readwritesplit.h:Removed invalid macros which assumed that ROUTER_CLIENT_SES->rses_backend_ref always pointed to valid and used backend reference and thus included potential risk of NULL-pointer refernce.
mysql_backend.c and mysql_client.c:avoid executing CHK_PROTOCOL(p) after original DCB has been released the memory.
readwritesplit.c:Replaced RSES_CLEINT_DCB macro with a function which returns client DCB for a given router client session.
Support for running out of disk space in the binlog router
Support for COM_PING & COM_STATISTICS added in the binlog router
Addition of binlogdir router option
tee.c:closeSession removed unnecessary dcb_free, router/service closes all backend DCBs and the client DCB, and client DCB is the one that was tried to free in closeSession.
readwritesplit.c:routeQuery now handles untyped and typed GWBUFs. Untyped means that read buffer may consist of incomplete and multiple MySQL packets. Typed buffer always consists of a single MySQL packet (which can be split to many buffers inside GWBUF).
Fixed Coverity cases #84840 and #84841
dbshard.h:removed unnecessary code
dbshard.c:removed unnecessary code, cleaned up a bit and made some required changes
readwritesplit.c:removed two unnecessary variable assignments.
mysql_mon.c: Added back server state logging to Debug build.
query_classifier.cc: removed some extra debug code, cleaned up a bit function documentation.
mysql_client_server_protocol.h, mysql_backend.c, mysql_common.c: changed some variables to signed ones to enable checking of calculations in the code.
skygw_utils.cc: removed erroneous debug assertion.
if (func.auth ==)gw_change_user->gw_send_change_user_to_backend is called before backend has its scramble, auth packet is set to backend's delauqueue instead of writing it to backend. When backend_write_delayqueue is called COM_CHANGE_USER packets are rewritten with backend's current data.
Execution of session commands failed because session commands and normal sql statements were executed in a wrong order if backend was executing previous session command while new sql stmt was routed to that backend. There was a window where ordering went wrong.
It is possible that one normal sql stmt arrives while previous sescmds are still being executed.
Introduced a new member in backend_ref_t structure, bref_pending_cmd where new sql stmt pointer is stored in that case. When sescmds are executed completely, that command is automatically executed next.
