camerauis/cameraapp/generic/src/cameracontroller/cambuffershare.cpp
changeset 19 d9aefe59d544
parent 3 8b2d6d0384b0
child 21 fa6d9f75d6a6
child 28 3075d9b614e6
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3:8b2d6d0384b0 19:d9aefe59d544
     1 /*
       
     2 * Copyright (c) 2007 Nokia Corporation and/or its subsidiary(-ies). 
       
     3 * All rights reserved.
       
     4 * This component and the accompanying materials are made available
       
     5 * under the terms of "Eclipse Public License v1.0"
       
     6 * which accompanies this distribution, and is available
       
     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".
       
     8 *
       
     9 * Initial Contributors:
       
    10 * Nokia Corporation - initial contribution.
       
    11 *
       
    12 * Contributors:
       
    13 *
       
    14 * Description:  Implementation of CCamBufferShare class.
       
    15 *                Wrapper around to store and handle sharing of buffer
       
    16 *                implementing MCameraBuffer interface. Counts references
       
    17 *                and frees the stored buffer, when no client uses it.
       
    18 *                
       
    19 *
       
    20 */
       
    21 
       
    22 
       
    23 
       
    24 // ===========================================================================
       
    25 // Includes
       
    26 #include <ecam.h> // MCameraBuffer
       
    27 #include "camlogging.h"
       
    28 #include "cambuffershare.h"
       
    29 
       
    30 // ===========================================================================
       
    31 // Static data initialisation
       
    32 #ifdef _DEBUG
       
    33   TInt CCamBufferShare::isTotalBufferCount = 0;
       
    34 #endif // _DEBUG
       
    35 
       
    36 
       
    37 // ===========================================================================
       
    38 // Class methods
       
    39 
       
    40 // ---------------------------------------------------------------------------
       
    41 // Constructor
       
    42 // ---------------------------------------------------------------------------
       
    43 //
       
    44 CCamBufferShare::CCamBufferShare( MCameraBuffer* aSharedBuffer )
       
    45   : iSharedBuffer( aSharedBuffer ),
       
    46     iReferenceCount( 0 )
       
    47   {
       
    48 #ifdef _DEBUG
       
    49   ++isTotalBufferCount;
       
    50 #endif // _DEBUG
       
    51   }
       
    52 
       
    53 // ---------------------------------------------------------------------------
       
    54 // Destructor
       
    55 //   Private, Release is to be used by clients.
       
    56 // ---------------------------------------------------------------------------
       
    57 //
       
    58 CCamBufferShare::~CCamBufferShare()
       
    59   {
       
    60   PRINT( _L("Camera => ~CCamBufferShare") );  
       
    61   if( iSharedBuffer )
       
    62     {
       
    63     iSharedBuffer->Release();
       
    64     iSharedBuffer = NULL;
       
    65     }
       
    66 #ifdef _DEBUG
       
    67   --isTotalBufferCount;
       
    68 #endif
       
    69   PRINT( _L("Camera <= ~CCamBufferShare") );  
       
    70   }
       
    71 
       
    72 // ---------------------------------------------------------------------------
       
    73 // Return the shared buffer.
       
    74 // Ownership never transferred to caller.
       
    75 // ---------------------------------------------------------------------------
       
    76 //
       
    77 MCameraBuffer* 
       
    78 CCamBufferShare::SharedBuffer()
       
    79   {
       
    80   return iSharedBuffer;
       
    81   }
       
    82   
       
    83 // ---------------------------------------------------------------------------
       
    84 // Signal, that new client uses this buffer.
       
    85 // ---------------------------------------------------------------------------
       
    86 //
       
    87 void 
       
    88 CCamBufferShare::Reserve()
       
    89   {
       
    90   ++iReferenceCount;
       
    91   }
       
    92 
       
    93 // ---------------------------------------------------------------------------
       
    94 // Signal that one client has stopped using this buffer.
       
    95 // ---------------------------------------------------------------------------
       
    96 //
       
    97 void 
       
    98 CCamBufferShare::Release()
       
    99   {
       
   100   --iReferenceCount;
       
   101 
       
   102   if( iReferenceCount <= 0 )
       
   103     {
       
   104     delete this;
       
   105     }
       
   106   }
       
   107 
       
   108 #ifdef _DEBUG
       
   109 // ---------------------------------------------------------------------------
       
   110 // TotalBufferShareCount <<static>>
       
   111 //
       
   112 // Debug method to follow the total amount of shared buffers in use.
       
   113 // ---------------------------------------------------------------------------
       
   114 //
       
   115 TInt 
       
   116 CCamBufferShare::TotalBufferShareCount()
       
   117   {
       
   118   return isTotalBufferCount;
       
   119   }
       
   120 #endif // _DEBUG
       
   121 
       
   122 
       
   123 // end of file
       
   124