group concat function has order by, the fields in order by
are not resolved until execution if the input is a column number.
During execution they get resolved after the temp table gets created.
As a result they will be pointing to temp table fields which are
runtime created objects. This results in dangling pointers leading
to server failure.

Solution:
Reset the pointers for the order by fields to point to the original
arguments after execution as they are invalid.
Done in Item_func_group_concat::cleanup.

ISSUE:
------
There can be up to MERGEBUFF2 number of sorted merge chunks,
We need enough buffer space for at least one record from
each merge chunks. If estimates are wrong(very low) and we
allocate buffer space for less than MERGEBUFF2, then we will
have issue in merge_buffers, if actual number of rows to be
sorted is bigger than estimate and external filesort is
chosen.

SOLUTION:
---------
Set number of rows to sort to be at least MERGEBUFF2.

Problem:
find_order_by_list does not update the address of order_item
correctly after resolving.

Solution:
Change the ref_by address for a order_by field if its
SUM_FUNC_ITEM to the address of the field present in
all_fields.

Problem:
While getting the temp table field for a REF_ITEM
make_sortorder is using the real_item. As a result
server fails later with an assert.

Solution:
Do not use real_item to get the temp table field.
Instead use the REF_ITEM itself as temp table fields
are created for REF_ITEM not the real_item.

In versions 5.5 and 5.6 the MySQL version is not logged until
server is started and ready to accept connections. Exiting
server before this point will not have server version information
in the log. But in 5.7 code, we log a server version information
just after we prepare server_version string and logging is initialized.

For 5.5 and 5.6 code also adding this code to print server version
information.

Test results:
================

5.5
-----
Server version will be logged as below on server startup:
141218  8:45:48 [Note] /home/praveen/WorkDir/mysql_local/bug20052694/mysql/sql/mysqld (mysqld 5.5.42-debug-log) starting as process 19697 ...

5.6
----
Server version will be logged as below on server startup:
2014-12-18 09:08:43 0 [Note] /home/praveen/WorkDir/mysql_local/bug20052694/mysql-5.6/sql/mysqld (mysqld 5.6.23-debug-log) starting as process 18474 ...

LEADS TO INCORRECT BEHAVIOR

ISSUE:
------
When the following conditions are satisfied in a query, a
server crash occurs:
a) Two rows are compared using a NULL-safe equal-to operator.
b) Each of these rows belong to different charsets.

SOLUTION:
---------
When one charset is converted to another for comparision,
the constructor of "Item_func_conv_charset" is called.
This will attempt to use the Item_cache if the string is a
constant. This check succeeds because the "used_table_map"
of the Item_cache class is never set to the correct value.
Since it is mistakenly assumed to be a constant, it tries
to fetch the relevant null value related fields which are
yet to be initialized. This results in valgrind issues
and wrong results.

The fix is to update the "used_table_map" of "Item_cache".
This will allow "Item_func_conv_charset" to realise that
this is not a constant.

ISSUE:
------
We pre-allocate the ref_pointer_array before we resolve outer
references. This means that in some cases the
ref_pointer_array may not be large enough to hold all
references created. One such case is aggregate functions in
having clause of a subquery which may add items to select list
of outer query. So it is necessary to consider
select_n_having_items for subqueries while allocating
ref_pointer_array else we will get buffer overflow.

SOLUTION:
---------
Allocate a larger ref_pointer_array by aggregating
select_n_having_items for subqueries.
The fix in sql_yacc.yy is a backport from bug fix 18782905.

              CRASHES WITH AUTO_INCREMENT COLUMN

Description:- Creating a federated table with AUTO_INCREMENT
column using LIKE clause results in a server crash.

Analysis:- Creating a federated table with AUTO_INCREMENT
column using LIKE clause results in a federated server
crash due to the uninitialized connection structure(mysql).
Also due to unassigned connection string for the remote
server, at the time of preparation of "create_info"
structure, the creation of any federated table using LIKE
clause fails with an error, "ERROR 1 (HY000): server name:
'' doesn't exist!". This  bug is not only with
AUTO_INCREMENT but in all creations of federated tables with
LIKE clause.

Fix :- In ha_federated::info(), "mysql->insert_id" assigned
to "stats.auto_increment_value" only when there is an
active connection. This fixes the crash issue. For creating
the federated table with LIKE clause, connection string is
assigned at the time of preparation of "create_info"
structure.

Backporting the patch and the test case fixed as part
of BUG#16041903 and BUG#19683834 respectively.

The problem was that the maximum value of the transaction_prealloc_size
session system variable was ULONG_MAX which meant that it was possible
to cause the server to allocate excessive amounts of memory.

This patch fixes the problem by reducing the maxmimum value of
transaction_prealloc_size and transaction_alloc_block_size down
to 128K.

Note that transactions will still be able to allocate more than
128K if needed, this patch just reduces the amount that can be
preallocated - as well as the maximum size of the incremental
allocation blocks.

Fixing a post push test issue.

Problem Description And Fix:
Inserting a fudged record in mysql.proc with the dbname
column value as test and the name column as empty, will
cause a crash in mysqld when we run the command DROP
DATABASE test.
 During DROP DATABASE test, mysql_rm_db subsequently
calls lock_db_routines. In the routine we fetch the
field 'name' from mysql.proc by calling the underlying
storage engine API in lock_db_routines. This cause NULL
value as the field column of mysql.proc and subsequent
dereference MDL_request::init leads to crash.
Modifying mysql.proc using SQL command by user is not
supported, but in principle, there is a possibility
of mysql.proc getting corrupted which can also lead
to empty fields and arbitary values. The patch fixes
the crash by checking NULL and propagating the appopriate
error code to the user.

Rename a CMake variable in compile_flags.cmake to avoid triggering
CMake 3.1 warning about CMP0054 about interpreting if() arguments
as keywords or variables.

No changes in behavior.

special character sets like utf16, utf32, ucs2.

Analysis: MySQL server does not support few special character sets like
  utf16,utf32 and ucs2 as "client's character set"(eg: utf16,utf32, ucs2).
  It is known limitation listed in the documentation
  http://dev.mysql.com/doc/refman/5.5/en/charset-connection.html.

  The default value for default-character-set parameter is 'auto'
  which means that if the server's character set is not supported,
  then server automatically changes client's character set to
  predefined character-set which is 'latin1' in the current code.

  Eg:
  $ ./mysql -uroot -S$SOCKET_FILE --default-character-set=utf16
  ERROR 1231 (42000): Variable 'character_set_client' can't be set to the value of 'utf16'

  $ ./mysql -uroot -S$SOCKET_FILE will be successfully connected to
  server with 'latin1' as default client side character set.

  When IO thread is trying to connect to Master, it sets server's character
  set as client's character set. When Slave server is started with these
  special character sets, IO thread (which is like a connection to Master)
  fails because of the above said limitation.

 Fix: Now even IO thread also behaves the same as a regular client behaves.
  i.e., If server's character set is not supported as client's character set,
  then set default's client character set(latin1) as client's character set.

Attempt to truncate temporary table using Blackhole storage and
locked by LOCK TABLES caused assertion failure and crashes.

Blackhole is a transaction-aware engine. While creating the temporary
table in transaction-aware engine, temporary table of type
"TRANSACTIONAL_TMP_TABLE" is created. For such temporary tables
a THR_LOCK lock is acquired by the LOCK TABLE operation. References
to them are also added into MYSQL_LOCK::table[] array. Also for
Blackhole engine, flag HTON_CAN_RECREATE is set.

While truncating temporary tables, no locks are taken and
recreate_temporary_table() is called for engines having
"HTON_CAN_RECREATE" in flag.

Function closefrm() is called from the recreate_temporary_table(),
to close the current temporary table. In closefrm(), the lock on
table expected is "F_UNLCK". In debug builds, assert condition on
this fails when lock of type "F_WRLCK" is acquired by LOCK TABLE
operation on temporary tables using Blackhole engine.

In non-debug builds closefrm() simply freed TABLE object leaving
dangling pointer to this object in MYSQL_LOCK::table[] array which
might lead to crashes later.

Fix:
---------
To fix this issue, we now unlock and remove table from MYSQL_LOCK::table[]
array before calling close_temporary_table() in recreate_temporary_table().
This is achieved by calling mysql_lock_remove() function for this table.

Explicitly disable weaker SSL protocols.

Upgrading YaSSL from 2.3.5 to 2.3.7

Reviewed-by : Kristofer Pettersson <kristofer.pettersson@oracle.com>
Reviewed-by : Vamsikrishna Bhagi <vamsikrishna.bhagi@oracle.com>

Fix:
===
Backport Bug#11756194 to mysql-5.5. slave breaks if
'drop database' fails on master and mismatched tables on
slave.

'DROP TABLE <deleted tables>' was binlogged when
'DROP DATABASE' failed and at least one table was deleted
from the database. The log event would lead slave SQL thread
stop if some of the tables did not exist on slave.

After this patch, It is always binlogged with 'IF EXISTS'
option.

		CRASHES ON EVERY START ATTEMPT

Description:
------------
push_warning_printf function is used to print the warning message
to the client. So this function should not invoke while recovering
the server. Moreover current_thd is NULL while starting the server.

Solution:
---------
 - Avoiding the warning to be printed while recovery.
This patch already pushed in mysql-5.6.