/*

* 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 

 @internalComponent

 @released

*/

#ifdef _MSC_VER

#pragma warning (disable: 4786)

#endif // _MSC_VER

#include "siswrite.h"

#include "utility_interface.h"

#include <zlib.h>

bool CompressData (	const TUint8* aInputData, const CSISFieldRoot::TFieldSize aInputSize,

					TUint8*& aOutputData, CSISFieldRoot::TFieldSize& aOutputSize,

					const bool aCanAbandon)

	{

	assert (aOutputData == NULL);

	assert (aInputData != NULL);

	assert (! IsBadReadPtr (aInputData, aInputSize));

	CSISFieldRoot::TFieldSize inputSize = aInputSize;

	inputSize = inputSize + (inputSize / 64) + 16;

		// see zlib library documentation for the reasons for this calculation

	TUint8* buffer = new TUint8 [inputSize];

	try

		{

		z_stream compressionState;

		memset (&compressionState, 0, sizeof (z_stream));

		compressionState.avail_out = inputSize;

		compressionState.data_type = Z_BINARY;

		compressionState.avail_in = aInputSize;

		compressionState.next_out = buffer;

		compressionState.next_in = const_cast <Bytef*> (aInputData);

		try 

			{

			CSISException::ThrowIf (deflateInit (&compressionState, Z_DEFAULT_COMPRESSION) != Z_OK,

									CSISException::ECompress,

									"deflation progress");

			CSISException::ThrowIf (deflate (&compressionState, Z_FINISH) != Z_STREAM_END,

									CSISException::ECompress,

									"deflation end");

			}

		catch (...)

			{

			deflateEnd (&compressionState);

			throw;

			}

		deflateEnd (&compressionState);

		aOutputData = buffer;

		aOutputSize = static_cast <CSISFieldRoot::TFieldSize> (compressionState.total_out);

		}

	catch (...) 

		{

		delete [] buffer;

		aOutputData = NULL;

		aOutputSize = 0;

		throw;

		}

	if ((aOutputSize < aInputSize) || ! aCanAbandon)

		{

		return true;

		}

	delete [] buffer;

	aOutputData = NULL;

	aOutputSize = 0;

	return false;

	}

void ExpandStream (const TUint8* aInputData, const CSISFieldRoot::TFieldSize aInputSize, TSISStream& stream)

	{

	assert (aInputData != NULL);

	assert (! IsBadReadPtr (aInputData, aInputSize));

	z_stream compressionState;

	memset (&compressionState, 0, sizeof (z_stream));

	const uLong arbitraryBufferSize (262144);

	TSISStream::pos_type start = stream.tell ();

	TUint8* buffer = new TUint8 [arbitraryBufferSize];

	try 

		{

		compressionState.avail_in = aInputSize;

		compressionState.next_in = const_cast <Bytef*> (aInputData);

		compressionState.avail_out = arbitraryBufferSize;

		compressionState.next_out = buffer;

		compressionState.data_type = Z_BINARY;

		CSISException::ThrowIf (inflateInit (&compressionState) != Z_OK,

								CSISException::ECompress,

								"inflation initialisation");

		int status;

		while ((status = inflate (&compressionState, Z_NO_FLUSH)) == Z_OK)

			{

			stream.write (buffer, arbitraryBufferSize - compressionState.avail_out);

			compressionState.avail_out = arbitraryBufferSize;

			compressionState.next_out = buffer;

			}

		CSISException::ThrowIf (status != Z_STREAM_END,

								CSISException::ECompress,

								"inflation");

		status = inflate (&compressionState, Z_FINISH);

		CSISException::ThrowIf (status != Z_STREAM_END,

								CSISException::ECompress,

								"inflation");

		stream.write (buffer, arbitraryBufferSize - compressionState.avail_out);

		}

	catch (...)

		{

		inflateEnd (&compressionState);

		delete [] buffer;

		stream.seek (start);

		throw;

		}

	inflateEnd (&compressionState);

	delete [] buffer;

	}