Moved the check for transaction state before certification step
into separate method abort_or_interrupted() which will check the state
and adjust state and client_state error status accordingly.
Moved the check for abort_or_interrupted() to happen before
the state is changed to certifying and write set data is appended.
This makes the check atomic and reduces the probability of race
conditions. After this check we rely on provider side transaction
state management and error reporting until the certification step
is over.
Change to public API: Pass client_state mutex wrappend in unique_lock
object to client_service::interrupted() call. This way the DBMS side
has a control to the lock object in case it needs to unlock it
temporarily. The underlying mutex will always be locked when the lock
object is passed via interrupted() call.
Other: Allow server_state change from donor to connected. This may
happen if the joiner crashes during SST and the provider reports
it before the DBMS side SST mechanism detects the error.
* Adds method wsrep::transaction::streaming_step() so that there is a
single place where streaming context unit counter is udpated.
The method also checks that some data has been generated before
attempting fragment replication.
* Emit a warning if there is an attempt to replicate a fragment and
there is no data to replicate.
* Added server_id into transaction in order to be able to stop
streaming applier during high priority BF abort
* Added missing commit fragment applying
* Don't clear fragments for replaying SR transaction
* Added after applying call for high priority threads in order to
avoid client mode complexity in after_statement() call and
make high prio transaction cleanup possible
* Mask connection failed error with deadlock error if provider
returns connection failed and the transaction was BF aborted
