1/* Copyright (c) 2014, 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 as published by
5 the Free Software Foundation; version 2 of the License.
6
7 This program is distributed in the hope that it will be useful,
8 but WITHOUT ANY WARRANTY; without even the implied warranty of
9 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 GNU General Public License for more details.
11
12 You should have received a copy of the GNU General Public License
13 along with this program; if not, write to the Free Software
14 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
15
16#ifndef SEMISYNC_MASTER_ACK_RECEIVER_DEFINED
17#define SEMISYNC_MASTER_ACK_RECEIVER_DEFINED
18
19#include "my_global.h"
20#include "my_pthread.h"
21#include "sql_class.h"
22#include "semisync.h"
23/**
24 Ack_receiver is responsible to control ack receive thread and maintain
25 slave information used by ack receive thread.
26
27 There are mainly four operations on ack receive thread:
28 start: start ack receive thread
29 stop: stop ack receive thread
30 add_slave: maintain a new semisync slave's information
31 remove_slave: remove a semisync slave's information
32 */
33class Ack_receiver : public Repl_semi_sync_base
34{
35public:
36 Ack_receiver();
37 ~Ack_receiver() {}
38 void cleanup();
39 /**
40 Notify ack receiver to receive acks on the dump session.
41
42 It adds the given dump thread into the slave list and wakes
43 up ack thread if it is waiting for any slave coming.
44
45 @param[in] thd THD of a dump thread.
46
47 @return it return false if succeeds, otherwise true is returned.
48 */
49 bool add_slave(THD *thd);
50
51 /**
52 Notify ack receiver not to receive ack on the dump session.
53
54 it removes the given dump thread from slave list.
55
56 @param[in] thd THD of a dump thread.
57 */
58 void remove_slave(THD *thd);
59
60 /**
61 Start ack receive thread
62
63 @return it return false if succeeds, otherwise true is returned.
64 */
65 bool start();
66
67 /**
68 Stop ack receive thread
69 */
70 void stop();
71
72 /**
73 The core of ack receive thread.
74
75 It monitors all slaves' sockets and receives acks when they come.
76 */
77 void run();
78
79 void set_trace_level(unsigned long trace_level)
80 {
81 m_trace_level= trace_level;
82 }
83private:
84 enum status {ST_UP, ST_DOWN, ST_STOPPING};
85 uint8 m_status;
86 /*
87 Protect m_status, m_slaves_changed and m_slaves. ack thread and other
88 session may access the variables at the same time.
89 */
90 mysql_mutex_t m_mutex;
91 mysql_cond_t m_cond;
92 /* If slave list is updated(add or remove). */
93 bool m_slaves_changed;
94
95 class Slave :public ilink
96 {
97public:
98 THD *thd;
99 Vio vio;
100
101 my_socket sock_fd() { return vio.mysql_socket.fd; }
102 uint server_id() { return thd->variables.server_id; }
103 };
104
105 I_List<Slave> m_slaves;
106
107 pthread_t m_pid;
108
109/* Declare them private, so no one can copy the object. */
110 Ack_receiver(const Ack_receiver &ack_receiver);
111 Ack_receiver& operator=(const Ack_receiver &ack_receiver);
112
113 void set_stage_info(const PSI_stage_info &stage);
114 void wait_for_slave_connection();
115 my_socket get_slave_sockets(fd_set *fds, uint *count);
116};
117
118extern Ack_receiver ack_receiver;
119#endif
120