examples/Base/IPC/AdvancedClientServerExample/ProcessServer/src/processserver.cpp

/*
Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this
  list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.
* Neither the name of Nokia Corporation nor the names of its contributors
  may be used to endorse or promote products derived from this software
  without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Description:  
*/


#include "processserver.h"
#include "processserverstart.h"
#include "processserversession.h"
#include<e32debug.h>

const TInt KProcessServerShutDownDelay = 50000000; //50 sec

//******CProcessServer******//
void CProcessServer::NewLC()
        {
        CProcessServer* s = new(ELeave) CProcessServer();
        CleanupStack::PushL(s);
        s->ConstructL();
        }
CProcessServer::CProcessServer()
        :CServer2(EPriorityStandard, ESharableSessions),iDriverState(EStateUnknown)
        {
        }
void CProcessServer::ConstructL()
        {
        // Call CServer2::StartL() before any other functions inside ConstructL()
        // to avoid an error other than KErrAlreadyExists when the duplicate server starts
        StartL(KProcessServerName);
        iDelayProcessServerShutDown = CDelayServerShutDown::NewL();
        }
CProcessServer::~CProcessServer()
        {
        if (iDelayProcessServerShutDown)
                {
                iDelayProcessServerShutDown->Cancel();
                delete iDelayProcessServerShutDown;
                }
                
        // unload device driver when server terminated
        UnloadDevice();
        }
CSession2* CProcessServer::NewSessionL(const TVersion& aVersion,const RMessage2& aMessage) const
        {
        //check whether version is compatible
        TVersion v(KProcessServerVersion,KProcessServerMinorVersionNumber,KProcessServerBuildVersionNumber);
        if(!User::QueryVersionSupported(v, aVersion))
                User::Leave(KErrNotSupported);
        
        // check client process has the required capability
        if(!aMessage.HasCapability(ECapabilityMultimediaDD))
                User::Leave(KErrPermissionDenied);              

        // construct and return the server side client session object
        CProcessServer& ncThis = const_cast<CProcessServer&>(*this);
        CProcessServerSession* serverSession = CProcessServerSession::NewL(ncThis);
        return serverSession;
        }
void CProcessServer::IncrementRefCount()
        {
        iRefCount++;
        iDelayProcessServerShutDown->Cancel(); // Cancel shutdown if it has started due to no clients being connected 
        }
        
void CProcessServer::DecrementRefCount() 
        {
        iRefCount--;
        if ( iRefCount == 0 )
                {
                iDelayProcessServerShutDown->SetDelay(TTimeIntervalMicroSeconds32(KProcessServerShutDownDelay));
                }
        }
TInt CProcessServer::LoadDevice()
        {
        if (iDriverState>=EDriverLoaded && iDriverState<EDriverUnloaded)
                return KErrNone; //Device has been loaded, return immediately
                
        TInt r=User::LoadPhysicalDevice(KDriver1PddFileName);
        if (r!=KErrNone && r!=KErrAlreadyExists)
                {
                return r; //some error occurred
                }

        r = User::LoadLogicalDevice(KDriver1LddFileName);
        if (r!=KErrNone && r!=KErrAlreadyExists)
                {
                return r; //some error occurred 
                }

        //both PDD and LDD have been loaded
        UpdateDriverState(EDriverLoaded);
        return KErrNone; 
        }
TInt CProcessServer::UnloadDevice()
        {
        if (iDriverState==EDriverUnloaded || iDriverState == EStateUnknown)
                return KErrNone; //no device is loaded, return immediately
                
        // close device
        if (iDriver.Handle())
                iDriver.Close();
        // Unload Logical Device
        TInt r = User::FreeLogicalDevice(RDriver1::Name());
        if (r!=KErrNone)
                return r;
        // Unload Physical Device
        TName pddName(RDriver1::Name());
        _LIT(KVariantExtension,".template");
        pddName.Append(KVariantExtension);
        r=User::FreePhysicalDevice(pddName);
        
        if (KErrNone==r)
                UpdateDriverState(EDriverUnloaded);     
        return r;
        }
TInt CProcessServer::OpenLogicalChannel()
        {
        if (iDriverState>=ELogicalChannelOpened && iDriverState<ELogicalChannelClosed)
                return KErrNone;
        
        TInt r = iDriver.Open();
        if (KErrNone==r)
                UpdateDriverState(ELogicalChannelOpened);
        
        return r;
        }
void CProcessServer::CloseLogicalChannel()
        {
        if (iDriver.Handle())
                {
                iDriver.Close();
                UpdateDriverState(ELogicalChannelClosed);
                }
        }
TInt CProcessServer::SendDataToDevice(TRequestStatus& aStatus, const TDesC8& aData)
        {
        TInt r = KErrNone;
        if (iDriverState>=ELogicalChannelOpened && iDriverState<ELogicalChannelClosed)
                {
                iDriver.SendData(aStatus, aData);
                UpdateDriverState(ESendingData);
                }
        else
                {
                r = KErrArgument;
                }
        return r;
        }
void CProcessServer::CancelSendData()
        {
        iDriver.SendDataCancel();
        UpdateDriverState(ELogicalChannelOpened);
        }
void CProcessServer::UpdateDriverState(TDriverState aState)
        {
        iDriverState = aState;
        }

//EOF

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