WL#3337 (Event scheduler new architecture)

This is a post-review patch.

Fixes the typelib implementation, available only in 5.1.11.

--event-scheduler cmdline : DISABLED | ON | OFF | 0 | 1
DISABLED - makes the scheduler unavailable during the server run
(ON|1)-  When the server is started the scheduler will be started. It can
         be stopped and restarted by setting appropriate values to
         GLOBAL event_scheduler
(OFF|0)- When the server is started, the scheduler won't be started. It
         can be started and again stopped by setting appropriate values to
         GLOBAL event_scheduler. _DEFAULT_ value

The GLOBAL variable event_scheduler can have the following values:
OFF | ON | 0 | 1
DISABLED is not possible and every attempt will end with an error that
it's not a valid value for the variable.
OFF | 0 - This is the pre-5.1.11 behavior - The scheduler stops, if not
          already stopped, and can be started again  by setting
          the value of the variable to ON|1.
ON | 1  - This is the pre-5.1.11 behavior - The scheduler starts, if not
          already started, and can be stopped again by setting the value
          of the variable to OFF|0.


mysql-test/r/events.result:
  update result
mysql-test/r/events_bugs.result:
  update result
mysql-test/r/events_logs_tests.result:
  update result
mysql-test/r/events_restart_phase1.result:
  update result
mysql-test/r/events_restart_phase3.result:
  update result
mysql-test/r/events_scheduling.result:
  update result
mysql-test/r/events_stress.result:
  update result
mysql-test/t/events.test:
  update test:
  2 -> off
  1 -> on
mysql-test/t/events_bugs.test:
  update test:
  2 -> off
  1 -> on
mysql-test/t/events_logs_tests.test:
  update test:
  2 -> off
  1 -> on
mysql-test/t/events_restart_phase1.test:
  update test:
  2 -> off
  1 -> on
mysql-test/t/events_restart_phase2-master.opt:
  update master file : 1 => on
mysql-test/t/events_scheduling.test:
  update test:
  2 -> off
  1 -> on
  
  add tests for event_scheduler global variable representation from
  SHOW VARIABLES.
mysql-test/t/events_stress.test:
  update test:
  2 -> off
  1 -> on
sql/events.cc:
  Implement two different TYPELIBs for --event-scheduler cmd line
  option and for GLOBAL variable event_scheduler
  
  --event-scheduler cmdline : DISABLED | ON | OFF | 0 | 1
  DISABLED - makes the scheduler unavailable during the server run
  (ON|1)-  When the server is started the scheduler will be started. It can
           be stopped and restarted by setting appropriate values to
           GLOBAL event_scheduler
  (OFF|0)- When the server is started, the scheduler won't be started. It
           can be started and again stopped by setting appropriate values to
           GLOBAL event_scheduler. _DEFAULT_ value
  
  The GLOBAL variable event_scheduler can have the following values:
  OFF | ON | 0 | 1
  DISABLED is not possible and every attempt will end with an error that
  it's not a valid value for the variable.
  OFF | 0 - This is the pre-5.1.11 behavior - The scheduler stops, if not
            already stopped, and can be started again  by setting
            the value of the variable to ON|1.
  ON | 1  - This is the pre-5.1.11 behavior - The scheduler starts, if not
            already started, and can be stopped again by setting the value
            of the variable to OFF|0.
sql/events.h:
  additional TYPELIB for GLOBAL event_scheduler
sql/mysqld.cc:
  --event-scheduler should be checked against a TYPELIB and
  therefore should be GET_STR, as well as we make the parameter optional.
  When not provided OFF|0 is used.
sql/set_var.cc:
  Implement typelib for event_scheduler variable.
  If allows both INT_RESULT -> 0 | 1 
  and STRING_RESULT -> OFF | ON
  The variable is shown as DISABLED | ON | OFF
sql/set_var.h:
  Implement typelib, which expects both STRING and INT,
  for event_scheduler.

19 files changed, 225 insertions, 97 deletions

diff --git a/mysql-test/r/events.result b/mysql-test/r/events.result
index 05b6ff03786..f19c44462c3 100644
--- a/mysql-test/r/events.result
+++ b/mysql-test/r/events.result
@@ -17,13 +17,13 @@ db_x
 SHOW TABLES FROM db_x;
 Tables_in_db_x
 x_table
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 DROP EVENT e_x1;
 DROP EVENT e_x2;
 DROP DATABASE db_x;
 DROP USER pauline@localhost;
 USE events_test;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 drop event if exists event1;
 Warnings:
 Note	1305	Event event1 does not exist
@@ -94,7 +94,7 @@ begin
 alter event e_43 on schedule every 5 minute;
 insert into test_nested values(1);
 end|
-set global event_scheduler = 1;
+set global event_scheduler = on;
 select db, name, body, status, interval_field, interval_value from mysql.event;
 db	name	body	status	interval_field	interval_value
 events_test	e_43	begin
@@ -113,7 +113,7 @@ drop event non_qualif_ev;
 drop table non_qualif;
 alter event non_existant rename to non_existant_too;
 ERROR HY000: Unknown event 'non_existant'
-set global event_scheduler = 2;
+set global event_scheduler = off;
 create event existant on schedule at now() + interval 1 year do select 12;
 alter event non_existant rename to existant;
 ERROR HY000: Event 'existant' already exists
@@ -315,12 +315,14 @@ ERROR HY000: Incorrect AT value: 'definitely not a datetime'
 set names utf8;
 create event задачка on schedule every 123 minute starts now() ends now() + interval 1 month do select 1;
 drop event задачка;
-set event_scheduler=2;
+set event_scheduler=off;
 ERROR HY000: Variable 'event_scheduler' is a GLOBAL variable and should be set with SET GLOBAL
 set global event_scheduler=3;
 ERROR 42000: Variable 'event_scheduler' can't be set to the value of '3'
+set global event_scheduler=disabled;
+ERROR 42000: Variable 'event_scheduler' can't be set to the value of 'disabled'
 "DISABLE the scheduler. Testing that it does not work when the variable is 0"
-set global event_scheduler=2;
+set global event_scheduler=off;
 select definer, name, db from mysql.event;
 definer	name	db
 select get_lock("test_lock1", 20);
@@ -343,7 +345,7 @@ select count(*) from mysql.event;
 count(*)
 0
 "ENABLE the scheduler and get a lock"
-set global event_scheduler=1;
+set global event_scheduler=on;
 select get_lock("test_lock2", 20);
 get_lock("test_lock2", 20)
 1
@@ -371,7 +373,7 @@ select /*3*/ user, host, db, command, state, info from information_schema.proces
 user	host	db	command	state	info
 event_scheduler	localhost	NULL	Daemon	Waiting for next activation	NULL
 root	localhost	events_test	Connect	User lock	select get_lock("test_lock2_1", 20)
-set global event_scheduler=2;
+set global event_scheduler=off;
 "Should have only our process now:"
 select /*4*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
 user	host	db	command	state	info
diff --git a/mysql-test/r/events_bugs.result b/mysql-test/r/events_bugs.result
index 38f3eb37902..4ac1cfc413b 100644
--- a/mysql-test/r/events_bugs.result
+++ b/mysql-test/r/events_bugs.result
@@ -36,9 +36,9 @@ create event e_55 on schedule at 20200101000000 starts 10000101000000 ends 10000
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'starts 10000101000000 ends 10000101000000 do drop table t' at line 1
 create event e_55 on schedule every 10 hour starts 10000101000000 do drop table t;
 ERROR HY000: Incorrect STARTS value: '10000101000000'
-set global event_scheduler=2;
+set global event_scheduler=off;
 delete from mysql.event;
-set global event_scheduler= 1;
+set global event_scheduler= on;
 set @old_sql_mode:=@@sql_mode;
 set sql_mode=ansi;
 select get_lock('test_bug16407', 60);
@@ -57,7 +57,7 @@ root	localhost	events_test	select get_lock('test_bug16407', 60)
 select release_lock('test_bug16407');
 release_lock('test_bug16407')
 1
-set global event_scheduler= 2;
+set global event_scheduler= off;
 select event_schema, event_name, sql_mode from information_schema.events order by event_schema, event_name;
 event_schema	event_name	sql_mode
 events_test	e_16407	REAL_AS_FLOAT,PIPES_AS_CONCAT,ANSI_QUOTES,IGNORE_SPACE,ANSI
@@ -118,7 +118,7 @@ release_lock('ee_16407_2')
 select /*3*/ user, host, db, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
 user	host	db	info
 event_scheduler	localhost	NULL	NULL
-set global event_scheduler= 2;
+set global event_scheduler= off;
 select * from events_smode_test order by ev_name, a;
 ev_name	a
 ee_16407_3	1980-02-19
@@ -139,7 +139,7 @@ set sql_mode='ansi';
 select get_lock('ee_16407_5', 60);
 get_lock('ee_16407_5', 60)
 1
-set global event_scheduler= 1;
+set global event_scheduler= on;
 set sql_mode='traditional';
 create procedure ee_16407_5_pendant() begin insert into events_test.events_smode_test values('ee_16407_5','2001-02-29'); end|
 create procedure ee_16407_6_pendant() begin insert into events_test.events_smode_test values('ee_16407_6','2004-02-29'); end|
@@ -180,10 +180,10 @@ drop event ee_16407_5;
 drop event ee_16407_6;
 drop procedure ee_16407_5_pendant;
 drop procedure ee_16407_6_pendant;
-set global event_scheduler= 2;
+set global event_scheduler= off;
 drop table events_smode_test;
 set sql_mode=@old_sql_mode;
-set global event_scheduler=2;
+set global event_scheduler=off;
 delete from mysql.user where User like 'mysqltest_%';
 delete from mysql.db where User like 'mysqltest_%';
 flush privileges;
diff --git a/mysql-test/r/events_logs_tests.result b/mysql-test/r/events_logs_tests.result
index 5971dead3c8..335ca848387 100644
--- a/mysql-test/r/events_logs_tests.result
+++ b/mysql-test/r/events_logs_tests.result
@@ -14,7 +14,7 @@ USER_HOST	CREATE procedure select_general_log()
 BEGIN
 SELECT user_host, argument FROM mysql.general_log WHERE argument LIKE '%alabala%';
 END
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 TRUNCATE mysql.general_log;
 CREATE EVENT log_general ON SCHEDULE EVERY 1 MINUTE DO SELECT 'alabala', SLEEP(1) FROM DUAL;
 "Wait the scheduler to start"
@@ -25,7 +25,7 @@ USER_HOST	CREATE EVENT log_general ON SCHEDULE EVERY 1 MINUTE DO SELECT 'alabala
 USER_HOST	SELECT 'alabala', SLEEP(1) FROM DUAL
 DROP PROCEDURE select_general_log;
 DROP EVENT log_general;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 "Check slow query log"
 "Save the values"
 SET @old_global_long_query_time:=(select get_value());
@@ -58,12 +58,12 @@ SET SESSION long_query_time=1;
 SELECT * FROM slow_event_test;
 slo_val	val
 SET SESSION long_query_time=1;
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 CREATE EVENT long_event ON SCHEDULE EVERY 1 MINUTE DO INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(1.5);
 "Sleep some more time than the actual event run will take"
 SHOW VARIABLES LIKE 'event_scheduler';
 Variable_name	Value
-event_scheduler	1
+event_scheduler	ON
 "Check our table. Should see 1 row"
 SELECT * FROM slow_event_test;
 slo_val	val
diff --git a/mysql-test/r/events_restart_phase1.result b/mysql-test/r/events_restart_phase1.result
index cf0a24c267d..a7a46fa0ab1 100644
--- a/mysql-test/r/events_restart_phase1.result
+++ b/mysql-test/r/events_restart_phase1.result
@@ -1,10 +1,12 @@
 create database if not exists mysqltest_events_test;
 use mysqltest_events_test;
-set global event_scheduler=2;
+set global event_scheduler=off;
 create table execution_log(name char(10));
 create event abc1 on schedule every 1 second do insert into execution_log value('abc1');
 create event abc2 on schedule every 1 second do insert into execution_log value('abc2');
 create event abc3 on schedule every 1 second do insert into execution_log value('abc3');
+select name from execution_log;
+name
 insert into mysql.event values ('db1','bad','select 42','root@localhost',NULL,1000,'MICROSECOND','2006-05-05 17:39:11','2006-05-05 17:39:20','2016-05-05 15:39:24','2016-05-05 15:39:11',NULL,'ENABLED','DROP','','comment1');
 insert into mysql.event values ('db1','bad2','sect','root@localhost',NULL,1000,'SECOND','2006-05-05 17:39:11','2006-05-05 17:39:20','2016-05-05 15:39:24','2016-05-05 15:39:11',NULL,'ENABLED','DROP','','comment2');
 "Now we restart the server"
diff --git a/mysql-test/r/events_restart_phase3.result b/mysql-test/r/events_restart_phase3.result
index 398a9d06546..e653d6a7c23 100644
--- a/mysql-test/r/events_restart_phase3.result
+++ b/mysql-test/r/events_restart_phase3.result
@@ -2,6 +2,9 @@ use mysqltest_events_test;
 "Should get 3 rows : abc1, abc2, abc3
 select distinct name from execution_log order by name;
 name
+abc1
+abc2
+abc3
 drop event abc1;
 drop event abc2;
 drop event abc3;
diff --git a/mysql-test/r/events_scheduling.result b/mysql-test/r/events_scheduling.result
index a068f7f19bc..180c2e4883d 100644
--- a/mysql-test/r/events_scheduling.result
+++ b/mysql-test/r/events_scheduling.result
@@ -1,11 +1,47 @@
 CREATE DATABASE IF NOT EXISTS events_test;
 USE events_test;
+SET GLOBAL event_scheduler=OFF;
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	OFF
+SET GLOBAL event_scheduler=1;
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+SET GLOBAL event_scheduler=0;
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	OFF
+SET GLOBAL event_scheduler=ON;
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+SET GLOBAL event_scheduler=DISABLED;
+ERROR 42000: Variable 'event_scheduler' can't be set to the value of 'DISABLED'
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+SET GLOBAL event_scheduler=-1;
+ERROR 42000: Variable 'event_scheduler' can't be set to the value of '-1'
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+SET GLOBAL event_scheduler=2;
+ERROR 42000: Variable 'event_scheduler' can't be set to the value of '2'
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
+SET GLOBAL event_scheduler=5;
+ERROR 42000: Variable 'event_scheduler' can't be set to the value of '5'
+SHOW VARIABLES LIKE 'event_scheduler';
+Variable_name	Value
+event_scheduler	ON
 CREATE TABLE table_1(a int);
 CREATE TABLE table_2(a int);
 CREATE TABLE table_3(a int);
 CREATE TABLE table_4(a int);
 CREATE TABLE T19170(s1 TIMESTAMP);
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=ON;
 CREATE EVENT two_sec ON SCHEDULE EVERY 2 SECOND DO INSERT INTO table_1 VALUES(1);
 CREATE EVENT start_n_end
 ON SCHEDULE EVERY 1 SECOND
diff --git a/mysql-test/r/events_stress.result b/mysql-test/r/events_stress.result
index 050fe324426..17eb32b36b7 100644
--- a/mysql-test/r/events_stress.result
+++ b/mysql-test/r/events_stress.result
@@ -32,15 +32,15 @@ USE events_conn1_test2;
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test2';
 COUNT(*)
 50
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 DROP DATABASE events_conn1_test2;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test2';
 COUNT(*)
 0
 CREATE DATABASE events_conn1_test3;
 USE events_conn1_test3;
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test3';
 COUNT(*)
 50
@@ -55,9 +55,9 @@ DROP DATABASE events_conn2_db;
 DROP DATABASE events_conn3_db;
 DROP DATABASE events_conn1_test2;
 DROP DATABASE events_conn1_test3;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 DROP DATABASE events_conn1_test4;
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 USE events_test;
 DROP TABLE fill_it1;
 DROP TABLE fill_it2;
diff --git a/mysql-test/t/events.test b/mysql-test/t/events.test
index 161f4c1aefe..75b80c2c452 100644
--- a/mysql-test/t/events.test
+++ b/mysql-test/t/events.test
@@ -21,7 +21,7 @@ SET GLOBAL event_scheduler=1;
 --sleep 1.2
 SHOW DATABASES LIKE 'db_x';
 SHOW TABLES FROM db_x;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 connection priv_conn;
 DROP EVENT e_x1;
 DROP EVENT e_x2;
@@ -33,7 +33,7 @@ USE events_test;
 #
 # END:    BUG #17289 Events: missing privilege check for drop database
 #
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 drop event if exists event1;
 create event event1 on schedule every 15 minute starts now() ends date_add(now(), interval 5 hour) DO begin end;
 alter event event1 rename to event2 enable;
@@ -92,7 +92,7 @@ begin
   insert into test_nested values(1);
 end|
 delimiter ;|
-set global event_scheduler = 1;
+set global event_scheduler = on;
 --sleep 3
 select db, name, body, status, interval_field, interval_value from mysql.event;
 drop event e_43;
@@ -109,7 +109,7 @@ drop table non_qualif;
 --error ER_EVENT_DOES_NOT_EXIST
 alter event non_existant rename to non_existant_too;
 
-set global event_scheduler = 2;
+set global event_scheduler = off;
 create event existant on schedule at now() + interval 1 year do select 12;
 --error ER_EVENT_ALREADY_EXISTS
 alter event non_existant rename to existant;
@@ -279,13 +279,15 @@ drop event задачка;
 
 # event_scheduler is a global var
 --error ER_GLOBAL_VARIABLE
-set event_scheduler=2;
+set event_scheduler=off;
 # event_scheduler could be only either 1 or 2
 --error ER_WRONG_VALUE_FOR_VAR
 set global event_scheduler=3;
+--error ER_WRONG_VALUE_FOR_VAR
+set global event_scheduler=disabled;
 
 --echo "DISABLE the scheduler. Testing that it does not work when the variable is 0"
-set global event_scheduler=2;
+set global event_scheduler=off;
 select definer, name, db from mysql.event;
 select get_lock("test_lock1", 20);
 create event закачка on schedule every 10 hour do select get_lock("test_lock1", 20);
@@ -303,7 +305,7 @@ select count(*) from mysql.event;
 #
 #
 --echo "ENABLE the scheduler and get a lock"
-set global event_scheduler=1;
+set global event_scheduler=on;
 select get_lock("test_lock2", 20);
 --echo "Create an event which tries to acquire a mutex. The event locks on the mutex"
 create event закачка on schedule every 10 hour do select get_lock("test_lock2", 20);
@@ -329,7 +331,7 @@ create event закачка21 on schedule every 10 hour do select get_lock("test
 --sleep 1
 --echo "Should have only 3 processes: the scheduler, our conn and the locked event"
 select /*3*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
-set global event_scheduler=2;
+set global event_scheduler=off;
 --sleep 0.8
 --echo "Should have only our process now:"
 select /*4*/ user, host, db, command, state, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
@@ -396,7 +398,7 @@ drop event e1;
 ##drop event закачка4;
 ##select release_lock("test_lock4");
 
-##set global event_scheduler=2;
+##set global event_scheduler=off;
 ##select sleep(2);
 ##--replace_column 1 # 6 #
 ##show processlist;
diff --git a/mysql-test/t/events_bugs.test b/mysql-test/t/events_bugs.test
index 1fcf527c2fc..04c6d8e91f5 100644
--- a/mysql-test/t/events_bugs.test
+++ b/mysql-test/t/events_bugs.test
@@ -65,9 +65,9 @@ create event e_55 on schedule every 10 hour starts 10000101000000 do drop table
 #
 # Start - 16407: Events: Changes in sql_mode won't be taken into account
 #
-set global event_scheduler=2;
+set global event_scheduler=off;
 delete from mysql.event;
-set global event_scheduler= 1;
+set global event_scheduler= on;
 set @old_sql_mode:=@@sql_mode;
 set sql_mode=ansi;
 select get_lock('test_bug16407', 60);
@@ -83,7 +83,7 @@ delimiter ;|
 select /*1*/ user, host, db, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
 select release_lock('test_bug16407');
 
-set global event_scheduler= 2;
+set global event_scheduler= off;
 
 select event_schema, event_name, sql_mode from information_schema.events order by event_schema, event_name;
 --echo "Let's check whether we change the sql_mode on ALTER EVENT"
@@ -132,7 +132,7 @@ select /*2*/ user, host, db, info from information_schema.processlist where info
 select release_lock('ee_16407_2');
 --sleep 1.2
 select /*3*/ user, host, db, info from information_schema.processlist where info is null or info not like '%processlist%' order by info;
-set global event_scheduler= 2;
+set global event_scheduler= off;
 select * from events_smode_test order by ev_name, a;
 --echo "OK, last check before we drop them"
 select event_schema, event_name, sql_mode from information_schema.events order by event_schema, event_name;
@@ -146,7 +146,7 @@ delete from events_smode_test;
 set sql_mode='ansi';
 select get_lock('ee_16407_5', 60);
 
-set global event_scheduler= 1;
+set global event_scheduler= on;
 
 set sql_mode='traditional';
 delimiter |;
@@ -179,7 +179,7 @@ drop event ee_16407_5;
 drop event ee_16407_6;
 drop procedure ee_16407_5_pendant;
 drop procedure ee_16407_6_pendant;
-set global event_scheduler= 2;
+set global event_scheduler= off;
 drop table events_smode_test;
 set sql_mode=@old_sql_mode;
 #
@@ -189,7 +189,7 @@ set sql_mode=@old_sql_mode;
 #
 # START - 18897: Events: unauthorized action possible with alter event rename
 #
-set global event_scheduler=2;
+set global event_scheduler=off;
 --disable_warnings
 delete from mysql.user where User like 'mysqltest_%';
 delete from mysql.db where User like 'mysqltest_%';
diff --git a/mysql-test/t/events_logs_tests.test b/mysql-test/t/events_logs_tests.test
index 62c2aedf6cc..aee16595ef9 100644
--- a/mysql-test/t/events_logs_tests.test
+++ b/mysql-test/t/events_logs_tests.test
@@ -15,7 +15,7 @@ delimiter ;|
 --echo "Check General Query Log"
 --replace_column 1 USER_HOST
 CALL select_general_log();
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 TRUNCATE mysql.general_log;
 CREATE EVENT log_general ON SCHEDULE EVERY 1 MINUTE DO SELECT 'alabala', SLEEP(1) FROM DUAL;
 --echo "Wait the scheduler to start"
@@ -25,7 +25,7 @@ CREATE EVENT log_general ON SCHEDULE EVERY 1 MINUTE DO SELECT 'alabala', SLEEP(1
 CALL select_general_log();
 DROP PROCEDURE select_general_log;
 DROP EVENT log_general;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 
 --echo "Check slow query log"
 --disable_query_log
@@ -71,7 +71,7 @@ SET SESSION long_query_time=1;
 --echo "This won't go to the slow log"
 SELECT * FROM slow_event_test;
 SET SESSION long_query_time=1;
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 CREATE EVENT long_event ON SCHEDULE EVERY 1 MINUTE DO INSERT INTO slow_event_test SELECT @@long_query_time, SLEEP(1.5);
 --echo "Sleep some more time than the actual event run will take"
 --sleep 2
diff --git a/mysql-test/t/events_restart_phase1.test b/mysql-test/t/events_restart_phase1.test
index 879591e6141..92783ddaef7 100644
--- a/mysql-test/t/events_restart_phase1.test
+++ b/mysql-test/t/events_restart_phase1.test
@@ -6,11 +6,13 @@ create database if not exists mysqltest_events_test;
 --enable_warnings
 
 use mysqltest_events_test;
-set global event_scheduler=2;
+set global event_scheduler=off;
 create table execution_log(name char(10));
 create event abc1 on schedule every 1 second do insert into execution_log value('abc1');
 create event abc2 on schedule every 1 second do insert into execution_log value('abc2');
 create event abc3 on schedule every 1 second do insert into execution_log value('abc3');
+--sleep 1.5
+select name from execution_log;
 
 insert into mysql.event values ('db1','bad','select 42','root@localhost',NULL,1000,'MICROSECOND','2006-05-05 17:39:11','2006-05-05 17:39:20','2016-05-05 15:39:24','2016-05-05 15:39:11',NULL,'ENABLED','DROP','','comment1');
 insert into mysql.event values ('db1','bad2','sect','root@localhost',NULL,1000,'SECOND','2006-05-05 17:39:11','2006-05-05 17:39:20','2016-05-05 15:39:24','2016-05-05 15:39:11',NULL,'ENABLED','DROP','','comment2');
diff --git a/mysql-test/t/events_restart_phase2-master.opt b/mysql-test/t/events_restart_phase2-master.opt
index 656b9e1b017..673e87f4357 100644
--- a/mysql-test/t/events_restart_phase2-master.opt
+++ b/mysql-test/t/events_restart_phase2-master.opt
@@ -1 +1 @@
---event-scheduler=1
+--event-scheduler=on
diff --git a/mysql-test/t/events_scheduling.test b/mysql-test/t/events_scheduling.test
index 7a7502fab7e..0002cf9f29f 100644
--- a/mysql-test/t/events_scheduling.test
+++ b/mysql-test/t/events_scheduling.test
@@ -4,12 +4,34 @@
 
 CREATE DATABASE IF NOT EXISTS events_test;
 USE events_test;
+
+SET GLOBAL event_scheduler=OFF;
+SHOW VARIABLES LIKE 'event_scheduler';
+SET GLOBAL event_scheduler=1;
+SHOW VARIABLES LIKE 'event_scheduler';
+SET GLOBAL event_scheduler=0;
+SHOW VARIABLES LIKE 'event_scheduler';
+SET GLOBAL event_scheduler=ON;
+SHOW VARIABLES LIKE 'event_scheduler';
+--error ER_WRONG_VALUE_FOR_VAR
+SET GLOBAL event_scheduler=DISABLED;
+SHOW VARIABLES LIKE 'event_scheduler';
+--error ER_WRONG_VALUE_FOR_VAR
+SET GLOBAL event_scheduler=-1;
+SHOW VARIABLES LIKE 'event_scheduler';
+--error ER_WRONG_VALUE_FOR_VAR
+SET GLOBAL event_scheduler=2;
+SHOW VARIABLES LIKE 'event_scheduler';
+--error ER_WRONG_VALUE_FOR_VAR
+SET GLOBAL event_scheduler=5;
+SHOW VARIABLES LIKE 'event_scheduler';
+
 CREATE TABLE table_1(a int);
 CREATE TABLE table_2(a int);
 CREATE TABLE table_3(a int);
 CREATE TABLE table_4(a int);
 CREATE TABLE T19170(s1 TIMESTAMP);
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=ON;
 # We need to have 2 to make it safe with valgrind. This is probably because
 # of when we calculate the timestamp value
 CREATE EVENT two_sec ON SCHEDULE EVERY 2 SECOND DO INSERT INTO table_1 VALUES(1);
diff --git a/mysql-test/t/events_stress.test b/mysql-test/t/events_stress.test
index a0101861282..fd1ae34ac3c 100644
--- a/mysql-test/t/events_stress.test
+++ b/mysql-test/t/events_stress.test
@@ -61,11 +61,11 @@ while ($1)
 }
 --enable_query_log
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test2';
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 --sleep 2.5
 DROP DATABASE events_conn1_test2;
 
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test2';
 CREATE DATABASE events_conn1_test3;
 USE events_conn1_test3;
@@ -77,7 +77,7 @@ while ($1)
   dec $1;
 }
 --enable_query_log
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 SELECT COUNT(*) FROM INFORMATION_SCHEMA.EVENTS WHERE EVENT_SCHEMA='events_conn1_test3';
 CREATE DATABASE events_conn1_test4;
 USE events_conn1_test4;
@@ -112,9 +112,9 @@ connection default;
 --send
 DROP DATABASE events_conn1_test2;
 DROP DATABASE events_conn1_test3;
-SET GLOBAL event_scheduler=2;
+SET GLOBAL event_scheduler=off;
 DROP DATABASE events_conn1_test4;
-SET GLOBAL event_scheduler=1;
+SET GLOBAL event_scheduler=on;
 connection conn2;
 reap;
 disconnect conn2;
diff --git a/sql/events.cc b/sql/events.cc
index f4b9b05179d..931ba17341f 100644
--- a/sql/events.cc
+++ b/sql/events.cc
@@ -59,17 +59,39 @@
   eligible for execution.
 */
 
-const char *event_scheduler_state_names[]=
-    { "OFF", "0", "ON", "1", "SUSPEND", "2", NullS };
+/*
+  Keep the order of the first to as in var_typelib
+  sys_var_event_scheduler::value_ptr() references this array. Keep in
+  mind!
+*/
+static const char *opt_event_scheduler_state_names[]=
+    { "OFF", "ON", "0", "1", "DISABLED", NullS };
 
 TYPELIB Events::opt_typelib=
 {
-  array_elements(event_scheduler_state_names)-1,
+  array_elements(opt_event_scheduler_state_names)-1,
   "",
-  event_scheduler_state_names,
+  opt_event_scheduler_state_names,
   NULL
 };
 
+
+/*
+  The order should not be changed. We consider OFF to be equivalent of INT 0
+  And ON of 1. If OFF & ON are interchanged the logic in
+  sys_var_event_scheduler::update() will be broken!
+*/
+static const char *var_event_scheduler_state_names[]= { "OFF", "ON", NullS };
+
+TYPELIB Events::var_typelib=
+{
+  array_elements(var_event_scheduler_state_names)-1,
+  "",
+  var_event_scheduler_state_names,
+  NULL
+};
+
+
 static
 Event_queue events_event_queue;
 
@@ -81,7 +103,8 @@ Event_db_repository events_event_db_repository;
 
 Events Events::singleton;
 
-ulong Events::opt_event_scheduler= 2;
+enum Events::enum_opt_event_scheduler Events::opt_event_scheduler=
+     Events::EVENTS_OFF;
 
 
 /*
@@ -607,6 +630,9 @@ Events::init()
   bool res= FALSE;
   DBUG_ENTER("Events::init");
 
+  if (opt_event_scheduler == Events::EVENTS_DISABLED)
+    DBUG_RETURN(FALSE);
+
   /* We need a temporary THD during boot */
   if (!(thd= new THD()))
   {
@@ -637,12 +663,10 @@ Events::init()
   }
   scheduler->init_scheduler(event_queue);
 
-  if (opt_event_scheduler)
-  {
-    DBUG_ASSERT(opt_event_scheduler == 1 || opt_event_scheduler == 2);
-    if (opt_event_scheduler == 1)
-      res= scheduler->start();
-  }
+  DBUG_ASSERT(opt_event_scheduler == Events::EVENTS_ON ||
+              opt_event_scheduler == Events::EVENTS_OFF);
+  if (opt_event_scheduler == Events::EVENTS_ON)
+    res= scheduler->start();
 
 end:
   delete thd;
@@ -667,10 +691,11 @@ void
 Events::deinit()
 {
   DBUG_ENTER("Events::deinit");
-
-  if (likely(!check_system_tables_error))
+  if (likely(!check_system_tables_error) &&
+      scheduler->get_state() > Event_scheduler::UNINITIALIZED)
   {
     scheduler->stop();
+    DBUG_ASSERT(scheduler->get_state() == Event_scheduler::INITIALIZED);  
     scheduler->deinit_scheduler();
 
     event_queue->deinit_queue();
diff --git a/sql/events.h b/sql/events.h
index 737044ad298..9a820b8521e 100644
--- a/sql/events.h
+++ b/sql/events.h
@@ -48,9 +48,18 @@ public:
     or other scheme will be found.
   */
   friend class Event_queue_element;
-
-  static ulong opt_event_scheduler;
+  
+  /* The order should match the order in opt_typelib */
+  enum enum_opt_event_scheduler
+  {
+    EVENTS_OFF= 0,
+    EVENTS_ON= 1,
+    EVENTS_DISABLED= 5,
+  };
+
+  static enum_opt_event_scheduler opt_event_scheduler;
   static TYPELIB opt_typelib;
+  static TYPELIB var_typelib;
 
   bool
   init();
diff --git a/sql/mysqld.cc b/sql/mysqld.cc
index 58697202461..b8626623b59 100644
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -5072,9 +5072,9 @@ Disable with --skip-bdb (will save memory).",
    (gptr*) &global_system_variables.engine_condition_pushdown,
    (gptr*) &global_system_variables.engine_condition_pushdown,
    0, GET_BOOL, NO_ARG, 0, 0, 0, 0, 0, 0},
+  /* See how it's handled in get_one_option() */
   {"event-scheduler", OPT_EVENT_SCHEDULER, "Enable/disable the event scheduler.",
-   (gptr*) &Events::opt_event_scheduler, (gptr*) &Events::opt_event_scheduler, 0, GET_ULONG,
-    REQUIRED_ARG, 2/*default*/, 0/*min-value*/, 2/*max-value*/, 0, 0, 0},
+   NULL,  NULL, 0, GET_STR, OPT_ARG, 0, 0, 0, 0, 0, 0},
   {"exit-info", 'T', "Used for debugging;  Use at your own risk!", 0, 0, 0,
    GET_LONG, OPT_ARG, 0, 0, 0, 0, 0, 0},
   {"external-locking", OPT_USE_LOCKING, "Use system (external) locking (disabled by default).  With this option enabled you can run myisamchk to test (not repair) tables while the MySQL server is running. Disable with --skip-external-locking.",
@@ -7423,20 +7423,33 @@ get_one_option(int optid, const struct my_option *opt __attribute__((unused)),
 #endif
   case OPT_EVENT_SCHEDULER:
     if (!argument)
-      Events::opt_event_scheduler= 2;
+      Events::opt_event_scheduler= Events::EVENTS_DISABLED;
     else
     {
       int type;
-      if ((type=find_type(argument, &Events::opt_typelib, 1)) <= 0)
-      {
-	fprintf(stderr,"Unknown option to event-scheduler: %s\n",argument);
-	exit(1);
-      }
       /* 
-        type=  1     2      3   4     5    6
-             (OFF |  0) - (ON | 1) - (2 | SUSPEND)
+        type=     5          1   2      3   4
+             (DISABLE ) - (OFF | ON) - (0 | 1)
       */
-      Events::opt_event_scheduler= (type-1) / 2;
+      switch ((type=find_type(argument, &Events::opt_typelib, 1))) {
+      case 0:
+	fprintf(stderr, "Unknown option to event-scheduler: %s\n",argument);
+	exit(1);
+      case 5: /* OPT_DISABLED */
+        Events::opt_event_scheduler= Events::EVENTS_DISABLED;
+        break;
+      case 2: /* OPT_ON  */
+      case 4: /* 1   */
+        Events::opt_event_scheduler= Events::EVENTS_ON;
+        break;
+      case 1: /* OPT_OFF */
+      case 3: /*  0  */
+        Events::opt_event_scheduler= Events::EVENTS_OFF;
+        break;
+      default:
+        DBUG_ASSERT(0);
+        unireg_abort(1);
+      }
     }
     break;
   case (int) OPT_SKIP_NEW:
diff --git a/sql/set_var.cc b/sql/set_var.cc
index f10df7fa6f8..d2764e13ae3 100644
--- a/sql/set_var.cc
+++ b/sql/set_var.cc
@@ -3914,6 +3914,7 @@ bool sys_var_thd_dbug::update(THD *thd, set_var *var)
   return 0;
 }
 
+
 byte *sys_var_thd_dbug::value_ptr(THD *thd, enum_var_type type, LEX_STRING *b)
 {
   char buf[256];
@@ -3925,6 +3926,12 @@ byte *sys_var_thd_dbug::value_ptr(THD *thd, enum_var_type type, LEX_STRING *b)
 }
 
 
+bool sys_var_event_scheduler::check(THD *thd, set_var *var)
+{
+  return check_enum(thd, var, &Events::var_typelib);
+}
+
+
 /*
    The update method of the global variable event_scheduler.
    If event_scheduler is switched from 0 to 1 then the scheduler main
@@ -3946,29 +3953,27 @@ sys_var_event_scheduler::update(THD *thd, set_var *var)
   int res;
   /* here start the thread if not running. */
   DBUG_ENTER("sys_var_event_scheduler::update");
-  if (Events::opt_event_scheduler == 0)
+  if (Events::opt_event_scheduler == Events::EVENTS_DISABLED)
   {
-    my_error(ER_OPTION_PREVENTS_STATEMENT, MYF(0), "--event-scheduler=0");
+    my_error(ER_OPTION_PREVENTS_STATEMENT, MYF(0), "--event-scheduler=DISABLED");
     DBUG_RETURN(TRUE);
   }
 
   DBUG_PRINT("new_value", ("%lu", (bool)var->save_result.ulong_value));
 
-  if (var->save_result.ulonglong_value < 1 ||
-      var->save_result.ulonglong_value > 2)
-  {
-    char buf[64];
-    my_error(ER_WRONG_VALUE_FOR_VAR, MYF(0), "event_scheduler",
-             llstr(var->save_result.ulonglong_value, buf));
-    DBUG_RETURN(TRUE);
-  }
-  if (var->save_result.ulonglong_value == 1)
+  Item_result var_type= var->value->result_type();
+
+  if (var->save_result.ulong_value == Events::EVENTS_ON)
     res= Events::get_instance()->start_execution_of_events();
-  else
+  else if (var->save_result.ulong_value == Events::EVENTS_OFF)
     res= Events::get_instance()->stop_execution_of_events();
-
+  else
+  {
+    DBUG_ASSERT(0);
+  }
   if (res)
     my_error(ER_EVENT_SET_VAR_ERROR, MYF(0));
+
   DBUG_RETURN((bool) res);
 }
 
@@ -3976,14 +3981,15 @@ sys_var_event_scheduler::update(THD *thd, set_var *var)
 byte *sys_var_event_scheduler::value_ptr(THD *thd, enum_var_type type,
                                          LEX_STRING *base)
 {
-  if (Events::opt_event_scheduler == 0)
-    thd->sys_var_tmp.long_value= 0;
+  int state;
+  if (Events::opt_event_scheduler == Events::EVENTS_DISABLED)
+    state= Events::EVENTS_DISABLED;              // This should be DISABLED
   else if (Events::get_instance()->is_execution_of_events_started())
-    thd->sys_var_tmp.long_value= 1;
+    state= Events::EVENTS_ON;                    // This should be ON
   else
-    thd->sys_var_tmp.long_value= 2;
+    state= Events::EVENTS_OFF;                   // This should be OFF
 
-  return (byte*) &thd->sys_var_tmp;
+  return (byte*) Events::opt_typelib.type_names[state];
 }
 
 
diff --git a/sql/set_var.h b/sql/set_var.h
index a63bcc4a55d..01669b378e1 100644
--- a/sql/set_var.h
+++ b/sql/set_var.h
@@ -932,6 +932,12 @@ public:
     sys_var_long_ptr(name_arg, NULL, NULL) {};
   bool update(THD *thd, set_var *var);
   byte *value_ptr(THD *thd, enum_var_type type, LEX_STRING *base);
+  SHOW_TYPE type() { return SHOW_CHAR; }
+  bool check(THD *thd, set_var *var);
+  bool check_update_type(Item_result type)
+  {
+    return type != STRING_RESULT && type != INT_RESULT;
+  }
 };
 
 #ifdef HAVE_ROW_BASED_REPLICATION