*Do not create new instance when player is logging in. (Try to fix "Instance Relog & Reset Exploit")

--HG--
branch : trunk

src/game/CharacterHandler.cpp

@@ -610,7 +610,9 @@ void WorldSession::HandlePlayerLogin(LoginQueryHolder * holder)
         }
     }
 
-    if (!pCurrChar->GetMap()->Add(pCurrChar))
+    {
+        Map *map = pCurrChar->GetMap();
+        if (!map || !map->Add(pCurrChar))
         {
             AreaTrigger const* at = objmgr.GetGoBackTrigger(pCurrChar->GetMapId());
             if(at)
@@ -618,6 +620,7 @@ void WorldSession::HandlePlayerLogin(LoginQueryHolder * holder)
             else
                 pCurrChar->TeleportTo(pCurrChar->m_homebindMapId, pCurrChar->m_homebindX, pCurrChar->m_homebindY, pCurrChar->m_homebindZ, pCurrChar->GetOrientation());
         }
+    }
 
     ObjectAccessor::Instance().AddObject(pCurrChar);
     //sLog.outDebug("Player %s added to Map.",pCurrChar->GetName());

src/game/MapInstanced.cpp

@@ -179,13 +179,18 @@ Map* MapInstanced::GetInstance(const WorldObject* obj)
                     map = CreateInstance(NewInstanceId, pSave, pSave->GetDifficulty());
                 return map;
             }
-            else
+            else if(!player->GetSession()->PlayerLoading())
             {
                 // if no instanceId via group members or instance saves is found
                 // the instance will be created for the first time
                 NewInstanceId = MapManager::Instance().GenerateInstanceId();
                 return CreateInstance(NewInstanceId, NULL, player->GetDifficulty());
             }
+            else
+            {
+                sLog.outError("MAPINSTANCED: Player %s is trying to create instance (MapId %u) when login.", player->GetName(), player->GetMapId());
+                return NULL;
+            }
         }
     }
 }