1 /*

     2 * Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description: 

    15 *

    16 */

    17 

    18 

    19 #include <stdlib.h>

    20 #include <assert.h>

    21 #include "LINKLIST.H"

    22 

    23 // LinkedListIterator

    24 

    25 LinkedListIterator::LinkedListIterator(ListItem* aItem):

    26 	iCurrentItem(aItem)

    27 	{}

    28 

    29 LinkedListIterator::LinkedListIterator(const LinkedList& aList):

    30 	iCurrentItem(aList.iHead)

    31 	{}

    32 

    33 ListItem* LinkedListIterator::operator() ()

    34 	{

    35 	ListItem* p = iCurrentItem;

    36 	if(iCurrentItem)

    37 		iCurrentItem = iCurrentItem->iNext;

    38 	return p;

    39 	}

    40 

    41 void LinkedListIterator::Reset()

    42 	{

    43 	iCurrentItem = iList->iHead;

    44 	}

    45 

    46 // ListItem

    47 

    48 ListItem::ListItem():

    49 	iNext(NULL)

    50 	{}

    51 

    52 ListItem::~ListItem()

    53 	{}

    54 

    55 // LinkedList

    56 

    57 LinkedList::LinkedList():

    58 	iHead(NULL),

    59 	iTail(NULL)

    60 	{}

    61 

    62 LinkedList::~LinkedList()

    63 	{}

    64 

    65 void LinkedList::AddToHead(ListItem* aNewItem)

    66 	{

    67 	if(iHead)

    68 		aNewItem->iNext = iHead;

    69 	else

    70 		iTail = aNewItem;

    71 	iHead = aNewItem;

    72 	}

    73 

    74 void LinkedList::AddToTail(ListItem* aNewItem)

    75 	{

    76 	if(iTail)

    77 		iTail->iNext = aNewItem;

    78 	else

    79 		iHead = aNewItem;

    80 	iTail = aNewItem;

    81 	}

    82 

    83 void LinkedList::DeleteAll()

    84 	{

    85 	ListItem* item = iHead; 

    86 	while(item)

    87 		{

    88 		ListItem* p = item;

    89 		item=item->iNext;

    90 		delete p;

    91 		}

    92 	iHead = NULL;

    93 	iTail = NULL;

    94 	}

    95 

    96 void LinkedList::AddAfter(ListItem* aExistingItem,ListItem* aNewItem)

    97 	{

    98 	if(aExistingItem==NULL)

    99 		AddToHead(aNewItem);

   100 	else if(aExistingItem == iTail)

   101 		AddToTail(aNewItem);

   102 	else

   103 		{

   104 		aNewItem->iNext = aExistingItem->iNext;

   105 		aExistingItem->iNext = aNewItem;

   106 		}

   107 	}

   108 

   109 ListItem* LinkedList::Previous(ListItem* aItem)

   110 	{

   111 	assert(aItem != NULL);

   112 	assert(iHead != NULL);

   113 	ListItem* p = iHead;

   114 	if(p == aItem)

   115 		return NULL;

   116 	while(p->iNext != aItem && p->iNext != NULL)

   117 		p = p->iNext;

   118 	assert(p->iNext == aItem);

   119 	return p;		

   120 	}

   121 

   122 void LinkedList::RemoveItem(ListItem* aItem)

   123 	{

   124 	assert(aItem != NULL);

   125 	assert(iHead != NULL);

   126 	// If item to remove is at head of list.	

   127 	if (iHead == aItem)

   128 		{

   129 		if(iTail == aItem)	// Item being removed is only item in list

   130 			iTail = NULL;	

   131 		iHead = aItem->iNext;

   132 		return;

   133 		}

   134     // Search through the list for the item.

   135 	ListItem* p = iHead;

   136 	while( p && (p->iNext!=aItem))

   137 		p = p->iNext;

   138 	assert(p!=NULL);

   139 	if (iTail == p->iNext)

   140 		iTail = p;

   141 	p->iNext = p->iNext->iNext;

   142 	}

   143 

   144 ListItem* LinkedList::TailItem()

   145 	{

   146 	return iTail;

   147 	}

   148 

   149 int LinkedList::IsEmpty()

   150 	{

   151 	return(iHead==NULL);

   152 	}