stl_deque.h

来自「ARM Linux Tool 各种代码包括MTD」· C头文件 代码 · 共 1,323 行 · 第 1/3 页

  size_type max_size() const { return size_type(-1); }
  bool empty() const { return _M_finish == _M_start; }

public:                         // Constructor, destructor.
  explicit deque(const allocator_type& __a = allocator_type()) 
    : _Base(__a, 0) {}
  deque(const deque& __x) : _Base(__x.get_allocator(), __x.size()) 
    { uninitialized_copy(__x.begin(), __x.end(), _M_start); }
  deque(size_type __n, const value_type& __value,
        const allocator_type& __a = allocator_type()) : _Base(__a, __n)
    { _M_fill_initialize(__value); }
  explicit deque(size_type __n) : _Base(allocator_type(), __n)
    { _M_fill_initialize(value_type()); }

  // Check whether it's an integral type.  If so, it's not an iterator.
  template <class _InputIterator>
  deque(_InputIterator __first, _InputIterator __last,
        const allocator_type& __a = allocator_type()) : _Base(__a) {
    typedef typename _Is_integer<_InputIterator>::_Integral _Integral;
    _M_initialize_dispatch(__first, __last, _Integral());
  }

  template <class _Integer>
  void _M_initialize_dispatch(_Integer __n, _Integer __x, __true_type) {
    _M_initialize_map(__n);
    _M_fill_initialize(__x);
  }

  template <class _InputIter>
  void _M_initialize_dispatch(_InputIter __first, _InputIter __last,
                              __false_type) {
    _M_range_initialize(__first, __last, __iterator_category(__first));
  }

  ~deque() { destroy(_M_start, _M_finish); }

  deque& operator= (const deque& __x) {
    const size_type __len = size();
    if (&__x != this) {
      if (__len >= __x.size())
        erase(copy(__x.begin(), __x.end(), _M_start), _M_finish);
      else {
        const_iterator __mid = __x.begin() + difference_type(__len);
        copy(__x.begin(), __mid, _M_start);
        insert(_M_finish, __mid, __x.end());
      }
    }
    return *this;
  }        

  void swap(deque& __x) {
    std::swap(_M_start, __x._M_start);
    std::swap(_M_finish, __x._M_finish);
    std::swap(_M_map, __x._M_map);
    std::swap(_M_map_size, __x._M_map_size);
  }

public: 
  // assign(), a generalized assignment member function.  Two
  // versions: one that takes a count, and one that takes a range.
  // The range version is a member template, so we dispatch on whether
  // or not the type is an integer.

  void _M_fill_assign(size_type __n, const _Tp& __val) {
    if (__n > size()) {
      fill(begin(), end(), __val);
      insert(end(), __n - size(), __val);
    }
    else {
      erase(begin() + __n, end());
      fill(begin(), end(), __val);
    }
  }

  void assign(size_type __n, const _Tp& __val) {
    _M_fill_assign(__n, __val);
  }

  template <class _InputIterator>
  void assign(_InputIterator __first, _InputIterator __last) {
    typedef typename _Is_integer<_InputIterator>::_Integral _Integral;
    _M_assign_dispatch(__first, __last, _Integral());
  }

private:                        // helper functions for assign() 

  template <class _Integer>
  void _M_assign_dispatch(_Integer __n, _Integer __val, __true_type)
    { _M_fill_assign((size_type) __n, (_Tp) __val); }

  template <class _InputIterator>
  void _M_assign_dispatch(_InputIterator __first, _InputIterator __last,
                          __false_type) {
    _M_assign_aux(__first, __last, __iterator_category(__first));
  }

  template <class _InputIterator>
  void _M_assign_aux(_InputIterator __first, _InputIterator __last,
                     input_iterator_tag);

  template <class _ForwardIterator>
  void _M_assign_aux(_ForwardIterator __first, _ForwardIterator __last,
                     forward_iterator_tag) {
    size_type __len = 0;
    distance(__first, __last, __len);
    if (__len > size()) {
      _ForwardIterator __mid = __first;
      advance(__mid, size());
      copy(__first, __mid, begin());
      insert(end(), __mid, __last);
    }
    else
      erase(copy(__first, __last, begin()), end());
  }

public:                         // push_* and pop_*
  
  void push_back(const value_type& __t) {
    if (_M_finish._M_cur != _M_finish._M_last - 1) {
      construct(_M_finish._M_cur, __t);
      ++_M_finish._M_cur;
    }
    else
      _M_push_back_aux(__t);
  }

  void push_back() {
    if (_M_finish._M_cur != _M_finish._M_last - 1) {
      construct(_M_finish._M_cur);
      ++_M_finish._M_cur;
    }
    else
      _M_push_back_aux();
  }

  void push_front(const value_type& __t) {
    if (_M_start._M_cur != _M_start._M_first) {
      construct(_M_start._M_cur - 1, __t);
      --_M_start._M_cur;
    }
    else
      _M_push_front_aux(__t);
  }

  void push_front() {
    if (_M_start._M_cur != _M_start._M_first) {
      construct(_M_start._M_cur - 1);
      --_M_start._M_cur;
    }
    else
      _M_push_front_aux();
  }


  void pop_back() {
    if (_M_finish._M_cur != _M_finish._M_first) {
      --_M_finish._M_cur;
      destroy(_M_finish._M_cur);
    }
    else
      _M_pop_back_aux();
  }

  void pop_front() {
    if (_M_start._M_cur != _M_start._M_last - 1) {
      destroy(_M_start._M_cur);
      ++_M_start._M_cur;
    }
    else 
      _M_pop_front_aux();
  }

public:                         // Insert

  iterator insert(iterator position, const value_type& __x) {
    if (position._M_cur == _M_start._M_cur) {
      push_front(__x);
      return _M_start;
    }
    else if (position._M_cur == _M_finish._M_cur) {
      push_back(__x);
      iterator __tmp = _M_finish;
      --__tmp;
      return __tmp;
    }
    else {
      return _M_insert_aux(position, __x);
    }
  }

  iterator insert(iterator __position)
    { return insert(__position, value_type()); }

  void insert(iterator __pos, size_type __n, const value_type& __x)
    { _M_fill_insert(__pos, __n, __x); }

  void _M_fill_insert(iterator __pos, size_type __n, const value_type& __x); 

  // Check whether it's an integral type.  If so, it's not an iterator.
  template <class _InputIterator>
  void insert(iterator __pos, _InputIterator __first, _InputIterator __last) {
    typedef typename _Is_integer<_InputIterator>::_Integral _Integral;
    _M_insert_dispatch(__pos, __first, __last, _Integral());
  }

  template <class _Integer>
  void _M_insert_dispatch(iterator __pos, _Integer __n, _Integer __x,
                          __true_type) {
    _M_fill_insert(__pos, (size_type) __n, (value_type) __x);
  }

  template <class _InputIterator>
  void _M_insert_dispatch(iterator __pos,
                          _InputIterator __first, _InputIterator __last,
                          __false_type) {
    insert(__pos, __first, __last, __iterator_category(__first));
  }

  void resize(size_type __new_size, const value_type& __x) {
    const size_type __len = size();
    if (__new_size < __len) 
      erase(_M_start + __new_size, _M_finish);
    else
      insert(_M_finish, __new_size - __len, __x);
  }

  void resize(size_type new_size) { resize(new_size, value_type()); }

public:                         // Erase
  iterator erase(iterator __pos) {
    iterator __next = __pos;
    ++__next;
    size_type __index = __pos - _M_start;
    if (__index < (size() >> 1)) {
      copy_backward(_M_start, __pos, __next);
      pop_front();
    }
    else {
      copy(__next, _M_finish, __pos);
      pop_back();
    }
    return _M_start + __index;
  }

  iterator erase(iterator __first, iterator __last);
  void clear(); 

protected:                        // Internal construction/destruction

  void _M_fill_initialize(const value_type& __value);

  template <class _InputIterator>
  void _M_range_initialize(_InputIterator __first, _InputIterator __last,
                        input_iterator_tag);

  template <class _ForwardIterator>
  void _M_range_initialize(_ForwardIterator __first, _ForwardIterator __last,
                        forward_iterator_tag);

protected:                        // Internal push_* and pop_*

  void _M_push_back_aux(const value_type&);
  void _M_push_back_aux();
  void _M_push_front_aux(const value_type&);
  void _M_push_front_aux();
  void _M_pop_back_aux();
  void _M_pop_front_aux();

protected:                        // Internal insert functions

  template <class _InputIterator>
  void insert(iterator __pos, _InputIterator __first, _InputIterator __last,
              input_iterator_tag);

  template <class _ForwardIterator>
  void insert(iterator __pos,
              _ForwardIterator __first, _ForwardIterator __last,
              forward_iterator_tag);

  iterator _M_insert_aux(iterator __pos, const value_type& __x);
  iterator _M_insert_aux(iterator __pos);
  void _M_insert_aux(iterator __pos, size_type __n, const value_type& __x);

  template <class _ForwardIterator>
  void _M_insert_aux(iterator __pos, 
                     _ForwardIterator __first, _ForwardIterator __last,
                     size_type __n);

  iterator _M_reserve_elements_at_front(size_type __n) {
    size_type __vacancies = _M_start._M_cur - _M_start._M_first;
    if (__n > __vacancies) 
      _M_new_elements_at_front(__n - __vacancies);
    return _M_start - difference_type(__n);
  }

  iterator _M_reserve_elements_at_back(size_type __n) {
    size_type __vacancies = (_M_finish._M_last - _M_finish._M_cur) - 1;
    if (__n > __vacancies)
      _M_new_elements_at_back(__n - __vacancies);
    return _M_finish + difference_type(__n);
  }

  void _M_new_elements_at_front(size_type __new_elements);
  void _M_new_elements_at_back(size_type __new_elements);

protected:                      // Allocation of _M_map and nodes

  // Makes sure the _M_map has space for new nodes.  Does not actually
  //  add the nodes.  Can invalidate _M_map pointers.  (And consequently, 
  //  deque iterators.)

  void _M_reserve_map_at_back (size_type __nodes_to_add = 1) {
    if (__nodes_to_add + 1 > _M_map_size - (_M_finish._M_node - _M_map))
      _M_reallocate_map(__nodes_to_add, false);
  }

  void _M_reserve_map_at_front (size_type __nodes_to_add = 1) {
    if (__nodes_to_add > size_type(_M_start._M_node - _M_map))
      _M_reallocate_map(__nodes_to_add, true);
  }

  void _M_reallocate_map(size_type __nodes_to_add, bool __add_at_front);
};

// Non-inline member functions

template <class _Tp, class _Alloc>
template <class _InputIter>
void deque<_Tp, _Alloc>
  ::_M_assign_aux(_InputIter __first, _InputIter __last, input_iterator_tag)
{
  iterator __cur = begin();
  for ( ; __first != __last && __cur != end(); ++__cur, ++__first)
    *__cur = *__first;
  if (__first == __last)
    erase(__cur, end());
  else
    insert(end(), __first, __last);
}

template <class _Tp, class _Alloc>
void deque<_Tp, _Alloc>::_M_fill_insert(iterator __pos,
                                        size_type __n, const value_type& __x)
{
  if (__pos._M_cur == _M_start._M_cur) {
    iterator __new_start = _M_reserve_elements_at_front(__n);
    __STL_TRY {
      uninitialized_fill(__new_start, _M_start, __x);
      _M_start = __new_start;
    }
    __STL_UNWIND(_M_destroy_nodes(__new_start._M_node, _M_start._M_node));
  }
  else if (__pos._M_cur == _M_finish._M_cur) {
    iterator __new_finish = _M_reserve_elements_at_back(__n);
    __STL_TRY {
      uninitialized_fill(_M_finish, __new_finish, __x);
      _M_finish = __new_finish;
    }
    __STL_UNWIND(_M_destroy_nodes(_M_finish._M_node + 1, 
                                  __new_finish._M_node + 1));    
  }
  else 
    _M_insert_aux(__pos, __n, __x);
}

template <class _Tp, class _Alloc>
typename deque<_Tp,_Alloc>::iterator 
deque<_Tp,_Alloc>::erase(iterator __first, iterator __last)
{
  if (__first == _M_start && __last == _M_finish) {
    clear();
    return _M_finish;
  }
  else {
    difference_type __n = __last - __first;
    difference_type __elems_before = __first - _M_start;
    if (static_cast<size_type>(__elems_before) < (size() - __n) / 2) {
      copy_backward(_M_start, __first, __last);
      iterator __new_start = _M_start + __n;
      destroy(_M_start, __new_start);
      _M_destroy_nodes(__new_start._M_node, _M_start._M_node);
      _M_start = __new_start;
    }
    else {
      copy(__last, _M_finish, __first);
      iterator __new_finish = _M_finish - __n;
      destroy(__new_finish, _M_finish);
      _M_destroy_nodes(__new_finish._M_node + 1, _M_finish._M_node + 1);
      _M_finish = __new_finish;
    }
    return _M_start + __elems_before;
  }
}

template <class _Tp, class _Alloc> 
void deque<_Tp,_Alloc>::clear()
{
  for (_Map_pointer __node = _M_start._M_node + 1;
       __node < _M_finish._M_node;
       ++__node) {
    destroy(*__node, *__node + _S_buffer_size());
    _M_deallocate_node(*__node);
  }

  if (_M_start._M_node != _M_finish._M_node) {
    destroy(_M_start._M_cur, _M_start._M_last);
    destroy(_M_finish._M_first, _M_finish._M_cur);
    _M_deallocate_node(_M_finish._M_first);
  }
  else
    destroy(_M_start._M_cur, _M_finish._M_cur);

  _M_finish = _M_start;
}

// Precondition: _M_start and _M_finish have already been initialized,
// but none of the deque's elements have yet been constructed.
template <class _Tp, class _Alloc>
void deque<_Tp,_Alloc>::_M_fill_initialize(const value_type& __value) {
  _Map_pointer __cur;
  __STL_TRY {
    for (__cur = _M_start._M_node; __cur < _M_finish._M_node; ++__cur)
      uninitialized_fill(*__cur, *__cur + _S_buffer_size(), __value);
    uninitialized_fill(_M_finish._M_first, _M_finish._M_cur, __value);
  }
  __STL_UNWIND(destroy(_M_start, iterator(*__cur, __cur)));
}

template <class _Tp, class _Alloc> template <class _InputIterator>
void deque<_Tp,_Alloc>::_M_range_initialize(_InputIterator __first,
                                            _InputIterator __last,
                                            input_iterator_tag)
{
  _M_initialize_map(0);
  __STL_TRY {
    for ( ; __first != __last; ++__first)
      push_back(*__first);
  }
  __STL_UNWIND(clear());
}