1 // Copyright (c) 2002-2009 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 /**

    17  @file

    18  @internalComponent 

    19 */

    20 

    21 template<class TInfo, TInt QueueSize> TNotificationQueue<TInfo, QueueSize>::TNotificationQueue()

    22 /**

    23 Constructor

    24 */

    25 	: iQueueLength(0), iQueueStart(0)

    26 	{

    27 	}

    28 

    29 template<class TInfo, TInt QueueSize> void TNotificationQueue<TInfo, QueueSize>::Reset()

    30 /**

    31 Reset notification queue, throwing away any stored notifications

    32 */

    33 	{

    34 	iQueueLength = 0;

    35 	iQueueStart = 0;

    36 	}

    37 

    38 template<class TInfo, TInt QueueSize>

    39 void TNotificationQueue<TInfo, QueueSize>::ResetAndDestroy()

    40 /**

    41 Destroys the pointed memory cells and resets the queue.

    42 */

    43     {

    44     for (TUint i = 0; i < QueueSize; ++i)

    45         {

    46         delete iQueue[i];

    47         iQueue[i] = NULL;

    48         }

    49     Reset();

    50     }

    51 

    52 template<class TInfo, TInt QueueSize> void TNotificationQueue<TInfo, QueueSize>::Enque(const TInfo& aInfo)

    53 /**

    54 Place a InterfaceChange notification on the queue

    55 @param aInfo notification information

    56 */

    57 	{

    58 	TUint index;

    59 

    60 	if (IsEmpty())

    61 		{

    62 		index = iQueueStart;

    63 		iQueueLength++;

    64 		}

    65     else

    66 		{

    67 		index = (iQueueStart + iQueueLength) % QueueSize;

    68 

    69 		// Have we reached capacity?

    70 		if (index == iQueueStart)	// Yes, so overwrite

    71 			iQueueStart = (iQueueStart + 1) % QueueSize;

    72 		else

    73 			iQueueLength++;

    74 

    75 		}

    76 		

    77 	iQueue[index] = aInfo;		// default assignment operator used

    78 	}

    79 

    80 template<class TInfo, TInt QueueSize> TBool TNotificationQueue<TInfo, QueueSize>::Deque(TInfo& aInfo)

    81 /**

    82 De-queue the next InterfaceChange notification and return it

    83 

    84 @param aInfo returned notification info

    85 @return ETrue if a notification info was returned, EFalse otherwise (ie: queue was empty).

    86 */

    87 	{

    88 	if (!IsEmpty())

    89 		{

    90 		aInfo = iQueue[iQueueStart];	// default assignment operator used

    91 		iQueueLength--;

    92 		iQueueStart = (iQueueStart + 1) % QueueSize;

    93 		return ETrue;

    94 		}

    95 	else

    96 		return EFalse;

    97 	}

    98 

    99 template<class TInfo, TInt QueueSize>

   100 inline TInfo& TNotificationQueue<TInfo, QueueSize>::GetTheOldestElem()

   101 /**

   102 In the case if pointers are stored in the queue and it is full the oldest

   103 element can be deleted with this method to avoid memory leaking.

   104 */

   105     {    

   106     return iQueue[iQueueStart];

   107     }

   108