1 /* Copyright (c) 2000, 2016, Oracle and/or its affiliates.
2    Copyright (c) 2009, 2016, MariaDB
3 
4    This program is free software; you can redistribute it and/or modify
5    it under the terms of the GNU General Public License as published by
6    the Free Software Foundation; version 2 of the License.
7 
8    This program is distributed in the hope that it will be useful,
9    but WITHOUT ANY WARRANTY; without even the implied warranty of
10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11    GNU General Public License for more details.
12 
13    You should have received a copy of the GNU General Public License
14    along with this program; if not, write to the Free Software
15    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335  USA */
16 
17 #ifndef SLAVE_H
18 #define SLAVE_H
19 
20 /**
21   MASTER_DELAY can be at most (1 << 31) - 1.
22 */
23 #define MASTER_DELAY_MAX (0x7FFFFFFF)
24 #if INT_MAX < 0x7FFFFFFF
25 #error "don't support platforms where INT_MAX < 0x7FFFFFFF"
26 #endif
27 
28 /**
29   @defgroup Replication Replication
30   @{
31 
32   @file
33 */
34 
35 /**
36    Some of defines are need in parser even though replication is not
37    compiled in (embedded).
38 */
39 
40 /**
41    The maximum is defined as (ULONG_MAX/1000) with 4 bytes ulong
42 */
43 #define SLAVE_MAX_HEARTBEAT_PERIOD 4294967
44 
45 #ifdef HAVE_REPLICATION
46 
47 #include "log.h"
48 #include "my_list.h"
49 #include "rpl_filter.h"
50 #include "rpl_tblmap.h"
51 #include "rpl_gtid.h"
52 
53 #define SLAVE_NET_TIMEOUT  60
54 
55 #define MAX_SLAVE_ERROR    ER_ERROR_LAST+1
56 
57 #define MAX_REPLICATION_THREAD 64
58 
59 // Forward declarations
60 class Relay_log_info;
61 class Master_info;
62 class Master_info_index;
63 struct rpl_group_info;
64 struct rpl_parallel_thread;
65 
66 int init_intvar_from_file(int* var, IO_CACHE* f, int default_val);
67 int init_strvar_from_file(char *var, int max_size, IO_CACHE *f,
68                           const char *default_val);
69 int init_floatvar_from_file(float* var, IO_CACHE* f, float default_val);
70 int init_dynarray_intvar_from_file(DYNAMIC_ARRAY* arr, IO_CACHE* f);
71 
72 /*****************************************************************************
73 
74   MySQL Replication
75 
76   Replication is implemented via two types of threads:
77 
78     I/O Thread - One of these threads is started for each master server.
79                  They maintain a connection to their master server, read log
80                  events from the master as they arrive, and queues them into
81                  a single, shared relay log file.  A Master_info
82                  represents each of these threads.
83 
84     SQL Thread - One of these threads is started and reads from the relay log
85                  file, executing each event.  A Relay_log_info
86                  represents this thread.
87 
88   Buffering in the relay log file makes it unnecessary to reread events from
89   a master server across a slave restart.  It also decouples the slave from
90   the master where long-running updates and event logging are concerned--ie
91   it can continue to log new events while a slow query executes on the slave.
92 
93 *****************************************************************************/
94 
95 /*
96   MUTEXES in replication:
97 
98   LOCK_active_mi: [note: this was originally meant for multimaster, to switch
99   from a master to another, to protect active_mi] It is used to SERIALIZE ALL
100   administrative commands of replication: START SLAVE, STOP SLAVE, CHANGE
101   MASTER, RESET SLAVE, end_slave() (when mysqld stops) [init_slave() does not
102   need it it's called early]. Any of these commands holds the mutex from the
103   start till the end. This thus protects us against a handful of deadlocks
104   (consider start_slave_thread() which, when starting the I/O thread, releases
105   mi->run_lock, keeps rli->run_lock, and tries to re-acquire mi->run_lock).
106 
107   Currently active_mi never moves (it's created at startup and deleted at
108   shutdown, and not changed: it always points to the same Master_info struct),
109   because we don't have multimaster. So for the moment, mi does not move, and
110   mi->rli does not either.
111 
112   In Master_info: run_lock, data_lock
113   run_lock protects all information about the run state: slave_running, thd
114   and the existence of the I/O thread (to stop/start it, you need this mutex).
115   data_lock protects some moving members of the struct: counters (log name,
116   position) and relay log (MYSQL_BIN_LOG object).
117 
118   In Relay_log_info: run_lock, data_lock
119   see Master_info
120   However, note that run_lock does not protect
121   Relay_log_info.run_state; that is protected by data_lock.
122 
123   Order of acquisition: if you want to have LOCK_active_mi and a run_lock, you
124   must acquire LOCK_active_mi first.
125 
126   In MYSQL_BIN_LOG: LOCK_log, LOCK_index of the binlog and the relay log
127   LOCK_log: when you write to it. LOCK_index: when you create/delete a binlog
128   (so that you have to update the .index file).
129 */
130 
131 extern ulong master_retry_count;
132 extern MY_BITMAP slave_error_mask;
133 extern char slave_skip_error_names[];
134 extern bool use_slave_mask;
135 extern char slave_transaction_retry_error_names[];
136 extern uint *slave_transaction_retry_errors;
137 extern uint slave_transaction_retry_error_length;
138 extern char *slave_load_tmpdir;
139 extern char *master_info_file;
140 extern MYSQL_PLUGIN_IMPORT char *relay_log_info_file;
141 extern char *opt_relay_logname, *opt_relaylog_index_name;
142 extern my_bool opt_skip_slave_start, opt_reckless_slave;
143 extern my_bool opt_log_slave_updates;
144 extern char *opt_slave_skip_errors;
145 extern char *opt_slave_transaction_retry_errors;
146 extern my_bool opt_replicate_annotate_row_events;
147 extern ulonglong relay_log_space_limit;
148 extern ulonglong opt_read_binlog_speed_limit;
149 extern ulonglong slave_skipped_errors;
150 extern const char *relay_log_index;
151 extern const char *relay_log_basename;
152 
153 /*
154   4 possible values for Master_info::slave_running and
155   Relay_log_info::slave_running.
156   The values 0,1,2,3 are very important: to keep the diff small, I didn't
157   substitute places where we use 0/1 with the newly defined symbols.
158   So don't change these values.
159   The same way, code is assuming that in Relay_log_info we use only values
160   0/1.
161   I started with using an enum, but
162   enum_variable=1; is not legal so would have required many line changes.
163 */
164 #define MYSQL_SLAVE_NOT_RUN         0
165 #define MYSQL_SLAVE_RUN_NOT_CONNECT 1
166 #define MYSQL_SLAVE_RUN_CONNECT     2
167 #define MYSQL_SLAVE_RUN_READING     3
168 
169 #define RPL_LOG_NAME (rli->group_master_log_name[0] ? rli->group_master_log_name :\
170  "FIRST")
171 #define IO_RPL_LOG_NAME (mi->master_log_name[0] ? mi->master_log_name :\
172  "FIRST")
173 
174 /*
175   If the following is set, if first gives an error, second will be
176   tried. Otherwise, if first fails, we fail.
177 */
178 #define SLAVE_FORCE_ALL 4
179 
180 /*
181   Values for the option --replicate-events-marked-for-skip.
182   Must match the names in replicate_events_marked_for_skip_names in sys_vars.cc
183 */
184 #define RPL_SKIP_REPLICATE 0
185 #define RPL_SKIP_FILTER_ON_SLAVE 1
186 #define RPL_SKIP_FILTER_ON_MASTER 2
187 
188 
189 int init_slave();
190 int init_recovery(Master_info* mi, const char** errmsg);
191 bool init_slave_skip_errors(const char* arg);
192 bool init_slave_transaction_retry_errors(const char* arg);
193 int register_slave_on_master(MYSQL* mysql);
194 int terminate_slave_threads(Master_info* mi, int thread_mask,
195 			     bool skip_lock = 0);
196 int start_slave_threads(THD *thd,
197                         bool need_slave_mutex, bool wait_for_start,
198 			Master_info* mi, const char* master_info_fname,
199 			const char* slave_info_fname, int thread_mask);
200 /*
201   cond_lock is usually same as start_lock. It is needed for the case when
202   start_lock is 0 which happens if start_slave_thread() is called already
203   inside the start_lock section, but at the same time we want a
204   mysql_cond_wait() on start_cond, start_lock
205 */
206 int start_slave_thread(
207 #ifdef HAVE_PSI_INTERFACE
208                        PSI_thread_key thread_key,
209 #endif
210                        pthread_handler h_func,
211                        mysql_mutex_t *start_lock,
212                        mysql_mutex_t *cond_lock,
213                        mysql_cond_t *start_cond,
214                        volatile uint *slave_running,
215                        volatile ulong *slave_run_id,
216                        Master_info *mi);
217 
218 /* If fd is -1, dump to NET */
219 int mysql_table_dump(THD* thd, const char* db,
220 		     const char* tbl_name, int fd = -1);
221 
222 /* retrieve table from master and copy to slave*/
223 int fetch_master_table(THD* thd, const char* db_name, const char* table_name,
224 		       Master_info* mi, MYSQL* mysql, bool overwrite);
225 
226 void show_master_info_get_fields(THD *thd, List<Item> *field_list,
227                                      bool full, size_t gtid_pos_length);
228 bool show_master_info(THD* thd, Master_info* mi, bool full);
229 bool show_all_master_info(THD* thd);
230 void show_binlog_info_get_fields(THD *thd, List<Item> *field_list);
231 bool show_binlog_info(THD* thd);
232 bool rpl_master_has_bug(const Relay_log_info *rli, uint bug_id, bool report,
233                         bool (*pred)(const void *), const void *param);
234 bool rpl_master_erroneous_autoinc(THD* thd);
235 
236 const char *print_slave_db_safe(const char *db);
237 void skip_load_data_infile(NET* net);
238 
239 void slave_prepare_for_shutdown();
240 void end_slave(); /* release slave threads */
241 void close_active_mi(); /* clean up slave threads data */
242 void clear_until_condition(Relay_log_info* rli);
243 void clear_slave_error(Relay_log_info* rli);
244 void end_relay_log_info(Relay_log_info* rli);
245 void init_thread_mask(int* mask,Master_info* mi,bool inverse);
246 Format_description_log_event *
247 read_relay_log_description_event(IO_CACHE *cur_log, ulonglong start_pos,
248                                  const char **errmsg);
249 
250 int init_relay_log_pos(Relay_log_info* rli,const char* log,ulonglong pos,
251 		       bool need_data_lock, const char** errmsg,
252                        bool look_for_description_event);
253 
254 int purge_relay_logs(Relay_log_info* rli, THD *thd, bool just_reset,
255 		     const char** errmsg);
256 void set_slave_thread_options(THD* thd);
257 void set_slave_thread_default_charset(THD *thd, rpl_group_info *rgi);
258 int rotate_relay_log(Master_info* mi);
259 int has_temporary_error(THD *thd);
260 int sql_delay_event(Log_event *ev, THD *thd, rpl_group_info *rgi);
261 int apply_event_and_update_pos(Log_event* ev, THD* thd,
262                                struct rpl_group_info *rgi);
263 int apply_event_and_update_pos_for_parallel(Log_event* ev, THD* thd,
264                                             struct rpl_group_info *rgi);
265 
266 int init_intvar_from_file(int* var, IO_CACHE* f, int default_val);
267 int init_floatvar_from_file(float* var, IO_CACHE* f, float default_val);
268 int init_strvar_from_file(char *var, int max_size, IO_CACHE *f,
269                           const char *default_val);
270 int init_dynarray_intvar_from_file(DYNAMIC_ARRAY* arr, IO_CACHE* f);
271 
272 pthread_handler_t handle_slave_io(void *arg);
273 void slave_output_error_info(rpl_group_info *rgi, THD *thd);
274 pthread_handler_t handle_slave_sql(void *arg);
275 bool net_request_file(NET* net, const char* fname);
276 void slave_background_kill_request(THD *to_kill);
277 void slave_background_gtid_pos_create_request
278         (rpl_slave_state::gtid_pos_table *table_entry);
279 void slave_background_gtid_pending_delete_request(void);
280 
281 extern Master_info *active_mi; /* active_mi for multi-master */
282 extern Master_info *default_master_info; /* To replace active_mi */
283 extern Master_info_index *master_info_index;
284 extern LEX_CSTRING default_master_connection_name;
285 extern my_bool replicate_same_server_id;
286 
287 extern int disconnect_slave_event_count, abort_slave_event_count ;
288 
289 /* the master variables are defaults read from my.cnf or command line */
290 extern uint report_port;
291 extern char *master_info_file, *report_user;
292 extern char *report_host, *report_password;
293 
294 extern I_List<THD> threads;
295 
296 #else
297 #define close_active_mi() /* no-op */
298 #endif /* HAVE_REPLICATION */
299 
300 /* masks for start/stop operations on io and sql slave threads */
301 #define SLAVE_IO  1
302 #define SLAVE_SQL 2
303 
304 /**
305   @} (end of group Replication)
306 */
307 
308 #endif
309