WL #3337 (Events new architecture)

Final stroke, events should be loaded from disk on server startup.
Also check the validity of their bodies if possible during loading.


sql/event_data_objects.cc:
  Remove Event_job_data::free_sp(), move the code to the destructor
  Change the way we change the security context
  Steal some code from sql_parse.cc
sql/event_data_objects.h:
  Remove free_sp()
  Make compile() public, to be used when booting for verifying the integrity of mysql.event
sql/event_queue.cc:
  Make the queue load events from disk on server boot.
  Compile and thus check for integrity the events.
sql/event_queue.h:
  shift methods around. add queue_loaded boolean.
sql/event_scheduler.cc:
  Rename init_event_thread() to pre_init_event_thread()
  and make it more generic.
  Add post_init_event_thread()
  Export these two as well as deinit_event_thread().
  Now it is quite easy to write code to spawn a new event thread
  whenever needed.
sql/event_scheduler.h:
  export pre_init_event_thread(), post_init_event_thread() and deinit_event_thread()
  to simplify writing of thread functions.
sql/events.cc:
  Events::init() returns only one error code, then make it bool
sql/events.h:
  Events::init() returns only one error code, then make it bool
sql/mysqld.cc:
  Check the return code of Events::init()
sql/sp_head.cc:
  Add trace info
sql/sql_class.cc:
  Reorganize thd::change_security_context() to load main_security_ctx
sql/sql_class.h:
  Reorganize thd::change_security_context() to load main_security_ctx
sql/sql_lex.cc:
  Initialize lex->spname
sql/sql_yacc.yy:
  Add a comment

1 files changed, 17 insertions, 14 deletions

diff --git a/sql/event_queue.h b/sql/event_queue.h
index b7962d14a89..3270938e881 100644
--- a/sql/event_queue.h
+++ b/sql/event_queue.h
@@ -68,12 +68,13 @@ public:
   bool
   dump_internal_status(THD *thd);
 
+  int
+  load_events_from_db(THD *thd);
+
 protected:
   Event_queue_element *
   find_n_remove_event(LEX_STRING db, LEX_STRING name);
 
-  int
-  load_events_from_db(THD *thd);
 
   void
   drop_matching_events(THD *thd, LEX_STRING pattern,
@@ -82,11 +83,24 @@ protected:
   void
   empty_queue();
 
+  void
+  notify_observers();
+
+  void
+  dbug_dump_queue(time_t now);
+
   /* LOCK_event_queue is the mutex which protects the access to the queue. */
   pthread_mutex_t LOCK_event_queue;
 
   Event_db_repository *db_repository;
 
+  Event_scheduler *scheduler;
+
+  /* The sorted queue with the Event_job_data objects */
+  QUEUE queue;
+
+  bool queue_loaded;
+
   uint mutex_last_locked_at_line;
   uint mutex_last_unlocked_at_line;
   uint mutex_last_attempted_lock_at_line;
@@ -95,24 +109,13 @@ protected:
   const char* mutex_last_attempted_lock_in_func;
   bool mutex_queue_data_locked;
   bool mutex_queue_data_attempting_lock;
-
+  
   /* helper functions for working with mutexes & conditionals */
   void
   lock_data(const char *func, uint line);
 
   void
   unlock_data(const char *func, uint line);
-
-  void
-  notify_observers();
-
-  void
-  dbug_dump_queue(time_t now);
-
-  Event_scheduler *scheduler;
-
-  /* The sorted queue with the Event_job_data objects */
-  QUEUE queue;
 };
 
 #endif /* _EVENT_QUEUE_H_ */