summaryrefslogtreecommitdiff
path: root/sql/events.h
blob: 4b4505b6a02ed4b017c8fcf0004b99a2d835ed47 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
#ifndef _EVENT_H_
#define _EVENT_H_
/* Copyright (c) 2004, 2013, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

/**
  @defgroup Event_Scheduler Event Scheduler
  @ingroup Runtime_Environment
  @{

  @file events.h

  A public interface of Events_Scheduler module.
*/

#ifdef HAVE_PSI_INTERFACE
extern PSI_mutex_key key_event_scheduler_LOCK_scheduler_state;
extern PSI_cond_key key_event_scheduler_COND_state;
extern PSI_thread_key key_thread_event_scheduler, key_thread_event_worker;
#endif /* HAVE_PSI_INTERFACE */

/* Always defined, for SHOW PROCESSLIST. */
extern PSI_stage_info stage_waiting_on_empty_queue;
extern PSI_stage_info stage_waiting_for_next_activation;
extern PSI_stage_info stage_waiting_for_scheduler_to_stop;

#include "sql_string.h"                         /* LEX_CSTRING */
#include "my_time.h"                            /* interval_type */

class Event_db_repository;
class Event_parse_data;
class Event_queue;
class Event_scheduler;
struct TABLE_LIST;
class THD;
typedef class Item COND;

int
sortcmp_lex_string(const LEX_CSTRING *s, const LEX_CSTRING *t,
                   const CHARSET_INFO *cs);

/**
  @brief A facade to the functionality of the Event Scheduler.

  Every public operation against the scheduler has to be executed via the
  interface provided by a static method of this class. No instance of this
  class is ever created and it has no non-static data members.

  The life cycle of the Events module is the following:

  At server start up:
     init_mutexes() -> init()
  When the server is running:
     create_event(), drop_event(), start_or_stop_event_scheduler(), etc
  At shutdown:
     deinit(), destroy_mutexes().

  The peculiar initialization and shutdown cycle is an adaptation to the
  outside server startup/shutdown framework and mimics the rest of MySQL
  subsystems (ACL, time zone tables, etc).
*/

class Events
{
public:
  /*
    the following block is to support --event-scheduler command line option
    and the @@global.event_scheduler SQL variable.
    See sys_var.cc
  */
  enum enum_opt_event_scheduler { EVENTS_OFF, EVENTS_ON, EVENTS_DISABLED,
                                  EVENTS_ORIGINAL };
  /* Protected using LOCK_global_system_variables only. */
  static ulong opt_event_scheduler, startup_state;
  static ulong inited;
  static bool check_if_system_tables_error();
  static bool start(int *err_no);
  static bool stop();

public:
  /* A hack needed for Event_queue_element */
  static Event_db_repository *
  get_db_repository() { return db_repository; }

  static bool init(THD *thd, bool opt_noacl);

  static void
  deinit();

  static void
  init_mutexes();

  static void
  destroy_mutexes();

  static bool
  create_event(THD *thd, Event_parse_data *parse_data);

  static bool
  update_event(THD *thd, Event_parse_data *parse_data,
               LEX_CSTRING *new_dbname, LEX_CSTRING *new_name);

  static bool
  drop_event(THD *thd, const LEX_CSTRING *dbname, const LEX_CSTRING *name,
             bool if_exists);

  static void
  drop_schema_events(THD *thd, const char *db);

  static bool
  show_create_event(THD *thd, const LEX_CSTRING *dbname,
                    const LEX_CSTRING *name);

  /* Needed for both SHOW CREATE EVENT and INFORMATION_SCHEMA */
  static int
  reconstruct_interval_expression(String *buf, interval_type interval,
                                  longlong expression);

  static int
  fill_schema_events(THD *thd, TABLE_LIST *tables, COND * /* cond */);

  static void
  dump_internal_status();

  static void set_original_state(ulong startup_state_org)
  {
    startup_state= startup_state_org;
  }

private:

  static bool
  load_events_from_db(THD *thd);

private:
  static Event_queue         *event_queue;
  static Event_scheduler     *scheduler;
  static Event_db_repository *db_repository;

private:
  /* Prevent use of these */
  Events(const Events &);
  void operator=(Events &);
};

/**
  @} (end of group Event Scheduler)
*/

#endif /* _EVENT_H_ */