camerauis/cameraapp/generic/src/cameracontroller/cambuffershare.cpp
changeset 0 1ddebce53859
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/camerauis/cameraapp/generic/src/cameracontroller/cambuffershare.cpp	Thu Jan 07 16:18:56 2010 +0200
@@ -0,0 +1,124 @@
+/*
+* Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies). 
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:  Implementation of CCamBufferShare class.
+*                Wrapper around to store and handle sharing of buffer
+*                implementing MCameraBuffer interface. Counts references
+*                and frees the stored buffer, when no client uses it.
+*                
+*
+*/
+
+
+
+// ===========================================================================
+// Includes
+#include <ecam.h> // MCameraBuffer
+#include "camlogging.h"
+#include "cambuffershare.h"
+
+// ===========================================================================
+// Static data initialisation
+#ifdef _DEBUG
+  TInt CCamBufferShare::isTotalBufferCount = 0;
+#endif // _DEBUG
+
+
+// ===========================================================================
+// Class methods
+
+// ---------------------------------------------------------------------------
+// Constructor
+// ---------------------------------------------------------------------------
+//
+CCamBufferShare::CCamBufferShare( MCameraBuffer* aSharedBuffer )
+  : iSharedBuffer( aSharedBuffer ),
+    iReferenceCount( 0 )
+  {
+#ifdef _DEBUG
+  ++isTotalBufferCount;
+#endif // _DEBUG
+  }
+
+// ---------------------------------------------------------------------------
+// Destructor
+//   Private, Release is to be used by clients.
+// ---------------------------------------------------------------------------
+//
+CCamBufferShare::~CCamBufferShare()
+  {
+  PRINT( _L("Camera => ~CCamBufferShare") );  
+  if( iSharedBuffer )
+    {
+    iSharedBuffer->Release();
+    iSharedBuffer = NULL;
+    }
+#ifdef _DEBUG
+  --isTotalBufferCount;
+#endif
+  PRINT( _L("Camera <= ~CCamBufferShare") );  
+  }
+
+// ---------------------------------------------------------------------------
+// Return the shared buffer.
+// Ownership never transferred to caller.
+// ---------------------------------------------------------------------------
+//
+MCameraBuffer* 
+CCamBufferShare::SharedBuffer()
+  {
+  return iSharedBuffer;
+  }
+  
+// ---------------------------------------------------------------------------
+// Signal, that new client uses this buffer.
+// ---------------------------------------------------------------------------
+//
+void 
+CCamBufferShare::Reserve()
+  {
+  ++iReferenceCount;
+  }
+
+// ---------------------------------------------------------------------------
+// Signal that one client has stopped using this buffer.
+// ---------------------------------------------------------------------------
+//
+void 
+CCamBufferShare::Release()
+  {
+  --iReferenceCount;
+
+  if( iReferenceCount <= 0 )
+    {
+    delete this;
+    }
+  }
+
+#ifdef _DEBUG
+// ---------------------------------------------------------------------------
+// TotalBufferShareCount <<static>>
+//
+// Debug method to follow the total amount of shared buffers in use.
+// ---------------------------------------------------------------------------
+//
+TInt 
+CCamBufferShare::TotalBufferShareCount()
+  {
+  return isTotalBufferCount;
+  }
+#endif // _DEBUG
+
+
+// end of file
+