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Editing: slave.h
/* Copyright (c) 2000, 2016, Oracle and/or its affiliates. Copyright (c) 2009, 2016, MariaDB This program 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 of the License. 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 St, Fifth Floor, Boston, MA 02110-1335 USA */ #ifndef SLAVE_H #define SLAVE_H /** MASTER_DELAY can be at most (1 << 31) - 1. */ #define MASTER_DELAY_MAX (0x7FFFFFFF) #if INT_MAX < 0x7FFFFFFF #error "don't support platforms where INT_MAX < 0x7FFFFFFF" #endif /** @defgroup Replication Replication @{ @file */ /** Some of defines are need in parser even though replication is not compiled in (embedded). */ /** The maximum is defined as (ULONG_MAX/1000) with 4 bytes ulong */ #define SLAVE_MAX_HEARTBEAT_PERIOD 4294967 #ifdef HAVE_REPLICATION #include "log.h" #include "my_list.h" #include "rpl_filter.h" #include "rpl_tblmap.h" #include "rpl_gtid.h" #include "log_event.h" #define SLAVE_NET_TIMEOUT 60 #define MAX_SLAVE_ERROR ER_ERROR_LAST+1 #define MAX_REPLICATION_THREAD 64 // Forward declarations class Relay_log_info; class Master_info; class Master_info_index; struct rpl_group_info; struct rpl_parallel_thread; int init_intvar_from_file(int* var, IO_CACHE* f, int default_val); int init_strvar_from_file(char *var, int max_size, IO_CACHE *f, const char *default_val); int init_floatvar_from_file(float* var, IO_CACHE* f, float default_val); int init_dynarray_intvar_from_file(DYNAMIC_ARRAY* arr, IO_CACHE* f); /***************************************************************************** MySQL Replication Replication is implemented via two types of threads: I/O Thread - One of these threads is started for each master server. They maintain a connection to their master server, read log events from the master as they arrive, and queues them into a single, shared relay log file. A Master_info represents each of these threads. SQL Thread - One of these threads is started and reads from the relay log file, executing each event. A Relay_log_info represents this thread. Buffering in the relay log file makes it unnecessary to reread events from a master server across a slave restart. It also decouples the slave from the master where long-running updates and event logging are concerned--ie it can continue to log new events while a slow query executes on the slave. *****************************************************************************/ /* MUTEXES in replication: LOCK_active_mi: [note: this was originally meant for multimaster, to switch from a master to another, to protect active_mi] It is used to SERIALIZE ALL administrative commands of replication: START SLAVE, STOP SLAVE, CHANGE MASTER, RESET SLAVE, end_slave() (when mysqld stops) [init_slave() does not need it it's called early]. Any of these commands holds the mutex from the start till the end. This thus protects us against a handful of deadlocks (consider start_slave_thread() which, when starting the I/O thread, releases mi->run_lock, keeps rli->run_lock, and tries to re-acquire mi->run_lock). Currently active_mi never moves (it's created at startup and deleted at shutdown, and not changed: it always points to the same Master_info struct), because we don't have multimaster. So for the moment, mi does not move, and mi->rli does not either. In Master_info: run_lock, data_lock run_lock protects all information about the run state: slave_running, thd and the existence of the I/O thread (to stop/start it, you need this mutex). data_lock protects some moving members of the struct: counters (log name, position) and relay log (MYSQL_BIN_LOG object). In Relay_log_info: run_lock, data_lock see Master_info However, note that run_lock does not protect Relay_log_info.run_state; that is protected by data_lock. Order of acquisition: if you want to have LOCK_active_mi and a run_lock, you must acquire LOCK_active_mi first. In MYSQL_BIN_LOG: LOCK_log, LOCK_index of the binlog and the relay log LOCK_log: when you write to it. LOCK_index: when you create/delete a binlog (so that you have to update the .index file). */ extern ulong master_retry_count; extern MY_BITMAP slave_error_mask; extern char slave_skip_error_names[]; extern bool use_slave_mask; extern char slave_transaction_retry_error_names[]; extern uint *slave_transaction_retry_errors; extern uint slave_transaction_retry_error_length; extern char *slave_load_tmpdir; extern char *master_info_file; extern MYSQL_PLUGIN_IMPORT char *relay_log_info_file; extern char *opt_relay_logname, *opt_relaylog_index_name; extern my_bool opt_skip_slave_start, opt_reckless_slave; extern my_bool opt_log_slave_updates; extern char *opt_slave_skip_errors; extern char *opt_slave_transaction_retry_errors; extern my_bool opt_replicate_annotate_row_events; extern ulonglong relay_log_space_limit; extern ulonglong opt_read_binlog_speed_limit; extern ulonglong slave_skipped_errors; extern const char *relay_log_index; extern const char *relay_log_basename; /* 4 possible values for Master_info::slave_running and Relay_log_info::slave_running. The values 0,1,2,3 are very important: to keep the diff small, I didn't substitute places where we use 0/1 with the newly defined symbols. So don't change these values. The same way, code is assuming that in Relay_log_info we use only values 0/1. I started with using an enum, but enum_variable=1; is not legal so would have required many line changes. */ #define MYSQL_SLAVE_NOT_RUN 0 #define MYSQL_SLAVE_RUN_NOT_CONNECT 1 #define MYSQL_SLAVE_RUN_CONNECT 2 #define MYSQL_SLAVE_RUN_READING 3 #define RPL_LOG_NAME (rli->group_master_log_name[0] ? rli->group_master_log_name :\ "FIRST") #define IO_RPL_LOG_NAME (mi->master_log_name[0] ? mi->master_log_name :\ "FIRST") /* If the following is set, if first gives an error, second will be tried. Otherwise, if first fails, we fail. */ #define SLAVE_FORCE_ALL 4 /* Values for the option --replicate-events-marked-for-skip. Must match the names in replicate_events_marked_for_skip_names in sys_vars.cc */ #define RPL_SKIP_REPLICATE 0 #define RPL_SKIP_FILTER_ON_SLAVE 1 #define RPL_SKIP_FILTER_ON_MASTER 2 int init_slave(); int init_recovery(Master_info* mi, const char** errmsg); bool init_slave_skip_errors(const char* arg); bool init_slave_transaction_retry_errors(const char* arg); int register_slave_on_master(MYSQL* mysql); int terminate_slave_threads(Master_info* mi, int thread_mask, bool skip_lock = 0); int start_slave_threads(THD *thd, bool need_slave_mutex, bool wait_for_start, Master_info* mi, const char* master_info_fname, const char* slave_info_fname, int thread_mask); /* cond_lock is usually same as start_lock. It is needed for the case when start_lock is 0 which happens if start_slave_thread() is called already inside the start_lock section, but at the same time we want a mysql_cond_wait() on start_cond, start_lock */ int start_slave_thread( #ifdef HAVE_PSI_INTERFACE PSI_thread_key thread_key, #endif pthread_handler h_func, mysql_mutex_t *start_lock, mysql_mutex_t *cond_lock, mysql_cond_t *start_cond, volatile uint *slave_running, volatile ulong *slave_run_id, Master_info *mi); /* If fd is -1, dump to NET */ int mysql_table_dump(THD* thd, const char* db, const char* tbl_name, int fd = -1); /* retrieve table from master and copy to slave*/ int fetch_master_table(THD* thd, const char* db_name, const char* table_name, Master_info* mi, MYSQL* mysql, bool overwrite); void show_master_info_get_fields(THD *thd, List<Item> *field_list, bool full, size_t gtid_pos_length); bool show_master_info(THD* thd, Master_info* mi, bool full); bool show_all_master_info(THD* thd); void show_binlog_info_get_fields(THD *thd, List<Item> *field_list); bool show_binlog_info(THD* thd); bool rpl_master_has_bug(const Relay_log_info *rli, uint bug_id, bool report, bool (*pred)(const void *), const void *param, bool maria_master= false); bool rpl_master_erroneous_autoinc(THD* thd); const char *print_slave_db_safe(const char *db); void skip_load_data_infile(NET* net); void slave_prepare_for_shutdown(); void end_slave(); /* release slave threads */ void close_active_mi(); /* clean up slave threads data */ void clear_until_condition(Relay_log_info* rli); void clear_slave_error(Relay_log_info* rli); void end_relay_log_info(Relay_log_info* rli); void init_thread_mask(int* mask,Master_info* mi,bool inverse); Format_description_log_event * read_relay_log_description_event(IO_CACHE *cur_log, ulonglong start_pos, const char **errmsg); int init_relay_log_pos(Relay_log_info* rli,const char* log,ulonglong pos, bool need_data_lock, const char** errmsg, bool look_for_description_event); int purge_relay_logs(Relay_log_info* rli, THD *thd, bool just_reset, const char** errmsg); void set_slave_thread_options(THD* thd); void set_slave_thread_default_charset(THD *thd, rpl_group_info *rgi); int rotate_relay_log(Master_info* mi); int has_temporary_error(THD *thd); int sql_delay_event(Log_event *ev, THD *thd, rpl_group_info *rgi); int apply_event_and_update_pos(Log_event* ev, THD* thd, struct rpl_group_info *rgi); int apply_event_and_update_pos_for_parallel(Log_event* ev, THD* thd, struct rpl_group_info *rgi); int init_intvar_from_file(int* var, IO_CACHE* f, int default_val); int init_floatvar_from_file(float* var, IO_CACHE* f, float default_val); int init_strvar_from_file(char *var, int max_size, IO_CACHE *f, const char *default_val); int init_dynarray_intvar_from_file(DYNAMIC_ARRAY* arr, IO_CACHE* f); pthread_handler_t handle_slave_io(void *arg); void slave_output_error_info(rpl_group_info *rgi, THD *thd); pthread_handler_t handle_slave_sql(void *arg); bool net_request_file(NET* net, const char* fname); void slave_background_kill_request(THD *to_kill); void slave_background_gtid_pos_create_request (rpl_slave_state::gtid_pos_table *table_entry); void slave_background_gtid_pending_delete_request(void); extern Master_info *active_mi; /* active_mi for multi-master */ extern Master_info *default_master_info; /* To replace active_mi */ extern Master_info_index *master_info_index; extern LEX_CSTRING default_master_connection_name; extern my_bool replicate_same_server_id; extern int disconnect_slave_event_count, abort_slave_event_count ; /* the master variables are defaults read from my.cnf or command line */ extern uint report_port; extern char *master_info_file, *report_user; extern char *report_host, *report_password; extern I_List<THD> threads; /* Check that a binlog event (read from the relay log) is valid to update last_master_timestamp. That is, a valid event is one with a consistent timestamp which originated from a primary server. */ static inline bool event_can_update_last_master_timestamp(Log_event *ev) { return ev && !(ev->is_artificial_event() || ev->is_relay_log_event() || (ev->when == 0)); } #else #define close_active_mi() /* no-op */ #endif /* HAVE_REPLICATION */ /* masks for start/stop operations on io and sql slave threads */ #define SLAVE_IO 1 #define SLAVE_SQL 2 /** @} (end of group Replication) */ #endif
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