/**
* Creates MySQL protocol structure
*
* @param dcb * Must be non-NULL.
* @param fd
*
* @return
*
*
* @details Protocol structure does not have fd because dcb is not
* connected yet.
*
*/
MySQLProtocol* mysql_protocol_init(
DCB* dcb,
int fd)
{
MySQLProtocol* p;
p = (MySQLProtocol *) calloc(1, sizeof(MySQLProtocol));
ss_dassert(p != NULL);
if (p == NULL) {
int eno = errno;
errno = 0;
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"%lu [mysql_init_protocol] MySQL protocol init failed : "
"memory allocation due error %d, %s.",
pthread_self(),
eno,
strerror(eno))));
goto return_p;
}
p->state = MYSQL_ALLOC;
#if defined(SS_DEBUG)
p->protocol_chk_top = CHK_NUM_PROTOCOL;
p->protocol_chk_tail = CHK_NUM_PROTOCOL;
#endif
/*< Assign fd with protocol */
p->fd = fd;
p->owner_dcb = dcb;
CHK_PROTOCOL(p);
return_p:
return p;
}
/**
* 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;
}
