Engine directory for ticket #1

Engine/source/platform/async/asyncUpdate.h

@@ -0,0 +1,162 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#ifndef _ASYNCUPDATE_H_
+#define _ASYNCUPDATE_H_
+
+#ifndef _PLATFORM_THREADS_THREAD_H_
+#  include "platform/threads/thread.h"
+#endif
+#ifndef _THREADSAFEREFCOUNT_H_
+#  include "platform/threads/threadSafeRefCount.h"
+#endif
+#ifndef _THREADSAFEDEQUE_H_
+#  include "platform/threads/threadSafeDeque.h"
+#endif
+
+
+class IPolled;
+
+//--------------------------------------------------------------------------
+//    Async update list.
+//--------------------------------------------------------------------------
+
+/// This structure keeps track of the objects that need
+/// updating.
+class AsyncUpdateList : public ThreadSafeRefCount< AsyncUpdateList >
+{
+   protected:
+
+      typedef ThreadSafeDeque< IPolled* > UpdateList;
+
+      /// List of structures currently in the update loop.
+      UpdateList mUpdateList;
+
+   public:
+
+      virtual ~AsyncUpdateList() {}
+
+      /// Update the structures currently on the processing list.
+      ///
+      /// @param timeOut Soft limit in milliseconds on the time
+      ///   spent on flushing the list.  Default of -1 means no
+      ///   limit and function will only return, if update list
+      ///   has been fully flushed.
+      virtual void process( S32 timeOut = -1 );
+
+      /// Add the structure to the update list.  It will stay
+      /// on this list, until its update() method returns false.
+      ///
+      /// @note This can be called on different threads.
+      virtual void add( IPolled* ptr )
+      {
+         mUpdateList.pushBack( ptr );
+      }
+};
+
+//--------------------------------------------------------------------------
+//    Async update thread.
+//--------------------------------------------------------------------------
+
+/// Abstract baseclass for async update threads.
+class AsyncUpdateThread : public Thread, public ThreadSafeRefCount< AsyncUpdateThread >
+{
+   public:
+
+      typedef Thread Parent;
+
+   protected:
+
+      /// Name of this thread.
+      String mName;
+
+      /// Platform-dependent event data.
+      void* mUpdateEvent;
+
+      /// The update list processed on this thread.
+      ThreadSafeRef< AsyncUpdateList > mUpdateList;
+
+      /// Wait for an update event being triggered and
+      /// immediately reset the event.
+      ///
+      /// @note Note that this must be an atomic operation to avoid
+      ///   a race condition.  Immediately resetting the event shields
+      ///   us from event releases happening during us updating getting
+      ///   ignored.
+      virtual void _waitForEventAndReset();
+
+   public:
+
+      /// Create the update thread.
+      /// The thread won't immediately start (we have virtual functions
+      /// so construction needs to finish first) and will not auto-delete
+      /// itself.
+      AsyncUpdateThread( String name, AsyncUpdateList* updateList );
+
+      virtual ~AsyncUpdateThread();
+
+      virtual void run( void* );
+
+      /// Trigger the update event to notify the thread about
+      /// pending updates.
+      virtual void triggerUpdate();
+
+      ///
+      const String& getName() const { return mName; }
+
+      ///
+      void* getUpdateEvent() const { return mUpdateEvent; }
+};
+
+/// Extension to update thread that also does automatic
+/// periodic updates.
+class AsyncPeriodicUpdateThread : public AsyncUpdateThread
+{
+      typedef AsyncUpdateThread Parent;
+
+   protected:
+
+      /// Platform-dependent timer event.
+      void* mUpdateTimer;
+      
+      /// Time between periodic updates in milliseconds.
+      U32 mIntervalMS;
+
+      virtual void _waitForEventAndReset();
+
+   public:
+
+      enum
+      {
+         /// Default interval between periodic updates in milliseconds.
+         DEFAULT_UPDATE_INTERVAL = 4000
+      };
+
+      ///
+      AsyncPeriodicUpdateThread(  String name,
+                                  AsyncUpdateList* updateList,
+                                  U32 intervalMS = DEFAULT_UPDATE_INTERVAL );
+
+      virtual ~AsyncPeriodicUpdateThread();
+};
+
+#endif // _TORQUE_CORE_ASYNC_ASYNCUPDATE_H_