// 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)
based on code by Marc Shapiro (shapiro@sor.inria.fr)
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.
// Plexes are made out of <T>IChunks
//public: // kludge until C++ `protected' policies settled
<T>* data; // data, from client
int base; // lowest possible index
int low; // lowest valid index
int fence; // highest valid index + 1
int top; // highest possible index + 1
<T>IChunk* nxt; // circular links
<T>IChunk(<T>* d, // ptr to array of elements
int base_idx, // initial indices
int size() const; // number of slots
virtual int empty() const ;
virtual int full() const ;
int can_grow_high () const ; // there is space to add data
int can_grow_low () const;
int base_index() const; // lowest possible index;
int low_index() const; // lowest actual index;
virtual int first_index() const; // lowest valid index or fence if none
virtual int last_index() const; // highest valid index or low-1 if none
int fence_index() const; // highest actual index + 1
int top_index() const; // highest possible index + 1
int possible_index(int i) const; // i between base and top
int actual_index(int i) const; // i between low and fence
virtual int valid_index(int i) const; // i not deleted (mainly for mchunks)
int possible_pointer(const <T>* p) const; // same for ptr
int actual_pointer(const <T>* p) const;
virtual int valid_pointer(const <T>* p) const;
<T>* pointer_to(int i) const ; // pointer to data indexed by i
// caution: i is not checked for validity
int index_of(const <T>* p) const; // index of data pointed to by p
// caution: p is not checked for validity
virtual int succ(int idx) const; // next valid index or fence if none
virtual int pred(int idx) const; // previous index or low - 1 if none
virtual <T>* first_pointer() const; // pointer to first valid pos or 0
virtual <T>* last_pointer() const; // pointer to first valid pos or 0
virtual <T>* succ(<T>* p) const; // next pointer or 0
virtual <T>* pred(<T>* p) const; // previous pointer or 0
virtual <T>* grow_high (); // return spot to add an element
virtual <T>* grow_low ();
virtual void shrink_high (); // logically delete top index
virtual void shrink_low ();
virtual void clear(int lo); // reset to empty ch with base = lo
virtual void cleardown(int hi); // reset to empty ch with top = hi
void re_index(int lo); // re-index so lo is new low
void link_to_prev(<T>IChunk* prev);
void link_to_next(<T>IChunk* next);
<T>* invalidate(); // mark self as invalid; return data
virtual int OK() const; // representation invariant
void error(const char*) const;
void empty_error() const;
void index_error() const;
// <T>Plex is a partly `abstract' class: few of the virtuals
// are implemented at the Plex level, only in the subclasses
<T>IChunk* hd; // a chunk holding the data
int fnc; // highest index + 1
int csize; // size of the chunk
void invalidate(); // mark so OK() is false
void del_chunk(<T>IChunk*); // delete a chunk
<T>IChunk* tl() const; // last chunk;
int one_chunk() const; // true if hd == tl()
virtual <T>& operator [] (int idx) = 0; // access by index;
virtual <T>& operator () (Pix p) = 0; // access by Pix;
virtual <T>& high_element () = 0; // access high element
virtual <T>& low_element () = 0; // access low element
// read-only versions for const Plexes
virtual const <T>& operator [] (int idx) const = 0; // access by index;
virtual const <T>& operator () (Pix p) const = 0; // access by Pix;
virtual const <T>& high_element () const = 0; // access high element
virtual const <T>& low_element () const = 0; // access low element
virtual int valid (int idx) const = 0; // idx is an OK index
virtual int low() const = 0; // lowest index or fence if none
virtual int high() const = 0; // highest index or low-1 if none
int ecnef() const; // low limit index (low-1)
int fence() const; // high limit index (high+1)
virtual void prev(int& idx) const= 0; // set idx to preceding index
// caution: pred may be out of bounds
virtual void next(int& idx) const = 0; // set to next index
// caution: succ may be out of bounds
virtual Pix first() const = 0; // Pix to low element or 0
virtual Pix last() const = 0; // Pix to high element or 0
virtual void prev(Pix& pix) const = 0; // preceding pix or 0
virtual void next(Pix& pix) const = 0; // next pix or 0
virtual int owns(Pix p) const = 0; // p is an OK Pix
virtual int Pix_to_index(Pix p) const = 0; // get index via Pix
virtual Pix index_to_Pix(int idx) const = 0; // Pix via index
virtual int add_high(const <T&> elem) =0;// add new element at high end
virtual int add_low(const <T&> elem) = 0; // add new low element,
virtual int del_high() = 0; // remove the element at high end
virtual int del_low() = 0; // delete low element, return new lo
// immediately call <T>::~<T>
// operations on multiple elements
virtual void fill(const <T&> x); // set all elements = x
virtual void fill(const <T&> x, int from, int to); // fill from to to
virtual void clear() = 0; // reset to zero-sized Plex
virtual int reset_low(int newlow); // change low index,return old
virtual void reverse(); // reverse in-place
virtual void append(const <T>Plex& a); // concatenate a copy
virtual void prepend(const <T>Plex& a); // prepend a copy
virtual int can_add_high() const = 0;
virtual int can_add_low() const = 0;
int length () const; // number of slots
int empty () const; // is the plex empty?
virtual int full() const = 0; // it it full?
int chunk_size() const; // report chunk size;
virtual int OK() const = 0; // representation invariant
void error(const char* msg) const;
void index_error() const;
void empty_error() const;
inline int <T>IChunk:: size() const
inline int <T>IChunk:: base_index() const
inline int <T>IChunk:: low_index() const
inline int <T>IChunk:: fence_index() const
inline int <T>IChunk:: top_index() const
inline <T>* <T>IChunk:: pointer_to(int i) const
inline int <T>IChunk:: index_of(const <T>* p) const
return ((int)p - (int)data) / sizeof(<T>) + base;
inline int <T>IChunk:: possible_index(int i) const
return i >= base && i < top;
inline int <T>IChunk:: possible_pointer(const <T>* p) const
return p >= data && p < &(data[top-base]);
inline int <T>IChunk:: actual_index(int i) const
return i >= low && i < fence;
inline int <T>IChunk:: actual_pointer(const <T>* p) const
return p >= data && p < &(data[fence-base]);
inline int <T>IChunk:: can_grow_high () const
inline int <T>IChunk:: can_grow_low () const
inline <T>* <T>IChunk:: invalidate()
inline <T>IChunk* <T>IChunk::prev() const
inline <T>IChunk* <T>IChunk::next() const
inline void <T>IChunk::link_to_prev(<T>IChunk* prev)
inline void <T>IChunk::link_to_next(<T>IChunk* next)
inline void <T>IChunk::unlink()
inline int <T>IChunk:: empty() const
inline int <T>IChunk:: full() const
return top - base == fence - low;
inline int <T>IChunk:: first_index() const
return (low == fence)? fence : low;
inline int <T>IChunk:: last_index() const
return (low == fence)? low - 1 : fence - 1;
inline int <T>IChunk:: succ(int i) const
return (i < low) ? low : i + 1;
inline int <T>IChunk:: pred(int i) const
return (i > fence) ? (fence - 1) : i - 1;
inline int <T>IChunk:: valid_index(int i) const
return i >= low && i < fence;
inline int <T>IChunk:: valid_pointer(const <T>* p) const
return p >= &(data[low - base]) && p < &(data[fence - base]);
inline <T>* <T>IChunk:: grow_high ()
if (!can_grow_high()) full_error();
return &(data[fence++ - base]);
inline <T>* <T>IChunk:: grow_low ()
if (!can_grow_low()) full_error();
return &(data[--low - base]);
inline void <T>IChunk:: shrink_high ()
if (empty()) empty_error();
inline void <T>IChunk:: shrink_low ()
if (empty()) empty_error();
inline <T>* <T>IChunk::first_pointer() const
return (low == fence)? 0 : &(data[low - base]);
inline <T>* <T>IChunk::last_pointer() const
return (low == fence)? 0 : &(data[fence - base - 1]);
inline <T>* <T>IChunk::succ(<T>* p) const
return ((p+1) < &(data[low - base]) || (p+1) >= &(data[fence - base])) ?
inline <T>* <T>IChunk::pred(<T>* p) const
return ((p-1) < &(data[low - base]) || (p-1) >= &(data[fence - base])) ?
// generic Plex operations
inline <T>Plex::<T>Plex() {}
inline int <T>Plex::chunk_size() const
inline int <T>Plex::ecnef () const
inline int <T>Plex::fence () const
inline int <T>Plex::length () const
inline int <T>Plex::empty () const
inline <T>IChunk* <T>Plex::tl() const
inline int <T>Plex::one_chunk() const