qglist.h

/****************************************************************************
** $Id: qglist.h,v 2.4 1998/07/03 00:09:45 hanord Exp $
**
** Definition of QGList and QGListIterator classes
**
** Created : 920624
**
** Copyright (C) 1992-1998 Troll Tech AS.  All rights reserved.
**
** This file is part of Qt Free Edition, version 1.40.
**
** See the file LICENSE included in the distribution for the usage
** and distribution terms, or http://www.troll.no/free-license.html.
**
** IMPORTANT NOTE: You may NOT copy this file or any part of it into
** your own programs or libraries.
**
** Please see http://www.troll.no/pricing.html for information about 
** Qt Professional Edition, which is this same library but with a
** license which allows creation of commercial/proprietary software.
**
*****************************************************************************/

#ifndef QGLIST_H
#define QGLIST_H

#ifndef QT_H
#include "qcollection.h"
#endif // QT_H


/*****************************************************************************
  QLNode class (internal doubly linked list node)
 *****************************************************************************/

class QLNode
{
friend class QGList;
friend class QGListIterator;
public:
    GCI     getData()   { return data; }
private:
    GCI     data;
    QLNode *prev;
    QLNode *next;
    QLNode( GCI d )     { data = d; }
};


/*****************************************************************************
  QGList class
 *****************************************************************************/

class QGList : public QCollection               // doubly linked generic list
{
friend class QGListIterator;
friend class QGVector;                          // needed by QGVector::toList
public:
    uint  count() const;                        // return number of nodes

    QDataStream &read( QDataStream & );         // read list from stream
    QDataStream &write( QDataStream & ) const;  // write list to stream

protected:
    QGList();                                   // create empty list
    QGList( const QGList & );                   // make copy of other list
   ~QGList();

    QGList &operator=( const QGList & );        // assign from other list

    void  inSort( GCI );                        // add item sorted in list
    void  append( GCI );                        // add item at end of list
    bool  insertAt( uint index, GCI );          // add item at i'th position
    void  relinkNode( QLNode * );               // relink as first item
    bool  removeNode( QLNode * );               // remove node
    bool  remove( GCI = 0 );                    // remove item (0=current)
    bool  removeRef( GCI = 0 );                 // remove item (0=current)
    bool  removeFirst();                        // remove first item
    bool  removeLast();                         // remove last item
    bool  removeAt( uint index );               // remove item at i'th position
    GCI   takeNode( QLNode * );                 // take out node
    GCI   take();                               // take out current item
    GCI   takeAt( uint index );                 // take out item at i'th pos
    GCI   takeFirst();                          // take out first item
    GCI   takeLast();                           // take out last item

    void  clear();                              // remove all items

    int   findRef( GCI, bool = TRUE );          // find exact item in list
    int   find( GCI, bool = TRUE );             // find equal item in list

    uint  containsRef( GCI )    const;          // get number of exact matches
    uint  contains( GCI )       const;          // get number of equal matches

    GCI   at( uint index );                     // access item at i'th pos
    int   at() const;                           // get current index
    QLNode *currentNode() const;                // get current node

    GCI   get() const;                          // get current item

    GCI   cfirst() const;                       // get ptr to first list item
    GCI   clast()  const;                       // get ptr to last list item
    GCI   first();                              // set first item in list curr
    GCI   last();                               // set last item in list curr
    GCI   next();                               // set next item in list curr
    GCI   prev();                               // set prev item in list curr

    void  toVector( QGVector * ) const;         // put items in vector

    virtual int compareItems( GCI, GCI );

    virtual QDataStream &read( QDataStream &, GCI & );
    virtual QDataStream &write( QDataStream &, GCI ) const;

private:
    void  prepend( GCI );                       // add item at start of list

    QLNode *firstNode;                          // first node
    QLNode *lastNode;                           // last node
    QLNode *curNode;                            // current node
    int     curIndex;                           // current index
    uint    numNodes;                           // number of nodes
    QGList *iterators;                          // list of iterators

    QLNode *locate( uint );                     // get node at i'th pos
    QLNode *unlink();                           // unlink node
};


inline uint QGList::count() const
{
    return numNodes;
}

inline bool QGList::removeFirst()
{
    first();
    return remove();
}

inline bool QGList::removeLast()
{
    last();
    return remove();
}

inline int QGList::at() const
{
    return curIndex;
}

inline GCI QGList::at( uint index )
{
    QLNode *n = locate( index );
    return n ? n->data : 0;
}

inline QLNode *QGList::currentNode() const
{
    return curNode;
}

inline GCI QGList::get() const
{
    return curNode ? curNode->data : 0;
}

inline GCI QGList::cfirst() const
{
    return firstNode ? firstNode->data : 0;
}

inline GCI QGList::clast() const
{
    return lastNode ? lastNode->data : 0;
}


/*****************************************************************************
  QGList stream functions
 *****************************************************************************/

QDataStream &operator>>( QDataStream &, QGList & );
QDataStream &operator<<( QDataStream &, const QGList & );


/*****************************************************************************
  QGListIterator class
 *****************************************************************************/

class QGListIterator                            // QGList iterator
{
friend class QGList;
protected:
    QGListIterator( const QGList & );
    QGListIterator( const QGListIterator & );
    QGListIterator &operator=( const QGListIterator & );
   ~QGListIterator();

    bool  atFirst() const;                      // test if at first item
    bool  atLast()  const;                      // test if at last item
    GCI   toFirst();                            // move to first item
    GCI   toLast();                             // move to last item

    GCI   get() const;                          // get current item
    GCI   operator()();                         // get current and move to next
    GCI   operator++();                         // move to next item (prefix)
    GCI   operator+=(uint);                     // move n positions forward
    GCI   operator--();                         // move to prev item (prefix)
    GCI   operator-=(uint);                     // move n positions backward

protected:
    QGList *list;                               // reference to list

private:
    QLNode  *curNode;                           // current node in list
};


inline bool QGListIterator::atFirst() const
{
    return curNode == list->firstNode;
}

inline bool QGListIterator::atLast() const
{
    return curNode == list->lastNode;
}

inline GCI QGListIterator::get() const
{
    return curNode ? curNode->data : 0;
}


#endif  // QGLIST_H