_deque.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_DEQUE_H
#define _STLP_INTERNAL_DEQUE_H

# 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_UNINITIALIZED_H
#  include <stl/_uninitialized.h>
# endif

# ifndef _STLP_RANGE_ERRORS_H
#  include <stl/_range_errors.h>
# endif

/* Class invariants:
 *  For any nonsingular iterator i:
 *    i.node is the address of an element in the map array.  The
 *      contents of i.node is a pointer to the beginning of a node.
 *    i.first == *(i.node) 
 *    i.last  == i.first + node_size
 *    i.cur is a pointer in the range [i.first, i.last).  NOTE:
 *      the implication of this is that i.cur is always a dereferenceable
 *      pointer, even if i is a past-the-end iterator.
 *  Start and Finish are always nonsingular iterators.  NOTE: this means
 *    that an empty deque must have one node, and that a deque
 *    with N elements, where N is the buffer size, must have two nodes.
 *  For every node other than start.node and finish.node, every element
 *    in the node is an initialized object.  If start.node == finish.node,
 *    then [start.cur, finish.cur) are initialized objects, and
 *    the elements outside that range are uninitialized storage.  Otherwise,
 *    [start.cur, start.last) and [finish.first, finish.cur) are initialized
 *    objects, and [start.first, start.cur) and [finish.cur, finish.last)
 *    are uninitialized storage.
 *  [map, map + map_size) is a valid, non-empty range.  
 *  [start.node, finish.node] is a valid range contained within 
 *    [map, map + map_size).  
 *  A pointer in the range [map, map + map_size) points to an allocated node
 *    if and only if the pointer is in the range [start.node, finish.node].
 */

# undef deque
# define deque __WORKAROUND_DBG_RENAME(deque)

_STLP_BEGIN_NAMESPACE

template <class _Tp>
struct _Deque_iterator_base {

  enum _Constants { 
    _blocksize = _MAX_BYTES, 
    __buffer_size = (sizeof(_Tp) < (size_t)_blocksize ?
   		    ( (size_t)_blocksize / sizeof(_Tp)) : size_t(1))
  };

  typedef random_access_iterator_tag iterator_category;

  typedef _Tp value_type;
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;

  typedef value_type** _Map_pointer;

  typedef _Deque_iterator_base< _Tp > _Self;

  value_type* _M_cur;
  value_type* _M_first;
  value_type* _M_last;
  _Map_pointer _M_node;

  _Deque_iterator_base(value_type* __x, _Map_pointer __y) 
    : _M_cur(__x), _M_first(*__y),
      _M_last(*__y + __buffer_size), _M_node(__y) {}
  _Deque_iterator_base() : _M_cur(0), _M_first(0), _M_last(0), _M_node(0) {}

  difference_type _M_subtract(const _Self& __x) const {
    return difference_type(__buffer_size) * (_M_node - __x._M_node - 1) +
      (_M_cur - _M_first) + (__x._M_last - __x._M_cur);
  }

  void _M_increment() {
    if (++_M_cur == _M_last) {
      _M_set_node(_M_node + 1);
      _M_cur = _M_first;
    }
  }

  void _M_decrement() {
    if (_M_cur == _M_first) {
      _M_set_node(_M_node - 1);
      _M_cur = _M_last;
    }
    --_M_cur;
  }

  void _M_advance(difference_type __n)
  {
    difference_type __offset = __n + (_M_cur - _M_first);
    if (__offset >= 0 && __offset < difference_type(__buffer_size))
      _M_cur += __n;
    else {
      difference_type __node_offset =
        __offset > 0 ? __offset / __buffer_size
                   : -difference_type((-__offset - 1) / __buffer_size) - 1;
      _M_set_node(_M_node + __node_offset);
      _M_cur = _M_first + 
        (__offset - __node_offset * difference_type(__buffer_size));
    }
  }

  void _M_set_node(_Map_pointer __new_node) {
    _M_last = (_M_first = *(_M_node = __new_node)) + difference_type(__buffer_size);
  }
};



template <class _Tp, class _Traits>
struct _Deque_iterator : public _Deque_iterator_base< _Tp> {

  typedef random_access_iterator_tag iterator_category;
  typedef _Tp value_type;
  typedef typename _Traits::reference  reference;
  typedef typename _Traits::pointer    pointer;
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;
  typedef value_type** _Map_pointer;

  typedef _Deque_iterator_base< _Tp > _Base;
  typedef _Deque_iterator<_Tp, _Traits> _Self;
  typedef _Deque_iterator<_Tp, _Nonconst_traits<_Tp> > _Nonconst_self;
  typedef _Deque_iterator<_Tp, _Const_traits<_Tp> > _Const_self;

  _Deque_iterator(value_type* __x, _Map_pointer __y) :
    _Deque_iterator_base<value_type>(__x,__y) {}

  _Deque_iterator() {}
  _Deque_iterator(const _Nonconst_self& __x) : 
    _Deque_iterator_base<value_type>(__x) {}

  reference operator*() const { 
      return *this->_M_cur; 
  }

  _STLP_DEFINE_ARROW_OPERATOR

  difference_type operator-(const _Self& __x) const { return this->_M_subtract(__x); }

  _Self& operator++() { this->_M_increment(); return *this; }
  _Self operator++(int)  {
    _Self __tmp = *this;
    ++*this;
    return __tmp;
  }

  _Self& operator--() { this->_M_decrement(); return *this; }
  _Self operator--(int) {
    _Self __tmp = *this;
    --*this;
    return __tmp;
  }

  _Self& operator+=(difference_type __n) { this->_M_advance(__n); return *this; }
  _Self operator+(difference_type __n) const
  {
    _Self __tmp = *this;
    return __tmp += __n;
  }

  _Self& operator-=(difference_type __n) { return *this += -__n; }
  _Self operator-(difference_type __n) const {
    _Self __tmp = *this;
    return __tmp -= __n;
  }

  reference operator[](difference_type __n) const { return *(*this + __n); }
};

template <class _Tp, class _Traits>
inline _Deque_iterator<_Tp, _Traits> _STLP_CALL
operator+(ptrdiff_t __n, const _Deque_iterator<_Tp, _Traits>& __x)
{
   return __x + __n;
}


#ifdef _STLP_USE_SEPARATE_RELOPS_NAMESPACE

template <class _Tp>
inline bool _STLP_CALL 
operator==(const _Deque_iterator_base<_Tp >& __x,
	   const _Deque_iterator_base<_Tp >& __y) { 
    return __x._M_cur == __y._M_cur; 
}

template <class _Tp>
inline bool _STLP_CALL 
operator < (const _Deque_iterator_base<_Tp >& __x,
	    const _Deque_iterator_base<_Tp >& __y) { 
  return (__x._M_node == __y._M_node) ? 
    (__x._M_cur < __y._M_cur) : (__x._M_node < __y._M_node);
}

template <class _Tp>
inline bool _STLP_CALL 
operator!=(const _Deque_iterator_base<_Tp >& __x,
	   const _Deque_iterator_base<_Tp >& __y) { 
    return __x._M_cur != __y._M_cur; 
}
template <class _Tp>
inline bool _STLP_CALL 
operator>(const _Deque_iterator_base<_Tp >& __x,
	  const _Deque_iterator_base<_Tp >& __y) { 
    return __y < __x;
}
template <class _Tp>
inline bool  _STLP_CALL operator>=(const _Deque_iterator_base<_Tp >& __x,
                                   const _Deque_iterator_base<_Tp >& __y) { 
    return !(__x < __y);
}
template <class _Tp>
inline bool  _STLP_CALL operator<=(const _Deque_iterator_base<_Tp >& __x,
                                   const _Deque_iterator_base<_Tp >& __y) { 
    return !(__y < __x);
}

# else

template <class _Tp, class _Traits1, class _Traits2>
inline bool  _STLP_CALL
operator==(const _Deque_iterator<_Tp, _Traits1 >& __x,
	   const _Deque_iterator<_Tp, _Traits2 >& __y) { 
    return __x._M_cur == __y._M_cur; 
}

template <class _Tp, class _Traits1, class _Traits2>
inline bool _STLP_CALL 
operator < (const _Deque_iterator<_Tp, _Traits1 >& __x,
	    const _Deque_iterator<_Tp, _Traits2 >& __y) { 
  return (__x._M_node == __y._M_node) ? 
    (__x._M_cur < __y._M_cur) : (__x._M_node < __y._M_node);
}

template <class _Tp>
inline bool _STLP_CALL 
operator!=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,
	   const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 
    return __x._M_cur != __y._M_cur; 
}
template <class _Tp>
inline bool _STLP_CALL 
operator>(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,
	  const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 
    return __y < __x;
}
template <class _Tp>
inline bool  _STLP_CALL
operator>=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,
           const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 
    return !(__x < __y);
}
template <class _Tp>
inline bool _STLP_CALL
operator<=(const _Deque_iterator<_Tp, _Nonconst_traits<_Tp> >& __x,
           const _Deque_iterator<_Tp, _Const_traits<_Tp> >& __y) { 
    return !(__y < __x);
}
# endif

# ifdef _STLP_USE_OLD_HP_ITERATOR_QUERIES
template <class _Tp, class _Traits> inline _Tp*  _STLP_CALL value_type(const _Deque_iterator<_Tp, _Traits  >&) { return (_Tp*)0; }
template <class _Tp, class _Traits> inline random_access_iterator_tag _STLP_CALL 
iterator_category(const _Deque_iterator<_Tp, _Traits  >&) { return random_access_iterator_tag(); }
template <class _Tp, class _Traits> inline ptrdiff_t* _STLP_CALL 
distance_type(const _Deque_iterator<_Tp, _Traits  >&) { return 0; }
#endif

// Deque base class.  It has two purposes.  First, its constructor
//  and destructor allocate (but don't initialize) storage.  This makes
//  exception safety easier.  Second, the base class encapsulates all of
//  the differences between SGI-style allocators and standard-conforming