commsfwutils/commsbufs/reference/loopback_driver/ldd.cpp
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     1 // Copyright (c) 1999-2009 Nokia Corporation and/or its subsidiary(-ies).
       
     2 // All rights reserved.
       
     3 // This component and the accompanying materials are made available
       
     4 // under the terms of "Eclipse Public License v1.0"
       
     5 // which accompanies this distribution, and is available
       
     6 // at the URL "http://www.eclipse.org/legal/epl-v10.html".
       
     7 //
       
     8 // Initial Contributors:
       
     9 // Nokia Corporation - initial contribution.
       
    10 //
       
    11 // Contributors:
       
    12 //
       
    13 // Description:
       
    14 //
       
    15 
       
    16 #include <kernel/kern_priv.h>
       
    17 
       
    18 #ifdef SYMBIAN_OLD_EXPORT_LOCATION
       
    19 #include <comms-infras/legacy_loopback_driver.h>
       
    20 #else
       
    21 //this header is not exported, needs to be a user include
       
    22 #include "legacy_loopback_driver.h"
       
    23 #endif
       
    24 
       
    25 #include "device.h"
       
    26 
       
    27 _LIT(KESockLoopbackPanicCategory,"ESockLoopback");
       
    28 
       
    29 
       
    30 
       
    31 /**
       
    32   Standard export function for LDDs. This creates a DLogicalDevice derived object,
       
    33   in this case, our DESockLoopbackFactory
       
    34 */
       
    35 DECLARE_STANDARD_LDD()
       
    36 	{
       
    37 	return new DESockLoopbackFactory;
       
    38 	}
       
    39 
       
    40 /**
       
    41   Constructor
       
    42 */
       
    43 DESockLoopbackFactory::DESockLoopbackFactory()
       
    44 	{
       
    45 	// Set version number for this device
       
    46 	iVersion=RLegacyLoopbackDriver::VersionRequired();
       
    47 	// Indicate that we work with a PDD
       
    48 	iParseMask=KDeviceAllowPhysicalDevice;
       
    49 	}
       
    50 
       
    51 
       
    52 /**
       
    53   Second stage constructor for DESockLoopbackFactory.
       
    54   This must at least set a name for the driver object.
       
    55 
       
    56   @return KErrNone if successful, otherwise one of the other system wide error codes.
       
    57 */
       
    58 TInt DESockLoopbackFactory::Install()
       
    59 	{
       
    60 	return SetName(&RLegacyLoopbackDriver::Name());
       
    61 	}
       
    62 
       
    63 DESockLoopbackFactory::~DESockLoopbackFactory()
       
    64    	{
       
    65    	}
       
    66 
       
    67 /**
       
    68   Return the drivers capabilities.
       
    69   Called in the response to an RDevice::GetCaps() request.
       
    70 
       
    71   @param aDes User-side descriptor to write capabilities information into
       
    72 */
       
    73 void DESockLoopbackFactory::GetCaps(TDes8& aDes) const
       
    74 	{
       
    75 	// Create a capabilities object
       
    76 	RLegacyLoopbackDriver::TCaps caps;
       
    77 	caps.iVersion = iVersion;
       
    78 	// Write it back to user memory
       
    79 	Kern::InfoCopy(aDes,(TUint8*)&caps,sizeof(caps));
       
    80 	}
       
    81 
       
    82 /**
       
    83   Called by the kernel's device driver framework to create a Logical Channel.
       
    84   This is called in the context of the user thread (client) which requested the creation of a Logical Channel
       
    85   (E.g. through a call to RBusLogicalChannel::DoCreate)
       
    86   The thread is in a critical section.
       
    87 
       
    88   @param aChannel Set to point to the created Logical Channel
       
    89 
       
    90   @return KErrNone if successful, otherwise one of the other system wide error codes.
       
    91 */
       
    92 TInt DESockLoopbackFactory::Create(DLogicalChannelBase*& aChannel)
       
    93 	{
       
    94 	aChannel=new DESockLoopbackChannel;
       
    95 	if(!aChannel)
       
    96 		return KErrNoMemory;
       
    97 
       
    98 	return KErrNone;
       
    99 	}
       
   100 
       
   101 DESockLoopbackChannel::DESockLoopbackChannel()
       
   102 	:	iSendDataDfc(SendDataDfc, this, 1),        // DFC is priority '1'
       
   103 		iReceiveDataDfc(ReceiveDataDfc, this, 1)   // DFC is priority '1'
       
   104 	{
       
   105 	// Get pointer to client threads DThread object
       
   106 	iClient=&Kern::CurrentThread();
       
   107 
       
   108 	// Open a reference on client thread so it's control block can't dissapear until
       
   109 	// this driver has finished with it.
       
   110 	// Note, this call to Open can't fail since its the thread we are currently running in
       
   111 	iClient->Open();
       
   112 	memclr(&iDebugProbes, sizeof(iDebugProbes));
       
   113 	Kern::Printf("clearing probe points\n");
       
   114 	}
       
   115 
       
   116 /**
       
   117   Second stage constructor called by the kernel's device driver framework.
       
   118   This is called in the context of the user thread (client) which requested the creation of a Logical Channel
       
   119   (E.g. through a call to RBusLogicalChannel::DoCreate)
       
   120   The thread is in a critical section.
       
   121 
       
   122   @param aUnit The unit argument supplied by the client to RBusLogicalChannel::DoCreate
       
   123   @param aInfo The info argument supplied by the client to RBusLogicalChannel::DoCreate
       
   124   @param aVer The version argument supplied by the client to RBusLogicalChannel::DoCreate
       
   125 
       
   126   @return KErrNone if successful, otherwise one of the other system wide error codes.
       
   127 */
       
   128 TInt DESockLoopbackChannel::DoCreate(TInt /*aUnit*/, const TDesC8* /*aInfo*/, const TVersion& aVer)
       
   129 	{
       
   130 	// Check Platform Security capabilities of client thread (if required).
       
   131 	//
       
   132 	// Here we handle the simple case where:
       
   133 	// 1. The device driver can only have one client thread
       
   134 	// 2. The security policy is the binary all-or-nothing policy.
       
   135 	//    E.g. "If you have the right capability you can do anything with the driver
       
   136 	//    and if you don't have the capability you can't do anything"
       
   137 	// 
       
   138 	// If only some functionality of the driver is restricted, then the security check should
       
   139 	// go elsewhere. E.g. in DoRequest/DoControl. In that case Kern::CurrentThreadHasCapability
       
   140 	// shouldn't be used because the 'current thread' isn't the client.
       
   141 	//
       
   142 	// In this example we do a check here for ECapability_None (which always passes)...
       
   143 	if(!Kern::CurrentThreadHasCapability(ECapability_None,__PLATSEC_DIAGNOSTIC_STRING("Checked by ESockLoopback")))
       
   144 		return KErrPermissionDenied;
       
   145 
       
   146 	// Check version
       
   147 	if (!Kern::QueryVersionSupported(RLegacyLoopbackDriver::VersionRequired(),aVer))
       
   148 		return KErrNotSupported;
       
   149 
       
   150 	// Setup LDD for receiving client messages
       
   151 	SetDfcQ(((DESockLoopbackPddFactory*)iPhysicalDevice)->iDfcQ);
       
   152 	iMsgQ.Receive();
       
   153 
       
   154 	// Associate DFCs with the same queue we set above to receive client messages on
       
   155 	iSendDataDfc.SetDfcQ(iDfcQ);
       
   156 	iReceiveDataDfc.SetDfcQ(iDfcQ);
       
   157 
       
   158 	// Give PDD a pointer to this channel
       
   159 	Pdd()->iLdd=this;
       
   160 
       
   161 	// Done
       
   162 	return KErrNone;
       
   163 	}
       
   164 
       
   165 #define PRINT_PROBE_POINTS(name) \
       
   166 	{\
       
   167 	Kern::Printf("probe list:%s\n\t", name); \
       
   168 	for(TInt i = 0; i < (sizeof(iDebugProbes) / sizeof(TInt)); i++)\
       
   169 		{ \
       
   170 		Kern::Printf("%d:%d, ", i, iDebugProbes[i]); \
       
   171 		} \
       
   172 	Kern::Printf("\n\n"); \
       
   173 	}
       
   174 
       
   175 #define PROBE_LDD(index) (iDebugProbes[index]++)
       
   176 #define PROBE_LDD_STATIC(index, obj) (((obj)->iDebugProbes[index])++)
       
   177 
       
   178 DESockLoopbackChannel::~DESockLoopbackChannel()
       
   179 	{
       
   180 	// Cancel all processing that we may be doing
       
   181 	DoCancel(RLegacyLoopbackDriver::EAllRequests);
       
   182 	// Close our reference on the client thread
       
   183 	Kern::SafeClose((DObject*&)iClient,NULL);
       
   184 	}
       
   185 
       
   186 /**
       
   187   Called when a user thread requests a handle to this channel.
       
   188 */
       
   189 TInt DESockLoopbackChannel::RequestUserHandle(DThread* aThread, TOwnerType aType)
       
   190 	{
       
   191 	// Make sure that only our client can get a handle
       
   192 	if (aType!=EOwnerThread || aThread!=iClient)
       
   193 		return KErrAccessDenied;
       
   194 	return KErrNone;
       
   195 	}
       
   196 
       
   197 /**
       
   198   Process a message for this logical channel.
       
   199   This function is called in the context of a DFC thread.
       
   200 
       
   201   @param aMessage The message to process.
       
   202 	              The iValue member of this distinguishes the message type:
       
   203 	              iValue==ECloseMsg, channel close message
       
   204 	              iValue==KMaxTInt, a 'DoCancel' message
       
   205 	              iValue>=0, a 'DoControl' message with function number equal to iValue
       
   206 	              iValue<0, a 'DoRequest' message with function number equal to ~iValue
       
   207 */
       
   208 void DESockLoopbackChannel::HandleMsg(TMessageBase* aMsg)
       
   209 	{
       
   210 	TThreadMessage& m=*(TThreadMessage*)aMsg;
       
   211 
       
   212 	// Get message type
       
   213 	TInt id=m.iValue;
       
   214 
       
   215 	// Decode the message type and dispatch it to the relevent handler function...
       
   216 
       
   217 	if (id==(TInt)ECloseMsg)
       
   218 		{
       
   219 		// Channel Close
       
   220 		PRINT_PROBE_POINTS("ldd");
       
   221 		DoCancel(RLegacyLoopbackDriver::EAllRequests);
       
   222 		m.Complete(KErrNone, EFalse);
       
   223 		return;
       
   224 		}
       
   225 
       
   226 	if (id==KMaxTInt)
       
   227 		{
       
   228 		// DoCancel
       
   229 		DoCancel(m.Int0());
       
   230 		m.Complete(KErrNone,ETrue);
       
   231 		return;
       
   232 		}
       
   233 
       
   234 	if (id<0)
       
   235 		{
       
   236 		// DoRequest
       
   237 		TRequestStatus* pS=(TRequestStatus*)m.Ptr0();
       
   238 		TInt r=DoRequest(~id,pS,m.Ptr1(),m.Ptr2());
       
   239 		if (r!=KErrNone)
       
   240 			{
       
   241 			Kern::RequestComplete(iClient,pS,r);
       
   242 			}
       
   243 		m.Complete(KErrNone,ETrue);
       
   244 		}
       
   245 	else
       
   246 		{
       
   247 		// DoControl
       
   248 		TInt r=DoControl(id,m.Ptr0(),m.Ptr1());
       
   249 		m.Complete(r,ETrue);
       
   250 		}
       
   251 	}
       
   252 
       
   253 /**
       
   254   Process synchronous 'control' requests
       
   255 */
       
   256 TInt DESockLoopbackChannel::DoControl(TInt aFunction, TAny* a1, TAny* a2)
       
   257 	{
       
   258 	(void)a2;   // a2 not used in this example
       
   259 
       
   260 	TInt r;
       
   261 
       
   262 	switch (aFunction)
       
   263 		{
       
   264 		case RLegacyLoopbackDriver::EGetConfig:
       
   265 			r = GetConfig((TDes8*)a1);
       
   266 			break;
       
   267 
       
   268 		case RLegacyLoopbackDriver::ESetConfig:
       
   269 			r = SetConfig((const TDesC8*)a1);
       
   270 			break;
       
   271 
       
   272 		default:
       
   273 			r = KErrNotSupported;
       
   274 			break;
       
   275 		}
       
   276 
       
   277 	return r;
       
   278 	}
       
   279 
       
   280 /**
       
   281   Process asynchronous requests.
       
   282 */
       
   283 TInt DESockLoopbackChannel::DoRequest(TInt aReqNo, TRequestStatus* aStatus, TAny* a1, TAny* a2)
       
   284 	{
       
   285 	(void)a2;   // a2 not used in this example
       
   286 
       
   287 	TInt r;
       
   288 
       
   289 	switch(aReqNo)
       
   290 		{
       
   291 		case RLegacyLoopbackDriver::ESendData:
       
   292 			r=SendData(aStatus,(const TDesC8*)a1);
       
   293 			break;
       
   294 
       
   295 		case RLegacyLoopbackDriver::EReceiveData:
       
   296 			// Example Platform Security capability check which tests the
       
   297 			// client for ECapability_None (which always passes)...
       
   298 			if(iClient->HasCapability(ECapability_None,__PLATSEC_DIAGNOSTIC_STRING("Checked by ESockLoopback")))
       
   299 				r=ReceiveData(aStatus,(TDes8*)a1);
       
   300 			else
       
   301 				r=KErrPermissionDenied;
       
   302 			break;
       
   303 
       
   304 		default:
       
   305 			r = KErrNotSupported;
       
   306 			break;
       
   307 		}
       
   308 
       
   309 	return r;
       
   310 	}
       
   311 
       
   312 /**
       
   313   Process cancelling of asynchronous requests.
       
   314 */
       
   315 void DESockLoopbackChannel::DoCancel(TUint aMask)
       
   316 	{
       
   317 	if(aMask&(1<<RLegacyLoopbackDriver::ESendData))
       
   318 		SendDataCancel();
       
   319 	if(aMask&(1<<RLegacyLoopbackDriver::EReceiveData))
       
   320 		ReceiveDataCancel();
       
   321 	}
       
   322 
       
   323 /**
       
   324   Process a GetConfig control message. This writes the current driver configuration to a
       
   325   RLegacyLoopbackDriver::TConfigBuf supplied by the client.
       
   326 */
       
   327 TInt DESockLoopbackChannel::GetConfig(TDes8* aConfigBuf)
       
   328 	{
       
   329 	// Create a structure giving the current configuration
       
   330 	RLegacyLoopbackDriver::TConfig config;
       
   331 	CurrentConfig(config);
       
   332 
       
   333 	// Write the config to the client
       
   334 	TPtrC8 ptr((const TUint8*)&config,sizeof(config));
       
   335 	return Kern::ThreadDesWrite(iClient,aConfigBuf,ptr,0,KTruncateToMaxLength,NULL);
       
   336 	}
       
   337 
       
   338 /**
       
   339   Process a SetConfig control message. This sets the driver configuration using a
       
   340   RLegacyLoopbackDriver::TConfigBuf supplied by the client.
       
   341 */
       
   342 TInt DESockLoopbackChannel::SetConfig(const TDesC8* aConfigBuf)
       
   343 	{
       
   344 	// Don't allow configuration changes whilst we're busy
       
   345 	if(iSendDataStatus || iReceiveDataStatus)
       
   346 		return KErrInUse;
       
   347 
       
   348 	// Create a config structure.
       
   349 	RLegacyLoopbackDriver::TConfig config;
       
   350 	CurrentConfig(config);
       
   351 
       
   352 	// Note: We have filled config with the current settings, this is to allow
       
   353 	// backwards compatibility when a client gives us an old (and shorter) version
       
   354 	// of the config structure.
       
   355 
       
   356 	// Read the config structure from client
       
   357 	TPtr8 ptr((TUint8*)&config,sizeof(config));
       
   358 	TInt r=Kern::ThreadDesRead(iClient,aConfigBuf,ptr,0);
       
   359 	if(r!=KErrNone)
       
   360 		return r;
       
   361 
       
   362 	// Use config data to setup the driver. Checking that parameters which aren't settable
       
   363 	// either contain the correct values or are zero (meaning 'default')
       
   364 	if(config.iPddBufferSize && config.iPddBufferSize!=Pdd()->BufferSize())
       
   365 		return KErrArgument;
       
   366 
       
   367 	if(config.iMaxSendDataSize && config.iMaxSendDataSize!=KLoopbackMTU)
       
   368 		return KErrArgument;
       
   369 
       
   370 	if(config.iMaxReceiveDataSize && config.iMaxReceiveDataSize!=KLoopbackMTU)
       
   371 		return KErrArgument;
       
   372 
       
   373 	r=Pdd()->SetSpeed(config.iSpeed);
       
   374 	if(r!=KErrNone)
       
   375 		return r;
       
   376 
       
   377 	return r;
       
   378 	}
       
   379 
       
   380 /**
       
   381   Fill a TConfig with the drivers current configuration.
       
   382 */
       
   383 void DESockLoopbackChannel::CurrentConfig(RLegacyLoopbackDriver::TConfig& aConfig)
       
   384 	{
       
   385 	aConfig.iSpeed = Pdd()->Speed();
       
   386 	aConfig.iPddBufferSize = Pdd()->BufferSize();
       
   387 	aConfig.iMaxSendDataSize = KLoopbackMTU;
       
   388 	aConfig.iMaxReceiveDataSize = KLoopbackMTU;
       
   389 	}
       
   390 
       
   391 /**
       
   392   Start processing a SendData request.
       
   393 */
       
   394 TInt DESockLoopbackChannel::SendData(TRequestStatus* aStatus,const TDesC8* aData)
       
   395 	{
       
   396 	// Check that a 'SendData' isn't already in progress
       
   397 	PROBE_LDD(0);
       
   398 	if(iSendDataStatus)
       
   399 		{
       
   400 		Kern::ThreadKill(iClient,EExitPanic,ERequestAlreadyPending,KESockLoopbackPanicCategory);
       
   401 		return KErrInUse;
       
   402 		}
       
   403 	
       
   404 	// Read data from client into our buffer
       
   405 	TInt r=Kern::ThreadDesRead(iClient,aData,Pdd()->SendBuffer(),0);
       
   406 	if(r!=KErrNone)
       
   407 		return r;
       
   408 
       
   409 	// Give data to PDD so that it can do the work
       
   410 	r=Pdd()->RequestDataSend();
       
   411 	if(r!=KErrNone)
       
   412 		return r;
       
   413 
       
   414 	// Save the client request status and return
       
   415 	PROBE_LDD(1);
       
   416 	iSendDataStatus = aStatus;
       
   417 	return KErrNone;
       
   418 	}
       
   419 
       
   420 /**
       
   421   Cancel a SendData request.
       
   422 */
       
   423 void DESockLoopbackChannel::SendDataCancel()
       
   424 	{
       
   425 	if(iSendDataStatus)
       
   426 		{
       
   427 		// Tell PDD to stop processing the request
       
   428 		Pdd()->SendDataCancel();
       
   429 
       
   430 		// Cancel DFC
       
   431 		iSendDataDfc.Cancel();
       
   432 
       
   433 		// Complete clients request
       
   434 		Kern::RequestComplete(iClient,iSendDataStatus,KErrCancel);
       
   435 		}
       
   436 	}
       
   437 
       
   438 /**
       
   439   Called by PDD from ISR to indicate that a SendData operation has completed.
       
   440 */
       
   441 void DESockLoopbackChannel::SendDataComplete(TInt aResult)
       
   442 	{
       
   443 	PROBE_LDD(2);
       
   444 	// Save result code
       
   445 	iSendDataResult = aResult;
       
   446 
       
   447 	// Queue DFC
       
   448 	iSendDataDfc.Add();
       
   449 	}
       
   450 
       
   451 /**
       
   452   DFC callback which gets triggered after the PDD has signalled that SendData completed.
       
   453   This just casts aPtr and calls DoSendDataComplete().
       
   454 */
       
   455 void DESockLoopbackChannel::SendDataDfc(TAny* aPtr)
       
   456 	{
       
   457 	PROBE_LDD_STATIC(3, ((DESockLoopbackChannel*)aPtr));
       
   458 	((DESockLoopbackChannel*)aPtr)->DoSendDataComplete();
       
   459 	}
       
   460 
       
   461 /**
       
   462   Called from a DFC after the PDD has signalled that SendData completed.
       
   463 */
       
   464 void DESockLoopbackChannel::DoSendDataComplete()
       
   465 	{
       
   466 	TInt result = iSendDataResult;
       
   467 
       
   468 	// Complete clients request
       
   469 	Kern::RequestComplete(iClient,iSendDataStatus,result);
       
   470 	}
       
   471 
       
   472 /**
       
   473   Start processing a ReceiveData request.
       
   474 */
       
   475 TInt DESockLoopbackChannel::ReceiveData(TRequestStatus* aStatus,TDes8* aPtr)
       
   476 	{
       
   477 	PROBE_LDD(4);
       
   478 	// Check that a 'ReceiveData' isn't already in progress
       
   479 	if(iReceiveDataStatus)
       
   480 		{
       
   481 		Kern::ThreadKill(iClient,EExitPanic,ERequestAlreadyPending,KESockLoopbackPanicCategory);
       
   482 		return KErrInUse;
       
   483 		}
       
   484 	
       
   485 	// Save the client request status and descriptor for later completion
       
   486 	iReceiveDataStatus = aStatus;
       
   487 	iReceiveDataDescriptor = aPtr;
       
   488 	
       
   489 	if(Pdd()->ReceivedQueueLen() > 0)
       
   490 		{
       
   491 		// complete with waiting data
       
   492 		DoReceiveDataComplete();
       
   493 		}
       
   494 
       
   495 	// Ask PDD for data
       
   496 	NKern::Lock(); 
       
   497 	TInt r = Pdd()->RequestDataReceipt();
       
   498 	NKern::Unlock(); 
       
   499 
       
   500 	if(r != KErrNone)
       
   501 		{
       
   502 		iReceiveDataDescriptor = NULL;
       
   503 		return r;
       
   504 		}
       
   505 
       
   506 	PROBE_LDD(5);
       
   507 	return KErrNone;
       
   508 	}
       
   509 
       
   510 /**
       
   511   Cancel a ReceiveData request.
       
   512 */
       
   513 void DESockLoopbackChannel::ReceiveDataCancel()
       
   514 	{
       
   515 	if(iReceiveDataStatus)
       
   516 		{
       
   517 		// Tell PDD to stop processing the request
       
   518 		Pdd()->ReceiveDataCancel();
       
   519 
       
   520 		// Cancel DFC
       
   521 		iReceiveDataDfc.Cancel();
       
   522 
       
   523 		// Finished with client descriptor, so NULL it to help detect coding errors
       
   524 		iReceiveDataDescriptor = NULL;
       
   525 
       
   526 		// Complete clients request
       
   527 		Kern::RequestComplete(iClient,iReceiveDataStatus,KErrCancel);
       
   528 		}
       
   529 	}
       
   530 
       
   531 /**
       
   532   Called by PDD from ISR to indicate that a ReceiveData operation has completed.
       
   533 */
       
   534 void DESockLoopbackChannel::ReceiveDataComplete(TInt aResult)
       
   535 	{
       
   536 	PROBE_LDD(6);
       
   537 	// Save result code
       
   538 	iReceiveDataResult = aResult;
       
   539 
       
   540 	// Queue DFC
       
   541 	NKern::Lock(); 
       
   542 	iReceiveDataDfc.Add();
       
   543 	NKern::Unlock(); 
       
   544 	}
       
   545 
       
   546 /**
       
   547   DFC Callback which gets triggered after the PDD has signalled that ReceiveData completed.
       
   548   This just casts aPtr and calls DoReceiveDataComplete().
       
   549 */
       
   550 void DESockLoopbackChannel::ReceiveDataDfc(TAny* aPtr)
       
   551 	{
       
   552 	PROBE_LDD_STATIC(7, ((DESockLoopbackChannel*)aPtr));
       
   553 	((DESockLoopbackChannel*)aPtr)->DoReceiveDataComplete();
       
   554 	}
       
   555 
       
   556 /**
       
   557   Called from a DFC after the PDD has signalled that ReceiveData completed.
       
   558 */
       
   559 void DESockLoopbackChannel::DoReceiveDataComplete()
       
   560 	{
       
   561 	if(iReceiveDataStatus)
       
   562 		{
       
   563 		PROBE_LDD(8);
       
   564 
       
   565 		// Write data to client from our buffer
       
   566 		TInt result = Kern::ThreadDesWrite(iClient, iReceiveDataDescriptor, Pdd()->ReceiveBuffer(), 0);
       
   567 
       
   568 		// Finished with client descriptor, so NULL it to help detect coding errors
       
   569 		iReceiveDataDescriptor = NULL;
       
   570 
       
   571 		// Step the receive queue
       
   572 		Pdd()->AdvanceReceiveQueue();
       
   573 
       
   574 		// Use result code from PDD if it was an error
       
   575 		if(iReceiveDataResult != KErrNone)
       
   576 			result = iReceiveDataResult;
       
   577 
       
   578 		// Complete client's request
       
   579 		Kern::RequestComplete(iClient, iReceiveDataStatus, result);
       
   580 		}
       
   581 	}
       
   582 
       
   583