Modified source engine (2017) developed by valve and leaked in 2020. Not for commercial purporses
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//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose:
//
// $Header: $
// $NoKeywords: $
//=============================================================================//
#ifndef UTLRBTREE_H
#define UTLRBTREE_H
#include "tier1/utlmemory.h"
#include "tier1/utlfixedmemory.h"
#include "tier1/utlblockmemory.h"
#include "tier1/strtools.h"
//-----------------------------------------------------------------------------
// Tool to generate a default compare function for any type that implements
// operator<, including all simple types
//-----------------------------------------------------------------------------
template <typename T >
class CDefOps
{
public:
static bool LessFunc( const T &lhs, const T &rhs ) { return ( lhs < rhs ); }
};
#define DefLessFunc( type ) CDefOps< type >::LessFunc
template <typename T>
class CDefLess
{
public:
CDefLess() {}
CDefLess( int i ) {}
inline bool operator()( const T &lhs, const T &rhs ) const { return ( lhs < rhs ); }
inline bool operator!() const { return false; }
};
//-------------------------------------
inline bool StringLessThan( const char * const &lhs, const char * const &rhs) {
if ( !lhs ) return false;
if ( !rhs ) return true;
return ( V_strcmp( lhs, rhs) < 0 );
}
inline bool CaselessStringLessThan( const char * const &lhs, const char * const &rhs ) {
if ( !lhs ) return false;
if ( !rhs ) return true;
return ( V_stricmp( lhs, rhs) < 0 );
}
// Same as CaselessStringLessThan, but it ignores differences in / and \.
inline bool CaselessStringLessThanIgnoreSlashes( const char * const &lhs, const char * const &rhs )
{
const char *pa = lhs;
const char *pb = rhs;
while ( *pa && *pb )
{
char a = *pa;
char b = *pb;
// Check for dir slashes.
if ( a == '/' || a == '\\' )
{
if ( b != '/' && b != '\\' )
return ('/' < b);
}
else
{
if ( a >= 'a' && a <= 'z' )
a = 'A' + (a - 'a');
if ( b >= 'a' && b <= 'z' )
b = 'A' + (b - 'a');
if ( a > b )
return false;
else if ( a < b )
return true;
}
++pa;
++pb;
}
// Filenames also must be the same length.
if ( *pa != *pb )
{
// If pa shorter than pb then it's "less"
return ( !*pa );
}
return false;
}
//-------------------------------------
// inline these two templates to stop multiple definitions of the same code
template <> inline bool CDefOps<const char *>::LessFunc( const char * const &lhs, const char * const &rhs ) { return StringLessThan( lhs, rhs ); }
template <> inline bool CDefOps<char *>::LessFunc( char * const &lhs, char * const &rhs ) { return StringLessThan( lhs, rhs ); }
//-------------------------------------
template <typename RBTREE_T>
void SetDefLessFunc( RBTREE_T &RBTree )
{
RBTree.SetLessFunc( DefLessFunc( typename RBTREE_T::KeyType_t ) );
}
//-----------------------------------------------------------------------------
// A red-black binary search tree
//-----------------------------------------------------------------------------
template < class I >
struct UtlRBTreeLinks_t
{
I m_Left;
I m_Right;
I m_Parent;
I m_Tag;
};
template < class T, class I >
struct UtlRBTreeNode_t : public UtlRBTreeLinks_t< I >
{
T m_Data;
};
template < class T, class I = unsigned short, typename L = bool (*)( const T &, const T & ), class M = CUtlMemory< UtlRBTreeNode_t< T, I >, I > >
class CUtlRBTree
{
public:
typedef T KeyType_t;
typedef T ElemType_t;
typedef I IndexType_t;
// Less func typedef
// Returns true if the first parameter is "less" than the second
typedef L LessFunc_t;
// constructor, destructor
// Left at growSize = 0, the memory will first allocate 1 element and double in size
// at each increment.
// LessFunc_t is required, but may be set after the constructor using SetLessFunc() below
CUtlRBTree( int growSize = 0, int initSize = 0, const LessFunc_t &lessfunc = 0 );
CUtlRBTree( const LessFunc_t &lessfunc );
~CUtlRBTree( );
void EnsureCapacity( int num );
void CopyFrom( const CUtlRBTree<T, I, L, M> &other );
// gets particular elements
T& Element( I i );
T const &Element( I i ) const;
T& operator[]( I i );
T const &operator[]( I i ) const;
// Gets the root
I Root() const;
// Num elements
unsigned int Count() const;
// Max "size" of the vector
// it's not generally safe to iterate from index 0 to MaxElement()-1
// it IS safe to do so when using CUtlMemory as the allocator,
// but we should really remove patterns using this anyways, for safety and generality
I MaxElement() const;
// Gets the children
I Parent( I i ) const;
I LeftChild( I i ) const;
I RightChild( I i ) const;
// Tests if a node is a left or right child
bool IsLeftChild( I i ) const;
bool IsRightChild( I i ) const;
// Tests if root or leaf
bool IsRoot( I i ) const;
bool IsLeaf( I i ) const;
// Checks if a node is valid and in the tree
bool IsValidIndex( I i ) const;
// Checks if the tree as a whole is valid
bool IsValid() const;
// Invalid index
static I InvalidIndex();
// returns the tree depth (not a very fast operation)
int Depth( I node ) const;
int Depth() const;
// Sets the less func
void SetLessFunc( const LessFunc_t &func );
// Allocation method
I NewNode();
// Insert method (inserts in order)
I Insert( T const &insert );
void Insert( const T *pArray, int nItems );
I InsertIfNotFound( T const &insert );
// Find method
I Find( T const &search ) const;
// Remove methods
void RemoveAt( I i );
bool Remove( T const &remove );
void RemoveAll( );
void Purge();
bool HasElement( T const &search ) const { return Find( search ) != InvalidIndex(); }
// Allocation, deletion
void FreeNode( I i );
// Iteration
I FirstInorder() const;
I NextInorder( I i ) const;
I PrevInorder( I i ) const;
I LastInorder() const;
I FirstPreorder() const;
I NextPreorder( I i ) const;
I PrevPreorder( I i ) const;
I LastPreorder( ) const;
I FirstPostorder() const;
I NextPostorder( I i ) const;
// If you change the search key, this can be used to reinsert the
// element into the tree.
void Reinsert( I elem );
// swap in place
void Swap( CUtlRBTree< T, I, L > &that );
private:
// Can't copy the tree this way!
CUtlRBTree<T, I, L, M>& operator=( const CUtlRBTree<T, I, L, M> &other );
protected:
enum NodeColor_t
{
RED = 0,
BLACK
};
typedef UtlRBTreeNode_t< T, I > Node_t;
typedef UtlRBTreeLinks_t< I > Links_t;
// Sets the children
void SetParent( I i, I parent );
void SetLeftChild( I i, I child );
void SetRightChild( I i, I child );
void LinkToParent( I i, I parent, bool isLeft );
// Gets at the links
Links_t const &Links( I i ) const;
Links_t &Links( I i );
// Checks if a link is red or black
bool IsRed( I i ) const;
bool IsBlack( I i ) const;
// Sets/gets node color
NodeColor_t Color( I i ) const;
void SetColor( I i, NodeColor_t c );
// operations required to preserve tree balance
void RotateLeft(I i);
void RotateRight(I i);
void InsertRebalance(I i);
void RemoveRebalance(I i);
// Insertion, removal
I InsertAt( I parent, bool leftchild );
// copy constructors not allowed
CUtlRBTree( CUtlRBTree<T, I, L, M> const &tree );
// Inserts a node into the tree, doesn't copy the data in.
void FindInsertionPosition( T const &insert, I &parent, bool &leftchild );
// Remove and add back an element in the tree.
void Unlink( I elem );
void Link( I elem );
// Used for sorting.
LessFunc_t m_LessFunc;
M m_Elements;
I m_Root;
I m_NumElements;
I m_FirstFree;
typename M::Iterator_t m_LastAlloc; // the last index allocated
Node_t* m_pElements;
FORCEINLINE M const &Elements( void ) const
{
return m_Elements;
}
void ResetDbgInfo()
{
m_pElements = (Node_t*)m_Elements.Base();
}
};
// this is kind of ugly, but until C++ gets templatized typedefs in C++0x, it's our only choice
template < class T, class I = int, typename L = bool (*)( const T &, const T & ) >
class CUtlFixedRBTree : public CUtlRBTree< T, I, L, CUtlFixedMemory< UtlRBTreeNode_t< T, I > > >
{
public:
typedef L LessFunc_t;
CUtlFixedRBTree( int growSize = 0, int initSize = 0, const LessFunc_t &lessfunc = 0 )
: CUtlRBTree< T, I, L, CUtlFixedMemory< UtlRBTreeNode_t< T, I > > >( growSize, initSize, lessfunc ) {}
CUtlFixedRBTree( const LessFunc_t &lessfunc )
: CUtlRBTree< T, I, L, CUtlFixedMemory< UtlRBTreeNode_t< T, I > > >( lessfunc ) {}
typedef CUtlRBTree< T, I, L, CUtlFixedMemory< UtlRBTreeNode_t< T, I > > > BaseClass;
bool IsValidIndex( I i ) const
{
if ( !BaseClass::Elements().IsIdxValid( i ) )
return false;
#ifdef _DEBUG // it's safe to skip this here, since the only way to get indices after m_LastAlloc is to use MaxElement()
if ( BaseClass::Elements().IsIdxAfter( i, this->m_LastAlloc ) )
{
Assert( 0 );
return false; // don't read values that have been allocated, but not constructed
}
#endif
return LeftChild(i) != i;
}
protected:
void ResetDbgInfo() {}
private:
// this doesn't make sense for fixed rbtrees, since there's no useful max pointer, and the index space isn't contiguous anyways
I MaxElement() const;
};
// this is kind of ugly, but until C++ gets templatized typedefs in C++0x, it's our only choice
template < class T, class I = unsigned short, typename L = bool (*)( const T &, const T & ) >
class CUtlBlockRBTree : public CUtlRBTree< T, I, L, CUtlBlockMemory< UtlRBTreeNode_t< T, I >, I > >
{
public:
typedef L LessFunc_t;
CUtlBlockRBTree( int growSize = 0, int initSize = 0, const LessFunc_t &lessfunc = 0 )
: CUtlRBTree< T, I, L, CUtlBlockMemory< UtlRBTreeNode_t< T, I >, I > >( growSize, initSize, lessfunc ) {}
CUtlBlockRBTree( const LessFunc_t &lessfunc )
: CUtlRBTree< T, I, L, CUtlBlockMemory< UtlRBTreeNode_t< T, I >, I > >( lessfunc ) {}
protected:
void ResetDbgInfo() {}
};
//-----------------------------------------------------------------------------
// constructor, destructor
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline CUtlRBTree<T, I, L, M>::CUtlRBTree( int growSize, int initSize, const LessFunc_t &lessfunc ) :
m_Elements( growSize, initSize ),
m_LessFunc( lessfunc ),
m_Root( InvalidIndex() ),
m_NumElements( 0 ),
m_FirstFree( InvalidIndex() ),
m_LastAlloc( m_Elements.InvalidIterator() )
{
ResetDbgInfo();
}
template < class T, class I, typename L, class M >
inline CUtlRBTree<T, I, L, M>::CUtlRBTree( const LessFunc_t &lessfunc ) :
m_Elements( 0, 0 ),
m_LessFunc( lessfunc ),
m_Root( InvalidIndex() ),
m_NumElements( 0 ),
m_FirstFree( InvalidIndex() ),
m_LastAlloc( m_Elements.InvalidIterator() )
{
ResetDbgInfo();
}
template < class T, class I, typename L, class M >
inline CUtlRBTree<T, I, L, M>::~CUtlRBTree()
{
Purge();
}
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::EnsureCapacity( int num )
{
m_Elements.EnsureCapacity( num );
}
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::CopyFrom( const CUtlRBTree<T, I, L, M> &other )
{
Purge();
m_Elements.EnsureCapacity( other.m_Elements.Count() );
memcpy( m_Elements.Base(), other.m_Elements.Base(), other.m_Elements.Count() * sizeof( T ) );
m_LessFunc = other.m_LessFunc;
m_Root = other.m_Root;
m_NumElements = other.m_NumElements;
m_FirstFree = other.m_FirstFree;
m_LastAlloc = other.m_LastAlloc;
ResetDbgInfo();
}
//-----------------------------------------------------------------------------
// gets particular elements
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline T &CUtlRBTree<T, I, L, M>::Element( I i )
{
return m_Elements[i].m_Data;
}
template < class T, class I, typename L, class M >
inline T const &CUtlRBTree<T, I, L, M>::Element( I i ) const
{
return m_Elements[i].m_Data;
}
template < class T, class I, typename L, class M >
inline T &CUtlRBTree<T, I, L, M>::operator[]( I i )
{
return Element(i);
}
template < class T, class I, typename L, class M >
inline T const &CUtlRBTree<T, I, L, M>::operator[]( I i ) const
{
return Element(i);
}
//-----------------------------------------------------------------------------
//
// various accessors
//
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// Gets the root
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::Root() const
{
return m_Root;
}
//-----------------------------------------------------------------------------
// Num elements
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline unsigned int CUtlRBTree<T, I, L, M>::Count() const
{
return (unsigned int)m_NumElements;
}
//-----------------------------------------------------------------------------
// Max "size" of the vector
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::MaxElement() const
{
return ( I )m_Elements.NumAllocated();
}
//-----------------------------------------------------------------------------
// Gets the children
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::Parent( I i ) const
{
return Links(i).m_Parent;
}
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::LeftChild( I i ) const
{
return Links(i).m_Left;
}
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::RightChild( I i ) const
{
return Links(i).m_Right;
}
//-----------------------------------------------------------------------------
// Tests if a node is a left or right child
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsLeftChild( I i ) const
{
return LeftChild(Parent(i)) == i;
}
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsRightChild( I i ) const
{
return RightChild(Parent(i)) == i;
}
//-----------------------------------------------------------------------------
// Tests if root or leaf
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsRoot( I i ) const
{
return i == m_Root;
}
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsLeaf( I i ) const
{
return (LeftChild(i) == InvalidIndex()) && (RightChild(i) == InvalidIndex());
}
//-----------------------------------------------------------------------------
// Checks if a node is valid and in the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsValidIndex( I i ) const
{
if ( !m_Elements.IsIdxValid( i ) )
return false;
if ( m_LastAlloc == m_Elements.InvalidIndex() || m_Elements.IsIdxAfter( i, m_LastAlloc ) )
return false; // don't read values that have been allocated, but not constructed
return LeftChild(i) != i;
}
//-----------------------------------------------------------------------------
// Invalid index
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline I CUtlRBTree<T, I, L, M>::InvalidIndex()
{
return ( I )M::InvalidIndex();
}
//-----------------------------------------------------------------------------
// returns the tree depth (not a very fast operation)
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline int CUtlRBTree<T, I, L, M>::Depth() const
{
return Depth(Root());
}
//-----------------------------------------------------------------------------
// Sets the children
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::SetParent( I i, I parent )
{
Links(i).m_Parent = parent;
}
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::SetLeftChild( I i, I child )
{
Links(i).m_Left = child;
}
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::SetRightChild( I i, I child )
{
Links(i).m_Right = child;
}
//-----------------------------------------------------------------------------
// Gets at the links
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline typename CUtlRBTree<T, I, L, M>::Links_t const &CUtlRBTree<T, I, L, M>::Links( I i ) const
{
// Sentinel node, makes life easier
static Links_t s_Sentinel =
{
InvalidIndex(), InvalidIndex(), InvalidIndex(), CUtlRBTree<T, I, L, M>::BLACK
};
return (i != InvalidIndex()) ? *(Links_t*)&m_Elements[i] : *(Links_t*)&s_Sentinel;
}
template < class T, class I, typename L, class M >
inline typename CUtlRBTree<T, I, L, M>::Links_t &CUtlRBTree<T, I, L, M>::Links( I i )
{
Assert(i != InvalidIndex());
return *(Links_t *)&m_Elements[i];
}
//-----------------------------------------------------------------------------
// Checks if a link is red or black
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsRed( I i ) const
{
return (Links(i).m_Tag == RED);
}
template < class T, class I, typename L, class M >
inline bool CUtlRBTree<T, I, L, M>::IsBlack( I i ) const
{
return (Links(i).m_Tag == BLACK);
}
//-----------------------------------------------------------------------------
// Sets/gets node color
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
inline typename CUtlRBTree<T, I, L, M>::NodeColor_t CUtlRBTree<T, I, L, M>::Color( I i ) const
{
return (NodeColor_t)Links(i).m_Tag;
}
template < class T, class I, typename L, class M >
inline void CUtlRBTree<T, I, L, M>::SetColor( I i, typename CUtlRBTree<T, I, L, M>::NodeColor_t c )
{
Links(i).m_Tag = (I)c;
}
//-----------------------------------------------------------------------------
// Allocates/ deallocates nodes
//-----------------------------------------------------------------------------
#ifdef _WIN32
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#pragma warning(push)
#pragma warning(disable:4389) // '==' : signed/unsigned mismatch
#endif
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template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::NewNode()
{
I elem;
// Nothing in the free list; add.
if ( m_FirstFree == InvalidIndex() )
{
Assert( m_Elements.IsValidIterator( m_LastAlloc ) || m_NumElements == 0 );
typename M::Iterator_t it = m_Elements.IsValidIterator( m_LastAlloc ) ? m_Elements.Next( m_LastAlloc ) : m_Elements.First();
if ( !m_Elements.IsValidIterator( it ) )
{
MEM_ALLOC_CREDIT_CLASS();
m_Elements.Grow();
it = m_Elements.IsValidIterator( m_LastAlloc ) ? m_Elements.Next( m_LastAlloc ) : m_Elements.First();
Assert( m_Elements.IsValidIterator( it ) );
if ( !m_Elements.IsValidIterator( it ) )
{
Error( "CUtlRBTree overflow!\n" );
}
}
m_LastAlloc = it;
elem = m_Elements.GetIndex( m_LastAlloc );
Assert( m_Elements.IsValidIterator( m_LastAlloc ) );
}
else
{
elem = m_FirstFree;
m_FirstFree = Links( m_FirstFree ).m_Right;
}
#ifdef _DEBUG
// reset links to invalid....
Links_t &node = Links( elem );
node.m_Left = node.m_Right = node.m_Parent = InvalidIndex();
#endif
Construct( &Element( elem ) );
ResetDbgInfo();
return elem;
}
#ifdef _WIN32
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#pragma warning(pop)
#endif
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template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::FreeNode( I i )
{
Assert( IsValidIndex(i) && (i != InvalidIndex()) );
Destruct( &Element(i) );
SetLeftChild( i, i ); // indicates it's in not in the tree
SetRightChild( i, m_FirstFree );
m_FirstFree = i;
}
//-----------------------------------------------------------------------------
// Rotates node i to the left
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::RotateLeft(I elem)
{
I rightchild = RightChild(elem);
SetRightChild( elem, LeftChild(rightchild) );
if (LeftChild(rightchild) != InvalidIndex())
SetParent( LeftChild(rightchild), elem );
if (rightchild != InvalidIndex())
SetParent( rightchild, Parent(elem) );
if (!IsRoot(elem))
{
if (IsLeftChild(elem))
SetLeftChild( Parent(elem), rightchild );
else
SetRightChild( Parent(elem), rightchild );
}
else
m_Root = rightchild;
SetLeftChild( rightchild, elem );
if (elem != InvalidIndex())
SetParent( elem, rightchild );
}
//-----------------------------------------------------------------------------
// Rotates node i to the right
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::RotateRight(I elem)
{
I leftchild = LeftChild(elem);
SetLeftChild( elem, RightChild(leftchild) );
if (RightChild(leftchild) != InvalidIndex())
SetParent( RightChild(leftchild), elem );
if (leftchild != InvalidIndex())
SetParent( leftchild, Parent(elem) );
if (!IsRoot(elem))
{
if (IsRightChild(elem))
SetRightChild( Parent(elem), leftchild );
else
SetLeftChild( Parent(elem), leftchild );
}
else
m_Root = leftchild;
SetRightChild( leftchild, elem );
if (elem != InvalidIndex())
SetParent( elem, leftchild );
}
//-----------------------------------------------------------------------------
// Rebalances the tree after an insertion
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::InsertRebalance(I elem)
{
while ( !IsRoot(elem) && (Color(Parent(elem)) == RED) )
{
I parent = Parent(elem);
I grandparent = Parent(parent);
/* we have a violation */
if (IsLeftChild(parent))
{
I uncle = RightChild(grandparent);
if (IsRed(uncle))
{
/* uncle is RED */
SetColor(parent, BLACK);
SetColor(uncle, BLACK);
SetColor(grandparent, RED);
elem = grandparent;
}
else
{
/* uncle is BLACK */
if (IsRightChild(elem))
{
/* make x a left child, will change parent and grandparent */
elem = parent;
RotateLeft(elem);
parent = Parent(elem);
grandparent = Parent(parent);
}
/* recolor and rotate */
SetColor(parent, BLACK);
SetColor(grandparent, RED);
RotateRight(grandparent);
}
}
else
{
/* mirror image of above code */
I uncle = LeftChild(grandparent);
if (IsRed(uncle))
{
/* uncle is RED */
SetColor(parent, BLACK);
SetColor(uncle, BLACK);
SetColor(grandparent, RED);
elem = grandparent;
}
else
{
/* uncle is BLACK */
if (IsLeftChild(elem))
{
/* make x a right child, will change parent and grandparent */
elem = parent;
RotateRight(parent);
parent = Parent(elem);
grandparent = Parent(parent);
}
/* recolor and rotate */
SetColor(parent, BLACK);
SetColor(grandparent, RED);
RotateLeft(grandparent);
}
}
}
SetColor( m_Root, BLACK );
}
//-----------------------------------------------------------------------------
// Insert a node into the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::InsertAt( I parent, bool leftchild )
{
I i = NewNode();
LinkToParent( i, parent, leftchild );
++m_NumElements;
Assert(IsValid());
return i;
}
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::LinkToParent( I i, I parent, bool isLeft )
{
Links_t &elem = Links(i);
elem.m_Parent = parent;
elem.m_Left = elem.m_Right = InvalidIndex();
elem.m_Tag = RED;
/* insert node in tree */
if (parent != InvalidIndex())
{
if (isLeft)
Links(parent).m_Left = i;
else
Links(parent).m_Right = i;
}
else
{
m_Root = i;
}
InsertRebalance(i);
}
//-----------------------------------------------------------------------------
// Rebalance the tree after a deletion
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::RemoveRebalance(I elem)
{
while (elem != m_Root && IsBlack(elem))
{
I parent = Parent(elem);
// If elem is the left child of the parent
if (elem == LeftChild(parent))
{
// Get our sibling
I sibling = RightChild(parent);
if (IsRed(sibling))
{
SetColor(sibling, BLACK);
SetColor(parent, RED);
RotateLeft(parent);
// We may have a new parent now
parent = Parent(elem);
sibling = RightChild(parent);
}
if ( (IsBlack(LeftChild(sibling))) && (IsBlack(RightChild(sibling))) )
{
if (sibling != InvalidIndex())
SetColor(sibling, RED);
elem = parent;
}
else
{
if (IsBlack(RightChild(sibling)))
{
SetColor(LeftChild(sibling), BLACK);
SetColor(sibling, RED);
RotateRight(sibling);
// rotation may have changed this
parent = Parent(elem);
sibling = RightChild(parent);
}
SetColor( sibling, Color(parent) );
SetColor( parent, BLACK );
SetColor( RightChild(sibling), BLACK );
RotateLeft( parent );
elem = m_Root;
}
}
else
{
// Elem is the right child of the parent
I sibling = LeftChild(parent);
if (IsRed(sibling))
{
SetColor(sibling, BLACK);
SetColor(parent, RED);
RotateRight(parent);
// We may have a new parent now
parent = Parent(elem);
sibling = LeftChild(parent);
}
if ( (IsBlack(RightChild(sibling))) && (IsBlack(LeftChild(sibling))) )
{
if (sibling != InvalidIndex())
SetColor( sibling, RED );
elem = parent;
}
else
{
if (IsBlack(LeftChild(sibling)))
{
SetColor( RightChild(sibling), BLACK );
SetColor( sibling, RED );
RotateLeft( sibling );
// rotation may have changed this
parent = Parent(elem);
sibling = LeftChild(parent);
}
SetColor( sibling, Color(parent) );
SetColor( parent, BLACK );
SetColor( LeftChild(sibling), BLACK );
RotateRight( parent );
elem = m_Root;
}
}
}
SetColor( elem, BLACK );
}
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Unlink( I elem )
{
if ( elem != InvalidIndex() )
{
I x, y;
if ((LeftChild(elem) == InvalidIndex()) ||
(RightChild(elem) == InvalidIndex()))
{
/* y has a NIL node as a child */
y = elem;
}
else
{
/* find tree successor with a NIL node as a child */
y = RightChild(elem);
while (LeftChild(y) != InvalidIndex())
y = LeftChild(y);
}
/* x is y's only child */
if (LeftChild(y) != InvalidIndex())
x = LeftChild(y);
else
x = RightChild(y);
/* remove y from the parent chain */
if (x != InvalidIndex())
SetParent( x, Parent(y) );
if (!IsRoot(y))
{
if (IsLeftChild(y))
SetLeftChild( Parent(y), x );
else
SetRightChild( Parent(y), x );
}
else
m_Root = x;
// need to store this off now, we'll be resetting y's color
NodeColor_t ycolor = Color(y);
if (y != elem)
{
// Standard implementations copy the data around, we cannot here.
// Hook in y to link to the same stuff elem used to.
SetParent( y, Parent(elem) );
SetRightChild( y, RightChild(elem) );
SetLeftChild( y, LeftChild(elem) );
if (!IsRoot(elem))
if (IsLeftChild(elem))
SetLeftChild( Parent(elem), y );
else
SetRightChild( Parent(elem), y );
else
m_Root = y;
if (LeftChild(y) != InvalidIndex())
SetParent( LeftChild(y), y );
if (RightChild(y) != InvalidIndex())
SetParent( RightChild(y), y );
SetColor( y, Color(elem) );
}
if ((x != InvalidIndex()) && (ycolor == BLACK))
RemoveRebalance(x);
}
}
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Link( I elem )
{
if ( elem != InvalidIndex() )
{
I parent;
bool leftchild;
FindInsertionPosition( Element( elem ), parent, leftchild );
LinkToParent( elem, parent, leftchild );
Assert(IsValid());
}
}
//-----------------------------------------------------------------------------
// Delete a node from the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::RemoveAt(I elem)
{
if ( elem != InvalidIndex() )
{
Unlink( elem );
FreeNode(elem);
--m_NumElements;
Assert(IsValid());
}
}
//-----------------------------------------------------------------------------
// remove a node in the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M > bool CUtlRBTree<T, I, L, M>::Remove( T const &search )
{
I node = Find( search );
if (node != InvalidIndex())
{
RemoveAt(node);
return true;
}
return false;
}
//-----------------------------------------------------------------------------
// Removes all nodes from the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::RemoveAll()
{
// Have to do some convoluted stuff to invoke the destructor on all
// valid elements for the multilist case (since we don't have all elements
// connected to each other in a list).
if ( m_LastAlloc == m_Elements.InvalidIterator() )
{
Assert( m_Root == InvalidIndex() );
Assert( m_FirstFree == InvalidIndex() );
Assert( m_NumElements == 0 );
return;
}
for ( typename M::Iterator_t it = m_Elements.First(); it != m_Elements.InvalidIterator(); it = m_Elements.Next( it ) )
{
I i = m_Elements.GetIndex( it );
if ( IsValidIndex( i ) ) // skip elements in the free list
{
Destruct( &Element( i ) );
SetRightChild( i, m_FirstFree );
SetLeftChild( i, i );
m_FirstFree = i;
}
if ( it == m_LastAlloc )
break; // don't destruct elements that haven't ever been constucted
}
// Clear everything else out
m_Root = InvalidIndex();
// Technically, this iterator could become invalid. It will not, because it's
// always the same iterator. If we don't clear this here, the state of this
// container will be invalid after we start inserting elements again.
m_LastAlloc = m_Elements.InvalidIterator();
m_FirstFree = InvalidIndex();
m_NumElements = 0;
Assert( IsValid() );
}
//-----------------------------------------------------------------------------
// Removes all nodes from the tree and purges memory
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Purge()
{
RemoveAll();
m_Elements.Purge();
}
//-----------------------------------------------------------------------------
// iteration
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::FirstInorder() const
{
I i = m_Root;
while (LeftChild(i) != InvalidIndex())
i = LeftChild(i);
return i;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::NextInorder( I i ) const
{
// Don't go into an infinite loop if it's a bad index
Assert(IsValidIndex(i));
if ( !IsValidIndex(i) )
return InvalidIndex();
if (RightChild(i) != InvalidIndex())
{
i = RightChild(i);
while (LeftChild(i) != InvalidIndex())
i = LeftChild(i);
return i;
}
I parent = Parent(i);
while (IsRightChild(i))
{
i = parent;
if (i == InvalidIndex()) break;
parent = Parent(i);
}
return parent;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::PrevInorder( I i ) const
{
// Don't go into an infinite loop if it's a bad index
Assert(IsValidIndex(i));
if ( !IsValidIndex(i) )
return InvalidIndex();
if (LeftChild(i) != InvalidIndex())
{
i = LeftChild(i);
while (RightChild(i) != InvalidIndex())
i = RightChild(i);
return i;
}
I parent = Parent(i);
while (IsLeftChild(i))
{
i = parent;
if (i == InvalidIndex()) break;
parent = Parent(i);
}
return parent;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::LastInorder() const
{
I i = m_Root;
while (RightChild(i) != InvalidIndex())
i = RightChild(i);
return i;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::FirstPreorder() const
{
return m_Root;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::NextPreorder( I i ) const
{
if (LeftChild(i) != InvalidIndex())
return LeftChild(i);
if (RightChild(i) != InvalidIndex())
return RightChild(i);
I parent = Parent(i);
while( parent != InvalidIndex())
{
if (IsLeftChild(i) && (RightChild(parent) != InvalidIndex()))
return RightChild(parent);
i = parent;
parent = Parent(parent);
}
return InvalidIndex();
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::PrevPreorder( I i ) const
{
Assert(0); // not implemented yet
return InvalidIndex();
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::LastPreorder() const
{
I i = m_Root;
while (1)
{
while (RightChild(i) != InvalidIndex())
i = RightChild(i);
if (LeftChild(i) != InvalidIndex())
i = LeftChild(i);
else
break;
}
return i;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::FirstPostorder() const
{
I i = m_Root;
while (!IsLeaf(i))
{
if (LeftChild(i))
i = LeftChild(i);
else
i = RightChild(i);
}
return i;
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::NextPostorder( I i ) const
{
I parent = Parent(i);
if (parent == InvalidIndex())
return InvalidIndex();
if (IsRightChild(i))
return parent;
if (RightChild(parent) == InvalidIndex())
return parent;
i = RightChild(parent);
while (!IsLeaf(i))
{
if (LeftChild(i))
i = LeftChild(i);
else
i = RightChild(i);
}
return i;
}
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Reinsert( I elem )
{
Unlink( elem );
Link( elem );
}
//-----------------------------------------------------------------------------
// returns the tree depth (not a very fast operation)
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
int CUtlRBTree<T, I, L, M>::Depth( I node ) const
{
if (node == InvalidIndex())
return 0;
int depthright = Depth( RightChild(node) );
int depthleft = Depth( LeftChild(node) );
return Max(depthright, depthleft) + 1;
}
//#define UTLTREE_PARANOID
//-----------------------------------------------------------------------------
// Makes sure the tree is valid after every operation
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
bool CUtlRBTree<T, I, L, M>::IsValid() const
{
if ( !Count() )
return true;
if ( m_LastAlloc == m_Elements.InvalidIterator() )
return false;
if ( !m_Elements.IsIdxValid( Root() ) )
return false;
if ( Parent( Root() ) != InvalidIndex() )
return false;
#ifdef UTLTREE_PARANOID
// First check to see that mNumEntries matches reality.
// count items on the free list
int numFree = 0;
for ( int i = m_FirstFree; i != InvalidIndex(); i = RightChild( i ) )
{
++numFree;
if ( !m_Elements.IsIdxValid( i ) )
return false;
}
// iterate over all elements, looking for validity
// based on the self pointers
int nElements = 0;
int numFree2 = 0;
for ( M::Iterator_t it = m_Elements.First(); it != m_Elements.InvalidIterator(); it = m_Elements.Next( it ) )
{
I i = m_Elements.GetIndex( it );
if ( !IsValidIndex( i ) )
{
++numFree2;
}
else
{
++nElements;
int right = RightChild( i );
int left = LeftChild( i );
if ( ( right == left ) && ( right != InvalidIndex() ) )
return false;
if ( right != InvalidIndex() )
{
if ( !IsValidIndex( right ) )
return false;
if ( Parent( right ) != i )
return false;
if ( IsRed( i ) && IsRed( right ) )
return false;
}
if ( left != InvalidIndex() )
{
if ( !IsValidIndex( left ) )
return false;
if ( Parent( left ) != i )
return false;
if ( IsRed( i ) && IsRed( left ) )
return false;
}
}
if ( it == m_LastAlloc )
break;
}
if ( numFree2 != numFree )
return false;
if ( nElements != m_NumElements )
return false;
#endif // UTLTREE_PARANOID
return true;
}
//-----------------------------------------------------------------------------
// Sets the less func
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::SetLessFunc( const typename CUtlRBTree<T, I, L, M>::LessFunc_t &func )
{
if (!m_LessFunc)
{
m_LessFunc = func;
}
else if ( Count() > 0 )
{
// need to re-sort the tree here....
Assert(0);
}
}
//-----------------------------------------------------------------------------
// inserts a node into the tree
//-----------------------------------------------------------------------------
// Inserts a node into the tree, doesn't copy the data in.
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::FindInsertionPosition( T const &insert, I &parent, bool &leftchild )
{
Assert( m_LessFunc );
/* find where node belongs */
I current = m_Root;
parent = InvalidIndex();
leftchild = false;
while (current != InvalidIndex())
{
parent = current;
if (m_LessFunc( insert, Element(current) ))
{
leftchild = true; current = LeftChild(current);
}
else
{
leftchild = false; current = RightChild(current);
}
}
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::Insert( T const &insert )
{
// use copy constructor to copy it in
I parent;
bool leftchild;
FindInsertionPosition( insert, parent, leftchild );
I newNode = InsertAt( parent, leftchild );
CopyConstruct( &Element( newNode ), insert );
return newNode;
}
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Insert( const T *pArray, int nItems )
{
while ( nItems-- )
{
Insert( *pArray++ );
}
}
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::InsertIfNotFound( T const &insert )
{
// use copy constructor to copy it in
I parent;
bool leftchild;
I current = m_Root;
parent = InvalidIndex();
leftchild = false;
while (current != InvalidIndex())
{
parent = current;
if (m_LessFunc( insert, Element(current) ))
{
leftchild = true; current = LeftChild(current);
}
else if (m_LessFunc( Element(current), insert ))
{
leftchild = false; current = RightChild(current);
}
else
// Match found, no insertion
return InvalidIndex();
}
I newNode = InsertAt( parent, leftchild );
CopyConstruct( &Element( newNode ), insert );
return newNode;
}
//-----------------------------------------------------------------------------
// finds a node in the tree
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
I CUtlRBTree<T, I, L, M>::Find( T const &search ) const
{
Assert( m_LessFunc );
I current = m_Root;
while (current != InvalidIndex())
{
if (m_LessFunc( search, Element(current) ))
current = LeftChild(current);
else if (m_LessFunc( Element(current), search ))
current = RightChild(current);
else
break;
}
return current;
}
//-----------------------------------------------------------------------------
// swap in place
//-----------------------------------------------------------------------------
template < class T, class I, typename L, class M >
void CUtlRBTree<T, I, L, M>::Swap( CUtlRBTree< T, I, L > &that )
{
m_Elements.Swap( that.m_Elements );
V_swap( m_LessFunc, that.m_LessFunc );
V_swap( m_Root, that.m_Root );
V_swap( m_NumElements, that.m_NumElements );
V_swap( m_FirstFree, that.m_FirstFree );
V_swap( m_pElements, that.m_pElements );
V_swap( m_LastAlloc, that.m_LastAlloc );
Assert( IsValid() );
Assert( m_Elements.IsValidIterator( m_LastAlloc ) || ( m_NumElements == 0 && m_FirstFree == InvalidIndex() ) );
}
#endif // UTLRBTREE_H