examples/Base/MessageQueueExample/src/CCollector.cpp

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/*
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DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Description: 
The following class takes user input and sends it to a different 
process called inverter.exe via InverterInQ message Queue. 
*/




#include "CCollector.h"
_LIT(KTitle,"InputMessage");
_LIT(KWelcome," Welcome to Message Queue Example application for the global queues\n");
_LIT(KEnterWords, "\n Enter some words and press enter key to send to inverter or Press Esc to exit.\n");
_LIT(KGlobalInverterInQ, "InverterInQ");
_LIT(KGlobalInverterOutQ, "InverterOutQ");
const TInt KNumberOfMsgs = 10;

CCollector::CCollector(TInt aPriority):CActive( aPriority )
        {       
        CActiveScheduler::Add(this);
        }

CCollector::~CCollector()
        {
        Cancel();
        }

void CCollector::DoCancel()
        {
        }

void CCollector::ConstructL()
        {
        iConsole = Console::NewL(KTitle, TSize(KConsFullScreen, KConsFullScreen));
        iConsole->Printf(KWelcome);
        iConsole->Printf(KEnterWords);
        
        //Create global message queue , which is used as input to the inverter and output to the collector.
        User::LeaveIfError(iInverterInQ.CreateGlobal(KGlobalInverterInQ, KNumberOfMsgs, EOwnerProcess));
                
        //Create global message queue , which is used as output to the inverter and input to the collector.
        User::LeaveIfError(iInverterOutQ.CreateGlobal(KGlobalInverterOutQ, KNumberOfMsgs, EOwnerProcess));
        
        //Start Inverter process.
        _LIT(KProcessName, "inverter.exe");
        User::LeaveIfError(process.Create(KProcessName, KNullDesC));
        process.Resume();
        
        iRcvInverterInQ= CMsgQActive::NewL(); 
        }

CCollector* CCollector::NewL(TInt aPriority)
        {
        CCollector* self=new(ELeave)CCollector(aPriority);
        CleanupStack::PushL(self);
        self->ConstructL();
        CleanupStack::Pop(self);
        return self;
        }

void CCollector::RequestFunction()
        {
        iConsole->Read(iStatus);
        SetActive();
        }

void CCollector::RunL()
        {
        //Store the words input by the user in a buffer.
        _LIT(KChar,"%c");
        iConsole->Printf(KChar,(TUint8)(iConsole->KeyCode()));
        iBuf.Append(iConsole->KeyCode());       
        ProcessKeyPress(TChar(iConsole->KeyCode()));
        }

void CCollector::ProcessKeyPress(TChar aChar)
    {    
    if (aChar == EKeyEscape)
        {
        this->Stop();
        }
    else if(aChar == EKeyEnter)
        {
        _LIT(KNextLine , "\n");
        iConsole->Printf(KNextLine);
        this->SendMsgInQ(iBuf); 
        iBuf.Zero();
        this->RequestFunction();        
        }
    else
        {
        this->RequestFunction();  
        }       
    }

void CCollector::Stop()
        {
    TBuf<1> escape;
    escape.Append(EKeyEscape); 
    //Sends stop message to the inverter.
    this->SendMsgInQ(escape); 
    
    //Cancel any outstanding request.
    iRcvInverterInQ->Cancel();
    delete iRcvInverterInQ;
    delete iConsole;
    CActiveScheduler::Stop();   
    escape.Zero();
        }

void CCollector::StartRecieving()
        {
        iRcvInverterInQ->StartRecieving();
        }

void CCollector::SendMsgInQ(TBuf<100> buf)
        {
        TInt ret = iInverterInQ.OpenGlobal(KGlobalInverterInQ); 
        if (ret == KErrNone)
        {
        iInverterInQ.SendBlocking(buf);
        }
        }

LOCAL_C void DoStartL()
        {
        // Create active scheduler (to run active objects)
        CActiveScheduler* scheduler = new (ELeave) CActiveScheduler();
        CleanupStack::PushL(scheduler);
        CActiveScheduler::Install(scheduler);

        CCollector* iCollect= CCollector::NewL();
        CleanupStack::PushL(iCollect);
        
         //Start getting the user input.
        iCollect->RequestFunction();
        
        //Recieve data from the inverter in another console.
        iCollect->StartRecieving();
        CActiveScheduler::Start();
        
        CleanupStack::PopAndDestroy(iCollect);
        CleanupStack::PopAndDestroy(scheduler); 
        }

GLDEF_C TInt E32Main()
        {
        __UHEAP_MARK;
        CTrapCleanup* cleanup = CTrapCleanup::New();
        if(cleanup == NULL)
                {
                return KErrNoMemory;
                }
        TRAPD(mainError, DoStartL());
        if(mainError != KErrNone)
                {
                _LIT(KUserPanic,"Failed to complete");  
                User::Panic(KUserPanic, mainError);
                }
                delete cleanup;
                __UHEAP_MARKEND;
                return KErrNone;
        }

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