examples/SFExamples/symbian_os_communications_programming_book_v2/chapter8/receivingmessages/CWeatherReportWatcher.cpp

// 
// Copyright (c) 2002-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the License "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:
// 

#include "CWeatherReportWatcher.h"

#include <smsuaddr.h>
#include <GSMUBUF.H>
#include <GSMUMSG.H>
#include <SMSUSTRM.H>

_LIT8(KWeatherReportPrefixString, "Weather:");
const TInt KMaxWeatherReportLength = 9;

CWeatherReportWatcher::~CWeatherReportWatcher()
        {
        iSmsSocket.Close();
        iSocketServer.Close();
        }

CWeatherReportWatcher* CWeatherReportWatcher::NewL(MWeatherReportObserver& aWeatherReportObserver, RFs& aFs)
        {
        CWeatherReportWatcher* self = new (ELeave) CWeatherReportWatcher(aWeatherReportObserver, aFs);
        CleanupStack::PushL(self);
        self->ConstructL();
        CleanupStack::Pop(self);
        return self;
        }

// CActive functions
void CWeatherReportWatcher::DoCancel()
        {
        // Any outstanding operation would usually be cancelled here.
        // However, it will never be called in this code.
        }

void CWeatherReportWatcher::RunL()
        {
        if (iState == EWaitingForWeatherReport)
                {
                CSmsBuffer* smsBuffer=CSmsBuffer::NewL();
                CleanupStack::PushL(smsBuffer);
                
                CSmsMessage* smsMessage = CSmsMessage::NewL(iFs, CSmsPDU::ESmsDeliver, smsBuffer);
                
                // smsMessage has taken ownership of smsBuffer so remove it from the cleanup stack.
                CleanupStack::Pop(smsBuffer);
                
                CleanupStack::PushL(smsMessage);

                RSmsSocketReadStream readstream(iSmsSocket);
                
                // This function may leave
                readstream >> *smsMessage;

                // Extract the text from the SMS buffer
                TBuf<KMaxWeatherReportLength> weatherReportBuf;
                TInt bufferLength = smsBuffer->Length();        
                if (bufferLength > KMaxWeatherReportLength)
                        bufferLength = KMaxWeatherReportLength;
                smsBuffer->Extract(weatherReportBuf, 0, bufferLength);

                MWeatherReportObserver::TWeatherReport weatherReport = MWeatherReportObserver::ENone;

                // Process the message
                if (weatherReportBuf.Length() >= KMaxWeatherReportLength)
                        {
                        // Get the last character. The last character represents the weather report.
                        TUint16 lastCharacter = weatherReportBuf[KMaxWeatherReportLength - 1];
                
                        // Process the message
                        switch (lastCharacter)
                                {
                        case '1':
                                weatherReport = MWeatherReportObserver::ESunny;
                                break;
                        case '2':
                                weatherReport = MWeatherReportObserver::ECloudy;
                                break;
                        case '3':
                                weatherReport = MWeatherReportObserver::ERainy;
                                break;
                        
                                // No deafault. Leave weather report as 'None'.
                                }
                        }
                        
                // Update the UI with the new weather report
                iWeatherReportObserver.NewWeatherReport(weatherReport);

                CleanupStack::PopAndDestroy(smsMessage);
                
                // Acknowledge receipt of the SMS message, otherwise it will be resent
                TPckgBuf<TUint> sbuf;
                iStatus = KRequestPending;
                iSmsSocket.Ioctl(KIoctlReadMessageSucceeded, iStatus, &sbuf, KSolSmsProv);
                
                // Wait for the acknowledgement to be sent, go active.
                iState = EAcknowledgingWeatherReport;
                SetActive();
                }
        else if (iState == EAcknowledgingWeatherReport)
                {
                // The acknowledgement has now been sent so wait for another weather report.
                WaitForWeatherReportL();
                }
        }
        
CWeatherReportWatcher::CWeatherReportWatcher(MWeatherReportObserver& aWeatherReportObserver, RFs& aFs) : CActive(EPriorityStandard), iWeatherReportObserver(aWeatherReportObserver), iFs(aFs)
        {
        }

void CWeatherReportWatcher::ConstructL()
        {
        CActiveScheduler::Add(this);

        // Connect to sockets server
        // SMS messages are intercepted via sockets
        User::LeaveIfError(iSocketServer.Connect());
        
        // Open SMS socket
        User::LeaveIfError(iSmsSocket.Open(iSocketServer,KSMSAddrFamily,KSockDatagram,KSMSDatagramProtocol));
        
        // Set SMS prefix - only intercept SMS messages starting with a particular string
        TSmsAddr smsAddress;
        smsAddress.SetSmsAddrFamily(ESmsAddrMatchText);
        smsAddress.SetTextMatch(KWeatherReportPrefixString);
        iSmsSocket.Bind(smsAddress);
        
        WaitForWeatherReportL();
        }

void CWeatherReportWatcher::WaitForWeatherReportL()
        {
        
        // Wait for an appropriate SMS message
        // the RunL will be called when an appropriate SMS message is received
        
        // Note that the smsAddress has already been set in ConstructL so we will only
        // intercept messages starting with 'Weather:'
        
        iSbuf()=KSockSelectRead;
        iStatus = KRequestPending;
        iSmsSocket.Ioctl(KIOctlSelect, iStatus, &iSbuf, KSOLSocket);
        iState = EWaitingForWeatherReport;
        
        SetActive();
        }

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