cmmanager/cmmgr/cmmserver/src/cmmtransactionhandler.cpp
changeset 20 9c97ad6591ae
child 40 c5b848e6c7d1
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cmmanager/cmmgr/cmmserver/src/cmmtransactionhandler.cpp	Mon May 03 12:53:07 2010 +0300
@@ -0,0 +1,201 @@
+/*
+* Copyright (c) 2009-2010 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:
+* Common transaction handler of framework and plugins.
+*
+*/
+
+
+#include "cmmtransactionhandler.h"
+
+#include "OstTraceDefinitions.h"
+#ifdef OST_TRACE_COMPILER_IN_USE
+#include "cmmtransactionhandlerTraces.h"
+#endif
+
+const TUint32 KMaxOpenTransAttempts = 10;
+const TUint32 KRetryAfter = 100000;
+
+
+// ---------------------------------------------------------------------------
+// NewL.
+// ---------------------------------------------------------------------------
+//
+CCmmTransactionHandler* CCmmTransactionHandler::NewL( CommsDat::CMDBSession& aDb )
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_NEWL_ENTRY );
+
+    CCmmTransactionHandler* self = new( ELeave ) CCmmTransactionHandler( aDb );
+    CleanupStack::PushL( self );
+    self->ConstructL();
+    CleanupStack::Pop( self );
+
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_NEWL_EXIT );
+    return self;
+    }
+
+// ---------------------------------------------------------------------------
+// Destructor.
+// ---------------------------------------------------------------------------
+//
+CCmmTransactionHandler::~CCmmTransactionHandler()
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_CCMTRANSACTIONHANDLER_ENTRY );
+    delete &iDb;
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_CCMTRANSACTIONHANDLER_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Constructor.
+// ---------------------------------------------------------------------------
+//
+CCmmTransactionHandler::CCmmTransactionHandler( CommsDat::CMDBSession& aDb ) : iDb( aDb )
+    {
+    OstTraceFunctionEntry0( DUP1_CCMTRANSACTIONHANDLER_CCMTRANSACTIONHANDLER_ENTRY );
+    iRefCount = 0;
+    OstTraceFunctionExit0( DUP1_CCMTRANSACTIONHANDLER_CCMTRANSACTIONHANDLER_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Second phase constructor.
+// ---------------------------------------------------------------------------
+//
+void CCmmTransactionHandler::ConstructL()
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_CONSTRUCTL_ENTRY );
+    iDb.SetAttributeMask( CommsDat::ECDHidden | CommsDat::ECDProtectedWrite );
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_CONSTRUCTL_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Return the CommsDat session.
+// ---------------------------------------------------------------------------
+//
+CommsDat::CMDBSession& CCmmTransactionHandler::Session() const
+    {
+    return iDb;
+    }
+
+// ---------------------------------------------------------------------------
+// Opens a CommsDat transaction if it is not already open. Reference counter
+// is inreased by one.
+// ---------------------------------------------------------------------------
+//
+void CCmmTransactionHandler::OpenTransactionLC()
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_OPENTRANSACTIONLC_ENTRY );
+
+    iRefCount++;
+    CleanupClosePushL( *this );
+
+    if ( !iDb.IsInTransaction() )
+        {
+        TInt err( KErrNone );
+        TUint32 attempts( KMaxOpenTransAttempts );
+
+        do
+            {
+            TRAP( err, iDb.OpenTransactionL() );
+            if ( err )
+                {
+                User::After( KRetryAfter );
+                }
+            } while ( err && attempts-- );
+        User::LeaveIfError( err );
+        }
+
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_OPENTRANSACTIONLC_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Decreases the reference counter by one. If it reaches zero, commits the open
+// CommsDat transaction. If an error code is given as argument, the CommsDat
+// transaction is rolled back instead.
+// ---------------------------------------------------------------------------
+//
+void CCmmTransactionHandler::CommitTransactionL( TInt aError )
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_COMMITTRANSACTIONL_ENTRY );
+
+    iRefCount--;
+    CleanupStack::Pop( this );
+
+    if ( !iRefCount )
+        {
+        if ( aError )
+            {
+            iDb.RollbackTransactionL();
+            }
+        else
+            {
+            iDb.CommitTransactionL();
+            }
+        }
+
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_COMMITTRANSACTIONL_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Performs RollbackTransactionL().
+// Pay attention to CleanupStack if calling this. The transaction handler
+// needs to be popped from CleanupStack manually.
+// ---------------------------------------------------------------------------
+//
+void CCmmTransactionHandler::Close()
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_CLOSE_ENTRY );
+
+    if ( iRefCount == 0 )
+        {
+        // No active transaction, do nothing.
+        OstTraceFunctionExit0( DUP1_CCMTRANSACTIONHANDLER_CLOSE_EXIT );
+        return;
+        }
+
+    if ( !iDb.IsInTransaction() )
+        {
+        // Sometimes CommsDat closes the transaction on its own decision w/o any
+        // notification or reason. E.g. when you try to delete a non-existing
+        // record, it leaves with KErrNotFound, but rolls back the transaction.
+        iRefCount = 0;
+        }
+    else
+        {
+        iRefCount--;
+
+        if ( !iRefCount )
+            {
+            if ( iDb.IsInTransaction() )
+                {
+                TRAP_IGNORE( iDb.RollbackTransactionL() );
+                }
+            }
+        }
+
+    OstTraceFunctionExit0( DUP2_CCMTRANSACTIONHANDLER_CLOSE_EXIT );
+    }
+
+// ---------------------------------------------------------------------------
+// Return the current reference count. Transaction is currently open if the
+// count above 0.
+// ---------------------------------------------------------------------------
+//
+TUint32 CCmmTransactionHandler::GetReferenceCount()
+    {
+    OstTraceFunctionEntry0( CCMTRANSACTIONHANDLER_GETREFERENCECOUNT_ENTRY );
+    OstTraceFunctionExit0( CCMTRANSACTIONHANDLER_GETREFERENCECOUNT_EXIT );
+    return iRefCount;
+    }
+
+// End of file