servicediscoverer.cpp

symbian系统下

/*
* ============================================================================
*  Name     : CServiceDiscoverer from ServiceDiscoverer.h
*  Part of  : BluetoothPMPExample
*  Created  : 06.06.2006 by Forum Nokia
*  Implementation notes:
*     Initial content was generated by Series 60 AppWizard.
*  Version  :
*  Copyright: Nokia Corporation
* ============================================================================
*/

// INCLUDE FILES
#include <btsdp.h>
#include "ServiceDiscoverer.h"


CServiceDiscoverer* CServiceDiscoverer::NewL(MServiceDiscoObserver& aObserver)
	{
	CServiceDiscoverer* self = CServiceDiscoverer::NewLC(aObserver);
    CleanupStack::Pop(self);
	return self;
	}


CServiceDiscoverer* CServiceDiscoverer::NewLC(MServiceDiscoObserver& aObserver)
	{
	CServiceDiscoverer* self = new (ELeave) CServiceDiscoverer(aObserver);
	CleanupStack::PushL(self);
	self->ConstructL();
	return self;
	}


void CServiceDiscoverer::ConstructL()
	{
	}

CServiceDiscoverer::CServiceDiscoverer(MServiceDiscoObserver& aObserver):
	iObserver(aObserver),
	iAgent(NULL),
	iSpat(NULL),
	iDiscoveredServiceCount(0)
	{
	}

CServiceDiscoverer::~CServiceDiscoverer()
	{ 
	iDiscoveredServiceCount=0;
	FinishDiscovery();
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::DiscoverServicesOnDeviceL(TDeviceData *aDevData)
//
// discover services on given device.  a service discovery agent will be
// started to do the discovery of services on given remote device.
// service discovery will be limited to search only for services with
// our service id.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::DiscoverServicesOnDeviceL(TDeviceData* aDevData)
	{
	if(iSpat)
		iSpat->Reset();
	delete iSpat;
	iSpat=NULL;

	if(iAgent)
		iAgent->Cancel();

	delete iAgent;
	iAgent=NULL;

	iDevDataChanged=EFalse;
	iDevData=aDevData;

	// init new service discovery agent
	iAgent = CSdpAgent::NewL( *this, iDevData->iDeviceAddr );
	// set search properties for agent
	iSpat = CSdpSearchPattern::NewL();
	// use our service id to filter the services discovered
	// -> will return only the services with matching service id(s)
	TUUID serviceUUID(KBT_serviceID);
	iSpat->AddL(serviceUUID);
	iAgent->SetRecordFilterL(*iSpat);

	// initiate search
	// this will result in call to NextRecordRequestComplete()
	iAgent->NextRecordRequestL();
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::DiscoverServicesL(TDeviceDataList* aDevDataList)
//
// discover services of all devices on the given device data list.  this will
// make the initial call to DiscoverServicesOnDeviceL(), the further calls
// to DiscoverServicesOnDeviceL() will be made by NextRecordRequestComplete()
// as the pending service discovery request completes.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::DiscoverServicesL(TDeviceDataList* aDevDataList)
	{
	if ( aDevDataList->Count()> 0 )
		{				
		iDeviceIdx=0;
		iDevDataList=aDevDataList;
		DiscoverServicesOnDeviceL((*iDevDataList)[iDeviceIdx]);
		}
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::FinishDiscovery()
//
// stop discovering services, stop service discovery agent.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::FinishDiscovery()
	{
	if(iAgent)
		iAgent->Cancel();
	delete iAgent;
	iAgent=NULL;
	if(iSpat)
		iSpat->Reset();
	delete iSpat;
	iSpat=NULL;
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::NextRecordRequestComplete(
//		TInt aError,
//		TSdpServRecordHandle aHandle,
//		TInt aTotalRecordsCount)
//
// called when the service discovery agent has completed discovering services
// on device.  now the attributes of the found service records (if any) must
// be evaluated.  if no service records were discovered, proceed doing 
// service discovery on next device.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::NextRecordRequestComplete(
	TInt aError,
	TSdpServRecordHandle aHandle,
	TInt aTotalRecordsCount)
	{
	if ( aError==KErrNone && aTotalRecordsCount>0 )	
		{
		// we got records, retrieve attributes for record
		// request protocol descriptor from remote device records,
		// we need this to retrieve remote port to connect to later on..
		TRAPD(err,iAgent->AttributeRequestL(aHandle, KSdpAttrIdProtocolDescriptorList) );
		if( err )
		    TRAP(err,iObserver.ReportServiceDiscoveryErrorL(err));
		}
	else 
		{
		// done with this device, store data if changed
		if ( iDevDataChanged )
			{
			iDevData->iDeviceServicePort=iPort;
			(*iDevDataList)[iDeviceIdx]=iDevData;
			iDiscoveredServiceCount++;
			}
		
		// discover services on next device, if any left
		iDeviceIdx++;
		if ( iDeviceIdx<iDevDataList->Count() )
			{
			// more devices to probe, proceed
			TRAPD(err,DiscoverServicesOnDeviceL((*iDevDataList)[iDeviceIdx]));
		    if( err )
		        TRAP(err,iObserver.ReportServiceDiscoveryErrorL(err))
			}
		else
			{
			FinishDiscovery();
			// all devices done, notify 
			TRAPD(err,iObserver.HandleServiceDiscoveryCompleteL());
			}
		}
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::AttributeRequestResult(
//		TSdpServRecordHandle /*aHandle*/,
//		TSdpAttributeID /*aAttrID*/,
//		CSdpAttrValue* aAttrValue)
//
// called when the service attributes for the service record have been 
// retrieved.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::AttributeRequestResult(
	TSdpServRecordHandle /*aHandle*/,
	TSdpAttributeID /*aAttrID*/,
	CSdpAttrValue* aAttrValue)
	{
	// parse attributes, will result in call to VisitAttributeValue()
	TRAPD(err,aAttrValue->AcceptVisitorL(*this) );
	if( err )
	    TRAP(err,iObserver.ReportServiceDiscoveryErrorL(err));
	
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::AttributeRequestComplete(
//		TSdpServRecordHandle /*aHandle*/, 
//		TInt aError)
//
// called when the request to resolve the service attributes for the service
// record completes.  if there are more service records, proceed resolving 
// the next service record.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::AttributeRequestComplete(
	TSdpServRecordHandle /*aHandle*/, 
	TInt aError)
	{
	if ( aError==KErrNone )
		{
		// done with attributes for this record, request next
		// service record
		TRAPD(err,iAgent->NextRecordRequestL());
		if( err )
		    TRAP(err,iObserver.ReportServiceDiscoveryErrorL(err));
		}
	else
		{
		// error, should terminate discoverer?
		}
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::VisitAttributeValueL(
//		CSdpAttrValue &aValue,
//		TSdpElementType aType)
//
// called for processing of each service attribute.  here we must look for 
// attributes of UUID type.  if the UUID is RFCOMM UUID, resolve the value
// for this attribute, which will be channel number to be used for connection
// to remote device.
// ----------------------------------------------------------------------------
void CServiceDiscoverer::VisitAttributeValueL(
	CSdpAttrValue &aValue,
	TSdpElementType aType)
	{
	switch (aType)	
		{
		case ETypeUUID:
			{
			TPtrC8 uuid(aValue.UUID().ShortestForm());
			iLastUUID.SetL(uuid);
			break;
			}

		case ETypeUint:
			{
			if ( iLastUUID==KRFCOMM )
			{
				// previous call to this method with rfcomm UUID, therefore
				// this one will be the value, rfcomm service channel (port)
				iPort=aValue.Uint();
				// mark device data changed, so the device data record in 
				// device data list will be updated.
				iDevDataChanged=ETrue;
			}
			break;
			}

		default:
			// rest don't really matter..
			break;

		}
	}


void CServiceDiscoverer::StartListL(CSdpAttrValueList& /*aList*/)
	{
	// not needed
	}

void CServiceDiscoverer::EndListL()
	{
	// not needed
	}


// ----------------------------------------------------------------------------
// CServiceDiscoverer::HasServices()
//
// returns true if any services matching our service id were found on any 
// remote device.
// ----------------------------------------------------------------------------
TBool CServiceDiscoverer::HasServices()
	{
	return ( iDiscoveredServiceCount>0 );
	}