sl@0: // Copyright (c) 2006-2009 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 <assert.h>
sl@0: #include <pcstore/storeexception.h>
sl@0: #include "filestreambuf.h"
sl@0: 
sl@0: namespace PCStore
sl@0: {
sl@0: /**
sl@0: Constructs a file stream buffer object with the specified file name and open mode.
sl@0: 
sl@0: Opens the file in specified read/write mode.
sl@0: 
sl@0: @param aFileName The name of the file which the file stream buffer will open and access.
sl@0: @param aMode The mode in which the file would be opened.
sl@0: @exception TStoreException::EFileOpenError Error occurs in file opening.
sl@0: */
sl@0: CFileStreamBuf::CFileStreamBuf(const char* aFileName, TFileMode aMode)
sl@0: 	:iFile(NULL), iStreamOpened(false)
sl@0: 	{
sl@0: 	if(aMode == EWriteFile) 
sl@0: 		{
sl@0: 		iFile=fopen(aFileName,"wb");
sl@0: 		}
sl@0: 	else
sl@0: 		{
sl@0: 		iFile=fopen(aFileName,"rb");
sl@0: 		}
sl@0: 	if(iFile == NULL) 
sl@0: 		{
sl@0: 		throw TStoreException(TStoreException::EFileOpenError);
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Destructor.
sl@0: Closes the file.
sl@0: */
sl@0: CFileStreamBuf::~CFileStreamBuf()
sl@0: 	{
sl@0: 	fclose(iFile);
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Flags that a stream with the specified stream id is opened.
sl@0: 
sl@0: Checks whether a stream has been opened. If not, moves the file pointer to the position 
sl@0: which is represented by the given stream id, and sets the stream open flag to TRUE. If a 
sl@0: stream has been opened, throws an exception.
sl@0: 
sl@0: This function is called by the constructor of CStoreReadStream and CStoreWriteStream
sl@0: to flag the new stream is opened. 
sl@0: 
sl@0: @param aStreamId The stream id of the open stream.
sl@0: @exception TStoreException::EStreamExclusionError Another stream is still opened.
sl@0: @exception TStoreException::EFileSeekError Error occurs when seeking within the file 
sl@0: due to an incorrect stream id or other reason.
sl@0: */
sl@0: void CFileStreamBuf::StreamOpen(TStreamId aStreamId)
sl@0: 	{
sl@0: 	//check the opened stream
sl@0: 	if(iStreamOpened)
sl@0: 		{
sl@0: 		throw TStoreException(TStoreException::EStreamExclusionError);
sl@0: 		}
sl@0: 	// set pointer to the correct position
sl@0: 	TInt ret = fseek(iFile,aStreamId.Value(),SEEK_SET);  
sl@0: 	if(ret)
sl@0: 		{
sl@0: 		throw TStoreException(TStoreException::EFileSeekError);
sl@0: 		}
sl@0: 
sl@0: 	iStreamOpened = true;
sl@0: 	}
sl@0: 
sl@0: /** 
sl@0: Flags that the opened stream is closed.
sl@0: 
sl@0: This function is called by the destructor of the CStoreReadStream and CStoreWriteStream 
sl@0: to indicate the stream is being closed.
sl@0: */
sl@0: void CFileStreamBuf::StreamClose()
sl@0: 	{
sl@0: 	iStreamOpened = false;
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Gets a new stream id which will be used to create a write stream.
sl@0: 
sl@0: The new stream id is the end position of the store file.
sl@0: 
sl@0: Moves the read/write pointer to the end to the file to get the stream id.
sl@0: 
sl@0: @return The new stream id.
sl@0: @exception TStoreException::EStreamExclusionError Another stream is still opened.
sl@0: @exception TStoreException::EFileSeekError Error occurs when the file pointer is moved to 
sl@0: the end of file.
sl@0: */	
sl@0: TStreamId CFileStreamBuf::GetNewStreamId()
sl@0: 	{
sl@0: 	//check the opened stream
sl@0: 	if(iStreamOpened)
sl@0: 		{
sl@0: 		throw TStoreException(TStoreException::EStreamExclusionError);
sl@0: 		}
sl@0: 	// move pointer to the end of the file
sl@0: 	TInt ret = fseek(iFile,0,SEEK_END);  
sl@0: 	if(ret) 
sl@0: 		{
sl@0: 		throw TStoreException(TStoreException::EFileSeekError);
sl@0: 		}
sl@0: 
sl@0: 	TUint size = ftell(iFile);
sl@0: 	TStreamId id = size;
sl@0: 	return id;
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Reads the specified length of 8-bit data to the supplied buffer from the file.
sl@0: 
sl@0: Assert aLength must not be negative and aPtr must not be NULL.
sl@0: 
sl@0: @param aPtr The pointer to the buffer to receive the read data.
sl@0: @param aLength The length of the data to read.
sl@0: @exception TStoreException::EFileReadError Error occurs in data reading.
sl@0: */
sl@0: void CFileStreamBuf::Read(const TUint8* aPtr, TInt32 aLength)
sl@0: 	{
sl@0: 	assert(aLength >= 0 && aPtr != NULL);
sl@0: 	if (aLength > 0) 
sl@0: 		{
sl@0: 		size_t numRead;
sl@0: 		numRead = fread(reinterpret_cast<void*>(const_cast<TUint8*>(aPtr)),\
sl@0: 			sizeof(TUint8), aLength, iFile);
sl@0: 		if(numRead < static_cast<TUint32>(aLength))
sl@0: 			{
sl@0: 			throw TStoreException(TStoreException::EFileReadError);
sl@0: 			}
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: /**
sl@0: Writes the specified length of 8-bit data from the supplied buffer to the file.
sl@0: 
sl@0: Assert aLength must not be negative and aPtr must not be NULL.
sl@0: 
sl@0: @param aPtr The pointer to the buffer holding the written data.
sl@0: @param aLength The length of the data to write.
sl@0: @exception TStoreException::EFileWriteError Error occurs in data writing.
sl@0: */
sl@0: void CFileStreamBuf::Write(const TUint8* aPtr, TInt32 aLength)
sl@0: 	{
sl@0: 	assert(aLength >= 0 && aPtr != NULL);	
sl@0: 	if (aLength > 0)
sl@0: 		{
sl@0: 		size_t numWritten ;
sl@0: 		numWritten  = fwrite(reinterpret_cast<void*>(const_cast<TUint8*>(aPtr)),\
sl@0: 			sizeof(TUint8), aLength, iFile);
sl@0: 		if(numWritten < static_cast<TUint32>(aLength))
sl@0: 			{
sl@0: 			throw TStoreException(TStoreException::EFileWriteError);
sl@0: 			}
sl@0: 		}
sl@0: 	}
sl@0: }