MySQL  8.0.18
Source Code Documentation
events.h
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1 #ifndef _EVENT_H_
2 #define _EVENT_H_
3 /* Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
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 "mysql/psi/psi_memory.h" // PSI_memory_key
47 
49 class Event_parse_data;
50 class Event_queue;
51 class Event_scheduler;
52 class String;
53 class THD;
54 
55 namespace dd {
56 class Schema;
57 }
58 
59 struct CHARSET_INFO;
60 
61 #ifdef HAVE_PSI_INTERFACE
65 #endif /* HAVE_PSI_INTERFACE */
66 
68 
69 /* Always defined, for SHOW PROCESSLIST. */
73 
75 
76 /**
77  @brief A facade to the functionality of the Event Scheduler.
78 
79  Every public operation against the scheduler has to be executed via the
80  interface provided by a static method of this class. No instance of this
81  class is ever created and it has no non-static data members.
82 
83  The life cycle of the Events module is the following:
84 
85  At server start up:
86  init_mutexes() -> init()
87  When the server is running:
88  create_event(), drop_event(), start_or_stop_event_scheduler(), etc
89  At shutdown:
90  deinit(), destroy_mutexes().
91 
92  The peculiar initialization and shutdown cycle is an adaptation to the
93  outside server startup/shutdown framework and mimics the rest of MySQL
94  subsystems (ACL, time zone tables, etc).
95 */
96 
97 class Events {
98  public:
99  /*
100  the following block is to support --event-scheduler command line option
101  and the @@global.event_scheduler SQL variable.
102  See sys_var.cc
103  */
105  /* Protected using LOCK_global_system_variables only. */
107  static bool start(int *err_no);
108  static bool stop();
109 
110  static bool init(bool opt_noacl);
111 
112  static void deinit();
113 
114  static void init_mutexes();
115 
116  static bool create_event(THD *thd, Event_parse_data *parse_data,
117  bool if_exists);
118 
119  static bool update_event(THD *thd, Event_parse_data *parse_data,
120  const LEX_CSTRING *new_dbname,
121  const LEX_CSTRING *new_name);
122 
123  static bool drop_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name,
124  bool if_exists);
125 
126  static bool lock_schema_events(THD *thd, const dd::Schema &schema);
127 
128  static bool drop_schema_events(THD *thd, const dd::Schema &schema);
129 
130  static bool show_create_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name);
131 
132  /* Needed for both SHOW CREATE EVENT and INFORMATION_SCHEMA */
133  static int reconstruct_interval_expression(String *buf,
135  longlong expression);
136 
137  static void dump_internal_status();
138 
139  Events(const Events &) = delete;
140  void operator=(Events &) = delete;
141 
142  private:
145 };
146 
147 /**
148  @} (end of group Event Scheduler)
149 */
150 
151 #endif /* _EVENT_H_ */
static bool lock_schema_events(THD *thd, const dd::Schema &schema)
Take exclusive metadata lock on all events in a schema.
Definition: events.cc:693
static int interval
Definition: mysqladmin.cc:64
A facade to the functionality of the Event Scheduler.
Definition: events.h:97
Events(const Events &)=delete
int sortcmp_lex_string(LEX_CSTRING s, LEX_CSTRING t, CHARSET_INFO *cs)
Definition: events.cc:150
const string name("\ame\)
Some integer typedefs for easier portability.
static void dump_internal_status()
Definition: events.cc:1075
static bool start(int *err_no)
Definition: events.cc:1096
Definition: mysql_lex_string.h:39
void operator=(Events &)=delete
PSI_stage_info stage_waiting_on_empty_queue
Definition: events.cc:1012
Performance schema instrumentation interface.
unsigned int PSI_memory_key
Instrumented memory key.
Definition: psi_memory_bits.h:46
static void init_mutexes()
Definition: events.cc:1059
Using this class is fraught with peril, and you need to be very careful when doing so...
Definition: sql_string.h:161
static bool show_create_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name)
Implement SHOW CREATE EVENT statement.
Definition: events.cc:835
unsigned int PSI_mutex_key
Instrumented mutex key.
Definition: psi_mutex_bits.h:49
Definition: events.h:104
static Event_scheduler * scheduler
Definition: events.h:144
unsigned int PSI_cond_key
Instrumented cond key.
Definition: psi_cond_bits.h:41
interval_type
Available interval types used in any statement.
Definition: my_time.h:384
enum_opt_event_scheduler
Definition: events.h:104
PSI_thread_key key_thread_event_worker
Definition: events.cc:1004
Stage instrument information.
Definition: psi_stage_bits.h:71
Performance schema instrumentation interface.
PSI_mutex_key key_event_scheduler_LOCK_scheduler_state
Definition: events.cc:985
Definition: event_parse_data.h:43
static Event_queue * event_queue
Definition: events.h:143
Defines various enable/disable and HAVE_ macros related to the performance schema instrumentation sys...
static bool drop_schema_events(THD *thd, const dd::Schema &schema)
Drops all events from a schema.
Definition: events.cc:743
long long int longlong
Definition: my_inttypes.h:54
Definition: events.h:104
PSI_cond_key key_event_scheduler_COND_state
Definition: events.cc:995
Definition: m_ctype.h:359
Instrumentation helpers for mutexes.
Definition: events.h:104
Queue of active events awaiting execution.
Definition: event_queue.h:101
static bool create_event(THD *thd, Event_parse_data *parse_data, bool if_exists)
Create a new event.
Definition: events.cc:332
static bool stop()
Definition: events.cc:1102
PSI_stage_info stage_waiting_for_scheduler_to_stop
Definition: events.cc:1016
Performance schema instrumentation interface.
unsigned int PSI_thread_key
Instrumented thread key.
Definition: psi_thread_bits.h:48
Definition: event_scheduler.h:67
Performance schema instrumentation interface.
static ulong opt_event_scheduler
Definition: events.h:106
static bool drop_event(THD *thd, LEX_CSTRING dbname, LEX_CSTRING name, bool if_exists)
Drops an event.
Definition: events.cc:627
static void deinit()
Definition: events.cc:973
Definition: event_db_repository.h:88
static int reconstruct_interval_expression(String *buf, interval_type interval, longlong expression)
Definition: events.cc:173
Definition: schema.h:61
The version of the current data dictionary table definitions.
Definition: dictionary_client.h:39
Interface for low level time utilities.
PSI_stage_info stage_waiting_for_next_activation
Definition: events.cc:1014
PSI_thread_key key_thread_event_scheduler
Definition: events.cc:1004
unsigned long ulong
Definition: my_inttypes.h:48
static bool init(bool opt_noacl)
Initializes the scheduler&#39;s structures.
Definition: events.cc:894
PSI_memory_key key_memory_event_basic_root
Definition: events.cc:1019
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:476
For each client connection we create a separate thread with THD serving as a thread/connection descri...
Definition: sql_class.h:778
bool opt_noacl
Definition: mysqld.cc:1092