--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/sdkcreationmw/sdkruntimes/MIDP/DebugAgent/src/JavaDebugAgentKeepAlive.cpp	Mon Mar 08 12:09:11 2010 +0530
@@ -0,0 +1,232 @@
+/*
+* Copyright (c) 2006 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: 
+*
+*/
+
+
+#include <in_sock.h>
+#include <ip4_hdr.h>
+#include "JavaDebugAgentKeepAlive.h"
+
+// CJavaDebugAgentKeepAlive::CReceiver
+class CJavaDebugAgentKeepAlive::CReceiver : public CActive
+{
+private:
+    RSocket* iSocket;
+    TSockXfrLength iLength;
+    TBuf8<1> iBuf;
+public:
+    CReceiver(RSocket* aSocket);
+    void Recv();
+    virtual void RunL();
+    virtual void DoCancel();
+};
+
+CJavaDebugAgentKeepAlive::CReceiver::CReceiver(RSocket* aSocket) :
+CActive(EPriorityStandard),
+iSocket(aSocket)
+{ 
+    CActiveScheduler::Add(this);
+}
+
+void CJavaDebugAgentKeepAlive::CReceiver::RunL()
+{
+    if (iStatus.Int() == KErrNone) Recv();
+}
+
+void CJavaDebugAgentKeepAlive::CReceiver::DoCancel()
+{
+    iSocket->CancelRead();
+}
+
+void CJavaDebugAgentKeepAlive::CReceiver::Recv()
+{
+    SetActive();
+    iStatus = KRequestPending;
+    iSocket->RecvOneOrMore(iBuf, 0, iStatus, iLength);
+}
+
+// CJavaDebugAgentKeepAlive
+CJavaDebugAgentKeepAlive* 
+CJavaDebugAgentKeepAlive::NewL(RSocketServ* aSocketServ, 
+                               const TSockAddr* aAddr,
+                               MJavaDebugAgentLog* aLog,
+                               TInt aPeriod)
+{
+    CJavaDebugAgentKeepAlive* self = NewLC(aSocketServ, aAddr, aLog, aPeriod);
+    CleanupStack::Pop(self);
+    return self;
+}
+
+CJavaDebugAgentKeepAlive* 
+CJavaDebugAgentKeepAlive::NewLC(RSocketServ* aSocketServ, 
+                                const TSockAddr* aAddr,
+                                MJavaDebugAgentLog* aLog,
+                               TInt aPeriod)
+{
+    CJavaDebugAgentKeepAlive* self = new(ELeave)
+        CJavaDebugAgentKeepAlive(aSocketServ, aAddr, aLog, aPeriod);
+    CleanupStack::PushL(self);
+    self->ConstructL();
+    return self;
+}
+
+CJavaDebugAgentKeepAlive::~CJavaDebugAgentKeepAlive()
+{
+    Cancel();
+    delete iReceiver;
+    iSocket.Close();
+    iTimer.Close();
+}
+
+CJavaDebugAgentKeepAlive::
+CJavaDebugAgentKeepAlive(RSocketServ* aSocketServ,
+                         const TSockAddr* aAddr,
+                         MJavaDebugAgentLog* aLog,
+                         TInt aPeriodInMilliseconds) :
+CActive(EPriorityStandard),
+iPeriod(aPeriodInMilliseconds*1000),
+iSocketServ(aSocketServ),
+iAddress(*aAddr),
+iLog(aLog)
+{
+    CActiveScheduler::Add(this);
+    iMsg.FillZ(iMsg.MaxLength());
+    iMsg[0] = KInet4ICMP_Echo;
+    iMsg[8] = 'P';
+    iMsg[9] = 'I';
+    iMsg[10] = 'N';
+    iMsg[11] = 'G';
+}
+
+void CJavaDebugAgentKeepAlive::ConstructL()
+{
+    iReceiver = new(ELeave)CReceiver(&iSocket);
+    User::LeaveIfError(iTimer.CreateLocal());
+    User::LeaveIfError(iSocket.Open(*iSocketServ, KAfInet, 
+        KSockDatagram, KProtocolInetIcmp));
+
+    SetActive();
+    iStatus = KRequestPending;
+    iState = EConnecting;
+    iSocket.Connect(iAddress, iStatus);
+}
+
+// CActive
+void CJavaDebugAgentKeepAlive::RunL()
+{
+    TInt err = iStatus.Int();
+    switch (iState)
+    {
+    case EConnecting:
+        if (err == KErrNone)
+        {
+            iReceiver->Recv();
+            Ping();
+        }
+        else
+        {
+            iState = EFailed;
+            iLog->LogFormat(_S("KeepAlive connect error %d"),err);
+        }
+        break;
+
+    case ESending:
+        if (err == KErrNone)
+        {
+            Wait();
+        }
+        else
+        {
+            iState = EFailed;
+            iLog->LogFormat(_S("KeepAlive send error %d"),err);
+        }
+        break;
+
+    case EWaiting:
+        if (err == KErrNone)
+        {
+            Ping();
+        }
+        else
+        {
+            iState = EFailed;
+            iLog->LogFormat(_S("KeepAlive wait error %d"),err);
+        }
+        break;
+    }
+}
+
+void CJavaDebugAgentKeepAlive::Wait()
+{
+    SetActive();
+    iStatus = KRequestPending;
+    iState = EWaiting;
+    iTimer.After(iStatus,iPeriod);
+}
+
+void CJavaDebugAgentKeepAlive::Ping()
+{
+    TUint16* ptr16 = ((TUint16*)&iMsg[0]);
+    ptr16[1] = 0;  // checksum
+    iSeq++;
+    iMsg[6] = (TUint8)(iSeq >> 8); // convert to network byte order
+    iMsg[7] = (TUint8)iSeq;
+
+    // Checksum is calculated in native byte order, and stored natively too
+    TUint16 sum = 0;
+    for (TInt i=iMsg.Length()/2-1; i>=0; i--) sum += ptr16[i];
+    ptr16[1] = ~sum;
+
+    // Send the message
+    SetActive();
+    iStatus = KRequestPending;
+    iState = ESending;
+    iSocket.SendTo(iMsg, iAddress, 0, iStatus);
+}
+
+TInt CJavaDebugAgentKeepAlive::RunError(TInt /*aError*/)
+{
+    iState = EFailed;
+    return KErrNone;
+}
+
+void CJavaDebugAgentKeepAlive::DoCancel()
+{
+    TRequestStatus *status;
+    switch (iState)
+    {
+    case EConnecting:
+        iSocket.CancelConnect();
+        break;
+    case ESending:
+        iSocket.CancelSend();
+        break;
+    case EWaiting:
+        iTimer.Cancel();
+        break;
+    default:
+		status = (&iStatus);
+		User::RequestComplete(status, KErrCancel);
+        break;
+    }
+}
+
+/**
+ * Local Variables:
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */