1 /* Copyright (c) 2010, 2016, Oracle and/or its affiliates. All rights reserved.
2 
3    This program is free software; you can redistribute it and/or modify
4    it under the terms of the GNU General Public License, version 2.0,
5    as published by the Free Software Foundation.
6 
7    This program is also distributed with certain software (including
8    but not limited to OpenSSL) that is licensed under separate terms,
9    as designated in a particular file or component or in included license
10    documentation.  The authors of MySQL hereby grant you an additional
11    permission to link the program and your derivative works with the
12    separately licensed software that they have included with MySQL.
13 
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License, version 2.0, for more details.
18 
19    You should have received a copy of the GNU General Public License
20    along with this program; if not, write to the Free Software
21    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
22 
23 #ifndef RPL_INFO_H
24 #define RPL_INFO_H
25 
26 #include "my_global.h"
27 #include "mysql_com.h"            // NAME_LEN
28 #include "rpl_info_handler.h"     // Rpl_info_handler
29 #include "rpl_reporting.h"        // Slave_reporting_capability
30 #include "atomic_class.h"         // Atomic_int32
31 
32 
33 #define  CHANNEL_NAME_LENGTH NAME_LEN
34 
35 class Rpl_info : public Slave_reporting_capability
36 {
37 public:
38   virtual ~Rpl_info();
39 
40   /*
41     standard lock acquisition order to avoid deadlocks:
42     run_lock, data_lock, relay_log.LOCK_log, relay_log.LOCK_index
43     run_lock, sleep_lock
44     run_lock, info_thd_lock
45 
46     info_thd_lock is to protect operations on info_thd:
47     - before *reading* info_thd we must hold *either* info_thd_lock or
48       run_lock;
49     - before *writing* we must hold *both* run_lock and info_thd_lock.
50   */
51   mysql_mutex_t data_lock, run_lock, sleep_lock, info_thd_lock;
52   /*
53     start_cond is broadcast when SQL thread is started
54     stop_cond  - when stopped
55     data_cond  - when data protected by data_lock changes
56     sleep_cond - when killed
57 
58     'data_cond' is only being used in class Relay_log_info and not in the
59     class Master_info. So 'data_cond' could be moved to Relay_log_info.
60   */
61   mysql_cond_t data_cond, start_cond, stop_cond, sleep_cond;
62 
63 #ifdef HAVE_PSI_INTERFACE
64   PSI_mutex_key *key_info_run_lock, *key_info_data_lock, *key_info_sleep_lock,
65                 *key_info_thd_lock;
66 
67   PSI_mutex_key *key_info_data_cond, *key_info_start_cond, *key_info_stop_cond,
68                 *key_info_sleep_cond;
69 #endif
70 
71   THD *info_thd;
72 
73   bool inited;
74   volatile bool abort_slave;
75   volatile uint slave_running;
76   volatile ulong slave_run_id;
77 
78 #ifndef DBUG_OFF
79   int events_until_exit;
80 #endif
81 
82   /**
83     Sets the persistency component/handler.
84 
85     @param[in] hanlder Pointer to the handler.
86   */
set_rpl_info_handler(Rpl_info_handler * param_handler)87   void set_rpl_info_handler(Rpl_info_handler * param_handler)
88   {
89     handler= param_handler;
90   }
91 
92   /**
93     Gets the persistency component/handler.
94 
95     @return the handler if there is one.
96   */
get_rpl_info_handler()97   Rpl_info_handler *get_rpl_info_handler()
98   {
99     return (handler);
100   }
101 
check_info()102   enum_return_check check_info()
103   {
104     return (handler->check_info());
105   }
106 
remove_info()107   int remove_info()
108   {
109     return (handler->remove_info());
110   }
111 
clean_info()112   int clean_info()
113   {
114     return (handler->clean_info());
115   }
116 
is_transactional()117   bool is_transactional()
118   {
119     return (handler->is_transactional());
120   }
121 
update_is_transactional()122   bool update_is_transactional()
123   {
124     return (handler->update_is_transactional());
125   }
126 
get_description_info()127   char *get_description_info()
128   {
129     return (handler->get_description_info());
130   }
131 
copy_info(Rpl_info_handler * from,Rpl_info_handler * to)132   bool copy_info(Rpl_info_handler *from, Rpl_info_handler *to)
133   {
134     if (read_info(from) || write_info(to))
135       return(TRUE);
136 
137     return(FALSE);
138   }
139 
get_internal_id()140   uint get_internal_id()
141   {
142     return internal_id;
143   }
144 
get_channel()145   char *get_channel()
146   {
147     return channel;
148   }
149 
150  /**
151    To search in the slave repositories, each slave info object
152    (mi, rli or worker) should use a primary key. This function
153    sets the field values of the slave info objects with
154    the search information, which is nothing but PK in mysql slave
155    info tables.
156    Ex: field_value[23]="channel_name" in the master info
157    object.
158 
159    Currently, used only for TABLE repository.
160 */
161 
162  virtual bool set_info_search_keys(Rpl_info_handler *to)= 0;
163 
164 protected:
165   /**
166     Pointer to the repository's handler.
167   */
168   Rpl_info_handler *handler;
169 
170   /**
171     Uniquely and internaly identifies an info entry (.e.g. a row or
172     file). This information is completely transparent to users and
173     is used only during startup to retrieve information from the
174     repositories.
175 
176     @todo, This is not anymore required for Master_info and
177            Relay_log_info, since Channel can be used to uniquely
178            identify this. To preserve backward compatibility,
179            we keep this for Master_info and Relay_log_info.
180            However, {id, channel} is still required for a worker info.
181   */
182   uint internal_id;
183 
184   /**
185      Every slave info object acts on a particular channel in Multisource
186      Replication.
187   */
188   char channel[CHANNEL_NAME_LENGTH+1];
189 
190   Rpl_info(const char* type
191 #ifdef HAVE_PSI_INTERFACE
192            ,PSI_mutex_key *param_key_info_run_lock,
193            PSI_mutex_key *param_key_info_data_lock,
194            PSI_mutex_key *param_key_info_sleep_lock,
195            PSI_mutex_key *param_key_info_thd_lock,
196            PSI_mutex_key *param_key_info_data_cond,
197            PSI_mutex_key *param_key_info_start_cond,
198            PSI_mutex_key *param_key_info_stop_cond,
199            PSI_mutex_key *param_key_info_sleep_cond
200 #endif
201            ,uint param_id, const char* param_channel
202           );
203 
204 private:
205   virtual bool read_info(Rpl_info_handler *from)= 0;
206   virtual bool write_info(Rpl_info_handler *to)= 0;
207 
208   Rpl_info(const Rpl_info& info);
209   Rpl_info& operator=(const Rpl_info& info);
210 
211 public:
212   /* True when the thread is still running, but started the stop procedure */
213   Atomic_int32 is_stopping;
214 };
215 #endif /* RPL_INFO_H */
216