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.
For tables with metadata sizes ranging from 251 to 255 the size
of the event data (m_data_size) was being improperly calculated
in the Table_map_log_event constructor. This was due to the fact
that when writing the Table_map_log_event body (in
Table_map_log_event::write_data_body) a call to net_store_length
is made for packing the m_field_metadata_size. It happens that
net_store_length uses *one* byte for storing
m_field_metadata_size when it is smaller than 251 but *three*
bytes when it exceeds that value. BUG 42749 had already
pinpointed and fix this fact, but the fix was incomplete, as the
calculation in the Table_map_log_event constructor considers 255
instead of 251 as the threshold to increment m_data_size by
three. Thence, the window for having a mismatch between the
number of bytes written and the number of bytes accounted in the
event length (m_data_size) was left open for
m_field_metadata_size values between 251 and 255.
We fix this by changing the condition in the Table_map_log_event
constructor to match the one in the net_store_length, ie,
increment one byte if m_field_metadata_size < 251 and three if it
exceeds this value.
