WL#1034

updated sources


sql/event.cc:
  update
  put some error calls to the places they occur
sql/event.h:
  - change the default (does not work in STRICT mode)
sql/event_executor.cc:
  move mutex initialization to evex_init_mutexes so init_events() can be reused when the
  main thread does not work and set global event_scheduler=1; (this will start the thread)
  The main thread is now visible with show processlist and can be killed.
sql/event_priv.h:
  don't use anymore SP for opening table
sql/event_timed.cc:
  don't use anymore SP routines for opening mysql.event
sql/mysqld.cc:
  shutdown_events() should be maximal at the end of the server because
  it destroys mutexes of EVEX. The call should not be in the main thread.
sql/set_var.cc:
  make sys_var_event_executor subclass sys_var_bool_ptr
  to overload ::update() method - needed to start a
  killed (non-running) evex main thread
sql/set_var.h:
  declare class sys_var_event_executor
sql/share/errmsg.txt:
  2 new messages

sql/event.h

@@ -214,8 +214,8 @@ CREATE TABLE `event` (
   `execute_at` datetime default NULL,
   `transient_expression` int(11) default NULL,
   `interval_type` enum('YEAR','QUARTER','MONTH','DAY','HOUR','MINUTE','WEEK','SECOND','MICROSECOND','YEAR_MONTH','DAY_HOUR','DAY_MINUTE','DAY_SECOND','HOUR_MINUTE','HOUR_SECOND','MINUTE_SECOND','DAY_MICROSECOND','HOUR_MICROSECOND','MINUTE_MICROSECOND','SECOND_MICROSECOND') default NULL,
-  `created` timestamp NOT NULL default '0000-00-00 00:00:00',
-  `modified` timestamp NOT NULL default '0000-00-00 00:00:00',
+  `created` timestamp NOT NULL,
+  `modified` timestamp NOT NULL,
   `last_executed` datetime default NULL,
   `starts` datetime default NULL,
   `ends` datetime default NULL,

sql/event_executor.cc

@@ -36,6 +36,7 @@ my_bool event_executor_running_global_var= false;
 
 extern ulong thread_created;
 
+static my_bool evex_mutexes_initted= false;
 
 static int
 evex_load_events_from_db(THD *thd);
@@ -50,6 +51,19 @@ evex_load_events_from_db(THD *thd);
 pthread_handler_t event_executor_worker(void *arg);
 pthread_handler_t event_executor_main(void *arg);
 
+static
+void evex_init_mutexes()
+{
+  if (evex_mutexes_initted)
+  {
+    evex_mutexes_initted= true;
+    return;
+  }
+  pthread_mutex_init(&LOCK_event_arrays, MY_MUTEX_INIT_FAST);
+  pthread_mutex_init(&LOCK_workers_count, MY_MUTEX_INIT_FAST);
+  pthread_mutex_init(&LOCK_evex_running, MY_MUTEX_INIT_FAST);
+}
+
 int
 init_events()
 {
@@ -59,15 +73,15 @@ init_events()
 
   DBUG_PRINT("info",("Starting events main thread"));
 
-  pthread_mutex_init(&LOCK_event_arrays, MY_MUTEX_INIT_FAST);
-  pthread_mutex_init(&LOCK_workers_count, MY_MUTEX_INIT_FAST);
-  pthread_mutex_init(&LOCK_evex_running, MY_MUTEX_INIT_FAST);
+  evex_init_mutexes();
   
   VOID(pthread_mutex_lock(&LOCK_evex_running));
   evex_is_running= false;  
   event_executor_running_global_var= false;
   VOID(pthread_mutex_unlock(&LOCK_evex_running));
 
+  DBUG_RETURN(0);
+/*
 #ifndef DBUG_FAULTY_THR
   //TODO Andrey: Change the error code returned!
   if (pthread_create(&th, NULL, event_executor_main, (void*)NULL))
@@ -77,6 +91,7 @@ init_events()
 #endif
 
   DBUG_RETURN(0);
+*/
 }
 
 
@@ -94,6 +109,7 @@ shutdown_events()
   DBUG_VOID_RETURN;
 }
 
+#ifdef ANDREY_0
 
 static int
 init_event_thread(THD* thd)
@@ -165,7 +181,7 @@ pthread_handler_t event_executor_main(void *arg)
     goto err;
 
   // make this thread invisible it has no vio -> show processlist won't see
-  thd->system_thread= 0;
+  thd->system_thread= 1;
 
   VOID(pthread_mutex_lock(&LOCK_thread_count));
   threads.append(thd);
@@ -350,7 +366,7 @@ err_no_thd:
   free_root(&evex_mem_root, MYF(0));
   sql_print_information("Event executor stopped");
 
-  shutdown_events();
+//  shutdown_events();
 
   my_thread_end();
   pthread_exit(0);
@@ -391,7 +407,7 @@ pthread_handler_t event_executor_worker(void *event_void)
   thd->init_for_queries();
 
   // make this thread visible it has no vio -> show processlist needs this flag
-  thd->system_thread= 0;
+  thd->system_thread= 1;
 
   VOID(pthread_mutex_lock(&LOCK_thread_count));
   threads.append(thd);
@@ -531,3 +547,20 @@ end:
                     ("Events loaded from DB. Status code %d", ret));
   DBUG_RETURN(ret);
 }
+
+#endif
+
+bool sys_var_event_executor::update(THD *thd, set_var *var)
+{
+#ifdef ANDREY_0
+  // here start the thread if not running.
+  VOID(pthread_mutex_lock(&LOCK_evex_running));
+  if ((my_bool) var->save_result.ulong_value && !evex_is_running) {
+    VOID(pthread_mutex_unlock(&LOCK_evex_running));
+    init_events();
+  } else 
+    VOID(pthread_mutex_unlock(&LOCK_evex_running));
+#endif  
+  return sys_var_bool_ptr::update(thd, var);
+}
+

sql/event_priv.h

@@ -17,9 +17,6 @@
 #ifndef _EVENT_PRIV_H_
 #define _EVENT_PRIV_H_
 
-#define EVEX_OPEN_TABLE_FOR_UPDATE() \
-       open_proc_type_table_for_update(thd, "event", &mysql_event_table_exists)
-
 
 enum
 {
@@ -54,4 +51,6 @@ extern pthread_mutex_t LOCK_event_arrays,
 int
 my_time_compare(TIME *a, TIME *b);
 
+
+TABLE *evex_open_event_table(THD *thd, enum thr_lock_type lock_type);             
 #endif /* _EVENT_PRIV_H_ */

sql/event_timed.cc

@@ -719,7 +719,7 @@ event_timed::update_fields(THD *thd)
   if (!(m_status_changed || m_last_executed_changed))
     goto done;
   
-  if (!(table= EVEX_OPEN_TABLE_FOR_UPDATE()))
+  if (!(table= evex_open_event_table(thd, TL_WRITE)))
     DBUG_RETURN(SP_OPEN_TABLE_FAILED);
 
   if ((ret= sp_db_find_routine_aux(thd, 0/*notype*/, m_db, m_name, table)))

sql/mysqld.cc

@@ -3568,6 +3568,7 @@ we force server id to 2, but this MySQL server will not act as a slave.");
   clean_up(1);
   wait_for_signal_thread_to_end();
   clean_up_mutexes();
+  shutdown_events();
   my_end(opt_endinfo ? MY_CHECK_ERROR | MY_GIVE_INFO : 0);
  
   exit(0);

sql/set_var.cc

@@ -207,7 +207,7 @@ sys_var_long_ptr	sys_delayed_insert_timeout("delayed_insert_timeout",
 						   &delayed_insert_timeout);
 sys_var_long_ptr	sys_delayed_queue_size("delayed_queue_size",
 					       &delayed_queue_size);
-sys_var_bool_ptr        sys_event_executor("event_scheduler",
+sys_var_event_executor        sys_event_executor("event_scheduler",
                                                &event_executor_running_global_var);
 sys_var_long_ptr	sys_expire_logs_days("expire_logs_days",
 					     &expire_logs_days);
@@ -3364,6 +3364,7 @@ bool sys_var_trust_routine_creators::update(THD *thd, set_var *var)
   return sys_var_bool_ptr::update(thd, var);
 }
 
+
 /****************************************************************************
   Used templates
 ****************************************************************************/

sql/set_var.h

@@ -782,6 +782,17 @@ public:
   bool update(THD *thd, set_var *var);
 };
 
+
+class sys_var_event_executor :public sys_var_bool_ptr
+{
+  /* We need a derived class only to have a warn_deprecated() */
+public:
+  sys_var_event_executor(const char *name_arg, my_bool *value_arg) :
+    sys_var_bool_ptr(name_arg, value_arg) {};
+  bool update(THD *thd, set_var *var);
+};
+
+
 /****************************************************************************
   Classes for parsing of the SET command
 ****************************************************************************/

sql/share/errmsg.txt

@@ -5737,3 +5737,7 @@ ER_EVENT_ENDS_BEFORE_STARTS
         eng "ENDS must be after STARTS"
 ER_EVENT_EXEC_TIME_IN_THE_PAST
         eng "Activation (AT) time is in the past"
+ER_EVENT_OPEN_TABLE_FAILED
+        eng "Failed to open mysql.event"
+ER_EVENT_NEITHER_M_EXPR_NOR_M_AT
+        eng "No datetime expression provided"