libstdc++/stl/list.h

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

#ifndef __SGI_STL_LIST_H
#define __SGI_STL_LIST_H

#include <stddef.h>
#include <algobase.h>
#include <iterator.h>
#include <alloc.h>

template <class T>
struct __list_node {
  typedef void* void_pointer;
  void_pointer next;
  void_pointer prev;
  T data;
};

template<class T, class Ref>
struct __list_iterator {
  typedef __list_iterator<T, T&> iterator;
  typedef __list_iterator<T, const T&> const_iterator;
  typedef __list_iterator<T, Ref> self;

  typedef bidirectional_iterator_tag iterator_category;
  typedef T value_type;
  typedef value_type* pointer;
  typedef value_type& reference;
  typedef const value_type& const_reference;
  typedef __list_node<T>* link_type;
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;

  link_type node;

  __list_iterator(link_type x) : node(x) {}
  __list_iterator() {}
  __list_iterator(const iterator& x) : node(x.node) {}

  bool operator==(const self& x) const { return node == x.node; }
  bool operator!=(const self& x) const { return node != x.node; }
  Ref operator*() const { return (*node).data; }

  self& operator++() { 
    node = (link_type)((*node).next);
    return *this;
  }
  self operator++(int) { 
    self tmp = *this;
    ++*this;
    return tmp;
  }
  self& operator--() { 
    node = (link_type)((*node).prev);
    return *this;
  }
  self operator--(int) { 
    self tmp = *this;
    --*this;
    return tmp;
  }
};


template <class T, class Ref>
inline bidirectional_iterator_tag
iterator_category(const __list_iterator<T, Ref>&) {
  return bidirectional_iterator_tag();
}

template <class T, class Ref>
inline T*
value_type(const __list_iterator<T, Ref>&) {
  return 0;
}

template <class T, class Ref>
inline ptrdiff_t*
distance_type(const __list_iterator<T, Ref>&) {
  return 0;
}


template <class T, class Alloc = alloc>
class list {
protected:
    typedef void* void_pointer;
    typedef __list_node<T> list_node;
    typedef simple_alloc<list_node, Alloc> list_node_allocator;
public:      
    typedef T value_type;
    typedef value_type* pointer;
    typedef value_type& reference;
    typedef const value_type& const_reference;
    typedef list_node* link_type;
    typedef size_t size_type;
    typedef ptrdiff_t difference_type;

public:
    typedef __list_iterator<T, T&> iterator;
    typedef __list_iterator<T, const T&> const_iterator;

    typedef reverse_bidirectional_iterator<const_iterator, value_type,
                                           const_reference, difference_type>
            const_reverse_iterator;
    typedef reverse_bidirectional_iterator<iterator, value_type, reference,
                                           difference_type>
            reverse_iterator; 

protected:
    link_type get_node() { return list_node_allocator::allocate(); }
    void put_node(link_type p) { list_node_allocator::deallocate(p); }

    link_type create_node(const T& x) {
      link_type p = get_node();
#         ifdef __STL_USE_EXCEPTIONS
      try {
#         endif /* __STL_USE_EXCEPTIONS */
        construct(&p->data, x);
        return p;
#         ifdef __STL_USE_EXCEPTIONS
      }
      catch(...) {
        put_node(p);
        throw;
      }
#         endif /* __STL_USE_EXCEPTIONS */
    }
    void destroy_node(link_type p) {
      destroy(&p->data);
      put_node(p);
    }

protected:
    void empty_initialize() { 
      node = get_node();
      node->next = node;
      node->prev = node;
    }

    void fill_initialize(size_type n, const T& value) {
      empty_initialize();
#         ifdef __STL_USE_EXCEPTIONS
      try {
#         endif /* __STL_USE_EXCEPTIONS */
        insert(begin(), n, value);
#         ifdef __STL_USE_EXCEPTIONS
      }
      catch(...) {
        clear();
        put_node(node);
        throw;
      }
#         endif /* __STL_USE_EXCEPTIONS */
    }

#ifdef __STL_MEMBER_TEMPLATES
    template <class InputIterator>
    void range_initialize(InputIterator first, InputIterator last) {
      empty_initialize();
#         ifdef __STL_USE_EXCEPTIONS
      try {
#         endif /* __STL_USE_EXCEPTIONS */
        insert(begin(), first, last);
#         ifdef __STL_USE_EXCEPTIONS
      }
      catch(...) {
        clear();
        put_node(node);
        throw;
      }
#         endif /* __STL_USE_EXCEPTIONS */
    }
#else  /* __STL_MEMBER_TEMPLATES */
    void range_initialize(const T* first, const T* last) {
      empty_initialize();
#         ifdef __STL_USE_EXCEPTIONS
      try {
#         endif /* __STL_USE_EXCEPTIONS */
        insert(begin(), first, last);
#         ifdef __STL_USE_EXCEPTIONS
      }
      catch(...) {
        clear();
        put_node(node);
        throw;
      }
#         endif /* __STL_USE_EXCEPTIONS */
    }
    void range_initialize(const_iterator first, const_iterator last) {
      empty_initialize();
#         ifdef __STL_USE_EXCEPTIONS
      try {
#         endif /* __STL_USE_EXCEPTIONS */
        insert(begin(), first, last);
#         ifdef __STL_USE_EXCEPTIONS
      }
      catch(...) {
        clear();
        put_node(node);
        throw;
      }
#         endif /* __STL_USE_EXCEPTIONS */
    }  
#endif /* __STL_MEMBER_TEMPLATES */

protected:
    link_type node;

public:
    list() { empty_initialize(); }

    iterator begin() { return (link_type)((*node).next); }
    const_iterator begin() const { return (link_type)((*node).next); }
    iterator end() { return node; }
    const_iterator end() const { return node; }
    reverse_iterator rbegin() { return reverse_iterator(end()); }
    const_reverse_iterator rbegin() const { 
        return const_reverse_iterator(end()); 
    }
    reverse_iterator rend() { return reverse_iterator(begin()); }
    const_reverse_iterator rend() const { 
        return const_reverse_iterator(begin());
    } 
    bool empty() const { return node->next == node; }
    size_type size() const {
      size_type result = 0;
      distance(begin(), end(), result);
      return result;
    }
    size_type max_size() const { return size_type(-1); }
    reference front() { return *begin(); }
    const_reference front() const { return *begin(); }
    reference back() { return *(--end()); }
    const_reference back() const { return *(--end()); }
    void swap(list<T, Alloc>& x) { ::swap(node, x.node); }
    iterator insert(iterator position, const T& x) {
      link_type tmp = create_node(x);
      tmp->next = position.node;
      tmp->prev = position.node->prev;
      (link_type(position.node->prev))->next = tmp;
      position.node->prev = tmp;
      return tmp;
    }
    iterator insert(iterator position) { return insert(position, T()); }
#ifdef __STL_MEMBER_TEMPLATES
    template <class InputIterator>
    void insert(iterator position, InputIterator first, InputIterator last);
#else /* __STL_MEMBER_TEMPLATES */
    void insert(iterator position, const T* first, const T* last);
    void insert(iterator position,
                const_iterator first, const_iterator last);
#endif /* __STL_MEMBER_TEMPLATES */
    void insert(iterator pos, size_type n, const T& x);
    void insert(iterator pos, int n, const T& x) {
      insert(pos, (size_type)n, x);
    }
    void insert(iterator pos, long n, const T& x) {
      insert(pos, (size_type)n, x);
    }

    void push_front(const T& x) { insert(begin(), x); }
    void push_back(const T& x) { insert(end(), x); }
    void erase(iterator position) {
      (link_type(position.node->prev))->next = position.node->next;
      (link_type(position.node->next))->prev = position.node->prev;
      destroy_node(position.node);
    }
    void erase(iterator first, iterator last);
    void resize(size_type new_size, const T& x);
    void resize(size_type new_size) { resize(new_size, T()); }
    void clear();

    void pop_front() { erase(begin()); }
    void pop_back() { 
        iterator tmp = end();
        erase(--tmp);
    }
    list(size_type n, const T& value) { fill_initialize(n, value); }
    list(int n, const T& value) { fill_initialize(n, value); }
    list(long n, const T& value) { fill_initialize(n, value); }
    explicit list(size_type n) { fill_initialize(n, T()); }

#ifdef __STL_MEMBER_TEMPLATES
    template <class InputIterator>
    list(InputIterator first, InputIterator last) {
      range_initialize(first, last);
    }

#else /* __STL_MEMBER_TEMPLATES */
    list(const T* first, const T* last) { range_initialize(first, last); }
    list(const_iterator first, const_iterator last) {
      range_initialize(first, last);
    }
#endif /* __STL_MEMBER_TEMPLATES */
    list(const list<T, Alloc>& x) {
      range_initialize(x.begin(), x.end());
    }
    ~list() {
        clear();
	put_node(node);
    }
    list<T, Alloc>& operator=(const list<T, Alloc>& x);

protected:
    void transfer(iterator position, iterator first, iterator last) {
      if (position != last) {
	(*(link_type((*last.node).prev))).next = position.node;
	(*(link_type((*first.node).prev))).next = last.node;
	(*(link_type((*position.node).prev))).next = first.node;  
	link_type tmp = link_type((*position.node).prev);
	(*position.node).prev = (*last.node).prev;
	(*last.node).prev = (*first.node).prev; 
	(*first.node).prev = tmp;
      }
    }

public:
    void splice(iterator position, list& x) {
      if (!x.empty()) 
        transfer(position, x.begin(), x.end());
    }
    void splice(iterator position, list&, iterator i) {
      iterator j = i;
      ++j;
      if (position == i || position == j) return;
      transfer(position, i, j);
    }
    void splice(iterator position, list&, iterator first, iterator last) {
      if (first != last) 
        transfer(position, first, last);
    }
    void remove(const T& value);
    void unique();
    void merge(list& x);
    void reverse();
    void sort();

#ifdef __STL_MEMBER_TEMPLATES
    template <class Predicate> void remove_if(Predicate);
    template <class BinaryPredicate> void unique(BinaryPredicate);
    template <class StrictWeakOrdering> void merge(list&, StrictWeakOrdering);
    template <class StrictWeakOrdering> void sort(StrictWeakOrdering);
#endif /* __STL_MEMBER_TEMPLATES */

    friend bool operator== (const list& x, const list& y);
};

template <class T, class Alloc>
inline bool operator==(const list<T,Alloc>& x, const list<T,Alloc>& y) {
  typedef list<T,Alloc>::link_type link_type;
  link_type e1 = x.node;
  link_type e2 = y.node;
  link_type n1 = (link_type) e1->next;
  link_type n2 = (link_type) e2->next;
  for ( ; n1 != e1 && n2 != e2 ;
          n1 = (link_type) n1->next, n2 = (link_type) n2->next)
    if (n1->data != n2->data)
      return false;
  return n1 == e1 && n2 == e2;
}

template <class T, class Alloc>
inline bool operator<(const list<T, Alloc>& x, const list<T, Alloc>& y) {
    return lexicographical_compare(x.begin(), x.end(), y.begin(), y.end());
}

#ifdef __STL_MEMBER_TEMPLATES

template <class T, class Alloc> template <class InputIterator>
void list<T, Alloc>::insert(iterator position,
                            InputIterator first, InputIterator last) {
  for ( ; first != last; ++first)
    insert(position, *first);
}

#else /* __STL_MEMBER_TEMPLATES */

template <class T, class Alloc>
void list<T, Alloc>::insert(iterator position, const T* first, const T* last) {
  for ( ; first != last; ++first)
    insert(position, *first);
}

template <class T, class Alloc>
void list<T, Alloc>::insert(iterator position,
                            const_iterator first, const_iterator last) {
  for ( ; first != last; ++first)
    insert(position, *first);
}

#endif /* __STL_MEMBER_TEMPLATES */

template <class T, class Alloc>
void list<T, Alloc>::insert(iterator position, size_type n, const T& x) {
  for ( ; n > 0; --n)
    insert(position, x);
}

template <class T, class Alloc>
void list<T, Alloc>::erase(iterator first, iterator last) {
    while (first != last) erase(first++);
}

template <class T, class Alloc>
void list<T, Alloc>::resize(size_type new_size, const T& x)
{
  size_type len = size();
  if (new_size < len) {
    iterator f;
    if (new_size < len / 2) {
      f = begin();
      advance(f, new_size);
    }
    else {
      f = end();
      advance(f, difference_type(len) - difference_type(new_size));
    }
    erase(f, end());
  }
  else
    insert(end(), new_size - len, x);
}

template <class T, class Alloc> 
void list<T, Alloc>::clear()
{
  link_type cur = (link_type) node->next;
  while (cur != node) {
    link_type tmp = cur;
    cur = (link_type) cur->next;
    destroy_node(tmp);
  }
  node->next = node;
  node->prev = node;
}

template <class T, class Alloc>
list<T, Alloc>& list<T, Alloc>::operator=(const list<T, Alloc>& x) {
    if (this != &x) {
	iterator first1 = begin();
	iterator last1 = end();
	const_iterator first2 = x.begin();
	const_iterator last2 = x.end();
	while (first1 != last1 && first2 != last2) *first1++ = *first2++;
	if (first2 == last2)
	    erase(first1, last1);
	else
	    insert(last1, first2, last2);
    }
    return *this;
}

template <class T, class Alloc>
void list<T, Alloc>::remove(const T& value) {
  iterator first = begin();
  iterator last = end();
  while (first != last) {
    iterator next = first;
    ++next;
    if (*first == value) erase(first);
    first = next;
  }
}

template <class T, class Alloc>
void list<T, Alloc>::unique() {
  iterator first = begin();
  iterator last = end();
  if (first == last) return;
  iterator next = first;
  while (++next != last) {
    if (*first == *next)
      erase(next);
    else
      first = next;
    next = first;
  }
}

template <class T, class Alloc>
void list<T, Alloc>::merge(list<T, Alloc>& x) {
  iterator first1 = begin();
  iterator last1 = end();
  iterator first2 = x.begin();
  iterator last2 = x.end();
  while (first1 != last1 && first2 != last2)
    if (*first2 < *first1) {
      iterator next = first2;
      transfer(first1, first2, ++next);
      first2 = next;
    }
    else
      ++first1;
  if (first2 != last2) transfer(last1, first2, last2);
}

template <class T, class Alloc>
void list<T, Alloc>::reverse() {
  if (node->next == node || link_type(node->next)->next == node) return;
  iterator first = begin();
  ++first;
  while (first != end()) {
    iterator old = first;
    ++first;
    transfer(begin(), old, first);
  }
}    

template <class T, class Alloc>
void list<T, Alloc>::sort() {
  if (node->next == node || link_type(node->next)->next == node) return;
  list<T, Alloc> carry;
  list<T, Alloc> counter[64];
  int fill = 0;
  while (!empty()) {
    carry.splice(carry.begin(), *this, begin());
    int i = 0;
    while(i < fill && !counter[i].empty()) {
      counter[i].merge(carry);
      carry.swap(counter[i++]);
    }
    carry.swap(counter[i]);         
    if (i == fill) ++fill;
  } 

  for (int i = 1; i < fill; ++i) counter[i].merge(counter[i-1]);
  swap(counter[fill-1]);
}

#ifdef __STL_MEMBER_TEMPLATES

template <class T, class Alloc> template <class Predicate>
void list<T, Alloc>::remove_if(Predicate pred) {
  iterator first = begin();
  iterator last = end();
  while (first != last) {
    iterator next = first;
    ++next;
    if (pred(*first)) erase(first);
    first = next;
  }
}

template <class T, class Alloc> template <class BinaryPredicate>
void list<T, Alloc>::unique(BinaryPredicate binary_pred) {
  iterator first = begin();
  iterator last = end();
  if (first == last) return;
  iterator next = first;
  while (++next != last) {
    if (binary_pred(*first, *next))
      erase(next);
    else
      first = next;
    next = first;
  }
}

template <class T, class Alloc> template <class StrictWeakOrdering>
void list<T, Alloc>::merge(list<T, Alloc>& x, StrictWeakOrdering comp) {
  iterator first1 = begin();
  iterator last1 = end();
  iterator first2 = x.begin();
  iterator last2 = x.end();
  while (first1 != last1 && first2 != last2)
    if (comp(*first2, *first1)) {
      iterator next = first2;
      transfer(first1, first2, ++next);
      first2 = next;
    }
    else
      ++first1;
  if (first2 != last2) transfer(last1, first2, last2);
}

template <class T, class Alloc> template <class StrictWeakOrdering>
void list<T, Alloc>::sort(StrictWeakOrdering comp) {
  if (node->next == node || link_type(node->next)->next == node) return;
  list<T, Alloc> carry;
  list<T, Alloc> counter[64];
  int fill = 0;
  while (!empty()) {
    carry.splice(carry.begin(), *this, begin());
    int i = 0;
    while(i < fill && !counter[i].empty()) {
      counter[i].merge(carry, comp);
      carry.swap(counter[i++]);
    }
    carry.swap(counter[i]);         
    if (i == fill) ++fill;
  } 

  for (int i = 1; i < fill; ++i) counter[i].merge(counter[i-1], comp);
  swap(counter[fill-1]);
}

#endif /* __STL_MEMBER_TEMPLATES */

#endif /* __SGI_STL_LIST_H */