sl@0: // Copyright (c) 2003-2009 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: //
sl@0: 
sl@0: 
sl@0: #include <zipfile.h>
sl@0: #include <zipfilememberinputstream.h>
sl@0: #include "libzcore.h"
sl@0: 
sl@0: RZipFileMemberReaderStream::RZipFileMemberReaderStream(
sl@0:     CZipFile& aZipFile,
sl@0:     TUint32   aDataOffset,
sl@0:     TUint32   aCompressedSize,
sl@0:     TUint32   aUncompressedSize,
sl@0:     TUint32   aCompressionMethod):
sl@0:     iZipFile(aZipFile),
sl@0: 	iCompressionMethod(aCompressionMethod),
sl@0:     iCompressedSize(aCompressedSize),
sl@0:     iUncompressedSize(aUncompressedSize),
sl@0: 	iFileOffset(aDataOffset)
sl@0:     {    
sl@0:     }
sl@0: 
sl@0: 
sl@0: RZipFileMemberReaderStream* RZipFileMemberReaderStream::NewL(
sl@0: 	CZipFile& aZipFile,
sl@0:     TUint32   aDataOffset,
sl@0:     TUint32   aCompressedSize,
sl@0:     TUint32   aUncompressedSize,
sl@0:     TUint32   aCompressionMethod)
sl@0:     {    
sl@0: 	RZipFileMemberReaderStream* me = new(ELeave) RZipFileMemberReaderStream(aZipFile, aDataOffset, aCompressedSize,aUncompressedSize, aCompressionMethod);
sl@0: 	CleanupStack::PushL(me);
sl@0: 	me->ConstructL();
sl@0: 	CleanupStack::Pop(me);
sl@0: 	return me;		
sl@0:     }
sl@0: 
sl@0: /**
sl@0: Creates input stream to be used for reading the contents of the compressed file.
sl@0: */
sl@0: void RZipFileMemberReaderStream::ConstructL()
sl@0: 	{
sl@0: 	TInt err = inflateInit2_r(&iStream, -MAX_WBITS);
sl@0: 	if (err == Z_MEM_ERROR)
sl@0: 		{
sl@0: 		User::Leave(KErrNoMemory);
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Destructor. All dynamically allocated data structures for this stream are freed.
sl@0: */
sl@0: EXPORT_C RZipFileMemberReaderStream::~RZipFileMemberReaderStream()
sl@0: {
sl@0: 	inflateEnd_r(&iStream);
sl@0: }
sl@0: 
sl@0: /**
sl@0: Reads data from the stream buffer into the specified descriptor.
sl@0: On return, contains the data read from the stream buffer
sl@0: 
sl@0: @param aDes The target descriptor for the data read from the stream buffer
sl@0: @param aLength The maximum number of bytes to be read
sl@0: @return KErrNone If all bytes read successfully.
sl@0: @return	KErrCorrupt If reading fails.
sl@0: @return KErrEof If end of file is reached.
sl@0: @return ... Any one of the system-wide error codes for other errors.
sl@0: */
sl@0: EXPORT_C TInt RZipFileMemberReaderStream::Read(TDes16& aDes, TInt aLength)
sl@0: {
sl@0: 	TUint32 numBytesRead = 0;
sl@0: 	TInt err = Read(CONST_CAST(TByte*,(const TByte*)aDes.Ptr()), 2*aLength, &numBytesRead);
sl@0: 	if (err != KErrNone)
sl@0: 	{
sl@0: 		aDes.SetLength( (err==KErrEof) ? numBytesRead>>2 : 0 );
sl@0: 		return err;
sl@0: 	}
sl@0: 	
sl@0: 	aDes.SetLength(numBytesRead>>2);
sl@0: 	return KErrNone;
sl@0: }
sl@0: 
sl@0: TInt RZipFileMemberReaderStream::Read(void)
sl@0: 	{
sl@0: 	TByte b;
sl@0: 	TUint32 numRead = 0;
sl@0: 	
sl@0: 	if (Read(&b, 1, &numRead) == 1)
sl@0: 		{
sl@0: 		return b;
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		return -1;
sl@0: 		}
sl@0: 	}
sl@0: 	
sl@0: TInt RZipFileMemberReaderStream::Read(TDes8& aDes, TInt aLength)
sl@0: 	{
sl@0: 	TUint32 numBytesRead = 0;
sl@0: 	TInt err = Read(CONST_CAST(TByte*,aDes.Ptr()), aLength, &numBytesRead);
sl@0: 	if (err != KErrNone)
sl@0: 	{
sl@0: 		aDes.SetLength( (err==KErrEof) ? numBytesRead : 0 );
sl@0: 		return err;
sl@0: 	}
sl@0: 
sl@0: 	aDes.SetLength(numBytesRead);
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: void RZipFileMemberReaderStream::ReadL(TDes16& aDes, TInt aLength)
sl@0: 	{
sl@0: 	User::LeaveIfError(Read(aDes, aLength));
sl@0: 	}
sl@0: 
sl@0: void RZipFileMemberReaderStream::Release()
sl@0: {}
sl@0: 
sl@0: void RZipFileMemberReaderStream::Close()
sl@0: {}
sl@0: 
sl@0: 
sl@0: TInt RZipFileMemberReaderStream::Read(TByte* aBytes, TUint32 aLength, TUint32* aRetLength)
sl@0: 	{
sl@0: 	if (iCompressionMethod == CZipArchive::EDeflated)
sl@0: 		{
sl@0: 		return GetBytes(aBytes, aLength, aRetLength);
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		return GetStoredBytes(aBytes, aLength, aRetLength);
sl@0: 		}
sl@0: 	}
sl@0: 	
sl@0: TInt RZipFileMemberReaderStream::GetBytes(TByte* aBytes, TUint32 aLength, TUint32* aRetLength)
sl@0: 	{
sl@0: 	TUint32 bytesLeftToRead;
sl@0: 	TInt	status;
sl@0: 
sl@0: 	iBytesLength = 0;
sl@0: 
sl@0: 	// Be careful not to confuse compressed bytes and uncompressed bytes.
sl@0: 	// The length passed in is in uncompressed bytes, compressed bytes
sl@0: 	// are mainly used in the GetCompressedBytes() function called.
sl@0: 	// iBytesLength refers to the number of bytes already read.
sl@0: 	// If the request is to read past the end of the file
sl@0: 	// we should return KErrNone on the first instance, i.e. return all bytes
sl@0: 	// read successfully. On the second instance return KErrEof, i.e. we have 
sl@0: 	// already read all the bytes when another request comes in, so return KErrEof.
sl@0: 	// This follows the rules for reading an uncompressed file within this component
sl@0: 	// and this is also the way that RFile::ReadL() does it.
sl@0: 
sl@0: 	if (aLength > iUncompressedSize)
sl@0: 		{
sl@0: 		aLength = iUncompressedSize; // no point trying to read more than we have
sl@0: 		}
sl@0: 
sl@0: 	bytesLeftToRead = aLength;
sl@0: 
sl@0: 	while (bytesLeftToRead > 0) 
sl@0: 		{
sl@0: 		if (iStream.avail_in == 0)
sl@0: 			{
sl@0: 			if (GetCompressedBytes() != KErrNone)
sl@0: 				{
sl@0: 				return KErrCorrupt;
sl@0: 				}
sl@0: 			}
sl@0: 
sl@0: 		// The decompression will be done in the user provided memory.
sl@0: 		iStream.next_out = &aBytes[iBytesLength];
sl@0: 		iStream.avail_out = aLength - iBytesLength;
sl@0: 		status = inflate_r(&iStream, Z_SYNC_FLUSH);
sl@0: 
sl@0: 		switch (status)
sl@0: 			{
sl@0: 			case Z_OK:
sl@0: 				iBytesLength = aLength - iStream.avail_out;
sl@0: 				break;
sl@0: 				
sl@0: 			case Z_STREAM_END:	//EOF
sl@0: 				if (iBytesLength == aLength - iStream.avail_out)
sl@0: 					{
sl@0: 					*aRetLength = iBytesLength;
sl@0: 					return KErrEof;
sl@0: 					}
sl@0: 				else
sl@0: 					{
sl@0: 					iBytesLength = aLength - iStream.avail_out;
sl@0: 					break;
sl@0: 					}
sl@0: 			case Z_MEM_ERROR:
sl@0: 				return KErrNoMemory;
sl@0: 				
sl@0: 			default:
sl@0: 				return KErrCorrupt;
sl@0: 
sl@0: 			}
sl@0: 		bytesLeftToRead = aLength - iBytesLength;
sl@0: 		}
sl@0: 
sl@0: 	*aRetLength = iBytesLength;
sl@0: 	return KErrNone;
sl@0: 	}
sl@0: 
sl@0: TInt RZipFileMemberReaderStream::GetCompressedBytes(void)
sl@0: 	{
sl@0: 	if (iOffset < iCompressedSize)
sl@0: 		{
sl@0: 		TUint32	nBytesLeft;
sl@0: 		TUint32 nBytesToRead;
sl@0: 		
sl@0: 		nBytesLeft = iCompressedSize - iOffset;
sl@0: 		nBytesToRead = (nBytesLeft > sizeof(iCompressedBytes)) ? sizeof(iCompressedBytes) : nBytesLeft;
sl@0: 		if (iZipFile.Seek(iFileOffset) != KErrNone)
sl@0: 			{
sl@0: 			return KErrCorrupt; 
sl@0: 			}
sl@0: 		else
sl@0: 		if (iZipFile.Read(iCompressedBytes, nBytesToRead) != KErrNone)
sl@0: 			{
sl@0: 			return KErrCorrupt; 
sl@0: 			}
sl@0: 		iFileOffset += nBytesToRead;
sl@0: 		iOffset += nBytesToRead;
sl@0: 		iStream.next_in = iCompressedBytes;
sl@0: 		iStream.avail_in = nBytesToRead;
sl@0: 		return KErrNone;
sl@0: 		}
sl@0: 	else
sl@0: 	if (iDone == EFalse)
sl@0: 		{
sl@0: 		iCompressedBytes[0] = 0;
sl@0: 		iStream.avail_in = 1;
sl@0: 		iStream.next_in = iCompressedBytes;
sl@0: 		iDone = ETrue;
sl@0: 		return KErrNone;
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		return KErrCorrupt; 
sl@0: 		}
sl@0: 	}
sl@0: 	
sl@0: TInt RZipFileMemberReaderStream::GetStoredBytes(TByte* aBytes, TUint32 aLength, TUint32* aRetLength)
sl@0: 	{
sl@0: 	TInt status;
sl@0: 	
sl@0: 	if (aLength > iUncompressedSize)
sl@0: 		{
sl@0: 		aLength = iUncompressedSize; // no point trying to read more than we have
sl@0: 		}
sl@0: 	if (aLength == 0) // empty file like a directory
sl@0: 		{
sl@0: 		return KErrNone;
sl@0: 		}
sl@0: 	if (iOffset == iCompressedSize) // end of zip item.
sl@0: 		{
sl@0: 		return KErrEof; 
sl@0: 		}
sl@0: 	if ((iOffset + aLength) > iCompressedSize)
sl@0: 		{
sl@0: 		aLength = iCompressedSize - iOffset; // adjust read to what is left
sl@0: 		if ( aLength <= 0 )
sl@0: 			{
sl@0: 			return KErrCorrupt; 
sl@0: 			}
sl@0: 		}
sl@0: 	if (iZipFile.Seek(iFileOffset) != KErrNone)
sl@0: 		{
sl@0: 		return KErrCorrupt; 
sl@0: 		}
sl@0: 	status = iZipFile.Read(aBytes, aLength);
sl@0: 	if (status == KErrNone)
sl@0: 		{
sl@0: 		iFileOffset += aLength;
sl@0: 		iOffset += aLength;
sl@0: 		*aRetLength = aLength;
sl@0: 		}
sl@0: 	return status;
sl@0: 	}