epoc32/include/mmf/server/mmfdatasink.h
branchSymbian2
changeset 2 2fe1408b6811
parent 0 061f57f2323e
child 4 837f303aceeb
     1.1 --- a/epoc32/include/mmf/server/mmfdatasink.h	Tue Nov 24 13:55:44 2009 +0000
     1.2 +++ b/epoc32/include/mmf/server/mmfdatasink.h	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -1,1 +1,361 @@
     1.4 -mmfdatasink.h
     1.5 +// Copyright (c) 2001-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.6 +// All rights reserved.
     1.7 +// This component and the accompanying materials are made available
     1.8 +// under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
     1.9 +// which accompanies this distribution, and is available
    1.10 +// at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
    1.11 +//
    1.12 +// Initial Contributors:
    1.13 +// Nokia Corporation - initial contribution.
    1.14 +//
    1.15 +// Contributors:
    1.16 +//
    1.17 +// Description:
    1.18 +// include\mmf\server\mmfdatasink.h
    1.19 +// 
    1.20 +//
    1.21 +
    1.22 +#ifndef __MMF_SERVER_DATASINK_H__
    1.23 +#define __MMF_SERVER_DATASINK_H__
    1.24 +
    1.25 +#include <e32base.h>
    1.26 +#include <mmf/server/mmfdatasourcesink.hrh>
    1.27 +#include <mmf/common/mmfutilities.h>
    1.28 +#include <ecom/ecom.h>
    1.29 +#include <mmf/common/mmfbase.h>
    1.30 +#include <mmf/common/mmfcontrollerframework.h>
    1.31 +
    1.32 +//
    1.33 +// MDataSink mixim
    1.34 +//
    1.35 +
    1.36 +class TFourCC;
    1.37 +class TMediaId;
    1.38 +class CMMFBuffer;
    1.39 +class MDataSource;
    1.40 +class MAsyncEventHandler;
    1.41 +
    1.42 +/**
    1.43 +@publishedAll
    1.44 +@released
    1.45 +
    1.46 +Abstract class representing a data sink.
    1.47 +*/
    1.48 +class MDataSink
    1.49 +	{
    1.50 +public:
    1.51 +
    1.52 +	static inline MDataSink* NewSinkL( TUid aImplementationUid,  const TDesC8& aInitData ) ;
    1.53 +
    1.54 +	/**
    1.55 +	Destructor.
    1.56 +	*/
    1.57 +	virtual ~MDataSink() {REComSession::DestroyedImplementation(iDtor_ID_Key);};
    1.58 +
    1.59 +	/**
    1.60 +	Returns the UID identifying the type of data sink.
    1.61 +
    1.62 +	@return The UID identifying the type of data sink
    1.63 +	*/
    1.64 +	virtual TUid DataSinkType() const {return iDataSinkType;};
    1.65 +
    1.66 +	/**
    1.67 +	Returns the data type as a fourCC code of the data sink.
    1.68 +
    1.69 +	This is a pure virtual function that each derrived class must implement.
    1.70 +
    1.71 +	@param  aMediaId
    1.72 +	        This identifies the type of media eg. audio or video and the stream ID.
    1.73 +	        This parameter is required in cases where the sink can accept data
    1.74 +	        of more than one media type and/or multiple streams of data.
    1.75 +
    1.76 +	@return The fourCC code identifying the sink datatype for the specified aMediaId.
    1.77 +	*/
    1.78 +	virtual TFourCC SinkDataTypeCode(TMediaId aMediaId) = 0;
    1.79 +
    1.80 +	inline virtual TInt SetSinkDataTypeCode(TFourCC aSinkFourCC, TMediaId aMediaId);
    1.81 +
    1.82 +	/**
    1.83 +	Method called by a MDataSource to request the data sink to empty aBuffer of data.
    1.84 +
    1.85 +	This is a pure virtual function that each derived class must implement.
    1.86 +	This method is used when a data sink is passively waiting for requests from a supplier ie.
    1.87 +	a data source to empty a buffer. The data sink must call the BufferEmptiedL member on aSupplier 
    1.88 +	when it has emptied	the buffer of it's data. The data sink can either make this callback 
    1.89 +	synchronously or asynchronously.
    1.90 +
    1.91 +	@param  aBuffer
    1.92 +	        The full buffer that needs emptying of it's data.
    1.93 +	@param  aSupplier
    1.94 +	        The data source that supplied the data. The data sink needs this to make the 
    1.95 +	        BufferEmptiedL callback on aSupplier to indicate to the data source that the data sink
    1.96 +	        has finished with the buffer.
    1.97 +	@param  aMediaId
    1.98 +	        This identifies the type of media eg. audio or video and the stream ID.
    1.99 +	        This parameter is required in cases where the source can supply data
   1.100 +	        of more than one media type and/or multiple streams of data.
   1.101 +	*/
   1.102 +	virtual void EmptyBufferL(CMMFBuffer* aBuffer, MDataSource* aSupplier, TMediaId aMediaId)=0;
   1.103 +
   1.104 +	/**
   1.105 +	Function called by a data source to pass back a filled buffer to the sink.
   1.106 +
   1.107 +	This is a pure virtual function that each derived class must implement.
   1.108 +	This method is used as the callback when the data sink actively requests a supplier ie. a
   1.109 +	data source	to fill a buffer by calling the data sources FillBufferL. When the data sink gets
   1.110 +	this callback it knows that the buffer has been filled and is ready to be emptied.
   1.111 +
   1.112 +	@param  aBuffer
   1.113 +	        The buffer that has been filled by a data source and is now available for processing.
   1.114 +	*/
   1.115 +	virtual void BufferFilledL(CMMFBuffer* aBuffer)=0;
   1.116 +	
   1.117 +	/**
   1.118 +	@deprecated
   1.119 +
   1.120 +	Function to indicate whether the data sink can create a buffer.
   1.121 +
   1.122 +	This is a pure virtual function that each derived class must implement.
   1.123 +
   1.124 +	@return	A boolean indicating if the data sink can create a buffer. ETrue if it can otherwise 
   1.125 +	        EFalse.
   1.126 +	*/
   1.127 +	virtual TBool CanCreateSinkBuffer()=0;
   1.128 +	
   1.129 +	/**
   1.130 +	Returns a buffer created by the data sink.
   1.131 +
   1.132 +	This is a pure virtual function that each derived class must implement.
   1.133 +
   1.134 +	@param  aMediaId
   1.135 +	        This identifies the type of media eg. audio or video and the stream ID.
   1.136 +	        This parameter is required in cases where the source can supply data
   1.137 +	        of more than one media type and/or multiple streams of data.
   1.138 +
   1.139 +	@param  aReference
   1.140 +	        This must be written to by the method to indicate whether the created buffer is
   1.141 +	        a 'reference' buffer.  A 'reference' buffer is a buffer that is owned by the sink
   1.142 +	        and should be used in preference to the source buffer provided the source buffer
   1.143 +	        is also not a reference buffer.
   1.144 +
   1.145 +	@return	The created buffer.
   1.146 +	*/
   1.147 +	virtual CMMFBuffer* CreateSinkBufferL(TMediaId aMediaId, TBool &aReference)=0;
   1.148 +
   1.149 +	inline virtual TInt SinkThreadLogon(MAsyncEventHandler& aEventHandler);
   1.150 +
   1.151 +	/**
   1.152 +	Function to 'logoff' the data sink from the same thread that sink consumes data in.
   1.153 +
   1.154 +	This method may be required as the thread that the data sink is deleted in may not be
   1.155 +	the same thread that the data transfer took place in.  Therefore any thread specific
   1.156 +	releasing of resources needs to be performed in the SinkThreadLogoff rather than in the
   1.157 +	destructor.
   1.158 +
   1.159 +	This is a virtual function that a derrived data sink can implement if any thread specific
   1.160 +	releasing of resources is required.
   1.161 +	*/
   1.162 +	virtual void SinkThreadLogoff() {};
   1.163 +
   1.164 +	inline virtual void NegotiateL(MDataSource& aDataSource);
   1.165 +
   1.166 +	/**
   1.167 +	Function to 'prime' the data sink.
   1.168 +
   1.169 +	This is a virtual function that a derrived data sink can implement if
   1.170 +	any data sink specific 'priming' is required.
   1.171 +	*/
   1.172 +	virtual void SinkPrimeL() {};
   1.173 +
   1.174 +	/**
   1.175 +	Function 'play' the data sink.
   1.176 +
   1.177 +	This is a virtual function that a derrived data sink can implement if
   1.178 +	any data sink specific action is required prior to 'playing' ie. the start of data transfer.
   1.179 +	*/
   1.180 +	virtual void SinkPlayL() {};
   1.181 +
   1.182 +	/**
   1.183 +	Function to 'pause' the data sink.
   1.184 +
   1.185 +	This is a virtual function that a derrived data sink can implement if
   1.186 +	any data sink specific action is required to 'pause'.
   1.187 +	*/
   1.188 +	virtual void SinkPauseL() {};
   1.189 +
   1.190 +	/**
   1.191 +	Function to 'stop' the data sink.
   1.192 +
   1.193 +	This is a virtual function that a derrived data sink can implement if
   1.194 +	any data sink specific action is required to 'stop'
   1.195 +	*/
   1.196 +	virtual void SinkStopL() {};
   1.197 +
   1.198 +	inline virtual void SetSinkPrioritySettings(const TMMFPrioritySettings& aPrioritySettings);
   1.199 +
   1.200 +	/**
   1.201 +	Calls a sink specific custom command.
   1.202 +
   1.203 +	This is a virtual function that a derrived data sink can implement if
   1.204 +	it implements any custom commands.
   1.205 +
   1.206 +	@param  aMessage
   1.207 +	        The message specifying the custom command.
   1.208 +	*/
   1.209 +	virtual void SinkCustomCommand(TMMFMessage& aMessage) {aMessage.Complete(KErrNotSupported);};
   1.210 +	
   1.211 +protected:
   1.212 +	/**
   1.213 +	Performs any sink construction dependant on the sink construction
   1.214 +	initialisation data aInitData.
   1.215 +
   1.216 +	This is a pure virtual function that a derrived data sink must implement
   1.217 +
   1.218 +	@param  aInitData
   1.219 +	        The sink specific initialisation data required for sink construction.
   1.220 +	*/
   1.221 +	virtual void ConstructSinkL( const TDesC8& aInitData ) = 0;
   1.222 +
   1.223 +	/**
   1.224 +	Protected constructor.
   1.225 +
   1.226 +	@param  aType
   1.227 +	        The source type UID.
   1.228 +	*/
   1.229 +	MDataSink(TUid aType): iDataSinkType(aType) {}
   1.230 +	
   1.231 +private:
   1.232 +	TUid iDataSinkType;
   1.233 +	TUid iDtor_ID_Key;
   1.234 +	};
   1.235 +
   1.236 +/**
   1.237 +Instantiates a new data sink.
   1.238 +
   1.239 +@param  aImplementationUid
   1.240 +        The UID identifying the data sink to be instantiated.
   1.241 +@param  aInitData
   1.242 +        The sink specific initialisation data required for sink construction.
   1.243 +
   1.244 +@return	A pointer to the instantiated data sink.
   1.245 +*/
   1.246 +inline MDataSink* MDataSink::NewSinkL( TUid aImplementationUid,  const TDesC8& aInitData )
   1.247 +	{
   1.248 +	MDataSink* retPtr = REINTERPRET_CAST( MDataSink*, REComSession::CreateImplementationL( aImplementationUid,
   1.249 +																			_FOFF(MDataSink, iDtor_ID_Key) ) ) ;
   1.250 +	CleanupDeletePushL(retPtr);
   1.251 +	retPtr->ConstructSinkL( aInitData ) ;
   1.252 +
   1.253 +	CleanupStack::Pop(retPtr);
   1.254 +	return retPtr ;
   1.255 +	}
   1.256 +
   1.257 +/**
   1.258 +Sets the data type as a fourCC code for the data sink.
   1.259 +
   1.260 +This is a virtual function that each derived class can implement if the data sink supports
   1.261 +the ability to have its data type set.
   1.262 +
   1.263 +@param  aSinkFourCC
   1.264 +        This specifies the data type as a fourCC code to set the sink to.
   1.265 +@param  aMediaId
   1.266 +        This identifies the type of media eg. audio or video and the stream ID.
   1.267 +        This parameter is required in cases where the source can supply data
   1.268 +        of more than one media type and/or multiple streams of data.
   1.269 +
   1.270 +@return	KErrNone if successful, KErrNotSupported if the sink does not support having
   1.271 +        it's data type set, otherwise a system wide error code.
   1.272 +*/
   1.273 +inline TInt MDataSink::SetSinkDataTypeCode(TFourCC /*aSinkFourCC*/, TMediaId /*aMediaId*/)
   1.274 +{
   1.275 +	return KErrNotSupported;
   1.276 +}
   1.277 +
   1.278 +/**
   1.279 +Function to 'logon' the data sink to the same thread that sink will be consuming data in.
   1.280 +
   1.281 +This method may be required as the thread that the data sink was created in is not always
   1.282 +the same thread that the data transfer will take place in.  Therefore any thread specific
   1.283 +initialisation needs to be performed in the SinkThreadLogon rather than in the creation
   1.284 +of the data sink.
   1.285 +
   1.286 +This is a virtual function that a derrived data sink can implement if any thread specific
   1.287 +initialisation is required and/or the data sink can create any asynchronous events.
   1.288 +
   1.289 +@param  aEventHandler
   1.290 +        This is an MAsyncEventHandler to handle asynchronous events that occur during the
   1.291 +        transfer of multimedia data. The event handler must be in the same thread as the data
   1.292 +        transfer thread - hence the reason it is passed in the SinkThreadLogon as opposed to
   1.293 +        say the constructor.
   1.294 +
   1.295 +@return An error code indicating if the function call was successful. KErrNone on success, otherwise
   1.296 +        another of the system-wide error codes.
   1.297 +*/
   1.298 +inline TInt MDataSink::SinkThreadLogon(MAsyncEventHandler& /*aEventHandler*/)
   1.299 +{
   1.300 +	return KErrNone;
   1.301 +}
   1.302 +
   1.303 +/**
   1.304 +@deprecated
   1.305 +
   1.306 +Allows the data sink to negotiate with a data source.
   1.307 +
   1.308 +This method is required in cases where the settings of data sink are dependant on those of a
   1.309 +data source. This is a virtual function that a derrived data sink can implement.
   1.310 +
   1.311 +@param  aDataSource
   1.312 +        The data source whose settings can affect the data sink.
   1.313 +*/
   1.314 +inline void MDataSink::NegotiateL(MDataSource& /*aDataSource*/)
   1.315 +{
   1.316 +}
   1.317 +
   1.318 +/**
   1.319 +Sets the sink priority settings.
   1.320 +
   1.321 +This is a virtual function that a derrived data sink can implement if
   1.322 +a priority mechanism is required to arbitrate between multiple clients
   1.323 +trying to access the same resource.
   1.324 +
   1.325 +@param  aPrioritySettings
   1.326 +        The sink priority settings.
   1.327 +
   1.328 +@capability MultimediaDD
   1.329 +            A process requesting or using this method that has MultimediaDD capability will
   1.330 +			always have precedence over a process that does not have MultimediaDD.
   1.331 +*/
   1.332 +inline void MDataSink::SetSinkPrioritySettings(const TMMFPrioritySettings& /*aPrioritySettings*/)
   1.333 +{
   1.334 +}
   1.335 +
   1.336 +/**
   1.337 +This function is used by TCleanupItem objects to perform
   1.338 +a SinkStopL() when leaving functions exist, ususally between SinkPrimeL-SinkStopL pairs.
   1.339 +
   1.340 +@param  aSink
   1.341 +        The data sink to be stopped.
   1.342 +*/
   1.343 +inline static void DoDataSinkStop(TAny* aSink)
   1.344 +	{
   1.345 +	MDataSink* sink = STATIC_CAST(MDataSink*, aSink);
   1.346 +	// we don't want this function to leave because no leaving functions are supposed
   1.347 +	// to be used as argument to the TCleanupItem objects. Hence we catch the error but
   1.348 +	// we do nothing with it.
   1.349 +	TRAP_IGNORE(sink->SinkStopL());
   1.350 +	}
   1.351 +
   1.352 +/**
   1.353 +This method is used by TCleanupItem objects to perform a SinkThreadLogoff().
   1.354 +
   1.355 +@param  aSink
   1.356 +        The data sink to be logged off.
   1.357 +*/
   1.358 +inline static void DoDataSinkThreadLogoff(TAny* aSink)
   1.359 +	{
   1.360 +	MDataSink* sink = STATIC_CAST(MDataSink*, aSink);
   1.361 +	sink->SinkThreadLogoff();
   1.362 +	}
   1.363 +
   1.364 +
   1.365 +#endif