DBLayer:

- Use ACE_Future and ACE_Future_Set for async SQL queries with callback
* Callbacks will now be executed from the thread and object that scheduled the request, instead of the world runnable thread (and thus are no longer dependent on the 50ms forced sleep time).
* This design gets rid of a potential DOS loophole in the resultqueue system - unique requests will be cancelled when re-requested.
- Drop now redundant SQLQueryTask, SQLResultQueue, SQLResultQueueTask operations.
- Drop now redundant CharacterHandler class
- Change static callback functions in WorldSession to normal functions.

Thanks to Derex and Zor for advice along the way.

--HG--
branch : trunk

src/server/game/World/World.cpp

@@ -54,7 +54,6 @@
 #include "VMapFactory.h"
 #include "GameEventMgr.h"
 #include "PoolMgr.h"
-#include "AsyncDatabaseImpl.h"
 #include "GridNotifiersImpl.h"
 #include "CellImpl.h"
 #include "InstanceSaveMgr.h"
@@ -103,7 +102,6 @@ World::World()
     m_maxQueuedSessionCount = 0;
     m_PlayerCount = 0;
     m_MaxPlayerCount = 0;
-    m_resultQueue = NULL;
     m_NextDailyQuestReset = 0;
     m_NextWeeklyQuestReset = 0;
     m_scheduledScripts = 0;
@@ -134,8 +132,6 @@ World::~World()
 
     VMAP::VMapFactory::clear();
 
-    delete m_resultQueue;
-
     //TODO free addSessQueue
 }
 
@@ -1979,8 +1975,8 @@ void World::Update(uint32 diff)
     RecordTimeDiff("UpdateLFGMgr");
 
     // execute callbacks from sql queries that were queued recently
-    UpdateResultQueue();
-    RecordTimeDiff("UpdateResultQueue");
+    ProcessQueryCallbacks();
+    RecordTimeDiff("ProcessQueryCallbacks");
 
     ///- Erase corpses once every 20 minutes
     if (m_timers[WUPDATE_CORPSES].Passed())
@@ -2500,21 +2496,12 @@ void World::SendRNDBroadcast()
     }
 }
 
-void World::InitResultQueue()
-{
-    m_resultQueue = new SQLResultQueue;
-    CharacterDatabase.SetResultQueue(m_resultQueue);
-}
-
-void World::UpdateResultQueue()
-{
-    m_resultQueue->Update();
-}
-
 void World::UpdateRealmCharCount(uint32 accountId)
 {
-    CharacterDatabase.AsyncPQuery(this, &World::_UpdateRealmCharCount, accountId,
-        "SELECT COUNT(guid) FROM characters WHERE account = '%u'", accountId);
+    m_realmCharCallback.SetParam(accountId);
+    m_realmCharCallback.SetFutureResult(
+        LoginDatabase.AsyncPQuery("SELECT COUNT(guid) FROM characters WHERE account = '%u'", accountId)
+        );
 }
 
 void World::_UpdateRealmCharCount(QueryResult_AutoPtr resultCharCount, uint32 accountId)
@@ -2742,3 +2729,17 @@ uint64 World::getWorldState(uint32 index) const
     WorldStatesMap::const_iterator it = m_worldstates.find(index);
     return it != m_worldstates.end() ? it->second : 0;
 }
+
+void World::ProcessQueryCallbacks()
+{
+    QueryResult_AutoPtr result;
+
+    //-UpdateRealmCharCount
+    if (m_realmCharCallback.IsReady())
+    {
+        uint32 param = m_realmCharCallback.GetParam();
+        m_realmCharCallback.GetResult(result);
+        _UpdateRealmCharCount(result, param);
+        m_realmCharCallback.FreeResult();
+    }
+}

src/server/game/World/World.h

@@ -31,6 +31,7 @@
 #include "SharedDefines.h"
 #include "ace/Atomic_Op.h"
 #include "QueryResult.h"
+#include "Callback.h"
 
 #include <map>
 #include <set>
@@ -42,7 +43,6 @@ class WorldSession;
 class Player;
 struct ScriptAction;
 struct ScriptInfo;
-class SQLResultQueue;
 class QueryResult;
 class WorldSocket;
 class SystemMgr;
@@ -670,9 +670,6 @@ class World
         void ProcessCliCommands();
         void QueueCliCommand(CliCommandHolder* commandHolder) { cliCmdQueue.add(commandHolder); }
 
-        void UpdateResultQueue();
-        void InitResultQueue();
-
         void ForceGameEventUpdate();
 
         void UpdateRealmCharCount(uint32 accid);
@@ -768,7 +765,6 @@ class World
 
         // CLI command holder to be thread safe
         ACE_Based::LockedQueue<CliCommandHolder*,ACE_Thread_Mutex> cliCmdQueue;
-        SQLResultQueue *m_resultQueue;
 
         // next daily quests and random bg reset time
         time_t m_NextDailyQuestReset;
@@ -787,6 +783,10 @@ class World
         std::string m_CreatureEventAIVersion;
 
         std::list<std::string> m_Autobroadcasts;
+
+    private:
+        void ProcessQueryCallbacks();
+        QueryCallback<uint32> m_realmCharCallback;
 };
 
 extern uint32 realmID;