// 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;

 	}

 /**

 Quits the current compression operation and restarts with the specified arguments

 @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

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

 */

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

 	{

 	delete iBufferManager;

 	iBufferManager = NULL;

 	InitialiseBufManL(aRfs,aGzFileName,aInput,aBufferSize);

 	iCompressor->ResetL(*iBufferManager);

 	}

 /**

 Compresses the current file in stages.  The function needs to called again until the compression 

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

 @code

 while ( compressor->DeflateL() )

 	{

 	// No action required

 	}

 @endcode

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

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

 @return EFalse if the compression is finalised

 */

 EXPORT_C TBool CEZFileToGZip::DeflateL()

 	{

 	TBool keepgoing = iCompressor->DeflateL();

 	if (!keepgoing)

 		{

 		TEZGZipTrailer trailer(iBufferManager->Crc(), iUncompressedDataSize);

 		EZGZipFile::WriteTrailerL(iGZipFile, trailer);

 		iGZipFile.Close();

 		}

 	return keepgoing;

 	}

 void CEZFileToGZip::InitialiseBufManL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize)

 	{

 	User::LeaveIfError(aInput.Size(iUncompressedDataSize));

 	TInt err;

 	err = iGZipFile.Create(aRfs, aGzFileName,EFileStream | EFileWrite | EFileShareExclusive);

 	if (err == KErrAlreadyExists)

 		User::LeaveIfError(iGZipFile.Open(aRfs,aGzFileName,EFileStream | EFileWrite | EFileShareExclusive));

 	else 

 		User::LeaveIfError(err);

 	EZGZipFile::WriteHeaderL(iGZipFile,iHeader);

 	iBufferManager = CEZFileToGzipBM::NewL(aInput,iGZipFile,aBufferSize);

 	}

 void CEZFileToGZip::ConstructL(RFs &aRfs, const TDesC &aGzFileName, RFile &aInput, TInt aBufferSize)

 	{

 	InitialiseBufManL(aRfs,aGzFileName,aInput,aBufferSize);

 	// this is a special zlib modification to stop zlib writing out its normal zlib stream header.

 	iCompressor = CEZCompressor::NewL(*iBufferManager,CEZCompressor::EDefaultCompression,-CEZCompressor::EMaxWBits);

 	}