sl@0: // Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // Decompression buffer manager for GZip data
sl@0: //
sl@0: 
sl@0: #include <ezstream.h>
sl@0: #include "gzipbufmgr.h"
sl@0: //-----------------------------------------------------------------------------
sl@0: 
sl@0: // NOTE: This code was taken from the DeflateFilter (s60/DeflateFilter/)
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // StreamBufMgr::NewL
sl@0: // Two-phase constructor
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: GZipBufMgr* GZipBufMgr::NewL(TPtrC8 in)
sl@0:     {
sl@0:     GZipBufMgr* self = new (ELeave)GZipBufMgr(in);
sl@0:     CleanupStack::PushL(self);
sl@0:     self->ConstructL();
sl@0:     CleanupStack::Pop();
sl@0:     return self;
sl@0:     }//lint !e1746 const reference is not necessary here, because TPtrC8 takes only 4-bytes
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::GZipBufMgr
sl@0: // Constructor
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: GZipBufMgr::GZipBufMgr(TPtrC8 in)
sl@0:                     : iInput(in), iOutputDes(0, 0), iOutput(0),
sl@0:                       iNeedInput(EFalse), iNeedOutput(EFalse), 
sl@0:                       iFinalized(EFalse), iOffset(0), iID1(31), iID2(139)
sl@0:     {
sl@0:     } //lint !e1746
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::ConstructL
sl@0: // Initialize the output buffer
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::ConstructL()
sl@0:     {
sl@0:     // Output buffer and descriptor
sl@0:     iOutput = HBufC8::NewMaxL(1<<15);
sl@0:     iOutputDes.Set(iOutput->Des());
sl@0: 
sl@0:     // Setup the GZip header, this sets iOffset to after the header and start
sl@0:     // of the data
sl@0: 	TEZGZipHeader header;
sl@0:     ReadGZipHeaderL(header);
sl@0: 
sl@0:     // Move pass the header and set the buffer to the data
sl@0: 	TPtrC8 data(REINTERPRET_CAST(const TUint8*, iInput.Ptr() + iOffset), iInput.Length() - iOffset);
sl@0: 
sl@0:     // Setup the data buffer
sl@0: 	SetGZipBuffer(data);
sl@0: 
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::~GZipBufMgr
sl@0: // Destructor
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: GZipBufMgr::~GZipBufMgr()
sl@0:     {
sl@0:     delete iOutput;
sl@0:     iOutput = NULL;
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::InitializeL
sl@0: // Overriden function from MEZBufferManager
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::InitializeL(CEZZStream& aZStream)
sl@0:     {
sl@0:     // read more
sl@0:     aZStream.SetInput(iInput);
sl@0:     iOutputDes.SetLength(0);
sl@0:     aZStream.SetOutput(iOutputDes);
sl@0:     iNeedInput = EFalse;
sl@0:     iNeedOutput = EFalse;
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::NeedInputL
sl@0: // Overriden function from MEZBufferManager
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::NeedInputL(CEZZStream& /*aZStream*/)
sl@0:     {
sl@0:     //aZStream.SetInput(iInput);
sl@0:     iNeedInput = ETrue;
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::NeedOutputL
sl@0: // Overriden function from MEZBufferManager
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::NeedOutputL(CEZZStream& /*aZStream*/)
sl@0:     {
sl@0:     //aZStream.SetOutput(iOutputDes);
sl@0:     iNeedOutput = ETrue;
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::NeedOutputL
sl@0: // Overriden function from MEZBufferManager
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::FinalizeL(CEZZStream& /*aZStream*/)
sl@0:     {
sl@0:     // do nothing now, should check the checksum value here
sl@0:     // read the checksum value from the last chunk
sl@0:     //const TInt32* checksum = REINTERPRET_CAST(const TInt32*, iInput.Ptr() + (iInput.Length() - sizeof(TInt32)*2));
sl@0:     iFinalized = ETrue;
sl@0:     }
sl@0: 
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // Public methods
sl@0: // ----------------------------------------------------------------------------
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::ReadGZipHeaderL
sl@0: // Read the header of Gzip-ed stream in Gzip format, RFC1952.
sl@0: // Sets the iOffset pointer, which marks the end of the header and start of the
sl@0: // data.  This method needs to be called (or iOffset set) before calling
sl@0: // SetGZipBuffer method.
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::ReadGZipHeaderL(TEZGZipHeader& aHeader)
sl@0:     {
sl@0:     // construct a stream for reading
sl@0:     RMemReadStream memBuf;
sl@0:     memBuf.Open(iInput.Ptr(), iInput.Length());
sl@0:     
sl@0:     TInt obligatoryData = sizeof(aHeader.iId1) + sizeof(aHeader.iId2) +
sl@0:                           sizeof(aHeader.iCompressionMethod) +
sl@0:                           sizeof(aHeader.iFlags) + sizeof(aHeader.iTime) +
sl@0:                           sizeof(aHeader.iExtraFlags) + sizeof(aHeader.iOs);
sl@0:     
sl@0:     // copy the header data
sl@0:     TPtr8 des(&aHeader.iId1, 0, obligatoryData);
sl@0:     TRAPD(error, memBuf.ReadL(des));
sl@0:     
sl@0:     if (error == KErrEof)
sl@0:         {
sl@0:         User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:         }
sl@0:     
sl@0:     if (des.Size() < obligatoryData)
sl@0:         {
sl@0:         // should consider the situation when not enough data has arrived
sl@0:         User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:         }
sl@0:     
sl@0:     if (aHeader.iId1 != iID1 || aHeader.iId2 != iID2)
sl@0:         {
sl@0:         User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:         }
sl@0:     
sl@0:     if (aHeader.iFlags & (1 << EZGZipFile::EFExtra))
sl@0:         {
sl@0:         // The extra bit is set
sl@0:         des.Set(REINTERPRET_CAST(TUint8 *, &aHeader.iXlen), 0, sizeof(aHeader.iXlen));
sl@0:         memBuf.ReadL(des);
sl@0:         if (des.Size() != sizeof(aHeader.iXlen) || aHeader.iXlen < 0) //lint !e737 sign/unsigned doesn't realy matter here
sl@0:             {
sl@0:             User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:             }
sl@0:         
sl@0:         aHeader.iExtra = HBufC8::NewMaxL(aHeader.iXlen);
sl@0:         TPtr8 des1 = aHeader.iExtra->Des();
sl@0:         memBuf.ReadL(des1);
sl@0:         
sl@0:         if (des1.Size() != aHeader.iXlen)
sl@0:             {
sl@0:             User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:             }
sl@0:         }
sl@0:     
sl@0:     if (aHeader.iFlags & (1 << EZGZipFile::EFName))
sl@0:         {
sl@0:         // Read in filename
sl@0:         ReadStringIntoDescriptorL(memBuf, &aHeader.iFname);
sl@0:         }
sl@0:     
sl@0:     if (aHeader.iFlags & (1 << EZGZipFile::EFComment))
sl@0:         {
sl@0:         // Read in comment
sl@0:         ReadStringIntoDescriptorL(memBuf, &aHeader.iComment);
sl@0:         }
sl@0:     
sl@0:     if (aHeader.iFlags & (1 << EZGZipFile::EFHcrc))
sl@0:         {
sl@0:         des.Set(REINTERPRET_CAST(TUint8*, &aHeader.iCrc), 0, sizeof(aHeader.iCrc));
sl@0:         memBuf.ReadL(des);
sl@0:         if (des.Size() != sizeof(aHeader.iCrc)) //lint !e737 unsigned/signed doesn't matter
sl@0:             {
sl@0:             User::Leave(EZGZipFile::EBadGZipHeader);
sl@0:             }
sl@0:         }
sl@0:     
sl@0:     // Set iOffset to mark end of header and beginning of data
sl@0:     iOffset = memBuf.Source()->TellL(MStreamBuf::ERead).Offset();
sl@0:     
sl@0:     memBuf.Close();
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::ReadStringIntoDescriptorL
sl@0: // Read null-terminated strings into the buffer
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::ReadStringIntoDescriptorL(RMemReadStream& aMem, HBufC8 **aDes) const
sl@0:     {
sl@0:     TInt i;
sl@0:     CArrayFixFlat<TUint8> *bytes = new (ELeave) CArrayFixFlat<TUint8>(16);
sl@0:     CleanupStack::PushL(bytes);
sl@0:     TUint8 ch;
sl@0:     
sl@0:     while ((ch = aMem.ReadUint8L()) != '\0')
sl@0:         {
sl@0:         bytes->AppendL(ch);
sl@0:         }
sl@0:     
sl@0:     *aDes = HBufC8::NewMaxL(bytes->Count());
sl@0:     TPtr8 desPtr = (*aDes)->Des(); //lint because error #111 - separate desPtr used
sl@0:     
sl@0:     for (i = 0; i < bytes->Count(); i++)
sl@0:         {
sl@0:         desPtr[i] = (*bytes)[i]; //lint !e1058 force conversion here
sl@0:         }
sl@0:     
sl@0:     CleanupStack::PopAndDestroy(); // delete bytes	
sl@0:     }
sl@0: 
sl@0: // ----------------------------------------------------------------------------
sl@0: // GZipBufMgr::SetBuffer
sl@0: // Set the input buffer
sl@0: // ----------------------------------------------------------------------------
sl@0: //
sl@0: void GZipBufMgr::SetGZipBuffer(TPtrC8 data)
sl@0:     {
sl@0:     iInput.Set(data);
sl@0:     }//lint !e1746