sl@0: // Copyright (c) 1998-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: // All rights reserved.
sl@0: // This component and the accompanying materials are made available
sl@0: // under the terms of "Eclipse Public License v1.0"
sl@0: // which accompanies this distribution, and is available
sl@0: // at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: //
sl@0: // Initial Contributors:
sl@0: // Nokia Corporation - initial contribution.
sl@0: //
sl@0: // Contributors:
sl@0: //
sl@0: // Description:
sl@0: // DBMS server: data source management and sharing classes
sl@0: // 
sl@0: //
sl@0: 
sl@0: #include "SD_STD.H"
sl@0: 
sl@0: extern const TDbDriver KBuiltinDriver;
sl@0: 
sl@0: // Class CDbsObserver::HObserver
sl@0: 
sl@0: // The server side of a RDbNotifier object
sl@0: // All "observers" on the same database are held in a list on the
sl@0: // primary CDbsObserver, which tracks the single notifier object
sl@0: // on the data source.
sl@0: 
sl@0: inline CDbsObserver::HObserver::HObserver()
sl@0: 	:iPending(0)
sl@0: 	{}
sl@0: 
sl@0: //
sl@0: // Complete the outstanding request, and reset the observer status
sl@0: //
sl@0: void CDbsObserver::HObserver::Complete(TInt aStatus)
sl@0: 	{
sl@0: 	iPending=0;
sl@0: 	iMessage.Complete(aStatus);
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Notification request from the client
sl@0: // Int0() has the notification type (CDbNotifier::TType)
sl@0: //
sl@0: void CDbsObserver::HObserver::Notify(const RMessage2& aMessage)
sl@0: 	{
sl@0: 	__ASSERT_ALWAYS(iPending>=0,Panic(EDbsObserverRequestPending));
sl@0: 	iMessage=aMessage;
sl@0: 	if (iPending>RDbNotifier::EUnlock)
sl@0: 		Complete(iPending);				// report any missed event first
sl@0: 	else if (iLink.iNext==&iLink)
sl@0: 		Complete(RDbNotifier::EClose);	// report a "closed" event
sl@0: 	else
sl@0: 		iPending=aMessage.Int0();		// wait for an event
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Cancel the notification request (if pending)
sl@0: //
sl@0: void CDbsObserver::HObserver::Cancel()
sl@0: 	{
sl@0: 	if (iPending<0)
sl@0: 		Complete(KErrCancel);
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // An event occurs on the database
sl@0: //
sl@0: void CDbsObserver::HObserver::Event(TInt aEvent)
sl@0: 	{
sl@0: 	if (aEvent==RDbNotifier::EClose)
sl@0: 		{	// detach the observer when closed
sl@0: 		iLink.Deque();
sl@0: 		iLink.iPrev=iLink.iNext=&iLink;
sl@0: 		}
sl@0: 	TInt pending=iPending;
sl@0: 	if (pending<0)
sl@0: 		{	// request is pending
sl@0: 		if (aEvent==RDbNotifier::EUnlock && pending==CDbNotifier::EChange)
sl@0: 			;	// don't report unlock events to "change" requests
sl@0: 		else
sl@0: 			Complete(aEvent);
sl@0: 		}
sl@0: 	else if (aEvent>pending)
sl@0: 		iPending=aEvent;	// store more significant event
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Client notifer is closed
sl@0: //
sl@0: CDbsObserver::HObserver::~HObserver()
sl@0: 	{
sl@0: 	Cancel();
sl@0: 	iLink.Deque();
sl@0: 	}
sl@0: 
sl@0: // Class CDbsObserver
sl@0: 
sl@0: // The central server-side observer active object for the database notifiers
sl@0: // This maintains a list of all notifiers, and propogates events from the
sl@0: // database source.
sl@0: 
sl@0: inline CDbsObserver::CDbsObserver(CDbsSource& aSource)
sl@0: 	:CActive(10),iSource(aSource),iQueue(_FOFF(HObserver,iLink))
sl@0: 	{}
sl@0: 
sl@0: CDbsObserver* CDbsObserver::NewL(CDbsSource& aSource)
sl@0: 	{
sl@0: 	CDbsObserver* self=new(ELeave) CDbsObserver(aSource);
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->iNotifier=aSource.Source().NotifierL();
sl@0: 	CActiveScheduler::Add(self);
sl@0: 	CleanupStack::Pop();	// self
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Used by the source to destroy the observer only when all client
sl@0: // notifiers have been closed
sl@0: //
sl@0: CDbsObserver* CDbsObserver::Collect(CDbsObserver* aObserver)
sl@0: 	{
sl@0: 	if (!aObserver)
sl@0: 		return aObserver;
sl@0: 	if (!aObserver->iQueue.IsEmpty())
sl@0: 		return aObserver;
sl@0: 	delete aObserver;
sl@0: 	return 0;
sl@0: 	}
sl@0: 
sl@0: CDbsObserver::~CDbsObserver()
sl@0: 	{
sl@0: 	__ASSERT(iQueue.IsEmpty());
sl@0: 	CDbObject::Destroy(iNotifier);	// will cancel any request
sl@0: 	Cancel();
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Create and initialise a new client-observer object
sl@0: //
sl@0: CDbsObserver::HObserver* CDbsObserver::ObserverL()
sl@0: 	{
sl@0: 	HObserver* observer=new(ELeave) HObserver;
sl@0: 	iQueue.AddLast(*observer);
sl@0: 	if (!IsActive())
sl@0: 		Queue();		// start receiving events
sl@0: 	return observer;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Request an event from the database
sl@0: //
sl@0: void CDbsObserver::Queue()
sl@0: 	{
sl@0: 	SetActive();
sl@0: 	iNotifier->Notify(CDbNotifier::EUnlock,iStatus);
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Dispatch the event to all observers and re-queue
sl@0: //
sl@0: void CDbsObserver::RunL()
sl@0: 	{
sl@0: 	TDblQueIter<HObserver> iter(iQueue);
sl@0: 	for (HObserver* ob;(ob=iter++)!=0;)
sl@0: 		ob->Event(iStatus.Int());
sl@0: 	if (!iQueue.IsEmpty())
sl@0: 		Queue();
sl@0: 	else if (iStatus.Int()==RDbNotifier::EClose)
sl@0: 		iSource.Closed();	// disconnect and destroy on a close event
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Provided fo CActive: should never have to do anything as called only
sl@0: // via the d'tor which destroys the notifier first, completing the message
sl@0: //
sl@0: void CDbsObserver::DoCancel()
sl@0: 	{
sl@0: 	__ASSERT(iStatus!=KRequestPending);
sl@0: 	}
sl@0: 
sl@0: // Class CDbsDatabaseStub
sl@0: 
sl@0: // This class is used as a stub object between the two phases of
sl@0: // authentication on a secure database
sl@0: 
sl@0: CDbsDatabaseStub* CDbsDatabaseStub::NewL()
sl@0: 	{
sl@0: 	return new(ELeave) CDbsDatabaseStub;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Authenticate the access, on success destroy this object and return the
sl@0: // real database interface object
sl@0: //
sl@0: CDbDatabase* CDbsDatabaseStub::AuthenticateL()
sl@0: 	{
sl@0: 	CDbSource& src=CDbsConnection::Source(*this).Source();
sl@0: 	CDbDatabase* db=src.AuthenticateL();
sl@0: 	Attach(db);
sl@0: 	Destroy(this);
sl@0: 	return db;
sl@0: 	}
sl@0: 
sl@0: // Class CDbsConnection
sl@0: 
sl@0: // The context for all interface objects residing in the server, which
sl@0: // owns a reference on the data source.
sl@0: 
sl@0: CDbsConnection::~CDbsConnection()
sl@0: 	{
sl@0: 	if (iSource)
sl@0: 		iSource->Close();
sl@0: 	}
sl@0: 
sl@0: 
sl@0: // Class CDbsSource
sl@0: 
sl@0: // The sharing point for databases in the server, this maintains access
sl@0: // to the CDbSource interface object, allowing multiple connections to the
sl@0: // same database.
sl@0: 
sl@0: //
sl@0: // Something has closed. Check if we are still needed, and delete if not
sl@0: //
sl@0: void CDbsSource::Closed()
sl@0: 	{
sl@0: 	__ASSERT(iConnections==0);
sl@0: 	iObserver=CDbsObserver::Collect(iObserver);
sl@0: 	if (!iObserver)
sl@0: 		delete this;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // A connection has been removed
sl@0: //
sl@0: void CDbsSource::Close()
sl@0: 	{
sl@0: 	__ASSERT(iConnections>0);
sl@0: 	__ASSERT(iSource);
sl@0: 	if (--iConnections==0)
sl@0: 		{	// last connection is closed
sl@0: 		CDbSource* s=iSource;
sl@0: 		iSource=0;
sl@0: 		CDbObject::Destroy(s);
sl@0: 		iLink.Deque();			// cannot connect this source again
sl@0: 		Closed();
sl@0: 		}
sl@0: 	}
sl@0: 
sl@0: CDbsSource::~CDbsSource()
sl@0: 	{
sl@0: 	__ASSERT(!iSource);
sl@0: 	__ASSERT(!iObserver);
sl@0: 	delete iName;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Construct a new source object from a database using the driver discovery
sl@0: //
sl@0: CDbsSource* CDbsSource::NewL(RFs& aFs,const TDesC& aSource)
sl@0: 	{
sl@0:     //The following two statements are here to check the file path and raise (if have to) 
sl@0:     //the same errors as they were raised before by the previous (DbDriver related) source code.
sl@0: 	::TEntry fileEntry;
sl@0: 	__LEAVE_IF_ERROR(aFs.Entry(aSource, fileEntry));
sl@0: 		
sl@0: 	const TDbFormat& fmt=KBuiltinDriver.iFormats[0];
sl@0: 	
sl@0: 	CDbsSource* self=new(ELeave) CDbsSource(fmt);
sl@0: 	CleanupStack::PushL(self);
sl@0: 	self->iName=aSource.AllocL();
sl@0: 	self->iSource=fmt.OpenL(aFs,aSource,TDbFormat::EReadWrite);
sl@0: 	CleanupStack::Pop();	// self
sl@0: 	return self;
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // [Create and] return the active observer of the data source
sl@0: //
sl@0: CDbsObserver::HObserver* CDbsSource::ObserverL()
sl@0: 	{
sl@0: 	__ASSERT(iSource);
sl@0: 	CDbsObserver* observer=iObserver;
sl@0: 	if (!observer)
sl@0: 		iObserver=observer=CDbsObserver::NewL(*this);
sl@0: 	return observer->ObserverL();
sl@0: 	}
sl@0: 
sl@0: //
sl@0: // Test to find an identical source, in order to share it
sl@0: //
sl@0: TBool CDbsSource::Is(const TDesC& aSource) const
sl@0: 	{
sl@0: 	if (iName->CompareF(aSource)!=0)
sl@0: 		return EFalse;
sl@0: 	
sl@0: 	  return ETrue;
sl@0: 	}
sl@0: 
sl@0: 
sl@0: // Class RDbsSources
sl@0: 
sl@0: // The collection of all shared sources in the server
sl@0: 
sl@0: //
sl@0: // Open a source for sharing
sl@0: //
sl@0: CDbsConnection* RDbsSources::OpenLC(RFs& aFs,const TDesC& aSource,const TDesC& /*aFormat*/)
sl@0: 	{
sl@0: 	CDbsConnection* connect=new(ELeave) CDbsConnection;
sl@0: 	CleanupStack::PushL(connect);
sl@0: 
sl@0:   // try and find the source already open
sl@0:   	TIter iter(iSources);
sl@0:   	CDbsSource* src;
sl@0:   	for (;;)
sl@0:   		{
sl@0:   		src=iter++;
sl@0:   		if (src==0)
sl@0:   			{	// not already open, have to open a new source
sl@0:   			src=CDbsSource::NewL(aFs,aSource);
sl@0:   			iSources.AddFirst(*src);
sl@0:   			break;
sl@0:   			}
sl@0:   		if (src->Is(aSource))
sl@0:   			break;	// share this source
sl@0:   		}
sl@0:   // we have a source
sl@0: 	connect->Set(*src);
sl@0: 	return connect;
sl@0: 	}
sl@0: