MySQL 8.2.0
Source Code Documentation
events.h
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1#ifndef _EVENT_H_
2#define _EVENT_H_
3/* Copyright (c) 2004, 2023, Oracle and/or its affiliates.
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License, version 2.0,
7 as published by the Free Software Foundation.
8
9 This program is also distributed with certain software (including
10 but not limited to OpenSSL) that is licensed under separate terms,
11 as designated in a particular file or component or in included license
12 documentation. The authors of MySQL hereby grant you an additional
13 permission to link the program and your derivative works with the
14 separately licensed software that they have included with MySQL.
15
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License, version 2.0, for more details.
20
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
24
25/**
26 @defgroup Event_Scheduler Event Scheduler
27 @ingroup Runtime_Environment
28 @{
29
30 @file sql/events.h
31
32 A public interface of Events_Scheduler module.
33*/
34
35#include <stddef.h>
36#include <sys/types.h>
37
38#include "lex_string.h"
39#include "my_inttypes.h"
40#include "my_psi_config.h"
41#include "my_time.h" /* interval_type */
46#include "sql/psi_memory_key.h"
47
50class Event_queue;
51class Event_scheduler;
52class String;
53class THD;
54
55namespace dd {
56class Schema;
57}
58
59struct CHARSET_INFO;
60
61#ifdef HAVE_PSI_INTERFACE
65#endif /* HAVE_PSI_INTERFACE */
66
67/* Always defined, for SHOW PROCESSLIST. */
71
73
74/**
75 @brief A facade to the functionality of the Event Scheduler.
76
77 Every public operation against the scheduler has to be executed via the
78 interface provided by a static method of this class. No instance of this
79 class is ever created and it has no non-static data members.
80
81 The life cycle of the Events module is the following:
82
83 At server start up:
84 init_mutexes() -> init()
85 When the server is running:
86 create_event(), drop_event(), start_or_stop_event_scheduler(), etc
87 At shutdown:
88 deinit(), destroy_mutexes().
89
90 The peculiar initialization and shutdown cycle is an adaptation to the
91 outside server startup/shutdown framework and mimics the rest of MySQL
92 subsystems (ACL, time zone tables, etc).
93*/
94
95class Events {
96 public:
97 /*
98 the following block is to support --event-scheduler command line option
99 and the @@global.event_scheduler SQL variable.
100 See sys_var.cc
101 */
103 /* Protected using LOCK_global_system_variables only. */
105 static bool start(int *err_no);
106 static bool stop();
107
108 static bool init(bool opt_noacl);
109
110 static void deinit();
111
112 static void init_mutexes();
113
114 static bool create_event(THD *thd, Event_parse_data *parse_data,
115 bool if_exists);
116
117 static bool update_event(THD *thd, Event_parse_data *parse_data,
118 const LEX_CSTRING *new_dbname,
119 const LEX_CSTRING *new_name);
120
121 static bool drop_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name,
122 bool if_exists);
123
124 static bool lock_schema_events(THD *thd, const dd::Schema &schema);
125
126 static bool drop_schema_events(THD *thd, const dd::Schema &schema);
127
128 static bool show_create_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name);
129
130 /* Needed for both SHOW CREATE EVENT and INFORMATION_SCHEMA */
133 longlong expression);
134
135 static void dump_internal_status();
136
137 Events(const Events &) = delete;
138 void operator=(Events &) = delete;
139
140 private:
143};
144
145/**
146 @} (end of group Event Scheduler)
147*/
148
149#endif /* _EVENT_H_ */
Definition: event_db_repository.h:86
Definition: event_parse_data.h:43
Queue of active events awaiting execution.
Definition: event_queue.h:101
Definition: event_scheduler.h:67
A facade to the functionality of the Event Scheduler.
Definition: events.h:95
enum_opt_event_scheduler
Definition: events.h:102
@ EVENTS_ON
Definition: events.h:102
@ EVENTS_OFF
Definition: events.h:102
@ EVENTS_DISABLED
Definition: events.h:102
void operator=(Events &)=delete
Events(const Events &)=delete
Using this class is fraught with peril, and you need to be very careful when doing so.
Definition: sql_string.h:166
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_lexer_thd.h:35
Definition: schema.h:62
static bool update_event(THD *thd, Event_parse_data *parse_data, const LEX_CSTRING *new_dbname, const LEX_CSTRING *new_name)
Alter an event.
Definition: events.cc:479
static bool drop_schema_events(THD *thd, const dd::Schema &schema)
Drops all events from a schema.
Definition: events.cc:763
static Event_queue * event_queue
Definition: events.h:141
PSI_cond_key key_event_scheduler_COND_state
Definition: events.cc:1016
int sortcmp_lex_string(LEX_CSTRING s, LEX_CSTRING t, const CHARSET_INFO *cs)
Definition: events.cc:152
static bool start(int *err_no)
Definition: events.cc:1119
PSI_thread_key key_thread_event_worker
Definition: events.h:64
PSI_thread_key key_thread_event_scheduler
Definition: events.cc:1025
static void deinit()
Definition: events.cc:994
static bool drop_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name, bool if_exists)
Drops an event.
Definition: events.cc:639
static bool lock_schema_events(THD *thd, const dd::Schema &schema)
Take exclusive metadata lock on all events in a schema.
Definition: events.cc:706
static void dump_internal_status()
Definition: events.cc:1098
static bool create_event(THD *thd, Event_parse_data *parse_data, bool if_exists)
Create a new event.
Definition: events.cc:334
static void init_mutexes()
Definition: events.cc:1082
PSI_stage_info stage_waiting_on_empty_queue
Definition: events.cc:1034
static ulong opt_event_scheduler
Definition: events.h:104
static bool init(bool opt_noacl)
Initializes the scheduler's structures.
Definition: events.cc:915
static bool show_create_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name)
Implement SHOW CREATE EVENT statement.
Definition: events.cc:855
static bool stop()
Definition: events.cc:1125
static Event_scheduler * scheduler
Definition: events.h:142
PSI_mutex_key key_event_scheduler_LOCK_scheduler_state
Definition: events.cc:1006
PSI_stage_info stage_waiting_for_next_activation
Definition: events.cc:1036
PSI_stage_info stage_waiting_for_scheduler_to_stop
Definition: events.cc:1038
static int reconstruct_interval_expression(String *buf, interval_type interval, longlong expression)
Definition: events.cc:175
unsigned int PSI_cond_key
Instrumented cond key.
Definition: psi_cond_bits.h:43
unsigned int PSI_mutex_key
Instrumented mutex key.
Definition: psi_mutex_bits.h:51
unsigned int PSI_thread_key
Instrumented thread key.
Definition: psi_thread_bits.h:49
Some integer typedefs for easier portability.
long long int longlong
Definition: my_inttypes.h:54
Defines various enable/disable and HAVE_ macros related to the performance schema instrumentation sys...
Interface for low level time utilities.
interval_type
Available interval types used in any statement.
Definition: my_time.h:454
static int interval
Definition: mysqladmin.cc:69
bool opt_noacl
Definition: mysqld.cc:1307
Definition: buf0block_hint.cc:29
borrowable::session_track::Schema< true > Schema
Definition: classic_protocol_session_track.h:288
Definition: commit_order_queue.h:33
The version of the current data dictionary table definitions.
Definition: dictionary_client.h:42
Performance schema instrumentation interface.
Instrumentation helpers for mutexes.
Performance schema instrumentation interface.
Performance schema instrumentation interface.
case opt name
Definition: sslopt-case.h:32
Definition: m_ctype.h:422
Definition: mysql_lex_string.h:39
Stage instrument information.
Definition: psi_stage_bits.h:73