#ifndef _RWSPLITROUTER_H
#define _RWSPLITROUTER_H
/*
 * This file is distributed as part of the SkySQL Gateway.  It is free
 * software: you can redistribute it and/or modify it under the terms of the
 * GNU General Public License as published by the Free Software Foundation,
 * version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Copyright SkySQL Ab 2013
 */

/**
 * @file router.h - The read write split router module heder file
 *
 * @verbatim
 * Revision History
 *
 * bazaar..
 *
 * @endverbatim
 */

#include <dcb.h>

/**
 * Internal structure used to define the set of backend servers we are routing
 * connections to. This provides the storage for routing module specific data
 * that is required for each of the backend servers.
 */
typedef struct backend {
        SERVER* backend_server;	     /*< The server itself                   */
        int     backend_conn_count;  /*< Number of connections to the server */
} BACKEND;

/**
 * The client session structure used within this router.
 */
typedef struct router_client_session {
#if defined(SS_DEBUG)
        skygw_chk_t     rses_chk_top;
#endif
        SPINLOCK        rses_lock;     /*< protects rses_deleted                 */
        int             rses_versno;   /*< even = no active update, else odd     */
        bool            rses_closed;   /*< true when closeSession is called      */
        BACKEND*        be_slave;      /*< Slave backend used by client session  */
        BACKEND*        be_master;     /*< Master backend used by client session */
        DCB*            slave_dcb;     /*< Slave connection                      */
        DCB*            master_dcb;    /*< Master connection                     */
        struct router_client_session* next;
#if defined(SS_DEBUG)
        skygw_chk_t     rses_chk_tail;
#endif
} ROUTER_CLIENT_SES;

/**
 * The statistics for this router instance
 */
typedef struct {
	int		n_sessions;	/*< Number sessions created        */
	int		n_queries;	/*< Number of queries forwarded    */
	int		n_master;	/*< Number of stmts sent to master */
	int		n_slave;	/*< Number of stmts sent to slave  */
	int		n_all;		/*< Number of stmts sent to all    */
} ROUTER_STATS;


/**
 * The per instance data for the router.
 */
typedef struct router_instance {
	SERVICE*                service;     /*< Pointer to service                 */
	ROUTER_CLIENT_SES*      connections; /*< List of client connections         */
	SPINLOCK                lock;	     /*< Lock for the instance data         */
	BACKEND**               servers;     /*< Backend servers                    */
	BACKEND*                master;      /*< NULL or pointer                    */
        unsigned int	        bitmask;     /*< Bitmask to apply to server->status */
	unsigned int	        bitvalue;    /*< Required value of server->status   */
	ROUTER_STATS            stats;       /*< Statistics for this router         */
        struct router_instance* next;        /*< Next router on the list            */
} ROUTER_INSTANCE;


#endif