Qt Toolkit - qmap.h include file

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# qmap.h

This is the verbatim text of the qmap.h include file. It is provided only for illustration; the copyright remains with Trolltech.

    /****************************************************************************
    ** $Id: qt/src/tools/qmap.h   2.3.0   edited 2001-01-26 $
    **
    ** Definition of QMap class
    **
    ** Created : 990406
    **
    ** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
    **
    ** This file is part of the tools module of the Qt GUI Toolkit.
    **
    ** This file may be distributed under the terms of the Q Public License
    ** as defined by Trolltech AS of Norway and appearing in the file
    ** LICENSE.QPL included in the packaging of this file.
    **
    ** This file may be distributed and/or modified under the terms of the
    ** GNU General Public License version 2 as published by the Free Software
    ** Foundation and appearing in the file LICENSE.GPL included in the
    ** packaging of this file.
    **
    ** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
    ** licenses may use this file in accordance with the Qt Commercial License
    ** Agreement provided with the Software.
    **
    ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
    **
    ** See http://www.trolltech.com/pricing.html or email sales@trolltech.com for
    **   information about Qt Commercial License Agreements.
    ** See http://www.trolltech.com/qpl/ for QPL licensing information.
    ** See http://www.trolltech.com/gpl/ for GPL licensing information.
    **
    ** Contact info@trolltech.com if any conditions of this licensing are
    ** not clear to you.
    **
    **********************************************************************/

    #ifndef QMAP_H
    #define QMAP_H

    #ifndef QT_H
    #include "qshared.h"
    #include "qdatastream.h"
    #endif // QT_H

    struct QMapNodeBase
    {
        enum Color { Red, Black };

        QMapNodeBase* left;
        QMapNodeBase* right;
        QMapNodeBase* parent;

        Color color;

        QMapNodeBase* minimum() {
            QMapNodeBase* x = this;
            while ( x->left )
                x = x->left;
            return x;
        }

        QMapNodeBase* maximum() {
            QMapNodeBase* x = this;
            while ( x->right )
                x = x->right;
            return x;
        }
    };

    template <class K, class T>
    struct QMapNode : public QMapNodeBase
    {
        QMapNode( const K& _key, const T& _data ) { data = _data; key = _key; }
        QMapNode( const K& _key )      { key = _key; }
        QMapNode( const QMapNode<K,T>& _n ) { key = _n.key; data = _n.data; }
        QMapNode() { }
        T data;
        K key;
    };

    template<class K, class T>
    class Q_EXPORT QMapIterator
    {
     public:
        /**
         * Typedefs
         */
        typedef QMapNode< K, T >* NodePtr;

        /**
         * Variables
         */
        QMapNode<K,T>* node;

        /**
         * Functions
         */
        QMapIterator() : node( 0 ) {}
        QMapIterator( QMapNode<K,T>* p ) : node( p ) {}
        QMapIterator( const QMapIterator<K,T>& it ) : node( it.node ) {}

        bool operator==( const QMapIterator<K,T>& it ) const { return node == it.node; }
        bool operator!=( const QMapIterator<K,T>& it ) const { return node != it.node; }
        T& operator*() { return node->data; }
        const T& operator*() const { return node->data; }

        // Cannot have this - some compilers are too stupid
        //T* operator->() const { return &(node->data); }

        const K& key() const { return node->key; }
        T& data() { return node->data; }
        const T& data() const { return node->data; }

    private:
        int inc() {
            QMapNodeBase* tmp = node;
            if ( tmp->right ) {
                tmp = tmp->right;
                while ( tmp->left )
                    tmp = tmp->left;
            } else {
                QMapNodeBase* y = tmp->parent;
                while (tmp == y->right) {
                    tmp = y;
                    y = y->parent;
                }
                if (tmp->right != y)
                    tmp = y;
            }
            node = (NodePtr)tmp;
            return 0;
        }

        int dec() {
            QMapNodeBase* tmp = node;
            if (tmp->color == QMapNodeBase::Red &&
                tmp->parent->parent == tmp ) {
                tmp = tmp->right;
            } else if (tmp->left != 0) {
                QMapNodeBase* y = tmp->left;
                while ( y->right )
                    y = y->right;
                tmp = y;
            } else {
                QMapNodeBase* y = tmp->parent;
                while (tmp == y->left) {
                    tmp = y;
                    y = y->parent;
                }
                tmp = y;
            }
            node = (NodePtr)tmp;
            return 0;
        }

    public:
        QMapIterator<K,T>& operator++() {
            inc();
            return *this;
        }

        QMapIterator<K,T> operator++(int) {
            QMapIterator<K,T> tmp = *this;
            inc();
            return tmp;
        }

        QMapIterator<K,T>& operator--() {
            dec();
            return *this;
        }

        QMapIterator<K,T> operator--(int) {
            QMapIterator<K,T> tmp = *this;
            dec();
            return tmp;
        }
    };

    template<class K, class T>
    class Q_EXPORT QMapConstIterator
    {
     public:
        /**
         * Typedefs
         */
        typedef QMapNode< K, T >* NodePtr;

        /**
         * Variables
         */
        QMapNode<K,T>* node;

        /**
         * Functions
         */
        QMapConstIterator() : node( 0 ) {}
        QMapConstIterator( QMapNode<K,T>* p ) : node( p ) {}
        QMapConstIterator( const QMapConstIterator<K,T>& it ) : node( it.node ) {}
        QMapConstIterator( const QMapIterator<K,T>& it ) : node( it.node ) {}

        bool operator==( const QMapConstIterator<K,T>& it ) const { return node == it.node; }
        bool operator!=( const QMapConstIterator<K,T>& it ) const { return node != it.node; }
        const T& operator*()  const { return node->data; }

        // Cannot have this - some compilers are too stupid
        //const T* operator->() const { return &(node->data); }

        const K& key() const { return node->key; }
        const T& data() const { return node->data; }

    private:
        int inc() {
            QMapNodeBase* tmp = node;
            if ( tmp->right ) {
                tmp = tmp->right;
                while ( tmp->left )
                    tmp = tmp->left;
            } else {
                QMapNodeBase* y = tmp->parent;
                while (tmp == y->right) {
                    tmp = y;
                    y = y->parent;
                }
                if (tmp->right != y)
                    tmp = y;
            }
            node = (NodePtr)tmp;
            return 0;
        }

        int dec() {
            QMapNodeBase* tmp = node;
            if (tmp->color == QMapNodeBase::Red &&
                tmp->parent->parent == tmp ) {
                tmp = tmp->right;
            } else if (tmp->left != 0) {
                QMapNodeBase* y = tmp->left;
                while ( y->right )
                    y = y->right;
                tmp = y;
            } else {
                QMapNodeBase* y = tmp->parent;
                while (tmp == y->left) {
                    tmp = y;
                    y = y->parent;
                }
                tmp = y;
            }
            node = (NodePtr)tmp;
            return 0;
        }

    public:
        QMapConstIterator<K,T>& operator++() {
            inc();
            return *this;
        }

        QMapConstIterator<K,T> operator++(int) {
            QMapConstIterator<K,T> tmp = *this;
            inc();
            return tmp;
        }

        QMapConstIterator<K,T>& operator--() {
            dec();
            return *this;
        }

        QMapConstIterator<K,T> operator--(int) {
            QMapConstIterator<K,T> tmp = *this;
            dec();
            return tmp;
        }
    };

    class Q_EXPORT QMapPrivateBase : public QShared
    {
    public:
        QMapPrivateBase() {
            node_count = 0;
        }
        QMapPrivateBase( const QMapPrivateBase* _map) {
            node_count = _map->node_count;
        }

        /**
         * Implementations of basic tree algorithms
         */
        void rotateLeft( QMapNodeBase* x, QMapNodeBase*& root);
        void rotateRight( QMapNodeBase* x, QMapNodeBase*& root );
        void rebalance( QMapNodeBase* x, QMapNodeBase*& root );
        QMapNodeBase* removeAndRebalance( QMapNodeBase* z, QMapNodeBase*& root,
                                          QMapNodeBase*& leftmost,
                                          QMapNodeBase*& rightmost );

        /**
         * Variables
         */
        int node_count;
    };

    template <class Key, class T>
    class QMapPrivate : public QMapPrivateBase
    {
    public:
        /**
         * Typedefs
         */
        typedef QMapIterator< Key, T > Iterator;
        typedef QMapConstIterator< Key, T > ConstIterator;
        typedef QMapNode< Key, T > Node;
        typedef QMapNode< Key, T >* NodePtr;

        /**
         * Functions
         */
        QMapPrivate() {
            header = new Node;
            header->color = QMapNodeBase::Red; // Mark the header
            header->parent = 0;
            header->left = header->right = header;
        }
        QMapPrivate( const QMapPrivate< Key, T >* _map ) : QMapPrivateBase( _map ) {
            header = new Node;
            header->color = QMapNodeBase::Red; // Mark the header
            if ( _map->header->parent == 0 ) {
                header->parent = 0;
                header->left = header->right = header;
            } else {
                header->parent = copy( (NodePtr)(_map->header->parent) );
                header->parent->parent = header;
                header->left = header->parent->minimum();
                header->right = header->parent->maximum();
            }
        }
        ~QMapPrivate() { clear(); delete header; }

        NodePtr copy( NodePtr p ) {
            if ( !p )
                return 0;
            NodePtr n = new Node( *p );
            n->color = p->color;
            if ( p->left ) {
                n->left = copy( (NodePtr)(p->left) );
                n->left->parent = n;
            } else {
                n->left = 0;
            }
            if ( p->right ) {
                n->right = copy( (NodePtr)(p->right) );
                n->right->parent = n;
            } else {
                n->right = 0;
            }
            return n;
        }

        void clear() {
            clear( (NodePtr)(header->parent) );
            header->color = QMapNodeBase::Red;
            header->parent = 0;
            header->left = header->right = header;
            node_count = 0;
        }

        void clear( NodePtr p ) {
            while ( p != 0 ) {
                clear( (NodePtr)p->right );
                NodePtr y = (NodePtr)p->left;
                delete p;
                p = y;
            }
        }

        Iterator begin()    { return Iterator( (NodePtr)(header->left ) ); }
        Iterator end()      { return Iterator( header ); }
        ConstIterator begin() const { return ConstIterator( (NodePtr)(header->left ) ); }
        ConstIterator end() const { return ConstIterator( header ); }

        ConstIterator find(const Key& k) const {
            QMapNodeBase* y = header;        // Last node
            QMapNodeBase* x = header->parent; // Root node.

            while ( x != 0 ) {
                // If as k <= key(x) go left
                if ( !( key(x) < k ) ) {
                    y = x;
                    x = x->left;
                } else {
                    x = x->right;
                }
            }

            // Was k bigger/smaller then the biggest/smallest
            // element of the tree ? Return end()
            if ( y == header || k < key(y) )
                return ConstIterator( header );
            return ConstIterator( (NodePtr)y );
        }

        void remove( Iterator it ) {
            NodePtr del = (NodePtr) removeAndRebalance( it.node, header->parent, header->left, header->right );
            delete del;
            --node_count;
        }

    #ifdef QT_QMAP_DEBUG
        void inorder( QMapNodeBase* x = 0, int level = 0 ){
            if ( !x )
                x = header->parent;
            if ( x->left )
                inorder( x->left, level + 1 );
        //cout << level << " Key=" << key(x) << " Value=" << ((NodePtr)x)->data << endl;
            if ( x->right )
                inorder( x->right, level + 1 );
        }
    #endif

        Iterator insertMulti(const Key& v){
            QMapNodeBase* y = header;
            QMapNodeBase* x = header->parent;
            while (x != 0){
                y = x;
                x = ( v < key(x) ) ? x->left : x->right;
            }
            return insert(x, y, v);
        }

        Iterator insertSingle( const Key& k ) {
            // Search correct position in the tree
            QMapNodeBase* y = header;
            QMapNodeBase* x = header->parent;
            bool result = TRUE;
            while ( x != 0 ) {
                result = ( k < key(x) );
                y = x;
                x = result ? x->left : x->right;
            }
            // Get iterator on the last not empty one
            Iterator j( (NodePtr)y );
            if ( result ) {
                // Smaller then the leftmost one ?
                if ( j == begin() ) {
                    return insert(x, y, k );
                } else {
                    // Perhaps daddy is the right one ?
                    --j;
                }
            }
            // Really bigger ?
            if ( (j.node->key) < k )
                return insert(x, y, k );
            // We are going to replace a node
            return j;
        }

        Iterator insert( QMapNodeBase* x, QMapNodeBase* y, const Key& k ) {
            NodePtr z = new Node( k );
            if (y == header || x != 0 || k < key(y) ) {
                y->left = z;                // also makes leftmost = z when y == header
                if ( y == header ) {
                    header->parent = z;
                    header->right = z;
                } else if ( y == header->left )
                    header->left = z;           // maintain leftmost pointing to min node
            } else {
                y->right = z;
                if ( y == header->right )
                    header->right = z;          // maintain rightmost pointing to max node
            }
            z->parent = y;
            z->left = 0;
            z->right = 0;
            rebalance( z, header->parent );
            ++node_count;
            return Iterator(z);
        }

    protected:
        /**
         * Helpers
         */
        const Key& key( QMapNodeBase* b ) const { return ((NodePtr)b)->key; }

        /**
         * Variables
         */
        NodePtr header;
    };

    template<class Key, class T>
    class Q_EXPORT QMap
    {
    public:
        /**
         * Typedefs
         */
        typedef QMapIterator< Key, T > Iterator;
        typedef QMapConstIterator< Key, T > ConstIterator;
        typedef T ValueType;
        typedef QMapPrivate< Key, T > Priv;

        /**
         * API
         */
        QMap() { sh = new QMapPrivate< Key, T >; }
        QMap( const QMap<Key,T>& m ) { sh = m.sh; sh->ref(); }
        ~QMap() { if ( sh->deref() ) delete sh; }

        QMap<Key,T>& operator= ( const QMap<Key,T>& m )
          { m.sh->ref(); if ( sh->deref() ) delete sh; sh = m.sh; return *this; }

        Iterator begin() { detach(); return sh->begin(); }
        Iterator end() { detach(); return sh->end(); }
        ConstIterator begin() const { return ((const Priv*)sh)->begin(); }
        ConstIterator end() const { return ((const Priv*)sh)->end(); }

        Iterator find ( const Key& k )
            { detach(); return Iterator( sh->find( k ).node ); }
        ConstIterator find ( const Key& k ) const
            { return sh->find( k ); }
        T& operator[] ( const Key& k ) {
            detach(); QMapNode<Key,T>* p = sh->find( k ).node;
            if ( p != sh->end().node ) return p->data;
            return insert( k, T() ).data(); }
        const T& operator[] ( const Key& k ) const
            { return sh->find( k ).data(); }
        bool contains ( const Key& k ) const
            { return find( k ) != end(); }
            //{ return sh->find( k ) != ((const Priv*)sh)->end(); }

        uint count() const { return sh->node_count; }

        bool isEmpty() const { return sh->node_count == 0; }

        Iterator insert( const Key& key, const T& value ) {
            detach();
            Iterator it = sh->insertSingle( key );
            it.data() = value;
            return it;
        }

        void remove( Iterator it ) { detach(); sh->remove( it ); }
        void remove( const Key& k ) {
            detach();
            Iterator it( sh->find( k ).node );
            if ( it != end() )
                sh->remove( it );
        }

        Iterator replace( const Key& k, const T& v ) {
            remove( k );
            return insert( k, v );
        }

        void clear() { if ( sh->count == 1 ) sh->clear(); else { sh->deref(); sh = new QMapPrivate<Key,T>; } }

    #if defined(Q_FULL_TEMPLATE_INSTANTIATION)
        bool operator==( const QMap<Key,T>& ) const { return FALSE; }
    #endif

    protected:
        /**
         * Helpers
         */
        void detach() { if ( sh->count > 1 ) { sh->deref(); sh = new QMapPrivate<Key,T>( sh ); } }

        Priv* sh;
    };

    #ifndef QT_NO_DATASTREAM
    template<class Key, class T>
    inline QDataStream& operator>>( QDataStream& s, QMap<Key,T>& m ) {
        m.clear();
        Q_UINT32 c;
        s >> c;
        for( Q_UINT32 i = 0; i < c; ++i ) {
            Key k; T t;
            s >> k >> t;
            m.insert( k, t );
        }
        return s;
    }

    template<class Key, class T>
    inline QDataStream& operator<<( QDataStream& s, const QMap<Key,T>& m ) {
        s << (Q_UINT32)m.count();
        QMapConstIterator<Key,T> it = m.begin();
        for( ; it != m.end(); ++it )
            s << it.key() << it.data();
        return s;
    }
    #endif

    #endif // QMAP_H