// Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// which accompanies this distribution, and is available

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

//

// Class TStreamMark

inline TStreamMark::TStreamMark()

	: iPos(KStreamBeginning-1)

/** Constructs a default shared stream mark object.

The position for the mark is uninitialised.

An uninitialised mark means that a call to IsEmpty() returns true.

@see IsEmpty() */

	{}

inline TStreamMark::TStreamMark(TStreamPos aPos)

	: iPos(aPos)

/** Constructs the shared stream mark object, setting the mark to the specified 

stream position.

An initialised mark means that a call to IsEmpty() returns false.

@param aPos The stream position

@see IsEmpty() */

	{

#if defined (_DEBUG)

	__DbgChkPos(aPos);

#endif

	}

inline TStreamMark& TStreamMark::operator=(TStreamPos aPos)

/** Assigns the specified stream position value to this shared stream mark object.

@param aPos The stream position value to be assigned.

@return A reference to this shared stream mark object. */

	{

#if defined (_DEBUG)

	__DbgChkPos(aPos);

#endif

	iPos=aPos;

	return *this;

	}

inline TStreamMark::operator TStreamMark*()

	{return this;}

inline TStreamMark::operator const TStreamMark*() const

	{return this;}

inline TBool TStreamMark::operator==(const TStreamMark& aMark) const

/** Tests whether this object and the specified referenced shared stream mark object 

are the same object.

@param aMark A reference to a shared stream mark object.

@return True, if the two objects are the same object; false, otherwise. */

	{return this==&aMark;}

inline TBool TStreamMark::operator==(const TStreamMark* aPtr) const

	{return this==aPtr;}

inline TBool TStreamMark::operator!=(const TStreamMark& aMark) const

/** Tests whether this object and the specified shared stream mark object are different 

objects.

@param aMark A pointer to a shared stream mark object.

@return True, if the two objects are different objects; false, otherwise. */

	{return this!=&aMark;}

inline TBool TStreamMark::operator!=(const TStreamMark* aPtr) const

	{return this!=aPtr;}

inline TBool TStreamMark::IsEmpty() const

/** Tests whether this mark object is uninitialised.

@return True, if this mark object is uninitialised; false, otherwise. */

	{return iPos<KStreamBeginning;}

inline void TStreamMark::Clear()

/** Resets the mark object to its default state.

On return from this function, the mark is uninitialised and a call to IsEmpty() 

returns true.

Empties the object/makes it empty so that IsEmpty() returns false */

	{iPos=KStreamBeginning-1;}

inline TStreamPos TStreamMark::Position() const

/** Gets the position of the mark.

@return The stream position. */

	{

#if defined (_DEBUG)

	__DbgChkPos(iPos);

#endif

	return iPos;

	}

inline TBool TStreamMark::IsWith(TStreamExchange& aHost) const

/** Tests whether the specified shared streaming manager currently refers to this 

mark object.

@param aHost The object that manages shared streaming.

@return True, if the shared stream manager refers to this mark; false, otherwise. */

	{return aHost.RefersTo(*this);}

inline TBool TStreamMark::RelatesTo(TStreamExchange& aHost) const

/** Tests whether the specified shared streaming manager currently refers to this 

mark object OR whether this mark object is initialised.

@param aHost The object that manages shared streaming.

@return True, if the shared stream manager refers to this mark OR if this mark 

object is initialised; false, otherwise.

@see IsWith()

@see TStreamExchange::IsActive() */

	{return iPos>=KStreamBeginning||aHost.RefersTo(*this);}

inline void TStreamMark::Withdraw(TStreamExchange& aHost)

/** Instructs the shared streaming manager to remove any reference it has to this 

mark object.

@param aHost The object that manages shared streaming. */

	{aHost.Drop(*this);}

inline void TStreamMark::ExtractL(TStreamExchange& aHost)

/** Refreshes this mark from the mark in the host stream buffer and tells the shared 

streaming manager to drop any reference it has to to this mark object.

@param aHost The object that manages shared streaming. */

	{aHost.GetL(*this);}

inline TInt TStreamMark::ReadL(TStreamExchange& aHost,TAny* aPtr,TInt aMaxLength)

/** Reads data from the shared stream into the specified memory location.

@param aHost The object that manages shared streaming.

@param aPtr A pointer to the target memory location for the data read from 

the shared stream.

@param aMaxLength The maximum number of bytes to be read.

@return The number of bytes read. */

	{return aHost.DoReadL(aPtr,aMaxLength,*this);}

inline TInt TStreamMark::ReadL(TStreamExchange& aHost,TDes8& aDes,TInt aMaxLength,TRequestStatus& aStatus)

/** Reads data, asynchronously, from the shared stream into the specified descriptor.

If the function leaves, then no read request will have been initiated.

@param aHost The object that manages shared streaming.

@param aDes The target descriptor for the data read from the shared stream.

@param aMaxLength The maximum number of bytes to be read.

@param aStatus The request status that indicates the completion status of this 

asynchronous request.

@return The maximum number of bytes to be read, as used in this request. This 

can be different to the value supplied in aMaxLength; this is dependent on 

the implementation of the underlying stream. */

	{return aHost.DoReadL(aDes,aMaxLength,aStatus,*this);}

inline TStreamTransfer TStreamMark::ReadL(TStreamExchange& aHost,MStreamInput& anInput,TStreamTransfer aTransfer)

/** Reads data from the shared stream into the specified data sink.

@param aHost The object that manages shared streaming.

@param anInput The sink which is the target for the read operation.

@param aTransfer Defines the amount of data available to be read from the shared 

stream.

@return The amount of data that was not consumed. */

	{return aHost.DoReadL(anInput,aTransfer,*this);}

inline TInt TStreamMark::ReadL(TStreamExchange& aHost,MStreamInput& anInput,TInt aMaxLength)

/** Reads data from the shared stream into the specified data sink.

@param aHost The object that manages shared streaming.

@param anInput The sink which is the target for the read operation.

@param aMaxLength The maximum amount of data available to be read from the 

shared stream.

@return The amount of data that was not consumed. */

	{return aMaxLength-aHost.DoReadL(anInput,TStreamTransfer(aMaxLength),*this).Left();}

inline void TStreamMark::ReadL(TStreamExchange& aHost,MStreamInput& anInput)

/** Reads data from the shared stream into the specified data sink.

No explicit limit is placed on the amount of data that can be read.

@param aHost The object that manages shared streaming.

@param anInput The sink which is the target for the read operation. */

	{aHost.DoReadL(anInput,KStreamUnlimited,*this);}

inline void TStreamMark::WriteL(TStreamExchange& aHost,const TAny* aPtr,TInt aLength)

/** Writes data from the specified memory location into the shared stream.

@param aHost The object that manages shared streaming.

@param aPtr A pointer to the memory location from which data is to be written 

to the shared stream.

@param aLength The number of bytes to be written. */

	{aHost.DoWriteL(aPtr,aLength,*this);}

inline TInt TStreamMark::WriteL(TStreamExchange& aHost,const TDesC8& aDes,TInt aMaxLength,TRequestStatus& aStatus)

/** Writes data, asynchronously, from the specified descriptor into the shared 

stream.

If the function leaves, then no write request will have been initiated.

@param aHost The object that manages shared streaming.

@param aDes The source descriptor for the data to be written into the shared 

stream.

@param aMaxLength The maximum number of bytes to be written.

@param aStatus The request status that indicates the completion status of this 

asynchronous request.

@return The maximum number of bytes to be written, as used in this request. 

This can be different to the value supplied in aMaxLength; this is dependent 

on the implementation. */

	{return aHost.DoWriteL(aDes,aMaxLength,aStatus,*this);}

inline TStreamTransfer TStreamMark::WriteL(TStreamExchange& aHost,MStreamOutput& anOutput,TStreamTransfer aTransfer)

/** Writes data into the shared stream from the specified data source.

@param aHost The object that manages shared streaming.

@param anOutput The data source for the write operation.

@param aTransfer Defines the amount of data to be pulled from the output stream 

object.

@return A stream transfer object defining the amount of data that was not consumed. */

	{return aHost.DoWriteL(anOutput,aTransfer,*this);}

inline TInt TStreamMark::WriteL(TStreamExchange& aHost,MStreamOutput& anOutput,TInt aMaxLength)

/** Writes data into the shared stream from the specified data source

@param aHost The object that manages shared streaming.

@param anOutput The data source for the write operation.

@param aMaxLength The maximum amount of data available to be written.

@return The amount of data that was not consumed. */

	{return aMaxLength-aHost.DoWriteL(anOutput,TStreamTransfer(aMaxLength),*this).Left();}

inline void TStreamMark::WriteL(TStreamExchange& aHost,MStreamOutput& anOutput)

/** Writes data into the shared stream from the specified data source.

No explicit limit is placed on the amount of data that can be written.

@param aHost The object that manages shared streaming.

@param anOutput The data source for the write operation. */

	{aHost.DoWriteL(anOutput,KStreamUnlimited,*this);}

inline void TStreamMark::SeekL(TStreamExchange& aHost,TStreamPos aPos)

	{aHost.DoSeekL(*this,EStreamBeginning,aPos.Offset());}

inline TStreamPos TStreamMark::SeekL(TStreamExchange& aHost,TStreamLocation aLocation,TInt anOffset)

/** Moves the position of the mark in the host stream.

The new position is calculated by adding the specified offset to one of:

the position of the beginning of the host stream

the position of the end of the host stream

the position of the current mark.

@param aHost The object that manages shared streaming.

@param aLocation The location in the host stream on which the calculation of 

the new position is based.

@param anOffset The offset value.

@return The new position of the mark. */

	{return aHost.DoSeekL(*this,aLocation,anOffset);}

inline TStreamPos TStreamMark::SeekL(TStreamExchange& aHost,TInt anOffset)

/** Moves the position of the mark in the host stream.

@param aHost The object that manages shared streaming.

@param anOffset The amount by which the position of the mark is to be moved 

relative to the existing position of the mark.

@return The new position of the mark. */

	{return aHost.DoSeekL(*this,EStreamMark,anOffset);}

inline TStreamPos TStreamMark::TellL(TStreamExchange& aHost) const

/** Gets the position of the mark within the host stream.

@param aHost The object that manages shared streaming.

@return The stream position. */

	{return aHost.DoSeekL(CONST_CAST(TStreamMark&,*this),EStreamMark,0);}

// Class TStreamExchange

inline TStreamExchange::TStreamExchange()

	: iHost(NULL),iRMrk(NULL),iWMrk(NULL)

/** Constructs an empty object.

Call Share() to prepare for access to a shared stream buffer. */

	{}

inline TStreamExchange::TStreamExchange(MStreamBuf* aHost)

	: iHost(aHost),iRMrk(NULL),iWMrk(NULL)

/** Constructs the object, specifying the stream buffer that will act as the shared 

host.

@param aHost A pointer to a stream buffer that will act as the shared host. */

	{}

inline void TStreamExchange::Share(MStreamBuf* aHost)

/** Tells the object to use the specified stream buffer that will act as the shared 

host.

@param aHost A pointer to a stream buffer that will act as the shared host. */

	{iHost=aHost;}

inline TBool TStreamExchange::IsActive() const

/** Tests whether this object is using a stream buffer that is acting as shared 

host.

@return True, if this object is using a shared host ; false, otherwise. */

	{return iHost!=NULL;}

// Class RShareBuf

inline void RShareBuf::Open(TStreamExchange& aHost,TInt aMode)

/** Prepares the shared stream buffer for streaming.

The function sets the read mark and/or the write mark to the beginning of 

the host stream.

@param aHost The object that manages shared streaming.

@param aMode The streaming mode. This can be read and/or write, as indicated 

by the ERead and EWrite bits.

@see MStreamBuf::TRead

@see MStreamBuf::TWrite

@see KStreamBeginning */

	{Open(aHost,KStreamBeginning,aMode);}

// Class RShareWriteStream

inline RShareWriteStream::RShareWriteStream(const MExternalizer<TStreamRef>& anExter)

	: RWriteStream(anExter)

	{}