The code only handled the basic version of the command, returning incorrect
results if modifiers were used. The code is now removed, causing the command
to be routed to the backend of the current database. This will give correct
results as long as that backend contains all the tables of the database e.g.
no table sharding.
Some SQL clients may default to a different authentication plugin than
"mysql_native_password". Since this is the only one supported by MySQL-
authenticator, the client is instructed to swap its plugin.
Because runtime changes are performed one at a time, adding replication credentials
to a mariadbmon which didn't have any would cause an error to be printed, and
the monitor would not start.
This is now fixed by allowing replication_user without replication_password. This
is not an ideal solution as a configuration file with only replication_user would be
accepted. Also, when adding the credentials to a monitor, replication_user must be
given first to avoid the error.
If a result consists of only OK packets, they would be processed
recursively which most of the time leads to a stack overflow. This can be
prevented by consuming all OK packets in the result in one go.
- Check textual prepared statements for use of columns to be masked
in conjunction with functions.
- Check binary prepared statements for use of columns to be masked
in conjunction with functions.
- Prevent creation of textual prepared statement from variable.
As the masking filter must reject statements that use columns to be
masked as arguments to functions, a statement that cannot be fully
parsed must be rejected. Unless a statement can be fully parsed we
cannot know whether such usage occurs.
By always setting the position of the next event, the replication cannot
break if the slave server has to reconnect after receiving an event that
was generated by the binlogfilter.
If a routing of a queued query caused it to be put back on the query
queue, the order in which the queue was reorganized was wrong. The first
query would get appended as the last query which caused the order to be
reversed.
Th discarding of connections in maintenance mode must be done after any
results have been written to them. This prevents closing of the connection
before the actual result is returned.
The candidate selection code used default values that would cause reads
past buffers. The code could also dereference the end iterator which
causes undefined behavior.
This fixes some situations where MaxAdmin/MaxCtrl would block and wait
until a monitor operation or tick is complete. This also fixes a deadlock
caused by calling monitor diagnostics inside a monitor script.
Concurrency is enabled by adding one mutex per server object to protect
array-like fields from concurrent reading/writing.
Queries in the query queue need to be explicitly parsed since they are
stored in a single buffer and thus share the query classification
information. In the next major version this should be changed into an
array of individual buffers instead of a shared buffer.
If a DCB was closed and a hangup event was sent to it via
dcb_hangup_foreach shortly after it was closed, the DCB would still
receive it even if it was closed. To prevent this, events must only be
delivered to DCBs if they haven't been closed.
The protocol should not track the session state as the parsing is quite
expensive with the current code. This change is a workaround that enables
the parsing only when required. A proper way to handle this would be to do
all the response processing in one place thus avoiding the duplication of
work.
Given the fact that there exist only three possible categories, the map
can be replaced with a static array that needs no memory
allocations. Making this array thread-local allows it to be reused which
places an upper limit on the number of memory allocations.
The monitor now continuously updates a list of enabled server events. When
promoting a new master in failover/switchover, only events that were enabled
on the previous master are enabled on the new. This avoids enabling events
that may have been disabled on the master yet stayed in the SLAVESIDE_DISABLED-
state on the slave.
In the case of reset-replication command, events on the new master are only
enabled if the monitor had a master when the command was launched. Otherwise
all events remain disabled.
The documentation stated that at most `max_sescmd_history` commands were
kept but in reality the number of commands kept in the history was one
command smaller than what was documented.
