/*

 * Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of the License "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: 

 *

 */

 /**

  @file

  @internalTechnology

 */

 #include "filecompare.h"

 #include "cryptospi/cryptospidef.h"

 #include <e32std.h>

 #include <e32def.h>

 #include <f32file.h>

 const TInt KCompareBlockSize = 0xff;

 //const TInt KCompareEqual = 0;

 const TInt KCompareGreaterThan = 1;

 const TInt KCompareLessThan = -1;

 // a simple utility class to compare 2 files, returns

 TInt TFileCompare::CompareL(TPtrC aFile1Path, TPtrC aFile2Path)

 	{

 	// assume is all well, compare always 

 	TInt retVal = 0;

 	RFs 	rFs;

 	RFile	file1;

 	RFile	file2;

 	User::LeaveIfError(rFs.Connect());

 	CleanupClosePushL(rFs);

 	User::LeaveIfError(file1.Open(rFs, aFile1Path, EFileRead));

 	CleanupClosePushL(file1);

 	User::LeaveIfError(file2.Open(rFs, aFile2Path, EFileRead));

 	CleanupClosePushL(file2);

 	TInt file1Size;

 	file1.Size(file1Size); 

 	TInt file2Size;

 	file2.Size(file2Size);

 	// bail out if the sizes of the 2 files are different

 	if(file1Size == file2Size)

 		{

 		TBuf8<KCompareBlockSize> tempBuf1;

 		TBuf8<KCompareBlockSize> tempBuf2;

 		TInt compareBlockSize;

 		TInt loopCount;

 		if(file1Size > KCompareBlockSize)

 		{

 			compareBlockSize = KCompareBlockSize;

 			loopCount = file1Size / compareBlockSize;

 		}

 		else

 		{

 			loopCount = 1;

 			compareBlockSize = file1Size;

 		}

 		// read through the files comparing each block

 		for(TInt i = 0; i < loopCount; i++)

 			{

 			file1.Read(tempBuf1, compareBlockSize);

 			file2.Read(tempBuf2, compareBlockSize);

 			// remember, 0 is return value for a successful comparison

 			retVal = tempBuf1.Compare(tempBuf2);

 			if( retVal != 0 )

 				{

 				//if files fail to match, break out of the loop

 				break;

 				}		

 			}

 		}

 	else

 		{

 		if(file1Size > file2Size)

 			retVal = KCompareGreaterThan;

 		else

 			retVal = KCompareLessThan;

 		}

 	CleanupStack::PopAndDestroy(&file2);

 	CleanupStack::PopAndDestroy(&file1);

 	CleanupStack::PopAndDestroy(&rFs);

 	return retVal;		

 	}