/**
* Close a session with the router, this is the mechanism
* by which a router may cleanup data structure etc.
*
* @param instance The router instance data
* @param router_session The session being closed
*/
static void
closeSession(ROUTER *instance, void *router_session)
{
ROUTER_CLIENT_SES *router_cli_ses = (ROUTER_CLIENT_SES *)router_session;
DCB* backend_dcb;
CHK_CLIENT_RSES(router_cli_ses);
/**
* Lock router client session for secure read and update.
*/
if (rses_begin_locked_router_action(router_cli_ses))
{
/* decrease server current connection counter */
atomic_add(&router_cli_ses->backend->server->stats.n_current, -1);
backend_dcb = router_cli_ses->backend_dcb;
router_cli_ses->backend_dcb = NULL;
router_cli_ses->rses_closed = true;
/** Unlock */
rses_end_locked_router_action(router_cli_ses);
/**
* Close the backend server connection
*/
if (backend_dcb != NULL) {
CHK_DCB(backend_dcb);
dcb_close(backend_dcb);
}
}
}
/**
* We have data from the client, we must route it to the backend.
* This is simply a case of sending it to the connection that was
* chosen when we started the client session.
*
* @param instance The router instance
* @param router_session The router session returned from the newSession call
* @param queue The queue of data buffers to route
* @return if succeed 1, otherwise 0
*/
static int
routeQuery(ROUTER *instance, void *router_session, GWBUF *queue)
{
ROUTER_INSTANCE *inst = (ROUTER_INSTANCE *)instance;
ROUTER_CLIENT_SES *router_cli_ses = (ROUTER_CLIENT_SES *)router_session;
uint8_t *payload = GWBUF_DATA(queue);
int mysql_command;
int rc;
DCB* backend_dcb;
bool rses_is_closed;
inst->stats.n_queries++;
mysql_command = MYSQL_GET_COMMAND(payload);
/** Dirty read for quick check if router is closed. */
if (router_cli_ses->rses_closed)
{
rses_is_closed = true;
}
else
{
/**
* Lock router client session for secure read of DCBs
*/
rses_is_closed = !(rses_begin_locked_router_action(router_cli_ses));
}
if (!rses_is_closed)
{
backend_dcb = router_cli_ses->backend_dcb;
/** unlock */
rses_end_locked_router_action(router_cli_ses);
}
if (rses_is_closed || backend_dcb == NULL ||
SERVER_IS_DOWN(router_cli_ses->backend->server))
{
LOGIF(LT, (skygw_log_write(
LOGFILE_TRACE|LOGFILE_ERROR,
"Error : Failed to route MySQL command %d to backend "
"server.%s",
mysql_command,rses_is_closed ? " Session is closed." : "")));
rc = 0;
goto return_rc;
}
char* trc = NULL;
switch(mysql_command) {
case MYSQL_COM_CHANGE_USER:
rc = backend_dcb->func.auth(
backend_dcb,
NULL,
backend_dcb->session,
queue);
break;
case MYSQL_COM_QUERY:
LOGIF(LOGFILE_TRACE,(trc = modutil_get_SQL(queue)));
default:
rc = backend_dcb->func.write(backend_dcb, queue);
break;
}
LOGIF(LOGFILE_TRACE,skygw_log_write(
LOGFILE_DEBUG|LOGFILE_TRACE,
"Routed [%s] to '%s'%s%s",
STRPACKETTYPE(mysql_command),
backend_dcb->server->unique_name,
trc?": ":".",
trc?trc:""));
free(trc);
return_rc:
return rc;
}
/**
* We have data from the client, we must route it to the backend.
* This is simply a case of sending it to the connection that was
* chosen when we started the client session.
*
* @param instance The router instance
* @param router_session The router session returned from the newSession call
* @param queue The queue of data buffers to route
* @return The number of bytes sent
*/
static int
routeQuery(ROUTER *instance, void *router_session, GWBUF *queue)
{
ROUTER_INSTANCE *inst = (ROUTER_INSTANCE *)instance;
ROUTER_CLIENT_SES *router_cli_ses = (ROUTER_CLIENT_SES *)router_session;
uint8_t *payload = GWBUF_DATA(queue);
int mysql_command;
int rc;
DCB* backend_dcb;
bool rses_is_closed;
inst->stats.n_queries++;
mysql_command = MYSQL_GET_COMMAND(payload);
/** Dirty read for quick check if router is closed. */
if (router_cli_ses->rses_closed)
{
rses_is_closed = true;
}
else
{
/**
* Lock router client session for secure read of DCBs
*/
rses_is_closed = !(rses_begin_locked_router_action(router_cli_ses));
}
if (!rses_is_closed)
{
backend_dcb = router_cli_ses->backend_dcb;
/** unlock */
rses_end_locked_router_action(router_cli_ses);
}
if (rses_is_closed || backend_dcb == NULL)
{
LOGIF(LT, (skygw_log_write(
LOGFILE_TRACE,
"Error : Failed to route MySQL command %d to backend "
"server.",
mysql_command)));
goto return_rc;
}
switch(mysql_command) {
case MYSQL_COM_CHANGE_USER:
rc = backend_dcb->func.auth(
backend_dcb,
NULL,
backend_dcb->session,
queue);
break;
default:
rc = backend_dcb->func.write(backend_dcb, queue);
break;
}
CHK_PROTOCOL(((MySQLProtocol*)backend_dcb->protocol));
LOGIF(LD, (skygw_log_write(
LOGFILE_DEBUG,
"%lu [readconnroute:routeQuery] Routed command %d to dcb %p "
"with return value %d.",
pthread_self(),
mysql_command,
backend_dcb,
rc)));
return_rc:
return rc;
}