// Copyright (c) 2003-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "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:

//

#include <ezgzip.h>

#include "libzcore.h"

const TUint8 EZGZipFile::ID1 = 31;

const TUint8 EZGZipFile::ID2 = 139;

/**

Constructor

*/

EXPORT_C TEZGZipHeader::TEZGZipHeader() : iId1(EZGZipFile::ID1), iId2(EZGZipFile::ID2), iCompressionMethod(8), iFlags(0), iTime(0), 

	iExtraFlags(0), iOs(255), iXlen(0), iExtra(NULL), iFname(NULL), iComment(NULL), iCrc(0)

	{

	}

/**

Destructor

*/

EXPORT_C TEZGZipHeader::~TEZGZipHeader()

	{

	delete iExtra;

	delete iFname;

	delete iComment;

	}

/**

Constructor

*/

EXPORT_C TEZGZipTrailer::TEZGZipTrailer() : iCrc32(0), iSize(0)

	{

	}

/**

Constructor

@param aCrc the CRC to use for archive checking

@param aSize the size of the trailer

*/

EXPORT_C TEZGZipTrailer::TEZGZipTrailer(TInt32 aCrc, TInt32 aSize) : iCrc32(aCrc), iSize(aSize)

	{

	}

//--------------------------------------------------------------------------------------------------------

/**

Read the zip header from the specified zip file into the TEZGZipHeader object

@param aFile the zip file to read from

@param aHeader the target header object

@leave KEZlibErrBadGZipHeader invalid zip header

@leave ... Any of the system wide error codes

*/

EXPORT_C void EZGZipFile::ReadHeaderL(RFile &aFile, TEZGZipHeader &aHeader)

	{

	TInt obligatoryData = sizeof(aHeader.iId1) + sizeof(aHeader.iId2) + sizeof(aHeader.iCompressionMethod) +

		sizeof(aHeader.iFlags) + sizeof(aHeader.iTime) + sizeof(aHeader.iExtraFlags) + sizeof(aHeader.iOs);

	TPtr8 des(&aHeader.iId1,0,obligatoryData);

	TInt err = aFile.Read(des);

	if (err != KErrNone || (des.Size() != obligatoryData))

		User::Leave(KEZlibErrBadGZipHeader);

	if (aHeader.iId1 != ID1 || aHeader.iId2 != ID2)

		User::Leave(KEZlibErrBadGZipHeader);

	if (aHeader.iFlags & (1 << EFExtra)) // then the extra bit is set

		{

		des.Set(REINTERPRET_CAST(TUint8 *,&aHeader.iXlen),0,sizeof(aHeader.iXlen));

		err = aFile.Read(des);

		if (err != KErrNone || des.Size() != sizeof(aHeader.iXlen) || aHeader.iXlen < 0)

			User::Leave(KEZlibErrBadGZipHeader);

		aHeader.iExtra = HBufC8::NewMaxL(aHeader.iXlen);

		TPtr8 des = aHeader.iExtra->Des();

		err = aFile.Read(des);

		if (err != KErrNone || des.Size() != aHeader.iXlen)

			User::Leave(KEZlibErrBadGZipHeader);

		}

	if (aHeader.iFlags & (1 << EFName)) // then read in filename

		ReadStringIntoDescriptorL(aFile,&aHeader.iFname);

	if (aHeader.iFlags & (1 << EFComment)) // then read in comment

		ReadStringIntoDescriptorL(aFile,&aHeader.iComment);

	if (aHeader.iFlags & (1 << EFHcrc))

		{

		des.Set(REINTERPRET_CAST(TUint8*,&aHeader.iCrc),0,sizeof(aHeader.iCrc));

		err = aFile.Read(des);

		if (err != KErrNone || des.Size() != sizeof(aHeader.iCrc))

			User::Leave(KEZlibErrBadGZipHeader);

		}

	}

/**

Write the zip header to the specified file

@param aFile the file to write to

@param aHeader the header object to write to the file

@leave ... Any of the system wide error codes

*/

EXPORT_C void EZGZipFile::WriteHeaderL(RFile &aFile, TEZGZipHeader &aHeader)

	{

	TInt obligatoryData = sizeof(aHeader.iId1) + sizeof(aHeader.iId2) + sizeof(aHeader.iCompressionMethod) +

		sizeof(aHeader.iFlags) + sizeof(aHeader.iTime) + sizeof(aHeader.iExtraFlags) + sizeof(aHeader.iOs);

	TPtrC8 des(&aHeader.iId1,obligatoryData);

	User::LeaveIfError(aFile.Write(des));

	TBuf8<1> null(1);

	null[0] = '\0';

	if (aHeader.iFlags & (1 << EFExtra)) // then the extra bit is set

		{

		des.Set(REINTERPRET_CAST(TUint8 *,&aHeader.iXlen),sizeof(aHeader.iXlen));

		User::LeaveIfError(aFile.Write(des));

		User::LeaveIfError(aFile.Write(*aHeader.iExtra));

		}

	if (aHeader.iFlags & (1 << EFName)) // then read in filename

		{

		User::LeaveIfError(aFile.Write(*aHeader.iFname));

		User::LeaveIfError(aFile.Write(null));

		}

	if (aHeader.iFlags & (1 << EFComment)) // then read in comment

		{

		User::LeaveIfError(aFile.Write(*aHeader.iComment));

		User::LeaveIfError(aFile.Write(null));

		}

	if (aHeader.iFlags & (1 << EFHcrc))

		{

		des.Set(REINTERPRET_CAST(TUint8*,&aHeader.iCrc),sizeof(aHeader.iCrc));

		User::LeaveIfError(aFile.Write(des));

		}

	}

void EZGZipFile::ReadStringIntoDescriptorL(RFile &aFile, HBufC8 **aDes)

	{

	TInt i, err;

	CArrayFixFlat<TUint8> *bytes = new (ELeave) CArrayFixFlat<TUint8>(16);

	CleanupStack::PushL(bytes);

	TBuf8<1> ch;

	while ((err = aFile.Read(ch)) == KErrNone)

		{

		if (ch.Length() != 1)

			User::Leave(KEZlibErrBadGZipHeader);

		else if (ch[0] != '\0')

			bytes->AppendL(*ch.Ptr());

		else

			break;

		}

	if (err != KErrNone)

		User::Leave(KEZlibErrBadGZipHeader);

	*aDes = HBufC8::NewMaxL(bytes->Count());

	for (i = 0; i < bytes->Count(); i++)

		(*aDes)->Des()[i] = (*bytes)[i];

	CleanupStack::PopAndDestroy(); // delete bytes

	}

/**

Read the zip trailer from the specified zip file into the TEZGZipTrailer object

@param aFile the zip file to read from

@param aTrailer the target trailer object

@leave KEZlibErrBadGZipTrailer invalid zip trailer

@leave ... Any of the system wide error codes

*/

EXPORT_C void EZGZipFile::ReadTrailerL(RFile &aFile, TEZGZipTrailer &aTrailer)

	{

	TPtr8 des(REINTERPRET_CAST(TUint8*,&aTrailer.iCrc32),0,sizeof(TEZGZipTrailer));

	TInt err = aFile.Read(des);

	if (err != KErrNone || des.Size() != sizeof(TEZGZipTrailer))

		User::Leave(KEZlibErrBadGZipTrailer);

	}

/**

Write the zip trailer to the specified file

@param aFile the file to write to

@param aTrailer the trailer object to write to the file

@leave ... Any of the system wide error codes

*/

EXPORT_C void EZGZipFile::WriteTrailerL(RFile &aFile, TEZGZipTrailer &aTrailer)

	{

	TPtrC8 des(REINTERPRET_CAST(TUint8*,&aTrailer.iCrc32),sizeof(TEZGZipTrailer));

	User::LeaveIfError(aFile.Write(des));

	}

/**

Find the zip trailer within the specified file, and read it into the TEZGZipTrailer object

@param aRfs file server session

@param aFname the file to read from

@param aTrailer the target trailer object

@leave KEZlibErrBadGZipHeader Invalid zip header

@leave ... Any of the system wide error codes

*/

EXPORT_C void EZGZipFile::LocateAndReadTrailerL(RFs &aRfs, const TDesC &aFname, TEZGZipTrailer &aTrailer)

	{

	TInt fileSize;

	RFile file;

	User::LeaveIfError(file.Open(aRfs,aFname,EFileStream | EFileRead | EFileShareAny));

	CleanupClosePushL(file);

	TUint8 magic[2];

	TPtr8 des(magic,0,sizeof(TUint8) * 2);

	User::LeaveIfError(file.Read(des));

	if (magic[0] != ID1 || magic[1] != ID2)

		User::Leave(KEZlibErrBadGZipHeader);

	User::LeaveIfError(file.Size(fileSize));

	TInt sizePos = fileSize - (sizeof (TInt32) * 2);

	User::LeaveIfError(file.Seek(ESeekStart,sizePos));

	des.Set(REINTERPRET_CAST(TUint8 *,&aTrailer),0,sizeof(TInt32)*2);

	User::LeaveIfError(file.Read(des));

	CleanupStack::PopAndDestroy();

	}

/**

@deprecated Interface is deprecated because it is unsafe as it may leave. It is available for backward compatibility reasons only.

@see EZGZipFile::IsGzipFileL

*/

EXPORT_C TBool EZGZipFile::IsGzipFile(RFs &aRfs, const TDesC &aFname)

	{

	TBool retBool = true;

	TRAPD(errCode, retBool = IsGzipFileL(aRfs, aFname));

	if(errCode != KErrNone)

		{

		retBool = false;

		}

	return retBool;

	}

/**

Determine if the given file is a valid zip file

@param aRfs file server session

@param aFname name of the file to check

@leave ... Any of the system wide error codes

@return ETrue if the file is valid zip file, EFalse otherwise

*/

EXPORT_C TBool EZGZipFile::IsGzipFileL(RFs &aRfs, const TDesC &aFname)

	{

	TUint8 ids[2];

	RFile file;

	User::LeaveIfError(file.Open(aRfs,aFname,EFileStream | EFileRead | EFileShareAny));

	CleanupClosePushL(file);

	TPtr8 des(ids,0,sizeof(TUint8) * 2);

	User::LeaveIfError(file.Read(des));

	CleanupStack::PopAndDestroy();

	return (ids[0] == ID1 && ids[1] == ID2);

	}

//--------------------------------------------------------------------------------------------------------

CEZFileToGzipBM::CEZFileToGzipBM(RFile &aInput, RFile &aOutput) : CEZFileBufferManager(aInput,aOutput)

	{

	iCrc = crc32_r(iCrc,NULL,0);

	}

CEZFileToGzipBM* CEZFileToGzipBM::NewLC(RFile &aInput, RFile &aOutput, TInt aBufferSize)

	{

	CEZFileToGzipBM *bm = new (ELeave) CEZFileToGzipBM(aInput,aOutput);

	CleanupStack::PushL(bm);

	bm->ConstructL(aBufferSize);

	return bm;

	}

CEZFileToGzipBM* CEZFileToGzipBM::NewL(RFile &aInput, RFile &aOutput, TInt aBufferSize)

	{

	CEZFileToGzipBM *bm = new (ELeave) CEZFileToGzipBM(aInput,aOutput);

	CleanupStack::PushL(bm);

	bm->ConstructL(aBufferSize);

	CleanupStack::Pop();

	return bm;

	}

void CEZFileToGzipBM::NeedInputL(CEZZStream &aZStream)

	{

	CEZFileBufferManager::NeedInputL(aZStream);

	iCrc = crc32_r(iCrc,iInputDescriptor.Ptr(),iInputDescriptor.Size());

	}

void CEZFileToGzipBM::InitializeL(CEZZStream &aZStream)

	{

	CEZFileBufferManager::InitializeL(aZStream);

	iCrc = crc32_r(iCrc,iInputDescriptor.Ptr(),iInputDescriptor.Size());

	}

//--------------------------------------------------------------------------------------------------------

CEZGzipToFileBM::CEZGzipToFileBM(RFile &aInput, RFile &aOutput) : CEZFileBufferManager(aInput,aOutput)

	{

	iCrc = crc32_r(iCrc,NULL,0);

	}

CEZGzipToFileBM* CEZGzipToFileBM::NewLC(RFile &aInput, RFile &aOutput, TInt aBufferSize)

	{

	CEZGzipToFileBM *bm = new (ELeave) CEZGzipToFileBM(aInput,aOutput);

	CleanupStack::PushL(bm);

	bm->ConstructL(aBufferSize);

	return bm;

	}

CEZGzipToFileBM* CEZGzipToFileBM::NewL(RFile &aInput, RFile &aOutput, TInt aBufferSize)

	{

	CEZGzipToFileBM *bm = new (ELeave) CEZGzipToFileBM(aInput,aOutput);

	CleanupStack::PushL(bm);

	bm->ConstructL(aBufferSize);

	CleanupStack::Pop();

	return bm;

	}

void CEZGzipToFileBM::NeedOutputL(CEZZStream &aZStream)

	{

	TPtrC8 od = aZStream.OutputDescriptor();

	iCrc = crc32_r(iCrc,od.Ptr(),od.Size());

	CEZFileBufferManager::NeedOutputL(aZStream);

	}

void CEZGzipToFileBM::FinalizeL(CEZZStream &aZStream)

	{

	TPtrC8 od = aZStream.OutputDescriptor();

	iCrc = crc32_r(iCrc,od.Ptr(),od.Size());

	CEZFileBufferManager::FinalizeL(aZStream);

	}

//--------------------------------------------------------------------------------------------------------

CEZGZipToFile::CEZGZipToFile() : iDecompressor(NULL), iBufferManager(NULL)

	{

	}

CEZGZipToFile::~CEZGZipToFile()

	{

	delete iDecompressor;

	delete iBufferManager;

	iGZipFile.Close();

	}

/**

Creates a new CEZGZipToFile object and leaves it on the CleanupStack

@param aRfs open file server session

@param aGzFileName name of the file to be de-compressed

@param aOutput the target file to hold the un-compressed data

@param aBufferSize required size of buffers

@return a pointer to the new CEZGZipToFile object, left on the CleanupStack

*/

EXPORT_C CEZGZipToFile* CEZGZipToFile::NewLC(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize)

	{

	CEZGZipToFile* dec = new (ELeave) CEZGZipToFile;

	CleanupStack::PushL(dec);

	dec->ConstructL(aRfs,aGzFileName,aOutput,aBufferSize);

	return dec;

	}

/**

Creates a new CEZGZipToFile object

@param aRfs open file server session

@param aGzFileName name of the file to be de-compressed

@param aOutput the target file to hold the un-compressed data

@param aBufferSize required size of buffers

@return a pointer to the new CEZGZipToFile object

*/

EXPORT_C CEZGZipToFile* CEZGZipToFile::NewL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize)

	{

	CEZGZipToFile* dec = new (ELeave) CEZGZipToFile;

	CleanupStack::PushL(dec);

	dec->ConstructL(aRfs,aGzFileName,aOutput,aBufferSize);

	CleanupStack::Pop();

	return dec;

	}

/**

Quits the current de-compression operation and restarts with the specified arguments

@param aRfs open file server session

@param aGzFileName name of the file to be de-compressed

@param aOutput the target file to hold the un-compressed data

@param aBufferSize required size of buffers

@leave ... Any of the system wide error codes

*/

EXPORT_C void CEZGZipToFile::ResetL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize)

	{

	delete iBufferManager;

	iBufferManager = NULL;

	InitialiseBufManL(aRfs,aGzFileName,aOutput,aBufferSize);

	iDecompressor->ResetL(*iBufferManager);

	}

/**

De-compresses the current zip file in stages.  The function needs to called again until the de-compression 

is finalised, in which case it will return EFalse - for example...

@code

while ( decompressor->InflateL() )

	{

	// No action required

	}

@endcode

@leave KEZlibErrBadGZipCrc Invalid CRC check

@leave ... Any of the system wide error codes

@return ETrue if the de-compression is not complete, and function must be called again

@return EFalse if the de-compression is finalised

*/

EXPORT_C TBool CEZGZipToFile::InflateL()

	{

	TBool keepGoing = iDecompressor->InflateL();

	if (!keepGoing)

		{

		if (iBufferManager->Crc() != iTrailer.iCrc32)

			{

			User::Leave(KEZlibErrBadGZipCrc);

			}

		iGZipFile.Close();

		}

	return keepGoing;

	}

void CEZGZipToFile::InitialiseBufManL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize)

	{

	EZGZipFile::LocateAndReadTrailerL(aRfs,aGzFileName,iTrailer);

	User::LeaveIfError(iGZipFile.Open(aRfs,aGzFileName,EFileStream | EFileRead | EFileShareAny));

	EZGZipFile::ReadHeaderL(iGZipFile,iHeader);

	iBufferManager = CEZGzipToFileBM::NewL(iGZipFile,aOutput,aBufferSize);

	}

void CEZGZipToFile::ConstructL(RFs &aRfs, const TDesC &aGzFileName, RFile &aOutput, TInt aBufferSize)

	{

	InitialiseBufManL(aRfs,aGzFileName,aOutput,aBufferSize);

	// this is a special zlib modification to stop it choking when it can't find the normal zlib stream header.

	iDecompressor = CEZDecompressor::NewL(*iBufferManager,-CEZDecompressor::EMaxWBits);

	}

//--------------------------------------------------------------------------------------------------------

CEZFileToGZip::CEZFileToGZip() : iCompressor(NULL), iBufferManager(NULL)

	{

	}

CEZFileToGZip::~CEZFileToGZip()

	{

	delete iCompressor;

	delete iBufferManager;

	iGZipFile.Close();

	}

/**

Creates a new CEZFileToGZip object and leaves it on the CleanupStack

@param aRfs open file server session

@param aGzFileName the name of the target zip file

@param aInput the file to compress

@param aBufferSize required size of buffers

@return a pointer to the new CEZFileToGZip object, left on the CleanupStack

*/

EXPORT_C CEZFileToGZip* CEZFileToGZip::NewLC(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize)

	{

	CEZFileToGZip* com = new (ELeave) CEZFileToGZip;

	CleanupStack::PushL(com);

	com->ConstructL(aRfs,aGzFileName,aInput,aBufferSize);

	return com;

	}

/**

Creates a new CEZFileToGZip object and leaves it on the CleanupStack

@param aRfs open file server session

@param aGzFileName the name of the target zip file

@param aInput the file to compress

@param aBufferSize required size of buffers

@return a pointer to the new CEZFileToGZip object, left on the CleanupStack

*/

EXPORT_C CEZFileToGZip* CEZFileToGZip::NewL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize)

	{

	CEZFileToGZip* com = new (ELeave) CEZFileToGZip;

	CleanupStack::PushL(com);

	com->ConstructL(aRfs,aGzFileName,aInput,aBufferSize);

	CleanupStack::Pop();

	return com;

	}