89 lines
3.1 KiB
C
89 lines
3.1 KiB
C
#ifndef _READCONNECTION_H
|
|
#define _READCONNECTION_H
|
|
/*
|
|
* This file is distributed as part of the MariaDB Corporation MaxScale. 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 MariaDB Corporation Ab 2013-2014
|
|
*/
|
|
|
|
/**
|
|
* @file readconnection.h - The read connection balancing query module heder file
|
|
*
|
|
* @verbatim
|
|
* Revision History
|
|
*
|
|
* Date Who Description
|
|
* 14/06/13 Mark Riddoch Initial implementation
|
|
* 27/06/14 Mark Riddoch Addition of server weight percentage
|
|
*
|
|
* @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 *server; /*< The server itself */
|
|
int current_connection_count; /*< Number of connections to the server */
|
|
int weight; /*< Desired routing weight */
|
|
} 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 *backend; /*< Backend used by the client session */
|
|
DCB *backend_dcb; /*< DCB Connection to the backend */
|
|
struct router_client_session *next;
|
|
int rses_capabilities; /*< input type, for example */
|
|
#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 */
|
|
} ROUTER_STATS;
|
|
|
|
|
|
/**
|
|
* The per instance data for the router.
|
|
*/
|
|
typedef struct router_instance {
|
|
SERVICE *service; /*< Pointer to the service using this router */
|
|
ROUTER_CLIENT_SES *connections; /*< Link list of all the client connections */
|
|
SPINLOCK lock; /*< Spinlock for the instance data */
|
|
BACKEND **servers; /*< List of backend servers */
|
|
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;
|
|
} ROUTER_INSTANCE;
|
|
#endif
|