/*

 * Copyright (c) 1998-2009 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: 

 * This file contains the implementation of the ASN1 integer class.

 * As noted in Notes.txt there are two approaches to the storage of data by

 * this class, it can either hold a copy of the data or a pointer to something

 * else which holds a copy of the data.

 * The object contained within this file encapsulates the ASN1 integer object

 * as described in X208 section 14 and the encoding described in X209 section

 * 8. 

 *

 */

 #include "asn1dec.h"

 #include <bigint.h>

 EXPORT_C TASN1DecInteger::TASN1DecInteger()

 	{

 	}

 EXPORT_C TInt TASN1DecInteger::DecodeDERShortL(const TDesC8& aSource,TInt& aPos)

 	{

 	TPtrC8 Source=aSource.Mid(aPos);

 	TASN1DecGeneric gen(Source);

 	gen.InitL();

 	TInt res = DecodeDERShortL(gen);

 	aPos+=gen.LengthDER();

 	return res;

 	}

 EXPORT_C TInt TASN1DecInteger::DecodeDERShortL(const TASN1DecGeneric& aSource)

 	{

 	TInt res = 0;

 	TPtrC8 ptr(aSource.GetContentDER());

 	//stop stupid compiler warning

 	TUint length = (TUint)(ptr.Length());

 	if (length == 0) // DEF055722 

 		{

 		User::Leave(KErrArgument);

 		}

 	if (length > sizeof(TInt))

 		{

 		User::Leave(KErrTooBig);

 		}

 	TInt8 i;

 	if (ptr[0]&128)

 		{

 		res = -1;

 		}

 	for (i=0;i<ptr.Length();i++)

 		{

 		res<<=8;

 		res+=ptr[i];

 		}

 	return res;

 	}

 EXPORT_C RInteger TASN1DecInteger::DecodeDERLongL(const TDesC8& aSource,TInt& aPos)

 	{

 	TPtrC8 Source=aSource.Right(aSource.Length() - aPos);

 	TASN1DecGeneric gen(Source);

 	gen.InitL();

 	RInteger res = DecodeDERLongL(gen);

 	aPos+=gen.LengthDER();

 	return res;

 	}

 EXPORT_C RInteger TASN1DecInteger::DecodeDERLongL(const TASN1DecGeneric& aSource)

 	{

 	const TDesC8& data = aSource.GetContentDER();

 //	JCS 14/03/2003: Changed call to NewL from NewSignedL() because current

 //	problem in RInteger for signed code means this sometimes returns incorrect

 //	results causing failure in certstore testcode.  However, making this change

 //	does cause problems in TASN1 now (posted defect DEF021796).

 	RInteger res = RInteger::NewL(data);//aSource.GetContentDER());

 	return (res);

 	}