diff options
Diffstat (limited to 'sql/log_event.h')
| -rw-r--r-- | sql/log_event.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/sql/log_event.h b/sql/log_event.h index 0b4c63a73af..cd5e659c910 100644 --- a/sql/log_event.h +++ b/sql/log_event.h @@ -250,6 +250,7 @@ struct sql_ex_info #define EXECUTE_LOAD_QUERY_EXTRA_HEADER_LEN (4 + 4 + 4 + 1) #define EXECUTE_LOAD_QUERY_HEADER_LEN (QUERY_HEADER_LEN + EXECUTE_LOAD_QUERY_EXTRA_HEADER_LEN) #define INCIDENT_HEADER_LEN 2 +#define HEARTBEAT_HEADER_LEN 0 /* Max number of possible extra bytes in a replication event compared to a packet (i.e. a query) sent from client to master; @@ -575,6 +576,12 @@ enum Log_event_type INCIDENT_EVENT= 26, /* + Heartbeat event to be send by master at its idle time + to ensure master's online status to slave + */ + HEARTBEAT_LOG_EVENT= 27, + + /* Add new events here - right above this comment! Existing events (except ENUM_END_EVENT) should never change their numbers */ @@ -689,6 +696,20 @@ typedef struct st_print_event_info } PRINT_EVENT_INFO; #endif +/** + the struct aggregates two paramenters that identify an event + uniquely in scope of communication of a particular master and slave couple. + I.e there can not be 2 events from the same staying connected master which + have the same coordinates. + @note + Such identifier is not yet unique generally as the event originating master + is resetable. Also the crashed master can be replaced with some other. +*/ +struct event_coordinates +{ + char * file_name; // binlog file name (directories stripped) + my_off_t pos; // event's position in the binlog file +}; /** @class Log_event @@ -3920,6 +3941,42 @@ static inline bool copy_event_cache_to_file_and_reinit(IO_CACHE *cache, reinit_io_cache(cache, WRITE_CACHE, 0, FALSE, TRUE); } +#ifndef MYSQL_CLIENT +/***************************************************************************** + + Heartbeat Log Event class + + Replication event to ensure to slave that master is alive. + The event is originated by master's dump thread and sent straight to + slave without being logged. Slave itself does not store it in relay log + but rather uses a data for immediate checks and throws away the event. + + Two members of the class log_ident and Log_event::log_pos comprise + @see the event_coordinates instance. The coordinates that a heartbeat + instance carries correspond to the last event master has sent from + its binlog. + + ****************************************************************************/ +class Heartbeat_log_event: public Log_event +{ +public: + Heartbeat_log_event(const char* buf, uint event_len, + const Format_description_log_event* description_event); + Log_event_type get_type_code() { return HEARTBEAT_LOG_EVENT; } + bool is_valid() const + { + return (log_ident != NULL && + log_pos >= BIN_LOG_HEADER_SIZE); + } + const char * get_log_ident() { return log_ident; } + uint get_ident_len() { return ident_len; } + +private: + const char* log_ident; + uint ident_len; +}; +#endif + /** @} (end of group Replication) */ |