log-slave-updates and circul repl

Slave SQL thread may execute one extra event when there are events
skipped by slave I/O thread (e.g. originated by the same server).
Whereas it was requested not to do so by the UNTIL condition.

This happens because we compare with the end position of previously
executed event. This is fine when there are no skipped by slave I/O
thread events, as end position of previous event equals to start
position of to be executed event. Otherwise this position equals to
start position of skipped event.

This is fixed by:
- reading the event to be executed before checking if the until condition
  is satisfied.
- comparing the start position of the event to be executed. Since we do
  not have the start position available, we compute it by subtracting
  event length from end position (which is available).
- if there are no events on the event queue at the slave sql starting
  time, that meet until condition, we stop immediately, as in this
  case we do not want to wait for next event.

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  stella.local:/home2/mydev/mysql-5.0-axmrg

            from storage engine

Federated may crash a server, return wrong result set, return
"ERROR 1030 (HY000): Got error 1430 from storage engine" message
when local (engine=federated) table has a key against nullable
column.

The problem was wrong implementation of function that creates
WHERE clause for remote query from key.

empty result when using DESC

Problem: fetching MyISAM keys we copy a key block pointer to the end of the key buffer.
However, we don't take into account the pointer length calculatig the buffer size,
that may leads to memory overwriting and in turn to unpredictable results.

Fix: increase key buffer size by length of the key block pointer.

Note: no simple test case.

into  dl145h.mysql.com:/data0/mkindahl/mysql-5.0-rpl-merge

into  stella.local:/home2/mydev/mysql-5.0-axmrg

into  dl145h.mysql.com:/data0/mkindahl/mysql-5.0-rpl-merge

into  dipika.(none):/opt/local/work/mysql-5.0-runtime

The unsignedness of large integer user variables was not being
properly preserved when feeded to prepared statements. This was
happening because the unsigned flags wasn't being updated when
converting the user variable is converted to a parameter.

The solution is to copy the unsigned flag when converting the
user variable to a parameter and take the unsigned flag into
account when converting the integer to a string.

into  pilot.mysql.com:/data/msvensson/mysql/mysql-5.0-runtime

slash in filenames also for Create_file_log_event.

    to leave

The artifact was caused by
a flaw in concurrent accessing the slave's io thd by
the io itself and a handling show slave status thread.
Namely, show_master_info did not acquire mi->run_lock mutex that is
specified for mi->io_thd member.

Fixed with deploying the mutex locking and unlocking. The mutex is kept
short time and without interleaving with mi->data_lock mutex.

Todo: to report and fix an issue with 
    sys_var_slave_skip_counter::{methods} 
seem to acquire incorrectly
     active_mi->rli.run_lock
instead of the specified
     active_mi->rli.data_lock

A test case is difficult to compose, so rpl_packet should continue serving
as the indicator.

into  mysql_cab_desk.:D:/source/c++/mysql-5.0-rpl-merge

This patch adds code to convert the path for LOAD DATA INFILE 
events to a Unix path which is needed for running mysql client
on Windows. 

on the context.

into  dl145h.mysql.com:/data0/mkindahl/mysql-5.0-rpl-merge

            'Wrong parameters to functi

START SLAVE reports vague error when it fails to register on master:
"Wrong parameters to function register_slave".

If master failed to register slave because of too long
'report-host'/'report-user'/'report-password', return better error
messages:
"Failed to register slave: too long 'report-host'"
"Failed to register slave: too long 'report-user'"
"Failed to register slave; too long 'report-password'"

No test case for this fix.

into  dl145h.mysql.com:/data0/mkindahl/mysql-5.0-rpl-merge

into  mail.hezx.com:/media/sda3/work/mysql/bkwork/bug26489_corruption_in_relay_log/5.0

into  stella.local:/home2/mydev/mysql-5.0-axmrg

Here is the scenario that causes the failure.(by Mats)

1. The to-be corrupt log event (let's call it X), is split into two
   packets B and C on the network level (net_write_buff()). The parts
   are X = (x',x''). The part x' ends up in packet B and part x''
   ends up in packet C. Prior to the corrupt event X, the event Y has
   been written successfully, but has been split into two packets as
   well, which we call (y',y'').
2. The master sends packet A = (y'',x') to the slave, increases the
   packet sequence number, the slave receives the packet, but fails
   to reply before the master gets a timeout.
3. Since the master got a timeout, it reports failure, and aborts
   sending the binary log by exiting mysql_binlog_send(). However, it
   leaves the buffer intact, still holding y'' (but not x', since the
   write_pos is not increased).
4. After exiting mysql_binlog_send(), the master does a
   disconnection of the client thread, which involves sending an
   error message e to the client (i.e., the slave).
5. In this case, net_write_buff() is used again, but this time the
   old contents of the packet is used so that the new packet is
   D = (y'',e). Note that this will use a new packet sequence number,
   since the packet number was increased in step 2.
6. The slave receives the tail y'' of the Y log event, concatenates
   this with x' (which it already received), and writes the event
   (x',y'') it to the relay log since it hasn't noticed anything is
   amiss.
7. It then tries to read more bytes, which is either e (if the length
   given for X just happened to match the length given for Y, or just
   plain garbage because the slave is out of sync with what is
   actually sent.
8. After a while, the SQL thread tries to execute the event (x',y''),
   which is very likely to be just nonsense.

The problem can be fixed by not resetting net->error after the call of 
mysql_binlog_send, so the error message will not be sent and the connection
will be closed.

and so that it works correctly on Windows.

into  ramayana.hindu.god:/home/tsmith/m/bk/maint/50

The problem is when create/rename/drop users, the statement was logged regardless of error, even if no data has been changed, the statement was logged.

After this patch, create/rename/drop users don't write the binlog if the statement makes no changes, if the statement does make any changes, log the statement with possible error code.

This patch is based on the patch for BUG#29749, which is not pushed