/*
===========================================================================
Doom 3 BFG Edition GPL Source Code
Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code").
Doom 3 BFG Edition Source Code is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Doom 3 BFG Edition Source Code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Doom 3 BFG Edition Source Code. If not, see .
In addition, the Doom 3 BFG Edition Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 BFG Edition Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#ifndef __LINKLIST_H__
#define __LINKLIST_H__
/*
==============================================================================
idLinkList
Circular linked list template
==============================================================================
*/
template< class type >
class idLinkList
{
public:
idLinkList();
~idLinkList();
bool IsListEmpty() const;
bool InList() const;
int Num() const;
void Clear();
void InsertBefore( idLinkList& node );
void InsertAfter( idLinkList& node );
void AddToEnd( idLinkList& node );
void AddToFront( idLinkList& node );
void Remove();
type* Next() const;
type* Prev() const;
type* Owner() const;
void SetOwner( type* object );
idLinkList* ListHead() const;
idLinkList* NextNode() const;
idLinkList* PrevNode() const;
private:
idLinkList* head;
idLinkList* next;
idLinkList* prev;
type* owner;
};
/*
================
idLinkList::idLinkList
Node is initialized to be the head of an empty list
================
*/
template< class type >
idLinkList::idLinkList()
{
owner = NULL;
head = this;
next = this;
prev = this;
}
/*
================
idLinkList::~idLinkList
Removes the node from the list, or if it's the head of a list, removes
all the nodes from the list.
================
*/
template< class type >
idLinkList::~idLinkList()
{
Clear();
}
/*
================
idLinkList::IsListEmpty
Returns true if the list is empty.
================
*/
template< class type >
bool idLinkList::IsListEmpty() const
{
return head->next == head;
}
/*
================
idLinkList::InList
Returns true if the node is in a list. If called on the head of a list, will always return false.
================
*/
template< class type >
bool idLinkList::InList() const
{
return head != this;
}
/*
================
idLinkList::Num
Returns the number of nodes in the list.
================
*/
template< class type >
int idLinkList::Num() const
{
idLinkList* node;
int num;
num = 0;
for( node = head->next; node != head; node = node->next )
{
num++;
}
return num;
}
/*
================
idLinkList::Clear
If node is the head of the list, clears the list. Otherwise it just removes the node from the list.
================
*/
template< class type >
void idLinkList::Clear()
{
if( head == this )
{
while( next != this )
{
next->Remove();
}
}
else
{
Remove();
}
}
/*
================
idLinkList::Remove
Removes node from list
================
*/
template< class type >
void idLinkList::Remove()
{
prev->next = next;
next->prev = prev;
next = this;
prev = this;
head = this;
}
/*
================
idLinkList::InsertBefore
Places the node before the existing node in the list. If the existing node is the head,
then the new node is placed at the end of the list.
================
*/
template< class type >
void idLinkList::InsertBefore( idLinkList& node )
{
Remove();
next = &node;
prev = node.prev;
node.prev = this;
prev->next = this;
head = node.head;
}
/*
================
idLinkList::InsertAfter
Places the node after the existing node in the list. If the existing node is the head,
then the new node is placed at the beginning of the list.
================
*/
template< class type >
void idLinkList::InsertAfter( idLinkList& node )
{
Remove();
prev = &node;
next = node.next;
node.next = this;
next->prev = this;
head = node.head;
}
/*
================
idLinkList::AddToEnd
Adds node at the end of the list
================
*/
template< class type >
void idLinkList::AddToEnd( idLinkList& node )
{
InsertBefore( *node.head );
}
/*
================
idLinkList::AddToFront
Adds node at the beginning of the list
================
*/
template< class type >
void idLinkList::AddToFront( idLinkList& node )
{
InsertAfter( *node.head );
}
/*
================
idLinkList::ListHead
Returns the head of the list. If the node isn't in a list, it returns
a pointer to itself.
================
*/
template< class type >
idLinkList* idLinkList::ListHead() const
{
return head;
}
/*
================
idLinkList::Next
Returns the next object in the list, or NULL if at the end.
================
*/
template< class type >
type* idLinkList::Next() const
{
if( !next || ( next == head ) )
{
return NULL;
}
return next->owner;
}
/*
================
idLinkList::Prev
Returns the previous object in the list, or NULL if at the beginning.
================
*/
template< class type >
type* idLinkList::Prev() const
{
if( !prev || ( prev == head ) )
{
return NULL;
}
return prev->owner;
}
/*
================
idLinkList::NextNode
Returns the next node in the list, or NULL if at the end.
================
*/
template< class type >
idLinkList* idLinkList::NextNode() const
{
if( next == head )
{
return NULL;
}
return next;
}
/*
================
idLinkList::PrevNode
Returns the previous node in the list, or NULL if at the beginning.
================
*/
template< class type >
idLinkList* idLinkList::PrevNode() const
{
if( prev == head )
{
return NULL;
}
return prev;
}
/*
================
idLinkList::Owner
Gets the object that is associated with this node.
================
*/
template< class type >
type* idLinkList::Owner() const
{
return owner;
}
/*
================
idLinkList::SetOwner
Sets the object that this node is associated with.
================
*/
template< class type >
void idLinkList::SetOwner( type* object )
{
owner = object;
}
#endif /* !__LINKLIST_H__ */