1 // Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

     6 // at the URL "http://www.eclipse.org/legal/epl-v10.html".

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 //

    15 

    16 #ifndef __APGCOMMONUTILS_H__

    17 #define __APGCOMMONUTILS_H__

    18 

    19 #include <e32base.h>

    20 #include <s32strm.h>

    21 #include <s32buf.h>

    22 #include<usif/scr/appregentries.h>

    23 

    24 

    25 /**

    26 Implementation of the MStreamBuf interface that throws away all

    27 data written to it but keeps track of how many bytes have been

    28 written to it.  It does not support reading.

    29 */

    30 class TNullBuf : public MStreamBuf

    31     {

    32 public:

    33     inline TNullBuf();

    34     inline TUint BytesWritten();

    35 private:

    36     inline virtual void DoWriteL(const TAny* aPtr,TInt aLength);

    37 private:

    38     TUint iBytesWritten;

    39     };

    40 

    41 /**

    42 A write stream that throws away all its input, but keeps track of how many

    43 bytes have been written to it.  It is used for determining the amount of

    44 memory needed to store externalised objects.

    45 */

    46 class RNullWriteStream : public RWriteStream

    47     {

    48 public:

    49     inline RNullWriteStream();

    50     inline TUint BytesWritten();

    51 private:

    52     TNullBuf iSink;

    53     };

    54 

    55 inline TNullBuf::TNullBuf() : iBytesWritten(0) 

    56     {

    57     }

    58 

    59 inline TUint TNullBuf::BytesWritten() 

    60     {

    61     return iBytesWritten;

    62     }

    63 

    64 inline void TNullBuf::DoWriteL(const TAny*,TInt aLength)

    65     {

    66     iBytesWritten += aLength;

    67     }

    68 

    69 inline RNullWriteStream::RNullWriteStream()

    70     {

    71     Attach(&iSink);

    72     }

    73 

    74 inline TUint RNullWriteStream::BytesWritten()

    75     {

    76     return iSink.BytesWritten();

    77     }

    78 

    79 template <class T>

    80 TInt GetObjectSizeL(T* aObject)

    81     {

    82     TInt size(0);

    83     if(aObject)

    84         {

    85         RNullWriteStream nullstream;

    86         CleanupClosePushL(nullstream);

    87         nullstream << *aObject;

    88         nullstream.CommitL();

    89         size = nullstream.BytesWritten();

    90         CleanupStack::PopAndDestroy(&nullstream);

    91         return size;

    92         }

    93     return -1;

    94     }

    95 

    96 #endif //__APGCOMMONUTILS_H__