Before BUG#28796, an empty host was used to identify that an instance was no
longer a slave. However, BUG#28796 changed this behavior and one cannot set
an empty host. Besides, a RESET SLAVE only cleans up information on the next
event to retrieve from the master, disables ssl and resets heartbeat period.
So a call to SHOW SLAVE STATUS after issuing a RESET SLAVE still returns some
valid information, such as host, port, user and password.

To fix this problem, we have introduced the command RESET SLAVE ALL that does
what a regular RESET SLAVE does and also clears host, port, user and password
information thus allowing users to identify when an instance is no longer a
slave.

Major replication test framework cleanup. This does the following:
 - Ensure that all tests clean up the replication state when they
   finish, by making check-testcase check the output of SHOW SLAVE STATUS.
   This implies:
    - Slave must not be running after test finished. This is good
      because it removes the risk for sporadic errors in subsequent
      tests when a test forgets to sync correctly.
    - Slave SQL and IO errors must be cleared when test ends. This is
      good because we will notice if a test gets an unexpected error in
      the slave threads near the end.
    - We no longer have to clean up before a test starts.
 - Ensure that all tests that wait for an error in one of the slave
   threads waits for a specific error. It is no longer possible to
   source wait_for_slave_[sql|io]_to_stop.inc when there is an error
   in one of the slave threads. This is good because:
    - If a test expects an error but there is a bug that causes
      another error to happen, or if it stops the slave thread without
      an error, then we will notice.
    - When developing tests, wait_for_*_to_[start|stop].inc will fail
      immediately if there is an error in the relevant slave thread.
      Before this patch, we had to wait for the timeout.
 - Remove duplicated and repeated code for setting up unusual replication
   topologies. Now, there is a single file that is capable of setting
   up arbitrary topologies (include/rpl_init.inc, but
   include/master-slave.inc is still available for the most common
   topology). Tests can now end with include/rpl_end.inc, which will clean
   up correctly no matter what topology is used. The topology can be
   changed with include/rpl_change_topology.inc.
 - Improved debug information when tests fail. This includes:
    - debug info is printed on all servers configured by include/rpl_init.inc
    - User can set $rpl_debug=1, which makes auxiliary replication files
      print relevant debug info.
 - Improved documentation for all auxiliary replication files. Now they
   describe purpose, usage, parameters, and side effects.
 - Many small code cleanups:
    - Made have_innodb.inc output a sensible error message.
    - Moved contents of rpl000017-slave.sh into rpl000017.test
    - Added mysqltest variables that expose the current state of
      disable_warnings/enable_warnings and friends.
    - Too many to list here: see per-file comments for details.

Some of the test cases reference to binlog position and
these position numbers are written into result explicitly.
It is difficult to maintain if log event format changes. 

There are a couple of cases explicit position number appears, 
we handle them in different ways
A. 'CHANGE MASTER ...' with MASTER_LOG_POS or/and RELAY_LOG_POS options
   Use --replace_result to mask them.
B. 'SHOW BINLOG EVENT ...'
   Replaced by show_binlog_events.inc or wait_for_binlog_event.inc. 
   show_binlog_events.inc file's function is enhanced by given
   $binlog_file and $binlog_limit.
C. 'SHOW SLAVE STATUS', 'show_slave_status.inc' and 'show_slave_status2.inc'
   For the test cases just care a few items in the result of 'SHOW SLAVE STATUS',
   only the items related to each test case are showed.
   'show_slave_status.inc' is rebuild, only the given items in $status_items
   will be showed.
   'check_slave_is_running.inc' and 'check_slave_no_error.inc'
   and 'check_slave_param.inc' are auxiliary files helping
   to show running status and error information easily.

NOTE: Backport of:

bzr log -r revid:sp1r-serg@sergbook.mysql.com-20070505200319-38337
------------------------------------------------------------
revno: 2469.263.4
committer: serg@sergbook.mysql.com
timestamp: Sat 2007-05-05 13:03:19 -0700
message:
  Removing deprecated features:
  --master-XXX command-line options
  log_bin_trust_routine_creators
  table_type
  BACKUP TABLE ...
  RESTORE TABLE ...
  SHOW PLUGIN
  LOAD TABLE ... FROM MASTER
  LOAD DATA FROM MASTER
  SHOW INNODB STATUS
  SHOW MUTEX STATUS
  SHOW TABLE TYPES
  ... TIMESTAMP(N)
  ... TYPE=engine
  
  RESET SLAVE don't reset connection parameters anymore
  LOAD DATA: check opt_secure_file_priv before access(filename)
  improved WARN_DEPRECATED macro

The test case added failed sporadically on PB. This is due to the
fact that the user thread in some cases is waiting for slave IO
to stop and then check the error number. Thence, sometimes the
user thread would race for the error number with IO thread.

This post push fix addresses this by replacing the wait for slave
io to stop with a wait for slave io error (as it seems it was
added in 6.0 also after patch on which this is based was
pushed). This implied backporting wait_for_slave_io_error.inc
from 6.0 also.

The server was not cleaning the last IO error and error number when
resetting slave.

This patch addresses this issue by backporting into 5.1 part of the
patch in BUG 34654. A fix for this issue had already been pushed into
6.0 as part of the aforementioned bug, however the patch also included
some refactoring. The fix for 5.1 does not take into account the
refactoring part.

Mask binlog positions, error, warning and other information that are not significant for the test

been reached):

Post-merge patch to handle all the changes to the tree since the tree
was cloned.

This includes both code and test cases.

   * A more dynamic binlog format which allows small changes (1064)
   * Log session variables in Query_log_event (1063)
It contains a few bugfixes (which I made when running the testsuite).
I carefully updated the results of the testsuite (i.e. I checked for every one,
if the difference between .reject and .result could be explained).
Apparently mysql-test-run --manager is broken in 4.1 and 5.0 currently,
so I could neither run the few tests which require --manager, nor check
that they pass nor modify their .result. But for builds, we don't run
with --manager.
Apart from --manager, the full testsuite passes, with Valgrind too (no errors).
I'm going to push in the next minutes. Remains: update the manual.
Note: by chance I saw that (in 4.1, in 5.0) rpl_get_lock fails when run alone;
this is normal at it makes assumptions on thread ids. I will fix this one day
in 4.1.

rli->save_temporary_tables and slave_open_temp_tables
(in old 4.0 you could make "SHOW STATUS LIKE 'slave_open_temp_tables'" grow
indefinitely by doing RESET SLAVE and replicating always the same CREATE
TEMPORARY TABLE).
It's critical to reset save_temporary_tables to 0 (otherwise you may later
read memory which has been freed) so this changeset should go into 4.1.

I manually edited rpl_openssl.result because the test is skipped on my
machine. Hope it's correct.

"Add a column "Timestamp_of_last_master_event_executed" in SHOW SLAVE STATUS".
Finally this is adding
- Slave_IO_State (a copy of the State column of SHOW PROCESSLIST for the I/O thread,
so that the users, most of the time, has enough info with only SHOW SLAVE STATUS).
- Seconds_behind_master. When the slave connects to the master it does SELECT UNIX_TIMESTAMP()
on the master, computes the absolute difference between the master's and the slave's clock.
It records the timestamp of the last event executed by the SQL thread, and does a
small computation to find the number of seconds by which the slave is late.

- Bug #985: "Between RESET SLAVE and START SLAVE, SHOW SLAVE STATUS is wrong."
Now RESET SLAVE puts correct info in mi->host etc. A new test rpl_reset_slave
for that.
- Bug #986: "CHANGE MASTER & START SLAVE do not reset error columns in SHOW
SLAVE STATUS". Now these reset the errors.