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In method mysql_binlog_send, right after detecting a EOF in the
read event loop, and before deciding if we should change to a new
binlog file there is a execution window where new events can be
written to the binlog and a rotation can happen. When reaching
the test, the function will then change to a new binlog file
ignoring all the events written in this window. This will result
in events not being replicated.

Only when the binlog is detected as deactivated in the event loop
of the dump thread, can we really know that no more events
remain. For this reason, this test is now made under the log lock
in the beginning of the event loop when reading the events.

FORMAT_DESCRIPTION_LOG_EVENT::CALC_SERVER_VERSION_SPLIT

Problem: When reading a Format_description_log_event, it supposes MySQL
version is always valid and DBUG_ASSERTION is used check the version number.
However, user may give a wrong binlog offset, even give a faked binary event
which includes an invalid MySQL version. This will cause server crash.

Fix: The assertions are removed and an error will be reported if MySQL
version in Format_description_log_event is invalid.

This bug had two problems:
 P1) Reads out of bounds;
 P2) Writes out of bounds.

PROBLEM P1
----------
User_var_log_event unmarshalling from binlog was not performing range
checks when using name_len and val_len variables to walk on event
buffer.

Added range checks to User_var_log_event unmarshalling to prevent
unmarshalling errors.

PROBLEM P2
----------
User_var_log_event value was allocated on thread stack, what caused
stack frame errors when User_var_log_event value was bigger than thread
stack size.

Currently value is allocated on heap memory.

QUOTING IN REPLICATION 

Problem: Misquoting or unquoted identifiers may lead to
incorrect statements to be logged to the binary log.

Fix: we use specialized functions to append quoted identifiers in
the statements generated by the server.

An "orthographic" typo in User_var::set_deferred() was made in fixes for
bug@14275000. While editing the signature of the initial patch to remove
the only argument, the assigned value of the argument remained in the body ... 
to be successfully compiled (!) thanks to names coincidence:
the arg to User_var method and its member.

Fixed with correcting the typo.

MASTER-MASTER AND USING SET USE

Problem:
=======
In a master-master set-up, a master can show a wrong
'SHOW SLAVE STATUS' output.

Requirements:
- master-master
- log_slave_updates

This is caused when using SET user-variables and then using
it to perform writes. From then on the master that performed
the insert will have a SHOW SLAVE STATUS that is wrong and  
it will never get updated until a write happens on the other
master. On"Master A" the "exec_master_log_pos" is not
getting updated.

Analysis:
========
Slave receives a "User_var" event from the master and after
applying the event, when "log_slave_updates" option is
enabled the slave tries to write this applied event into
its own binary log. At the time of writing this event the
slave should use the "originating server-id". But in the
above case the sever always logs the  "user var events"
by using its global server-id. Due to this in a
"master-master" replication when the event comes back to the
originating server the "User_var_event" doesn't get skipped.
"User_var_events" are context based events and they always
follow with a query event which marks their end of group.
Due to the above mentioned problem with "User_var_event"
logging the "User_var_event" never gets skipped where as
its corresponding "query_event" gets skipped. Hence the
"User_var" event always waits for the next "query event"
and the "Exec_master_log_position" does not get updated
properly.

Fix:
===
`MYSQL_BIN_LOG::write' function is used to write events
into binary log. Within this function a new object for
"User_var_log_event" is created and this new object is used
to write the "User_var" event in the binlog. "User var"
event is inherited from "Log_event". This "Log_event" has
different overloaded constructors. When a "THD" object
is present "Log_event(thd,...)" constructor should be used
to initialise the objects and in the absence of a valid
"THD" object "Log_event()" minimal constructor should be
used. In the above mentioned problem always default minimal
constructor was used which is incorrect. This minimal
constructor is replaced with "Log_event(thd,...)".

Fixes for BUG11761686 left a flaw that managed to slip away from testing.
Only effective filtering branch was actually tested with a regression test
added to rpl_filter_tables_not_exist.
The reason of the failure is destuction of too early mem-root-allocated memory 
at the end of the deferred User-var's do_apply_event().

Fixed with bypassing free_root() in the deferred execution branch.
Deallocation of created in do_apply_event() items is done by the base code
through THD::cleanup_after_query() -> free_items() that the parent Query
can't miss.

Problem
========
            
SQL statements close to the size of max_allowed_packet produce binary
log events larger than max_allowed_packet.
              
The reason why this failure is occuring is because the event length is
more than the total size of the max_allowed_packet + max_event_header
length. Now since the event length exceeds this size master Dump
thread is unable to send the packet on to the slave.
                      
That can happen e.g with row-based replication in Update_rows event.
            
Fix
====
          
The problem was fixed by increasing the max_allowed_packet for the
slave's threads (IO/SQL) by increasing it to 1GB.
This is done using the new server option included which is used to
regulate the max_allowed_packet of the slave thread (IO/SQL).
This causes the large packets to be received by the slave and apply
it successfully.

BUG#11761686 insert_id event is not filtered.
  
Two issues are covered.
  
INSERT into autoincrement field which is not the first part in the composed primary key 
is unsafe by autoincrement logging design. The case is specific to MyISAM engine
because Innodb does not allow such table definition.
  
However no warnings and row-format logging in the MIXED mode was done, and
that is fixed.
  
Int-, Rand-, User-var log-events were not filtered along with their parent
query that made possible them to screw up execution context of the following
query.
  
Fixed with deferring their execution until the parent query.

******
Bug#11754117 

Post review fixes.

Normally, auto_increment value is generated for the column by
inserting either NULL or 0 into it. NO_AUTO_VALUE_ON_ZERO
suppresses this behavior for 0 so that only NULL generates
the auto_increment value. This behavior is also followed by
a slave, specifically by the SQL Thread, when applying events
in the statement format from a master. However, when applying
events in the row format, the flag was ignored thus causing
an assertion failure:
"Assertion failed: next_insert_id == 0, file .\handler.cc"

In fact, we never need to generate a auto_increment value for
the column when applying events in row format on slave. So we
don't allow it to happen by using 'MODE_NO_AUTO_VALUE_ON_ZERO'.

Refactoring: Get rid of all the sql_mode checks to rows_log_event
when applying it for avoiding problems caused by the inconsistency
of the sql_mode on slave and master as the sql_mode is not set for
Rows_log_event.

Tag or remove unused arguments and variables.

      
Suprisingly, a Slave_log_event would show up in the binary
log. This event is never used and should not appear in the
logs. As such, when the slave (or the mysqlbinlog tool) reads the
event, it will hit an invalid pointer (reference to the
descriptor event when deserializing the Slave_log_event was
purposodely set to NULL).
      
The presence of the Slave_log_event denotes a corrupted log, but
we cannot tell how the log got corrupted in the first
place. However, we can make the server cope with such events when
it reads them - in case of log corruption - and fail gracefully.
     
This patch makes the server/mysqlbinlog to report that it has
found an invalid log event when Slave_log_event is read.

DROP USER 
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENTbut, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave 
executes the log event, 'CURRENT_USER()' is expand to the user of slave 
SQL thread, but SQL thread's user name always NULL. This breaks the replication.

After this patch, session's user will be written into query log events 
if these statements call CURREN_USER() or 'ALTER EVENT' does not assign a definer.

DROP USER 
RENAME USER CURRENT_USER() ...
GRANT ... TO CURRENT_USER()
REVOKE ... FROM CURRENT_USER()
ALTER DEFINER = CURRENT_USER() EVENTbut, When these statements are binlogged, CURRENT_USER() just is binlogged
as 'CURRENT_USER()', it is not expanded to the real user name. When slave 
executes the log event, 'CURRENT_USER()' is expand to the user of slave 
SQL thread, but SQL thread's user name always NULL. This breaks the replication.

After this patch, session's user will be written into query log events 
if these statements call CURREN_USER() or 'ALTER EVENT' does not assign a definer.

MYSQL_BIN_LOG m_table_map_version member and it's associated 
functions were not used in the logic of binlogging and replication,
this patch removed all related code.

When mysqlbinlog was given the --database=X flag, it always printed
'ROLLBACK TO', but the corresponding 'SAVEPOINT' statement was not
printed. The replicated filter(replicated-do/ignore-db) and binlog
filter (binlog-do/ignore-db) has the same problem. They are solved
in this patch together.

After this patch, We always check whether the query is 'SAVEPOINT'
statement or not. Because this is a literal check, 'SAVEPOINT' and
'ROLLBACK TO' statements are also binlogged in uppercase with no
any comments.

The binlog before this patch can be handled correctly except one case
that any comments are in front of the keywords. for example:
 /* bla bla */ SAVEPOINT a;
 /* bla bla */ ROLLBACK TO a;

           for InnoDB
            
The class Field_bit_as_char stores the metadata for the
field incorrecly because bytes_in_rec and bit_len are set
to (field_length + 7 ) / 8 and 0 respectively, while
Field_bit has the correct values field_length / 8 and
field_length % 8.
            
Solved the problem by re-computing the values for the
metadata based on the field_length instead of using the
bytes_in_rec and bit_len variables.
            
To handle compatibility with old server, a table map
flag was added to indicate that the bit computation is
exact. If the flag is clear, the slave computes the
number of bytes required to store the bit field and
compares that instead, effectively allowing replication
*without conversion* from any field length that require
the same number of bytes to store.

improving comments

When replicating from 4.1 master to 5.0 slave START SLAVE UNTIL can stop too late.
The necessary in calculating of the beginning of an event the event's length
did not correspond to the master's genuine information at the event's execution time.
That piece of info was changed at the event's relay-logging due to binlog_version<4 event
conversion by IO thread.

Fixed with storing the master genuine Query_log_event size into a new status
variable at relay-logging of the event. The stored info is extacted at the event
execution and participate further to caclulate the correct start position of the event
in the until-pos stopping routine.
The new status variable's algorithm will be only active when the event comes
from the master of version < 5.0 (binlog_version < 4).

'LOAD DATA CONCURRENT [LOCAL] INFILE ...' statment only is binlogged as
'LOAD DATA [LOCAL] INFILE ...' in SBR and MBR.  As a result, if replication is on, 
queries on slaves will be blocked by the replication SQL thread.

This patch write code to write 'CONCURRENT' into the log event if 'CONCURRENT' option
is in the original statement in SBR and MBR. 

      
Backporting BUG#43789 to mysql-5.1-bugteam
                              
The replication was generating corrupted data, warning messages on Valgrind
and aborting on debug mode while replicating a "null" to "not null" field.
Specifically the unpack_row routine, was considering the slave's table
definition and trying to retrieve a field value, where there was nothing to be
retrieved, ignoring the fact that the value was defined as "null" by the master.
                              
To fix the problem, we proceed as follows:
                              
1 - If it is not STRICT sql_mode, implicit default values are used, regardless
if it is multi-row or single-row statement.
                              
2 - However, if it is STRICT mode, then a we do what follows:
                              
2.1 If it is a transactional engine, we do a rollback on the first NULL that is
to be set into a NOT NULL column and return an error.
                              
2.2 If it is a non-transactional engine and it is the first row to be inserted
with multi-row, we also return the error. Otherwise, we proceed with the
execution, use implicit default values and print out warning messages.
                        
Unfortunately, the current patch cannot mimic the behavior showed by the master
for updates on multi-tables and multi-row inserts. This happens because such
statements are unfolded in different row events. For instance, considering the
following updates and strict mode:
                        
(master)
create table t1 (a int);
create table t2 (a int not null);
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
                        
t1 would have (10) and t2 would have (0) as this would be handled as a
multi-row update. On the other hand, if we had the following updates:
                        
(master)
create table t1 (a int);
create table t2 (a int);
                        
(slave)
create table t1 (a int);
create table t2 (a int not null);
                        
(master)
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
                        
On the master t1 would have (10) and t2 would have (NULL). On
the slave, t1 would have (10) but the update on t1 would fail.

"load data" statements were written to the binlog as a mix of the original statement
and bits recreated from parse-info. This relied on implementation details and broke
with IGNORE_SPACES and versioned comments.

We now completely resynthesize the query for LOAD DATA for binlog (which among other
things normalizes them somewhat with regard to case, spaces, etc.).
We have already parsed the query properly, so we make use of that rather
than mix-and-match string literals and parsed items.
This should make us safe with regard to versioned comments, even those
spanning multiple tokens. Also no longer affected by IGNORE_SPACES.

            
mysqlbinlog --database parameter was being ignored when processing
row events. As such no event filtering would take place.
            
This patch addresses this by deploying a call to shall_skip_database
when table_map_events are handled (as these contain also the name of
the database). All other rows events referencing the table id for the
filtered map event, will also be skipped.

Make the caller of Query_log_event, Execute_load_log_event
constructors and THD::binlog_query to provide the error code
instead of having the constructors to figure out the error code.

When the thread executing a DDL was killed after finished its
execution but before writing the binlog event, the error code in
the binlog event could be set wrongly to ER_SERVER_SHUTDOWN or
ER_QUERY_INTERRUPTED.

This patch fixed the problem by ignoring the kill status when
constructing the event for DDL statements.

This patch also included the following changes in order to
provide the test case.

 1) modified mysqltest to support variable for connection command

 2) modified mysql-test-run.pl, add new variable MYSQL_SLAVE to
    run mysql client against the slave mysqld.

Backporting patch to 5.0.

                  
If secure-file-priv was set on slave, it became unable to execute
LOAD DATA INFILE statements sent from master using mixed or
statement-based replication.
                  
This patch fixes the issue by ignoring this security restriction
and checking if the files are created and read by the slave in the
--slave-load-tmpdir while executing the SQL Thread.

Adding comments to some of the high-level functions in replication.

Problem: when the server reads a log_event from file, it should read
the post-header lengths from the format_description_log_event. Some
event types which currently have post-header length 0 did not do this,
and instead had a hard-coded zero length for the post-header. That
means the current server version will not be able to read future
versions of these events.
Fix: make the reader functions read the post-header.

Problem: When an Incident_log_event contains a bad incident number on disk,
the server crashes with an assertion.
Fix: Don't validate input with assertions. Use errors.

Rotate event is automatically generated and written when rotating binary
log or relay log. Rotate events for relay logs are usually ignored by slave
SQL thread becuase they have the same server id as that of the slave.
However, if --replicate-same-server-id is enabled, rotate event
for relay log would be treated as if it's a rotate event from master, and
would be executed by slave to update the rli->group_master_log_name and
rli->group_master_log_pos to a wrong value and cause the MASTER_POS_WAIT
function to fail and return NULL.

This patch fixed this problem by setting a flag bit (LOG_EVENT_RELAY_LOG_F)
in the event to tell the SQL thread to ignore these Rotate events generated
for relay logs.

This patch also added another binlog event flag bit (LOG_EVENT_ARTIFICIAL_F)
to distinquish faked events, the method used before this was by checking if
log_pos was zero.

- Implementing --base64-format=decode-rows, to display
  SQL-alike decoded row events without their BINLOG statements.
- Adding --base64-format=decode-rows into tests when
  calling mysqlbinlog to avoid non-deterministic results
- Removing resetting of last_table_id in "RESET MASTER",
  which appeared to be dangerous.

Implementing -v command line parameter to mysqlbinlog
to decode and print row events.

mysql-test/include/mysqlbinlog_row_engine.inc
mysql-test/r/mysqlbinlog_row.result
mysql-test/r/mysqlbinlog_row_big.result
mysql-test/r/mysqlbinlog_row_innodb.result
mysql-test/r/mysqlbinlog_row_myisam.result
mysql-test/r/mysqlbinlog_row_trans.result
mysql-test/t/mysqlbinlog_row.test
mysql-test/t/mysqlbinlog_row_big.test
mysql-test/t/mysqlbinlog_row_innodb.test
mysql-test/t/mysqlbinlog_row_myisam.test
mysql-test/t/mysqlbinlog_row_trans.test
  Adding tests 

client/Makefile.am
  Adding new files to symlink
  
client/mysqlbinlog.cc
  Adding -v option

sql/log_event.cc
  Impelentations of the new methods

sql/log_event.h
  Declaration of the new methods and member

sql/mysql_priv.h
  Adding new function prototype

sql/rpl_tblmap.cc
  Adding pre-processor conditions 

sql/rpl_tblmap.h
  Adding pre-processor conditions 

sql/rpl_utility.h
  Adding pre-processor conditions 

sql/sql_base.cc
  Adding reset_table_id_sequence() function.

sql/sql_repl.cc
  Resetting table_id on "RESET MASTER"
  
.bzrignore
  Ignoring new symlinked files

The problem of this bug is that we need to get the list of tables
to be updated for a multi-table update statement, which requires to
open all the tables referenced by the statement and resolve all
the fields involved in update in order to figure out the list of
tables for update. However if there are replicate filter rules,
some tables might not exist on slave and result in a failure
before we could examine the filter rules.

I think the whole problem can not be solved on slave alone,
the master must record and send the information of tables
involved for update to slave, so that the slave do not need to
open all the tables referenced by the multi-table update statement to
figure out which tables are involved for update.

So a status variable is added to Query_log event to store the
value of table map for update on master. And on slave, it will
try to get the value of this variable and use it to examine
filter rules without opening any tables on slave, if this values
is not available, the old approach is used and thus the bug will
still occur for when replicating from old masters.

The bug allow multiple executing transactions working with non-transactional
to interfere with each others by interleaving the events of different trans-
actions.

Bug is fixed by writing non-transactional events to the transaction cache and
flushing the cache to the binary log at statement commit. To mimic the behavior
of normal statement-based replication, we flush the transaction cache in row-
based mode when there is no committed statements in the transaction cache,
which means we are committing the first one. This means that it will be written
to the binary log as a "mini-transaction" with just the rows for the statement.

Note that the changes here does not take effect when building the server with
HAVE_TRANSACTIONS set to false, but it is not clear if this was possible before
this patch either.

For row-based logging, we also have that when AUTOCOMMIT=1, the code now always
generates a BEGIN/COMMIT pair for single statements, or BEGIN/ROLLBACK pair in the
case of non-transactional changes in a statement that was rolled back. Note that
for the case where changes to a non-transactional table causes a rollback due
to error, the statement will now be logged with a BEGIN/ROLLBACK pair, even
though some changes has been committed to the non-transactional table.

Problem: in mixed and statement mode, a query that refers to a
system variable will use the slave's value when replayed on
slave. So if the value of a system variable is inserted into a
table, the slave will differ from the master.
Fix: mark statements that refer to a system variable as "unsafe",
meaning they will be replicated by row in mixed mode and produce a warning
in statement mode. There are some exceptions: some variables are actually
replicated. Those should *not* be marked as unsafe.
BUG#34732: mysqlbinlog does not print default values for auto_increment variables
Problem: mysqlbinlog does not print default values for some variables,
including auto_increment_increment and others. So if a client executing
the output of mysqlbinlog has different default values, replication will
be wrong.
Fix: Always print default values for all variables that are replicated.
I need to fix the two bugs at the same time, because the test cases would
fail if I only fixed one of them.

Minor update with corrections and notes on the binlog format.
This only affects comments, not code.