freebsd-dev/gnu/lib/libg++/include/DLList.h
1995-05-30 05:05:38 +00:00

138 lines
4.4 KiB
C++

// This may look like C code, but it is really -*- C++ -*-
/*
Copyright (C) 1988 Free Software Foundation
written by Doug Lea (dl@rocky.oswego.edu)
This file is part of the GNU C++ Library. This library is free
software; you can redistribute it and/or modify it under the terms of
the GNU Library General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version. This library 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 Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free Software
Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _DLList_h
#ifdef __GNUG__
//#pragma interface
#endif
#define _DLList_h 1
#include <Pix.h>
struct BaseDLNode {
BaseDLNode *bk;
BaseDLNode *fd;
void *item() {return (void*)(this+1);} //Return ((DLNode<T>*)this)->hd
};
template<class T>
class DLNode : public BaseDLNode
{
public:
T hd;
DLNode() { }
DLNode(const T& h, DLNode* p = 0, DLNode* n = 0)
: hd(h) { bk = p; fd = n; }
~DLNode() { }
};
class BaseDLList {
protected:
BaseDLNode *h;
BaseDLList() { h = 0; }
void copy(const BaseDLList&);
BaseDLList& operator= (const BaseDLList& a);
virtual void delete_node(BaseDLNode*node) = 0;
virtual BaseDLNode* copy_node(const void* datum) = 0;
virtual void copy_item(void *dst, void *src) = 0;
virtual ~BaseDLList() { }
Pix prepend(const void*);
Pix append(const void*);
Pix ins_after(Pix p, const void *datum);
Pix ins_before(Pix p, const void *datum);
void remove_front(void *dst);
void remove_rear(void *dst);
void join(BaseDLList&);
public:
int empty() const { return h == 0; }
int length() const;
void clear();
void error(const char* msg) const;
int owns(Pix p) const;
int OK() const;
void del(Pix& p, int dir = 1);
void del_after(Pix& p);
void del_front();
void del_rear();
};
template <class T>
class DLList : public BaseDLList {
//friend class <T>DLListTrav;
virtual void delete_node(BaseDLNode *node) { delete (DLNode<T>*)node; }
virtual BaseDLNode* copy_node(const void *datum)
{ return new DLNode<T>(*(const T*)datum); }
virtual void copy_item(void *dst, void *src) { *(T*)dst = *(T*)src; }
public:
DLList() : BaseDLList() { }
DLList(const DLList<T>& a) : BaseDLList() { copy(a); }
DLList<T>& operator = (const DLList<T>& a)
{ BaseDLList::operator=((const BaseDLList&) a); return *this; }
virtual ~DLList() { clear(); }
Pix prepend(const T& item) {return BaseDLList::prepend(&item);}
Pix append(const T& item) {return BaseDLList::append(&item);}
void join(DLList<T>& a) { BaseDLList::join(a); }
T& front() {
if (h == 0) error("front: empty list");
return ((DLNode<T>*)h)->hd; }
T& rear() {
if (h == 0) error("rear: empty list");
return ((DLNode<T>*)h->bk)->hd;
}
const T& front() const {
if (h == 0) error("front: empty list");
return ((DLNode<T>*)h)->hd; }
const T& rear() const {
if (h == 0) error("rear: empty list");
return ((DLNode<T>*)h->bk)->hd;
}
T remove_front() { T dst; BaseDLList::remove_front(&dst); return dst; }
T remove_rear() { T dst; BaseDLList::remove_rear(&dst); return dst; }
T& operator () (Pix p) {
if (p == 0) error("null Pix");
return ((DLNode<T>*)p)->hd;
}
const T& operator () (Pix p) const {
if (p == 0) error("null Pix");
return ((DLNode<T>*)p)->hd;
}
Pix first() const { return Pix(h); }
Pix last() const { return (h == 0) ? 0 : Pix(h->bk); }
void next(Pix& p) const
{ p = (p == 0 || p == h->bk)? 0 : Pix(((DLNode<T>*)p)->fd); }
void prev(Pix& p) const
{ p = (p == 0 || p == h)? 0 : Pix(((DLNode<T>*)p)->bk); }
Pix ins_after(Pix p, const T& item)
{return BaseDLList::ins_after(p, &item); }
Pix ins_before(Pix p, const T& item)
{return BaseDLList::ins_before(p, &item);}
};
#endif