modules/up/src/gnug++/unsigned.Plex.h
/* [<][>][^][v][top][bottom][index][help] */
FUNCTIONS
This source file includes following functions.
- unsignedIChunk
- unsignedPlex
- size
- base_index
- low_index
- fence_index
- top_index
- pointer_to
- index_of
- possible_index
- possible_pointer
- actual_index
- actual_pointer
- can_grow_high
- can_grow_low
- invalidate
- prev
- next
- link_to_prev
- link_to_next
- unlink
- empty
- full
- first_index
- last_index
- succ
- pred
- valid_index
- valid_pointer
- grow_high
- grow_low
- shrink_high
- shrink_low
- first_pointer
- last_pointer
- succ
- pred
- chunk_size
- ecnef
- fence
- length
- empty
- tl
- one_chunk
// 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, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifndef _unsignedPlex_h
#ifdef __GNUG__
#pragma interface
#endif
#define _unsignedPlex_h 1
#include "std.h"
#include "Pix.h"
#include "unsigned.defs.h"
// Plexes are made out of unsignedIChunks
#include <stddef.h>
class unsignedIChunk
/* [<][>][^][v][top][bottom][index][help] */
{
//public: // kludge until C++ `protected' policies settled
protected:
unsigned* 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
unsignedIChunk* nxt; // circular links
unsignedIChunk* prv;
public:
// constructors
unsignedIChunk(unsigned* d, // ptr to array of elements
int base_idx, // initial indices
int low_idx,
int fence_idx,
int top_idx);
virtual ~unsignedIChunk();
// status reports
int size() const; // number of slots
inline virtual int empty() const ;
inline 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;
inline virtual int first_index() const; // lowest valid index or fence if none
inline 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
// indexing conversion
int possible_index(int i) const; // i between base and top
int actual_index(int i) const; // i between low and fence
inline virtual int valid_index(int i) const; // i not deleted (mainly for mchunks)
int possible_pointer(const unsigned* p) const; // same for ptr
int actual_pointer(const unsigned* p) const;
inline virtual int valid_pointer(const unsigned* p) const;
unsigned* pointer_to(int i) const ; // pointer to data indexed by i
// caution: i is not checked for validity
int index_of(const unsigned* p) const; // index of data pointed to by p
// caution: p is not checked for validity
inline virtual int succ(int idx) const; // next valid index or fence if none
inline virtual int pred(int idx) const; // previous index or low - 1 if none
inline virtual unsigned* first_pointer() const; // pointer to first valid pos or 0
inline virtual unsigned* last_pointer() const; // pointer to first valid pos or 0
inline virtual unsigned* succ(unsigned* p) const; // next pointer or 0
inline virtual unsigned* pred(unsigned* p) const; // previous pointer or 0
// modification
inline virtual unsigned* grow_high (); // return spot to add an element
inline virtual unsigned* grow_low ();
inline virtual void shrink_high (); // logically delete top index
inline 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
// chunk traversal
unsignedIChunk* next() const;
unsignedIChunk* prev() const;
void link_to_prev(unsignedIChunk* prev);
void link_to_next(unsignedIChunk* next);
void unlink();
// state checks
unsigned* invalidate(); // mark self as invalid; return data
// for possible deletion
virtual int OK() const; // representation invariant
void error(const char*) const;
void empty_error() const;
void full_error() const;
void index_error() const;
};
// unsignedPlex is a partly `abstract' class: few of the virtuals
// are implemented at the Plex level, only in the subclasses
class unsignedPlex
/* [<][>][^][v][top][bottom][index][help] */
{
protected:
unsignedIChunk* hd; // a chunk holding the data
int lo; // lowest index
int fnc; // highest index + 1
int csize; // size of the chunk
void invalidate(); // mark so OK() is false
void del_chunk(unsignedIChunk*); // delete a chunk
unsignedIChunk* tl() const; // last chunk;
int one_chunk() const; // true if hd == tl()
public:
// constructors, etc.
unsignedPlex(); // no-op
virtual ~unsignedPlex();
// Access functions
virtual unsigned& operator [] (int idx) = 0; // access by index;
virtual unsigned& operator () (Pix p) = 0; // access by Pix;
virtual unsigned& high_element () = 0; // access high element
virtual unsigned& low_element () = 0; // access low element
// read-only versions for const Plexes
virtual const unsigned& operator [] (int idx) const = 0; // access by index;
virtual const unsigned& operator () (Pix p) const = 0; // access by Pix;
virtual const unsigned& high_element () const = 0; // access high element
virtual const unsigned& low_element () const = 0; // access low element
// Index functions
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
// index<->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
// Growth
virtual int add_high(const unsigned elem) =0;// add new element at high end
// return new high
virtual int add_low(const unsigned elem) = 0; // add new low element,
// return new low
// Shrinkage
virtual int del_high() = 0; // remove the element at high end
// return new high
virtual int del_low() = 0; // delete low element, return new lo
// caution: del_low/high
// does not necessarily
// immediately call unsigned::~unsigned
// operations on multiple elements
virtual void fill(const unsigned x); // set all elements = x
virtual void fill(const unsigned 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 unsignedPlex& a); // concatenate a copy
virtual void prepend(const unsignedPlex& a); // prepend a copy
// status
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;
void full_error() const;
};
// unsignedIChunk ops
inline int unsignedIChunk:: size() const
/* [<][>][^][v][top][bottom][index][help] */
{
return top - base;
}
inline int unsignedIChunk:: base_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return base;
}
inline int unsignedIChunk:: low_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return low;
}
inline int unsignedIChunk:: fence_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return fence;
}
inline int unsignedIChunk:: top_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return top;
}
inline unsigned* unsignedIChunk:: pointer_to(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return &(data[i-base]);
}
inline int unsignedIChunk:: index_of(const unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return ((int)p - (int)data) / sizeof(unsigned) + base;
}
inline int unsignedIChunk:: possible_index(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return i >= base && i < top;
}
inline int unsignedIChunk:: possible_pointer(const unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return p >= data && p < &(data[top-base]);
}
inline int unsignedIChunk:: actual_index(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return i >= low && i < fence;
}
inline int unsignedIChunk:: actual_pointer(const unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return p >= data && p < &(data[fence-base]);
}
inline int unsignedIChunk:: can_grow_high () const
/* [<][>][^][v][top][bottom][index][help] */
{
return fence < top;
}
inline int unsignedIChunk:: can_grow_low () const
/* [<][>][^][v][top][bottom][index][help] */
{
return base < low;
}
inline unsigned* unsignedIChunk:: invalidate()
/* [<][>][^][v][top][bottom][index][help] */
{
unsigned* p = data;
data = 0;
return p;
}
inline unsignedIChunk* unsignedIChunk::prev() const
/* [<][>][^][v][top][bottom][index][help] */
{
return prv;
}
inline unsignedIChunk* unsignedIChunk::next() const
/* [<][>][^][v][top][bottom][index][help] */
{
return nxt;
}
inline void unsignedIChunk::link_to_prev(unsignedIChunk* prev)
/* [<][>][^][v][top][bottom][index][help] */
{
nxt = prev->nxt;
prv = prev;
nxt->prv = this;
prv->nxt = this;
}
inline void unsignedIChunk::link_to_next(unsignedIChunk* next)
/* [<][>][^][v][top][bottom][index][help] */
{
prv = next->prv;
nxt = next;
nxt->prv = this;
prv->nxt = this;
}
inline void unsignedIChunk::unlink()
/* [<][>][^][v][top][bottom][index][help] */
{
unsignedIChunk* n = nxt;
unsignedIChunk* p = prv;
n->prv = p;
p->nxt = n;
prv = nxt = this;
}
inline int unsignedIChunk:: empty() const
/* [<][>][^][v][top][bottom][index][help] */
{
return low == fence;
}
inline int unsignedIChunk:: full() const
/* [<][>][^][v][top][bottom][index][help] */
{
return top - base == fence - low;
}
inline int unsignedIChunk:: first_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return (low == fence)? fence : low;
}
inline int unsignedIChunk:: last_index() const
/* [<][>][^][v][top][bottom][index][help] */
{
return (low == fence)? low - 1 : fence - 1;
}
inline int unsignedIChunk:: succ(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return (i < low) ? low : i + 1;
}
inline int unsignedIChunk:: pred(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return (i > fence) ? (fence - 1) : i - 1;
}
inline int unsignedIChunk:: valid_index(int i) const
/* [<][>][^][v][top][bottom][index][help] */
{
return i >= low && i < fence;
}
inline int unsignedIChunk:: valid_pointer(const unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return p >= &(data[low - base]) && p < &(data[fence - base]);
}
inline unsigned* unsignedIChunk:: grow_high ()
/* [<][>][^][v][top][bottom][index][help] */
{
if (!can_grow_high()) full_error();
return &(data[fence++ - base]);
}
inline unsigned* unsignedIChunk:: grow_low ()
/* [<][>][^][v][top][bottom][index][help] */
{
if (!can_grow_low()) full_error();
return &(data[--low - base]);
}
inline void unsignedIChunk:: shrink_high ()
/* [<][>][^][v][top][bottom][index][help] */
{
if (empty()) empty_error();
--fence;
}
inline void unsignedIChunk:: shrink_low ()
/* [<][>][^][v][top][bottom][index][help] */
{
if (empty()) empty_error();
++low;
}
inline unsigned* unsignedIChunk::first_pointer() const
/* [<][>][^][v][top][bottom][index][help] */
{
return (low == fence)? 0 : &(data[low - base]);
}
inline unsigned* unsignedIChunk::last_pointer() const
/* [<][>][^][v][top][bottom][index][help] */
{
return (low == fence)? 0 : &(data[fence - base - 1]);
}
inline unsigned* unsignedIChunk::succ(unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return ((p+1) < &(data[low - base]) || (p+1) >= &(data[fence - base])) ?
0 : (p+1);
}
inline unsigned* unsignedIChunk::pred(unsigned* p) const
/* [<][>][^][v][top][bottom][index][help] */
{
return ((p-1) < &(data[low - base]) || (p-1) >= &(data[fence - base])) ?
0 : (p-1);
}
// generic Plex operations
inline unsignedPlex::unsignedPlex() {}
inline int unsignedPlex::chunk_size() const
/* [<][>][^][v][top][bottom][index][help] */
{
return csize;
}
inline int unsignedPlex::ecnef () const
/* [<][>][^][v][top][bottom][index][help] */
{
return lo - 1;
}
inline int unsignedPlex::fence () const
/* [<][>][^][v][top][bottom][index][help] */
{
return fnc;
}
inline int unsignedPlex::length () const
/* [<][>][^][v][top][bottom][index][help] */
{
return fnc - lo;
}
inline int unsignedPlex::empty () const
/* [<][>][^][v][top][bottom][index][help] */
{
return fnc == lo;
}
inline unsignedIChunk* unsignedPlex::tl() const
/* [<][>][^][v][top][bottom][index][help] */
{
return hd->prev();
}
inline int unsignedPlex::one_chunk() const
/* [<][>][^][v][top][bottom][index][help] */
{
return hd == hd->prev();
}
#endif