MaxScale/server/modules/include/shardrouter.h
2015-07-08 11:35:41 +01:00

251 lines
9.0 KiB
C

#ifndef _SHARDROUTER_H
#define _SHARDROUTER_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 shardrouter.h - The sharding router module header file
*
* @verbatim
* Revision History
*
* See GitHub https://github.com/mariadb-corporation/MaxScale
*
* @endverbatim
*/
#include <dcb.h>
#include <hashtable.h>
#include <mysql_client_server_protocol.h>
struct router_instance;
typedef enum {
TARGET_UNDEFINED = 0x00,
TARGET_MASTER = 0x01,
TARGET_SLAVE = 0x02,
TARGET_NAMED_SERVER = 0x04,
TARGET_ALL = 0x08,
TARGET_RLAG_MAX = 0x10,
TARGET_ANY = 0x20
} route_target_t;
#define TARGET_IS_UNDEFINED(t) (t == TARGET_UNDEFINED)
#define TARGET_IS_NAMED_SERVER(t) (t & TARGET_NAMED_SERVER)
#define TARGET_IS_ALL(t) (t & TARGET_ALL)
#define TARGET_IS_ANY(t) (t & TARGET_ANY)
typedef struct rses_property_st rses_property_t;
typedef struct router_client_session ROUTER_CLIENT_SES;
typedef enum rses_property_type_t {
RSES_PROP_TYPE_UNDEFINED=-1,
RSES_PROP_TYPE_SESCMD=0,
RSES_PROP_TYPE_FIRST = RSES_PROP_TYPE_SESCMD,
RSES_PROP_TYPE_TMPTABLES,
RSES_PROP_TYPE_LAST=RSES_PROP_TYPE_TMPTABLES,
RSES_PROP_TYPE_COUNT=RSES_PROP_TYPE_LAST+1
} rses_property_type_t;
/** default values for rwsplit configuration parameters */
#define CONFIG_MAX_SLAVE_CONN 1
#define CONFIG_MAX_SLAVE_RLAG -1 /*< not used */
#define CONFIG_SQL_VARIABLES_IN TYPE_ALL
#define GET_SELECT_CRITERIA(s) \
(strncmp(s,"LEAST_GLOBAL_CONNECTIONS", strlen("LEAST_GLOBAL_CONNECTIONS")) == 0 ? \
LEAST_GLOBAL_CONNECTIONS : ( \
strncmp(s,"LEAST_BEHIND_MASTER", strlen("LEAST_BEHIND_MASTER")) == 0 ? \
LEAST_BEHIND_MASTER : ( \
strncmp(s,"LEAST_ROUTER_CONNECTIONS", strlen("LEAST_ROUTER_CONNECTIONS")) == 0 ? \
LEAST_ROUTER_CONNECTIONS : ( \
strncmp(s,"LEAST_CURRENT_OPERATIONS", strlen("LEAST_CURRENT_OPERATIONS")) == 0 ? \
LEAST_CURRENT_OPERATIONS : UNDEFINED_CRITERIA))))
#define SUBSVC_IS_MAPPED(s) (s->state & SUBSVC_MAPPED)
#define SUBSVC_IS_CLOSED(s) (s->state & SUBSVC_CLOSED)
#define SUBSVC_IS_OK(s) (s->state & SUBSVC_OK)
#define SUBSVC_IS_WAITING(s) (s->state & SUBSVC_WAITING_RESULT)
/**
* Session variable command
*/
typedef struct mysql_sescmd_st {
#if defined(SS_DEBUG)
skygw_chk_t my_sescmd_chk_top;
#endif
rses_property_t* my_sescmd_prop; /*< parent property */
GWBUF* my_sescmd_buf; /*< query buffer */
unsigned char my_sescmd_packet_type;/*< packet type */
bool my_sescmd_is_replied; /*< is cmd replied to client */
#if defined(SS_DEBUG)
skygw_chk_t my_sescmd_chk_tail;
#endif
} mysql_sescmd_t;
/**
* Property structure
*/
struct rses_property_st {
#if defined(SS_DEBUG)
skygw_chk_t rses_prop_chk_top;
#endif
ROUTER_CLIENT_SES* rses_prop_rsession; /*< parent router session */
int rses_prop_refcount;
rses_property_type_t rses_prop_type;
union rses_prop_data {
mysql_sescmd_t sescmd;
HASHTABLE* temp_tables;
} rses_prop_data;
rses_property_t* rses_prop_next; /*< next property of same type */
#if defined(SS_DEBUG)
skygw_chk_t rses_prop_chk_tail;
#endif
};
typedef struct sescmd_cursor_st {
#if defined(SS_DEBUG)
skygw_chk_t scmd_cur_chk_top;
#endif
ROUTER_CLIENT_SES* scmd_cur_rses; /*< pointer to owning router session */
rses_property_t** scmd_cur_ptr_property; /*< address of pointer to owner property */
mysql_sescmd_t* scmd_cur_cmd; /*< pointer to current session command */
bool scmd_cur_active; /*< true if command is being executed */
#if defined(SS_DEBUG)
skygw_chk_t scmd_cur_chk_tail;
#endif
} sescmd_cursor_t;
typedef struct shardrouter_config_st {
int rw_max_slave_conn_percent;
int rw_max_slave_conn_count;
target_t rw_use_sql_variables_in;
} shard_config_t;
typedef enum{
SUBSVC_ALLOC = 0,
SUBSVC_OK = 1,
SUBSVC_CLOSED = (1<<1), /* This is when the service was cleanly closed */
SUBSVC_FAILED = (1<<2), /* This is when something went wrong */
SUBSVC_QUERY_ACTIVE = (1<<3),
SUBSVC_WAITING_RESULT = (1<<4),
SUBSVC_MAPPED = (1<<5)
}subsvc_state_t;
typedef struct subservice_t{
SERVICE* service;
SESSION* session;
DCB* dcb;
GWBUF* pending_cmd;
sescmd_cursor_t* scur;
int state;
int n_res_waiting;
bool mapped;
}SUBSERVICE;
/**
* Bitmask values for the router session's initialization. These values are used
* to prevent responses from internal commands being forwarded to the client.
*/
typedef enum shard_init_mask
{
INIT_READY = 0x0,
INIT_MAPPING = 0x1,
INIT_USE_DB = 0x02,
INIT_UNINT = 0x04
} shard_init_mask_t;
/**
* The client session structure used within this router.
*/
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. not used 4/14 */
bool rses_closed; /*< true when closeSession is called */
DCB* rses_client_dcb;
DCB* replydcb; /* DCB used to send the client write messages from the router itself */
DCB* routedcb; /* DCB used to send queued queries to the router */
MYSQL_session* rses_mysql_session;
/** Properties listed by their type */
rses_property_t* rses_properties[RSES_PROP_TYPE_COUNT];
shard_config_t rses_config; /*< copied config info from router instance */
int rses_capabilities; /*< input type, for example */
bool rses_autocommit_enabled;
bool rses_transaction_active;
struct router_instance *router; /*< The router instance */
struct router_client_session* next;
HASHTABLE* dbhash;
SUBSERVICE* *subservice;
int n_subservice;
bool hash_init;
SESSION* session;
GWBUF* queue;
char connect_db[MYSQL_DATABASE_MAXLEN+1]; /*< Database the user was trying to connect to */
shard_init_mask_t init; /*< Initialization state bitmask */
#if defined(SS_DEBUG)
skygw_chk_t rses_chk_tail;
#endif
};
/**
* 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 owning service */
ROUTER_CLIENT_SES* connections; /*< List of client connections */
SERVICE** services; /*< List of services to map for sharding */
int n_services;
SUBSERVICE* all_subsvc;
SPINLOCK lock; /*< Lock for the instance data */
shard_config_t shardrouter_config; /*< expanded config info from SERVICE */
int shardrouter_version;/*< version number for router's config */
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 */
bool available_slaves; /*< The router has some slaves available */
DCB* dumy_backend;
} ROUTER_INSTANCE;
#define BACKEND_TYPE(b) (SERVER_IS_MASTER((b)->backend_server) ? BE_MASTER : \
(SERVER_IS_SLAVE((b)->backend_server) ? BE_SLAVE : BE_UNDEFINED));
bool subsvc_is_valid(SUBSERVICE*);
#endif /*< _SHARDROUTER_H */