_tree.h

MONA是为数不多的C++语言编写的一个很小的操作系统

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Copyright (c) 1996,1997
 * Silicon Graphics Computer Systems, Inc.
 *
 * Copyright (c) 1997
 * Moscow Center for SPARC Technology
 *
 * Copyright (c) 1999 
 * Boris Fomitchev
 *
 * This material is provided "as is", with absolutely no warranty expressed
 * or implied. Any use is at your own risk.
 *
 * Permission to use or copy this software for any purpose is hereby granted 
 * without fee, provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 *
 */

/* NOTE: This is an internal header file, included by other STL headers.
 *   You should not attempt to use it directly.
 */

#ifndef _STLP_INTERNAL_TREE_H
#define _STLP_INTERNAL_TREE_H

/*

Red-black tree class, designed for use in implementing STL
associative containers (set, multiset, map, and multimap). The
insertion and deletion algorithms are based on those in Cormen,
Leiserson, and Rivest, Introduction to Algorithms (MIT Press, 1990),
except that

(1) the header cell is maintained with links not only to the root
but also to the leftmost node of the tree, to enable constant time
begin(), and to the rightmost node of the tree, to enable linear time
performance when used with the generic set algorithms (set_union,
etc.);

(2) when a node being deleted has two children its successor node is
relinked into its place, rather than copied, so that the only
iterators invalidated are those referring to the deleted node.

*/

# ifndef _STLP_INTERNAL_ALGOBASE_H
#  include <stl/_algobase.h> 
# endif

# ifndef _STLP_INTERNAL_ALLOC_H
#  include <stl/_alloc.h> 
# endif

# ifndef _STLP_INTERNAL_ITERATOR_H
#  include <stl/_iterator.h> 
# endif

# ifndef _STLP_INTERNAL_CONSTRUCT_H
#  include <stl/_construct.h> 
# endif

# ifndef _STLP_INTERNAL_FUNCTION_H
#  include <stl/_function_base.h> 
# endif

#if defined ( _STLP_DEBUG)
#  define _Rb_tree __WORKAROUND_DBG_RENAME(Rb_tree)
#endif

_STLP_BEGIN_NAMESPACE

typedef bool _Rb_tree_Color_type;
//const _Rb_tree_Color_type _S_rb_tree_red = false;
//const _Rb_tree_Color_type _S_rb_tree_black = true;

#define _S_rb_tree_red false
#define _S_rb_tree_black true

struct _Rb_tree_node_base
{
  typedef _Rb_tree_Color_type _Color_type;
  typedef _Rb_tree_node_base* _Base_ptr;

  _Color_type _M_color; 
  _Base_ptr _M_parent;
  _Base_ptr _M_left;
  _Base_ptr _M_right;

  static _Base_ptr _STLP_CALL _S_minimum(_Base_ptr __x)
  {
    while (__x->_M_left != 0) __x = __x->_M_left;
    return __x;
  }

  static _Base_ptr _STLP_CALL _S_maximum(_Base_ptr __x)
  {
    while (__x->_M_right != 0) __x = __x->_M_right;
    return __x;
  }
};

template <class _Value> struct _Rb_tree_node : public _Rb_tree_node_base
{
  _Value _M_value_field;
  __TRIVIAL_STUFF(_Rb_tree_node)
};

struct _Rb_tree_base_iterator;

template <class _Dummy> class _Rb_global {
public:
  typedef _Rb_tree_node_base* _Base_ptr;
  // those used to be global functions 
  static void _STLP_CALL _Rebalance(_Rb_tree_node_base* __x, _Rb_tree_node_base*& __root);
  static _Rb_tree_node_base* _STLP_CALL _Rebalance_for_erase(_Rb_tree_node_base* __z,
                                                             _Rb_tree_node_base*& __root,
                                                             _Rb_tree_node_base*& __leftmost,
                                                             _Rb_tree_node_base*& __rightmost);
  // those are from _Rb_tree_base_iterator - moved here to reduce code bloat
  // moved here to reduce code bloat without templatizing _Rb_tree_base_iterator
  static _Rb_tree_node_base*  _STLP_CALL _M_increment(_Rb_tree_node_base*);
  static _Rb_tree_node_base*  _STLP_CALL _M_decrement(_Rb_tree_node_base*);
  static void _STLP_CALL _Rotate_left(_Rb_tree_node_base* __x, _Rb_tree_node_base*& __root);
  static void _STLP_CALL _Rotate_right(_Rb_tree_node_base* __x, _Rb_tree_node_base*& __root); 
};

# if defined (_STLP_USE_TEMPLATE_EXPORT) 
_STLP_EXPORT_TEMPLATE_CLASS _Rb_global<bool>;
# endif

typedef _Rb_global<bool> _Rb_global_inst;

struct _Rb_tree_base_iterator
{
  typedef _Rb_tree_node_base*        _Base_ptr;
  typedef bidirectional_iterator_tag iterator_category;
  typedef ptrdiff_t                  difference_type;
  _Base_ptr _M_node;
  bool operator==(const _Rb_tree_base_iterator& __y) const {
    return _M_node == __y._M_node;
  }
  bool operator!=(const _Rb_tree_base_iterator& __y) const {
    return _M_node != __y._M_node;
  }
};


template <class _Value, class _Traits> struct _Rb_tree_iterator : public _Rb_tree_base_iterator
{
  typedef _Value value_type;
  typedef typename _Traits::reference  reference;
  typedef typename _Traits::pointer    pointer;
  typedef _Rb_tree_iterator<_Value, _Traits> _Self;
  typedef _Rb_tree_node<_Value>* _Link_type;

  _Rb_tree_iterator() { _M_node = 0; }
  _Rb_tree_iterator(_Link_type __x) { _M_node = __x; }
  _Rb_tree_iterator(const _Rb_tree_iterator<_Value, 
                    _Nonconst_traits<_Value> >& __it) { _M_node = __it._M_node; }

  reference operator*() const { 
    return _Link_type(_M_node)->_M_value_field; 
  }
  
  _STLP_DEFINE_ARROW_OPERATOR

  _Self& operator++() { _M_node = _Rb_global_inst::_M_increment(_M_node); return *this; }
  _Self operator++(int) {
    _Self __tmp = *this;
    _M_node = _Rb_global_inst::_M_increment(_M_node);
    return __tmp;
  }
    
  _Self& operator--() { _M_node = _Rb_global_inst::_M_decrement(_M_node); return *this; }
  _Self operator--(int) {
    _Self __tmp = *this;
    _M_node = _Rb_global_inst::_M_decrement(_M_node);
    return __tmp;
  }
};

# ifdef _STLP_USE_OLD_HP_ITERATOR_QUERIES
template <class _Value, class _Traits> inline _Value* value_type(const _Rb_tree_iterator<_Value, _Traits>&) { return (_Value*)0; }
inline bidirectional_iterator_tag iterator_category(const _Rb_tree_base_iterator&) { return bidirectional_iterator_tag(); }
inline ptrdiff_t* distance_type(const _Rb_tree_base_iterator&) { return (ptrdiff_t*) 0; }
#endif /* _STLP_CLASS_PARTIAL_SPECIALIZATION */

// Base class to help EH

template <class _Tp, class _Alloc> struct _Rb_tree_base
{
  typedef _Rb_tree_node<_Tp> _Node;
  _STLP_FORCE_ALLOCATORS(_Tp, _Alloc)
  typedef typename _Alloc_traits<_Tp, _Alloc>::allocator_type allocator_type;

  _Rb_tree_base(const allocator_type& __a) : 
    _M_header(_STLP_CONVERT_ALLOCATOR(__a, _Node), (_Node*)0) { 
      _M_header._M_data = _M_header.allocate(1); 
  }
  ~_Rb_tree_base() { 
    _M_header.deallocate(_M_header._M_data,1); 
  }
  allocator_type get_allocator() const { 
    return _STLP_CONVERT_ALLOCATOR(_M_header, _Tp); 
  }
protected:
  typedef typename _Alloc_traits<_Node, _Alloc>::allocator_type _M_node_allocator_type;
  _STLP_alloc_proxy<_Node*, _Node, _M_node_allocator_type> _M_header;
};


template <class _Key, class _Value, class _KeyOfValue, class _Compare,
          _STLP_DEFAULT_ALLOCATOR_SELECT(_Value) > class _Rb_tree : public _Rb_tree_base<_Value, _Alloc> {
  typedef _Rb_tree_base<_Value, _Alloc> _Base;
protected:
  typedef _Rb_tree_node_base* _Base_ptr;
  typedef _Rb_tree_node<_Value> _Node;
  typedef _Rb_tree_Color_type _Color_type;
public:
  typedef _Key key_type;
  typedef _Value value_type;
  typedef value_type* pointer;
  typedef const value_type* const_pointer;
  typedef value_type& reference;
  typedef const value_type& const_reference;
  typedef _Rb_tree_node<_Value>* _Link_type;
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;
  typedef bidirectional_iterator_tag _Iterator_category;
  typedef typename _Base::allocator_type allocator_type;
  
protected:

  _Link_type _M_create_node(const value_type& __x)
  {
    _Link_type __tmp = this->_M_header.allocate(1);
    _STLP_TRY {
      _Construct(&__tmp->_M_value_field, __x);
    }
    _STLP_UNWIND(this->_M_header.deallocate(__tmp,1));
    return __tmp;
  }

  _Link_type _M_clone_node(_Link_type __x)
  {
    _Link_type __tmp = _M_create_node(__x->_M_value_field);
    __tmp->_M_color = __x->_M_color;
    __tmp->_M_left = 0;
    __tmp->_M_right = 0;
    return __tmp;
  }

protected:
  size_type _M_node_count; // keeps track of size of tree
  _Compare _M_key_compare;

  _Link_type& _M_root() const 
    { return (_Link_type&) this->_M_header._M_data->_M_parent; }
  _Link_type& _M_leftmost() const 
    { return (_Link_type&) this->_M_header._M_data->_M_left; }
  _Link_type& _M_rightmost() const 
    { return (_Link_type&) this->_M_header._M_data->_M_right; }

  static _Link_type& _STLP_CALL _S_left(_Link_type __x)
    { return (_Link_type&)(__x->_M_left); }
  static _Link_type& _STLP_CALL _S_right(_Link_type __x)
    { return (_Link_type&)(__x->_M_right); }
  static _Link_type& _STLP_CALL _S_parent(_Link_type __x)
    { return (_Link_type&)(__x->_M_parent); }
  static reference  _STLP_CALL _S_value(_Link_type __x)
    { return __x->_M_value_field; }
  static const _Key& _STLP_CALL _S_key(_Link_type __x)
    { return _KeyOfValue()(_S_value(__x)); }
  static _Color_type& _STLP_CALL _S_color(_Link_type __x)
    { return (_Color_type&)(__x->_M_color); }

  static _Link_type& _STLP_CALL _S_left(_Base_ptr __x)
    { return (_Link_type&)(__x->_M_left); }
  static _Link_type& _STLP_CALL _S_right(_Base_ptr __x)
    { return (_Link_type&)(__x->_M_right); }
  static _Link_type& _STLP_CALL _S_parent(_Base_ptr __x)
    { return (_Link_type&)(__x->_M_parent); }
  static reference  _STLP_CALL _S_value(_Base_ptr __x)
    { return ((_Link_type)__x)->_M_value_field; }
  static const _Key& _STLP_CALL _S_key(_Base_ptr __x)
    { return _KeyOfValue()(_S_value(_Link_type(__x)));} 
  static _Color_type& _STLP_CALL _S_color(_Base_ptr __x)
    { return (_Color_type&)(_Link_type(__x)->_M_color); }

  static _Link_type  _STLP_CALL _S_minimum(_Link_type __x) 
    { return (_Link_type)  _Rb_tree_node_base::_S_minimum(__x); }

  static _Link_type  _STLP_CALL _S_maximum(_Link_type __x)
    { return (_Link_type) _Rb_tree_node_base::_S_maximum(__x); }

public:
  typedef _Rb_tree_iterator<value_type, _Nonconst_traits<value_type> > iterator;
  typedef _Rb_tree_iterator<value_type, _Const_traits<value_type> > const_iterator;
  _STLP_DECLARE_BIDIRECTIONAL_REVERSE_ITERATORS;

private:
  iterator _M_insert(_Base_ptr __x, _Base_ptr __y, const value_type& __v, _Base_ptr __w = 0);
  _Link_type _M_copy(_Link_type __x, _Link_type __p);
  void _M_erase(_Link_type __x);