poll.c
Removed mutex from epoll_wait.
Removed read and write mutexes from poll_waitevents.
session.c
If session_alloc fails, instead of calling directly free(session), call session_free, which decreases refcounter and only frees session when there are no references left.
Added session_unlink_dcb function which removes link from session and optionally sets the dcb->session pointer to NULL.
readconnection.h, readwritesplit.h
Added check fields to ROUTER_CLIENT_SES strct as well as lock, version number (not used yet) and closed flag.
mysql_backend.c
gw_read_backend_event: if backend_protocol->state was set to MYSQL_AUTH_RECV, function returned, which was unnecessary. If mysql state became MYSQL_AUTH_FAILED, router client session was closed. Removed unnecessary NULL checks because rsession is not allowed to be NULL. Similarly, removed other NULL checks and replaced them with asserts checking that router client session is not NULL at any phase.
mysql_client.c
Removed unused code blocks. Polished log commands. Replaced router client sessions NULL checks with asserts.
mysql_common.c
mysql_send_custom_error: if called with dcb == NULL, return.
readconnroute.c
Replaced malloc with calloc. Added functions rses_begin_router_action and rses_exit_router_action. If router client session is not closed, they take a lock and release it, respectively. Those functions are used for protecting all operations which modify the contents of router client session struct.
readwritesplit.c
Identical changes than in readconnroute.c
skygw_debug.h
Added check number and - macro for ROUTER_CLIENT_SES, and added COM_QUIT to STRPACKETTYPE.
- Checked argument types and counts
- Removed trailing line feeds
- Removed thread ids from error logs (they are used in trace / debug log
- Added some state information to dcbs
- Added prefix 'Error' or 'Fatal' to error logs.
- Switches all error logs to use flushing log write.
If backend connection can't be created, backend_dcb is not create, router client session is not created and what already is created in session_alloc, is freed.
mysql_client.c : gw_read_client_event
If session creation failed, then - instead of sending ok to client, "failed to create new session" is sent and client dcb is closed.
: gw_MySQLAccept
removed loop where accept was called again and again. With single thread looping forever is not possible because there's no one to free previously allocated resources.
If accept fails ten times in a row, then return without new client dcb.
session.c: Replaced free(session->router_sesision) with call to freeSession callback
users.c: Removed reference to uninitialized variable.
router.h: Added freeSession callback to function block.
mysql_backend.c: try to ensure that client dcb is still listening in epoll_wait when writing reply to it.
mysql_common.c: assert debug build is mysql_protocol_init is called with dcb == NULL
readconnroute.c, readwritesplit.c, debugcli.c and testroute.c : Added freeSession to function block and an inmplementation of it.
reworked the reference count mechanism on the session. Introduced a
FREE state for the session and alter the session destruction flow so
that we only remove the session when all the DCB's have singled they
have finished processing events for the DCB rather than when the first
thread decides to clsoe the DCB.
