// Copyright (c) 1994-2009 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:

// RWsBuffer class, handles buffering and flushing of window server commands

// 

//

#include <e32std.h>

#include "../SERVER/w32cmd.h"

#include "CLIENT.H"

#include "w32comm.h"

// Global functions

GLDEF_C void Assert(TW32Assert aAssert)

	{

	_LIT(KW32AssertCategory,"W32 Assert");

	User::Panic(KW32AssertCategory,aAssert);

	}

GLDEF_C void Panic(TW32Panic aPanic)

	{

	_LIT(KW32PanicCategory,"W32");

	User::Panic(KW32PanicCategory,aPanic);

	}

// Public functions

RWsBuffer::RWsBuffer(RWsSession *aSession) : iSession(aSession), iManager(NULL),

	#if defined(__AUTO_FLUSH)

		iAutoFlush(ETrue),

	#else

		iAutoFlush(EFalse),

	#endif

	iBuf(NULL,0,0), iNext(NULL), iPreviousHandle(0), iBufSize(0), iMaxBufSize(EMinBufferSize),

	iDirectAcessCount(0), iInvalidBitmapArray(EFalse)

	{

	}

TInt WsFbsDestroyCallBack(TAny* aBitmapHandle)

	{

	TInt* bitmapHandle=static_cast<TInt*>(aBitmapHandle);

	RWsBuffer::FlushAllBuffers(aBitmapHandle ? *bitmapHandle : 0);

	return(0);

	}

void RWsBuffer::SetCallBack()

	{

	for(RWsBuffer *buffer=(RWsBuffer *)Dll::Tls();buffer;buffer=buffer->iNext)

		if (buffer==this)

			return;	// Already linked

	iNext=(RWsBuffer *)Dll::Tls();

	Dll::SetTls(this);

	if (iNext==NULL)	// First connection so set callback

		RFbsSession::GetSession()->SetCallBack(TCallBack(WsFbsDestroyCallBack,NULL));

	}

void RWsBuffer::CancelCallBack()

	{

	RWsBuffer *buffer=(RWsBuffer *)Dll::Tls();

	if (buffer==this)

		{

		Dll::SetTls(iNext);

		if (iNext==NULL)

			RFbsSession::GetSession()->ResetCallBack();	// Last connection closing so cancel the callback

		}

	else

		{

		RWsBuffer *prev;

		while(buffer)

			{

			prev=buffer;

			buffer=buffer->iNext;

			if (buffer==this)

				{

				prev->iNext=iNext;

				break;

				}

			}

		}

	}

void RWsBuffer::Close()

	{

	User::Free((TAny *)iBuf.Ptr());

	}

void RWsBuffer::Destroy()

	{

	Flush();

	Close();

	delete this;

	}

TInt RWsBuffer::Flush(const TIpcArgs* aIpcArgs,TBool aRequestFinish)

	{

	iBitmapArray.Reset();

	iInvalidBitmapArray=EFalse;

	if (iBuf.Length()==0)

		{

		return(KErrNone);

		}

	TIpcArgs ipcArgs;

	if (aIpcArgs!=NULL)

		{

		ipcArgs=*aIpcArgs;

		// check that the caller hasn't used the first slot

		ipcArgs.Set(KBufferMessageSlot,TIpcArgs::ENothing);

		__ASSERT_ALWAYS(Mem::Compare(REINTERPRET_CAST(const TUint8*, &ipcArgs), sizeof(TIpcArgs), REINTERPRET_CAST(const TUint8*, aIpcArgs), sizeof(TIpcArgs))==0,Panic(EW32PanicUsingReservedIpcSlot));

		}

	ipcArgs.Set(KBufferMessageSlot,&iBuf);

	TInt ret;

	if(aRequestFinish)

		ret=iSession->DoFlush(ipcArgs);

	else

		ret=iSession->DoSyncMsgBuf(ipcArgs);

	iBuf.Zero();

	iPreviousHandle=0;

	return(ret);

	}

void RWsBuffer::FlushAllBuffers(TInt aBitmapHandle)

	{

	for(RWsBuffer *buffer=(RWsBuffer *)Dll::Tls();buffer;buffer=buffer->iNext)

		{

		if(!aBitmapHandle || buffer->iInvalidBitmapArray || (buffer->iBitmapArray.FindInOrder(aBitmapHandle)!=KErrNotFound))

			buffer->Flush();

		}

	}

inline void RWsBuffer::SetAndLimitMaxBufSize(TInt aMaxBufSize)

	{ // apply upper & lower limits to input buffer size

	if (aMaxBufSize < EMinBufferSize)

		{

		iMaxBufSize = EMinBufferSize;

		}

	else if	(aMaxBufSize > EMaxBufferSize)

		{

		iMaxBufSize = EMaxBufferSize;

		}

	else

		{

		iMaxBufSize = aMaxBufSize;

		}

	}

void RWsBuffer::SetBufferSizeL(TInt aBufSize)

	{

	SetAndLimitMaxBufSize(aBufSize);

	ReAllocBufferL(iMaxBufSize);

	}

void RWsBuffer::SetMaxBufferSizeL(TInt aMaxBufSize)

	{

	SetAndLimitMaxBufSize(aMaxBufSize);

	if (iMaxBufSize < iBufSize)

		{ // shrink to new maximum

		ReAllocBufferL(iMaxBufSize);

		}

	else

		{

		 // initial allocation should be (at least) a quarter of the requested size

		TInt minSize = Max( (iMaxBufSize + 3) >> 2, EMinBufferSize);

		if (minSize > iBufSize)

			{ // new or enlarged buffer

			ReAllocBufferL(minSize);

			}

		}

	__ASSERT_DEBUG((iBufSize >= EMinBufferSize) && (iBufSize <= iMaxBufSize), Assert(EW32AssertBufferLogic));

	}

// Flush() buffer, try to ReAlloc, Leave if the ReAlloc fails.

void RWsBuffer::ReAllocBufferL(TInt aNewSize)

	{

	if (aNewSize != iBufSize)

		{

		Flush();

		if (!ReAllocBuffer(aNewSize))

			{

			User::LeaveNoMemory();

			}

		}

	}

TBool RWsBuffer::ReAllocBuffer(TInt aNewSize)

	{

	TUint8* ptr = const_cast<TUint8*>(iBuf.Ptr());

	__ASSERT_DEBUG((iBufSize == 0) || (ptr != NULL), Assert(EW32AssertBufferLogic));

	const TInt len = iBuf.Length();

	TUint8* newPtr = static_cast<TUint8*>(User::ReAlloc(ptr, aNewSize));

	if (newPtr != NULL)

		{ // realloc was successful

		iBuf.Set(newPtr, len, aNewSize);

		iBufSize = aNewSize;

		return ETrue;

		}

	return EFalse;

	}

/* Expand the buffer, to allow new drawing command to fit.

 Called either when trying to store additional commands to queue for Wserv, or

 the trying to send a command bigger than the current buffer size.

 Failure to expand the buffer is a minor problem in the first case but a big 

 problem in the second.

 @param aRequiredSpace Size of buffer increase required.

 @param aMsgSize If expanding the buffer fails then needs this value to know whether Flush() is good enough.

 @return ETrue if there is enough space, EFalse if not.

 */

void RWsBuffer::GrowBuffer(TInt aRequiredSpace, TInt aMsgSize)

	{

	__ASSERT_DEBUG(iBufSize < iMaxBufSize, Assert(EW32AssertBufferLogic));

	// maximum size will be big enough?

	__ASSERT_ALWAYS(aMsgSize <= iMaxBufSize, Panic(EW32PanicDataExceedsBufferLength));

	 // double or quad the current size, then limit it

	TInt newSize = Min((iBufSize >= aRequiredSpace) ? iBufSize << 1 : iBufSize << 2, iMaxBufSize);

	if (!ReAllocBuffer(newSize))

		{ // OOM error

		Flush();

		if (aMsgSize > iBufSize)

			{ // message is too big for buffer

			Panic(EW32PanicDataExceedsBufferLength);

			}

		}

	}

TBool RWsBuffer::SetAutoFlush(TBool aState)

	{

	TBool old;

	old=iAutoFlush;

#if defined(__AUTO_FLUSH)

	if (aState)

#else

	iAutoFlush=aState;

	if (iAutoFlush)

#endif

		Flush();

	return(old);

	}

TInt RWsBuffer::DoWrite(TInt aHandle, TUint aOpcode, TBool aFlush, const TIpcArgs* aIpcArgs, const TAny* aData, TInt aLength, const TAny* aData2, TInt aLength2)

	{

	__ASSERT_DEBUG(((TUint32) aOpcode) < 0x8000, Assert(EW32AssertIllegalOpcode));

	__ASSERT_DEBUG((aLength&0x3) == 0, Assert(EW32AssertOddLengthData));

	TInt xtra(0);

	if (aLength2 > 0)

		{

		xtra = 4 - (aLength2&0x3);		// Round data upto a multiple of 4

		if (xtra==4)

			{

			xtra=0;

			}

		}

	const TInt msgSize = aLength + aLength2 + xtra + static_cast<TInt>(sizeof(TWsCmdHeader));

	TInt available = iBuf.MaxLength() - iBuf.Length();

	if (msgSize > available)

		{

		if (iBufSize >= iMaxBufSize)

			{ // buffer is maximum size already

			Flush();

			}

		else

			{ // try to grow buffer

			 if ( (iBuf.Length() + msgSize) > iMaxBufSize)

				{ // growing alone will not make enough extra space

				Flush();

				available = iBufSize;

				}

			const TInt requiredSpace = msgSize - available;

			if (requiredSpace > 0)

				{

				GrowBuffer(requiredSpace, msgSize);

				}

			}

		}

	TWsCmdHeader cmdHeader;

	cmdHeader.iBase.iOpcode = (TInt16)aOpcode;

	cmdHeader.iBase.iCmdLength = (TInt16)(aLength + aLength2 + xtra);

	// For performance reasons we only pass in the handle if it is different

	// from the previous command

	if (aHandle == iPreviousHandle)

		{

		iBuf.Append((TUint8 *)&cmdHeader.iBase,sizeof(cmdHeader.iBase));

		}

	else

		{

		iPreviousHandle = aHandle;

		cmdHeader.iBase.iOpcode|=EWsOpcodeHandle;

		cmdHeader.iDestHandle = aHandle;

		iBuf.Append((TUint8 *)&cmdHeader,sizeof(cmdHeader));

		}

	if (aLength)

		{

		iBuf.Append((TUint8 *)aData, aLength);

		}

	if (aLength2 > 0)

		{

		iBuf.Append((TUint8 *)aData2, aLength2);

		iBuf.AppendFill(0,xtra);

		}

	if (aFlush)

		{

		return Flush(aIpcArgs);

		}

	return KErrNone;

	}

void RWsBuffer::Write(TInt handle,TUint opcode)

	{

	DoWrite(handle, opcode, iAutoFlush, NULL);

	}

void RWsBuffer::Write(TInt handle,TUint opcode,const TAny *pData, TInt length)

	{

	DoWrite(handle, opcode, iAutoFlush, NULL, pData, length);

	}

void RWsBuffer::Write(TInt handle,TUint opcode,const TAny *pData, TInt length,const TAny *pData2, TInt length2)

	{

	DoWrite(handle, opcode, iAutoFlush, NULL, pData, length, pData2, length2);

	}

TInt RWsBuffer::WriteReply(TInt handle,TUint opcode,const TIpcArgs* aIpcArgs)

	{

	return DoWrite(handle, opcode, ETrue, aIpcArgs);

	}

TInt RWsBuffer::WriteReply(TInt handle,TUint opcode,const TAny *pData, TInt length,const TIpcArgs* aIpcArgs)

	{

	return DoWrite(handle, opcode, ETrue, aIpcArgs, pData, length);

	}

TInt RWsBuffer::WriteReply(TInt handle,TUint opcode,const TAny *pData,TInt length,const TAny *pData2,TInt length2,const TIpcArgs* aIpcArgs)

	{

	return DoWrite(handle, opcode, ETrue, aIpcArgs, pData, length, pData2, length2);

	}

TInt RWsBuffer::WriteReplyP(TInt aHandle, TUint aOpcode, const TWriteDescriptorType& aReplyBuffer)

	{

	TIpcArgs ipcArgs;

	aReplyBuffer.SetDescriptorOnIpcArgs(ipcArgs);

	return DoWrite(aHandle, aOpcode, ETrue, &ipcArgs);

	}

TInt RWsBuffer::WriteReplyP(TInt aHandle,TUint aOpcode,const TAny *aData,TInt aLength,const TWriteDescriptorType& aReplyBuffer)

	{

	TIpcArgs ipcArgs;

	aReplyBuffer.SetDescriptorOnIpcArgs(ipcArgs);

	return DoWrite(aHandle, aOpcode, ETrue, &ipcArgs, aData, aLength);

	}

TInt RWsBuffer::WriteReplyP(TInt aHandle,TUint aOpcode,const TAny *aData1,TInt aLengthData1,const TAny *aData2,TInt aLengthData2,const TWriteDescriptorType& aReplyBuffer)

	{

	TIpcArgs ipcArgs;

	aReplyBuffer.SetDescriptorOnIpcArgs(ipcArgs);

	return DoWrite(aHandle, aOpcode, ETrue, &ipcArgs, aData1, aLengthData1, aData2, aLengthData2);

	}

TInt RWsBuffer::WriteReplyWs(TUint opcode)

//

// Do a WriteReply using the sessions handle

//

	{

	return(iSession->WriteReply(opcode));

	}

TInt RWsBuffer::WriteReplyWs(const TAny *pData, TInt aLength, TUint aOpcode)

//

// Do a WriteReply using the sessions handle

//

	{

	return(iSession->WriteReply(pData,aLength,aOpcode));

	}

TInt RWsBuffer::WriteReplyWs(const TAny *pData, TInt aLength, const TAny *pData2, TInt aLength2, TUint aOpcode)

//

// Do a WriteReply using the sessions handle

//

	{

	return(iSession->WriteReply(pData,aLength,pData2,aLength2,aOpcode));

	}

TInt RWsBuffer::WriteReplyByProvidingRemoteReadAccess(TInt aHandle,TUint aOpcode,const TAny *aData, TInt aLength,const TReadDescriptorType& aRemoteReadBuffer)

	{

	TIpcArgs ipcArgs;

	aRemoteReadBuffer.SetDescriptorOnIpcArgs(ipcArgs);

	return DoWrite(aHandle, aOpcode, ETrue, &ipcArgs, aData, aLength);

	}

void RWsBuffer::AddToBitmapArray(TInt aBitmapHandle)

	{

	if(aBitmapHandle && !iInvalidBitmapArray)

		{

		if(iBitmapArray.InsertInOrder(aBitmapHandle)==KErrNoMemory)

			iInvalidBitmapArray=ETrue;

		}

	}

void RWsBuffer::SetWsGraphicManager(CWsGraphic::CManager* aManager)

	{

	__ASSERT_DEBUG(!WsGraphicManager(),Panic(EW32PanicGraphicInternal));

	iManager = aManager;

	}

CWsGraphic::CManager* RWsBuffer::WsGraphicManager()

	{

	for(RWsBuffer *buffer=(RWsBuffer *)Dll::Tls();buffer;buffer=buffer->iNext)

		if (buffer->iManager)

			return buffer->iManager;	

	return NULL; // does not yet exist

	}