internal_node.hpp revision 169692 
1// -*- C++ -*-
2
3// Copyright (C) 2005, 2006 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the terms
7// of the GNU General Public License as published by the Free Software
8// Foundation; either version 2, or (at your option) any later
9// version.
10
11// This library is distributed in the hope that it will be useful, but
12// WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14// General Public License for more details.
15
16// You should have received a copy of the GNU General Public License
17// along with this library; see the file COPYING.  If not, write to
18// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
19// MA 02111-1307, USA.
20
21// As a special exception, you may use this file as part of a free
22// software library without restriction.  Specifically, if other files
23// instantiate templates or use macros or inline functions from this
24// file, or you compile this file and link it with other files to
25// produce an executable, this file does not by itself cause the
26// resulting executable to be covered by the GNU General Public
27// License.  This exception does not however invalidate any other
28// reasons why the executable file might be covered by the GNU General
29// Public License.
30
31// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
32
33// Permission to use, copy, modify, sell, and distribute this software
34// is hereby granted without fee, provided that the above copyright
35// notice appears in all copies, and that both that copyright notice
36// and this permission notice appear in supporting documentation. None
37// of the above authors, nor IBM Haifa Research Laboratories, make any
38// representation about the suitability of this software for any
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40// warranty.
41
42/**
43 * @file internal_node.hpp
44 * Contains an internal PB_DS_BASE_C_DEC for a patricia tree.
45 */
46
47#ifndef PB_DS_PAT_TRIE_INTERNAL_NODE_HPP
48#define PB_DS_PAT_TRIE_INTERNAL_NODE_HPP
49
50#include <debug/debug.h>
51
52namespace pb_ds
53{
54  namespace detail
55  {
56#define PB_DS_CLASS_T_DEC \
57    template<typename Type_Traits, typename E_Access_Traits,  \
58	     typename Metadata, typename Allocator>
59
60#define PB_DS_CLASS_C_DEC \
61    pat_trie_internal_node<Type_Traits, E_Access_Traits, Metadata, Allocator>
62
63#define PB_DS_BASE_C_DEC \
64    pat_trie_node_base<Type_Traits, E_Access_Traits, Metadata, Allocator>
65
66#define PB_DS_LEAF_C_DEC \
67    pat_trie_leaf<Type_Traits, E_Access_Traits, Metadata, Allocator>
68
69#define PB_DS_STATIC_ASSERT(UNIQUE, E) \
70    typedef static_assert_dumclass<sizeof(static_assert<(bool)(E)>)> UNIQUE##static_assert_type
71
72    template<typename Type_Traits,
73	     typename E_Access_Traits,
74	     typename Metadata,
75	     typename Allocator>
76    struct pat_trie_internal_node : public PB_DS_BASE_C_DEC
77    {
78    private:
79      typedef PB_DS_BASE_C_DEC 			base_type;
80      typedef Type_Traits 			type_traits;
81      typedef typename type_traits::value_type 	value_type;
82      typedef typename Allocator::size_type 	size_type;
83
84      typedef E_Access_Traits e_access_traits;
85      typedef typename e_access_traits::const_iterator const_e_iterator;
86      typedef typename Allocator::template rebind<e_access_traits>::other access_rebind;
87      typedef typename access_rebind::const_pointer const_e_access_traits_pointer;
88
89      typedef typename Allocator::template rebind<base_type>::other base_rebind;
90      typedef typename base_rebind::pointer node_pointer;
91      typedef typename base_rebind::const_pointer const_node_pointer;
92
93      typedef PB_DS_LEAF_C_DEC leaf;
94      typedef typename Allocator::template rebind<leaf>::other leaf_rebind;
95      typedef typename leaf_rebind::pointer leaf_pointer;
96      typedef typename leaf_rebind::const_pointer const_leaf_pointer;
97
98      typedef typename Allocator::template rebind<pat_trie_internal_node>::other internal_node_rebind;
99      typedef typename internal_node_rebind::pointer internal_node_pointer;
100      typedef typename internal_node_rebind::const_pointer const_internal_node_pointer;
101
102#ifdef _GLIBCXX_DEBUG
103      typedef typename base_type::subtree_debug_info subtree_debug_info;
104
105      virtual subtree_debug_info
106      assert_valid_imp(const_e_access_traits_pointer) const;
107#endif
108
109      inline size_type
110      get_pref_pos(const_e_iterator, const_e_iterator,
111		   const_e_access_traits_pointer) const;
112
113    public:
114      typedef typename Allocator::template rebind<node_pointer>::other node_pointer_rebind;
115      typedef typename node_pointer_rebind::pointer node_pointer_pointer;
116      typedef typename node_pointer_rebind::reference node_pointer_reference;
117
118      enum
119	{
120	  arr_size = E_Access_Traits::max_size + 1
121	};
122      PB_DS_STATIC_ASSERT(min_arr_size, arr_size >= 2);
123
124#include <ext/pb_ds/detail/pat_trie_/const_child_iterator.hpp>
125#include <ext/pb_ds/detail/pat_trie_/child_iterator.hpp>
126
127      pat_trie_internal_node(size_type, const const_e_iterator);
128
129      void
130      update_prefixes(const_e_access_traits_pointer);
131
132      const_iterator
133      begin() const;
134
135      iterator
136      begin();
137
138      const_iterator
139      end() const;
140
141      iterator
142      end();
143
144      inline node_pointer
145      get_child_node(const_e_iterator, const_e_iterator,
146		     const_e_access_traits_pointer);
147
148      inline const_node_pointer
149      get_child_node(const_e_iterator, const_e_iterator,
150		     const_e_access_traits_pointer) const;
151
152      inline iterator
153      get_child_it(const_e_iterator, const_e_iterator,
154		   const_e_access_traits_pointer);
155
156      inline node_pointer
157      get_lower_bound_child_node(const_e_iterator, const_e_iterator,
158				 size_type, const_e_access_traits_pointer);
159
160      inline node_pointer
161      add_child(node_pointer, const_e_iterator, const_e_iterator,
162		const_e_access_traits_pointer);
163
164      inline const_node_pointer
165      get_join_child(const_node_pointer, const_e_access_traits_pointer) const;
166
167      inline node_pointer
168      get_join_child(node_pointer, const_e_access_traits_pointer);
169
170      void
171      remove_child(node_pointer p_nd);
172
173      iterator
174      remove_child(iterator it);
175
176      void
177      replace_child(node_pointer, const_e_iterator, const_e_iterator,
178		    const_e_access_traits_pointer);
179
180      inline const_e_iterator
181      pref_b_it() const;
182
183      inline const_e_iterator
184      pref_e_it() const;
185
186      inline size_type
187      get_e_ind() const;
188
189      bool
190      should_be_mine(const_e_iterator, const_e_iterator, size_type,
191		     const_e_access_traits_pointer) const;
192
193      leaf_pointer
194      leftmost_descendant();
195
196      const_leaf_pointer
197      leftmost_descendant() const;
198
199      leaf_pointer
200      rightmost_descendant();
201
202      const_leaf_pointer
203      rightmost_descendant() const;
204
205#ifdef _GLIBCXX_DEBUG
206      size_type
207      e_ind() const;
208#endif
209
210    private:
211      pat_trie_internal_node(const pat_trie_internal_node&);
212
213      size_type
214      get_begin_pos() const;
215
216      const size_type m_e_ind;
217      const_e_iterator m_pref_b_it;
218      const_e_iterator m_pref_e_it;
219      node_pointer m_a_p_children[arr_size];
220      static leaf_rebind s_leaf_alloc;
221      static internal_node_rebind s_internal_node_alloc;
222    };
223
224    PB_DS_CLASS_T_DEC
225    typename PB_DS_CLASS_C_DEC::leaf_rebind
226    PB_DS_CLASS_C_DEC::s_leaf_alloc;
227
228    PB_DS_CLASS_T_DEC
229    typename PB_DS_CLASS_C_DEC::internal_node_rebind
230    PB_DS_CLASS_C_DEC::s_internal_node_alloc;
231
232    PB_DS_CLASS_T_DEC
233    inline typename PB_DS_CLASS_C_DEC::size_type
234    PB_DS_CLASS_C_DEC::
235    get_pref_pos(const_e_iterator b_it, const_e_iterator e_it,
236		 const_e_access_traits_pointer p_traits) const
237    {
238      if (static_cast<size_t>(std::distance(b_it, e_it)) <= m_e_ind)
239	return 0;
240      std::advance(b_it, m_e_ind);
241      return 1 + p_traits->e_pos(*b_it);
242    }
243
244    PB_DS_CLASS_T_DEC
245    PB_DS_CLASS_C_DEC::
246    pat_trie_internal_node(size_type len, const const_e_iterator it) :
247      PB_DS_BASE_C_DEC(pat_trie_internal_node_type),
248      m_e_ind(len), m_pref_b_it(it), m_pref_e_it(it)
249    {
250      std::advance(m_pref_e_it, m_e_ind);
251      std::fill(m_a_p_children, m_a_p_children + arr_size,
252		static_cast<node_pointer>(NULL));
253    }
254
255    PB_DS_CLASS_T_DEC
256    void
257    PB_DS_CLASS_C_DEC::
258    update_prefixes(const_e_access_traits_pointer p_traits)
259    {
260      node_pointer p_first = *begin();
261      if (p_first->m_type == pat_trie_leaf_node_type)
262	{
263	  const_leaf_pointer p = static_cast<const_leaf_pointer>(p_first);
264	  m_pref_b_it = p_traits->begin(e_access_traits::extract_key(p->value()));
265	}
266      else
267	{
268	  _GLIBCXX_DEBUG_ASSERT(p_first->m_type == pat_trie_internal_node_type);
269	  m_pref_b_it = static_cast<internal_node_pointer>(p_first)->pref_b_it();
270	}
271      m_pref_e_it = m_pref_b_it;
272      std::advance(m_pref_e_it, m_e_ind);
273    }
274
275    PB_DS_CLASS_T_DEC
276    typename PB_DS_CLASS_C_DEC::const_iterator
277    PB_DS_CLASS_C_DEC::
278    begin() const
279    {
280      typedef node_pointer_pointer pointer_type;
281      pointer_type p = const_cast<pointer_type>(m_a_p_children);
282      return const_iterator(p + get_begin_pos(), p + arr_size);
283    }
284
285    PB_DS_CLASS_T_DEC
286    typename PB_DS_CLASS_C_DEC::iterator
287    PB_DS_CLASS_C_DEC::
288    begin()
289    {
290      return iterator(m_a_p_children + get_begin_pos(),
291		      m_a_p_children + arr_size);
292    }
293
294    PB_DS_CLASS_T_DEC
295    typename PB_DS_CLASS_C_DEC::const_iterator
296    PB_DS_CLASS_C_DEC::
297    end() const
298    {
299      typedef node_pointer_pointer pointer_type;
300      pointer_type p = const_cast<pointer_type>(m_a_p_children) + arr_size;
301      return const_iterator(p, p);
302    }
303
304    PB_DS_CLASS_T_DEC
305    typename PB_DS_CLASS_C_DEC::iterator
306    PB_DS_CLASS_C_DEC::
307    end()
308    { return iterator(m_a_p_children + arr_size, m_a_p_children + arr_size); }
309
310    PB_DS_CLASS_T_DEC
311    inline typename PB_DS_CLASS_C_DEC::node_pointer
312    PB_DS_CLASS_C_DEC::
313    get_child_node(const_e_iterator b_it, const_e_iterator e_it,
314		   const_e_access_traits_pointer p_traits)
315    {
316      const size_type i = get_pref_pos(b_it, e_it, p_traits);
317      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
318      return m_a_p_children[i];
319    }
320
321    PB_DS_CLASS_T_DEC
322    inline typename PB_DS_CLASS_C_DEC::iterator
323    PB_DS_CLASS_C_DEC::
324    get_child_it(const_e_iterator b_it, const_e_iterator e_it,
325		 const_e_access_traits_pointer p_traits)
326    {
327      const size_type i = get_pref_pos(b_it, e_it, p_traits);
328      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
329      _GLIBCXX_DEBUG_ASSERT(m_a_p_children[i] != NULL);
330      return iterator(m_a_p_children + i, m_a_p_children + i);
331    }
332
333    PB_DS_CLASS_T_DEC
334    inline typename PB_DS_CLASS_C_DEC::const_node_pointer
335    PB_DS_CLASS_C_DEC::
336    get_child_node(const_e_iterator b_it, const_e_iterator e_it,
337		   const_e_access_traits_pointer p_traits) const
338    { return const_cast<node_pointer>(get_child_node(b_it, e_it, p_traits)); }
339
340    PB_DS_CLASS_T_DEC
341    typename PB_DS_CLASS_C_DEC::node_pointer
342    PB_DS_CLASS_C_DEC::
343    get_lower_bound_child_node(const_e_iterator b_it, const_e_iterator e_it,
344			       size_type checked_ind,
345			       const_e_access_traits_pointer p_traits)
346    {
347      if (!should_be_mine(b_it, e_it, checked_ind, p_traits))
348	{
349	  if (p_traits->cmp_prefixes(b_it, e_it, m_pref_b_it, m_pref_e_it, true))
350	    return leftmost_descendant();
351	  return rightmost_descendant();
352	}
353
354      size_type i = get_pref_pos(b_it, e_it, p_traits);
355      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
356
357      if (m_a_p_children[i] != NULL)
358	return m_a_p_children[i];
359
360      while (++i < arr_size)
361	if (m_a_p_children[i] != NULL)
362	  {
363	    if (m_a_p_children[i]->m_type == pat_trie_leaf_node_type)
364	      return m_a_p_children[i];
365
366	    _GLIBCXX_DEBUG_ASSERT(m_a_p_children[i]->m_type == pat_trie_internal_node_type);
367
368	    return static_cast<internal_node_pointer>(m_a_p_children[i])->leftmost_descendant();
369	  }
370
371      return rightmost_descendant();
372    }
373
374    PB_DS_CLASS_T_DEC
375    inline typename PB_DS_CLASS_C_DEC::node_pointer
376    PB_DS_CLASS_C_DEC::
377    add_child(node_pointer p_nd, const_e_iterator b_it, const_e_iterator e_it,
378	      const_e_access_traits_pointer p_traits)
379    {
380      const size_type i = get_pref_pos(b_it, e_it, p_traits);
381      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
382      if (m_a_p_children[i] == NULL)
383	{
384	  m_a_p_children[i] = p_nd;
385	  p_nd->m_p_parent = this;
386	  return p_nd;
387	}
388      return m_a_p_children[i];
389    }
390
391    PB_DS_CLASS_T_DEC
392    typename PB_DS_CLASS_C_DEC::const_node_pointer
393    PB_DS_CLASS_C_DEC::
394    get_join_child(const_node_pointer p_nd, const_e_access_traits_pointer p_traits) const
395    {
396      node_pointer p = const_cast<node_pointer>(p_nd);
397      return const_cast<internal_node_pointer>(this)->get_join_child(p, p_traits);
398    }
399
400    PB_DS_CLASS_T_DEC
401    typename PB_DS_CLASS_C_DEC::node_pointer
402    PB_DS_CLASS_C_DEC::
403    get_join_child(node_pointer p_nd, const_e_access_traits_pointer p_traits)
404    {
405      size_type i;
406      const_e_iterator b_it;
407      const_e_iterator e_it;
408      if (p_nd->m_type == pat_trie_leaf_node_type)
409	{
410	  typename Type_Traits::const_key_reference r_key =
411	    e_access_traits::extract_key(static_cast<const_leaf_pointer>(p_nd)->value());
412
413	  b_it = p_traits->begin(r_key);
414	  e_it = p_traits->end(r_key);
415	}
416      else
417	{
418	  b_it = static_cast<internal_node_pointer>(p_nd)->pref_b_it();
419	  e_it = static_cast<internal_node_pointer>(p_nd)->pref_e_it();
420	}
421      i = get_pref_pos(b_it, e_it, p_traits);
422      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
423      return m_a_p_children[i];
424    }
425
426    PB_DS_CLASS_T_DEC
427    void
428    PB_DS_CLASS_C_DEC::
429    remove_child(node_pointer p_nd)
430    {
431      size_type i = 0;
432      for (; i < arr_size; ++i)
433	if (m_a_p_children[i] == p_nd)
434	  {
435	    m_a_p_children[i] = NULL;
436	    return;
437	  }
438      _GLIBCXX_DEBUG_ASSERT(i != arr_size);
439    }
440
441    PB_DS_CLASS_T_DEC
442    typename PB_DS_CLASS_C_DEC::iterator
443    PB_DS_CLASS_C_DEC::
444    remove_child(iterator it)
445    {
446      iterator ret = it;
447      ++ret;
448      * it.m_p_p_cur = NULL;
449      return ret;
450    }
451
452    PB_DS_CLASS_T_DEC
453    void
454    PB_DS_CLASS_C_DEC::
455    replace_child(node_pointer p_nd, const_e_iterator b_it,
456		  const_e_iterator e_it,
457		  const_e_access_traits_pointer p_traits)
458    {
459      const size_type i = get_pref_pos(b_it, e_it, p_traits);
460      _GLIBCXX_DEBUG_ASSERT(i < arr_size);
461      m_a_p_children[i] = p_nd;
462      p_nd->m_p_parent = this;
463    }
464
465    PB_DS_CLASS_T_DEC
466    inline typename PB_DS_CLASS_C_DEC::const_e_iterator
467    PB_DS_CLASS_C_DEC::
468    pref_b_it() const
469    { return m_pref_b_it; }
470
471    PB_DS_CLASS_T_DEC
472    inline typename PB_DS_CLASS_C_DEC::const_e_iterator
473    PB_DS_CLASS_C_DEC::
474    pref_e_it() const
475    { return m_pref_e_it; }
476
477    PB_DS_CLASS_T_DEC
478    inline typename PB_DS_CLASS_C_DEC::size_type
479    PB_DS_CLASS_C_DEC::
480    get_e_ind() const
481    { return m_e_ind; }
482
483    PB_DS_CLASS_T_DEC
484    bool
485    PB_DS_CLASS_C_DEC::
486    should_be_mine(const_e_iterator b_it, const_e_iterator e_it,
487		   size_type checked_ind,
488		   const_e_access_traits_pointer p_traits) const
489    {
490      if (m_e_ind == 0)
491	return true;
492
493      const size_type num_es = std::distance(b_it, e_it);
494      if (num_es < m_e_ind)
495	return false;
496
497      const_e_iterator key_b_it = b_it;
498      std::advance(key_b_it, checked_ind);
499      const_e_iterator key_e_it = b_it;
500      std::advance(key_e_it, m_e_ind);
501
502      const_e_iterator value_b_it = m_pref_b_it;
503      std::advance(value_b_it, checked_ind);
504      const_e_iterator value_e_it = m_pref_b_it;
505      std::advance(value_e_it, m_e_ind);
506
507      return p_traits->equal_prefixes(key_b_it, key_e_it, value_b_it,
508				      value_e_it);
509    }
510
511    PB_DS_CLASS_T_DEC
512    typename PB_DS_CLASS_C_DEC::leaf_pointer
513    PB_DS_CLASS_C_DEC::
514    leftmost_descendant()
515    {
516      node_pointer p_pot =* begin();
517      if (p_pot->m_type == pat_trie_leaf_node_type)
518	return (static_cast<leaf_pointer>(p_pot));
519      _GLIBCXX_DEBUG_ASSERT(p_pot->m_type == pat_trie_internal_node_type);
520      return static_cast<internal_node_pointer>(p_pot)->leftmost_descendant();
521    }
522
523    PB_DS_CLASS_T_DEC
524    typename PB_DS_CLASS_C_DEC::const_leaf_pointer
525    PB_DS_CLASS_C_DEC::
526    leftmost_descendant() const
527    {
528      return const_cast<internal_node_pointer>(this)->leftmost_descendant();
529    }
530
531    PB_DS_CLASS_T_DEC
532    typename PB_DS_CLASS_C_DEC::leaf_pointer
533    PB_DS_CLASS_C_DEC::
534    rightmost_descendant()
535    {
536      const size_type num_children = std::distance(begin(), end());
537      _GLIBCXX_DEBUG_ASSERT(num_children >= 2);
538
539      iterator it = begin();
540      std::advance(it, num_children - 1);
541      node_pointer p_pot =* it;
542      if (p_pot->m_type == pat_trie_leaf_node_type)
543	return static_cast<leaf_pointer>(p_pot);
544      _GLIBCXX_DEBUG_ASSERT(p_pot->m_type == pat_trie_internal_node_type);
545      return static_cast<internal_node_pointer>(p_pot)->rightmost_descendant();
546    }
547
548    PB_DS_CLASS_T_DEC
549    typename PB_DS_CLASS_C_DEC::const_leaf_pointer
550    PB_DS_CLASS_C_DEC::
551    rightmost_descendant() const
552    {
553      return const_cast<internal_node_pointer>(this)->rightmost_descendant();
554    }
555
556#ifdef _GLIBCXX_DEBUG
557    PB_DS_CLASS_T_DEC
558    typename PB_DS_CLASS_C_DEC::size_type
559    PB_DS_CLASS_C_DEC::
560    e_ind() const
561    { return m_e_ind; }
562#endif
563
564    PB_DS_CLASS_T_DEC
565    typename PB_DS_CLASS_C_DEC::size_type
566    PB_DS_CLASS_C_DEC::
567    get_begin_pos() const
568    {
569      size_type i;
570      for (i = 0; i < arr_size && m_a_p_children[i] == NULL; ++i)
571	;
572      return i;
573    }
574
575#ifdef _GLIBCXX_DEBUG
576    PB_DS_CLASS_T_DEC
577    typename PB_DS_CLASS_C_DEC::subtree_debug_info
578    PB_DS_CLASS_C_DEC::
579    assert_valid_imp(const_e_access_traits_pointer p_traits) const
580    {
581      _GLIBCXX_DEBUG_ASSERT(base_type::m_type == pat_trie_internal_node_type);
582      _GLIBCXX_DEBUG_ASSERT(static_cast<size_type>(std::distance(pref_b_it(), pref_e_it())) == m_e_ind);
583      _GLIBCXX_DEBUG_ASSERT(std::distance(begin(), end()) >= 2);
584
585      for (typename pat_trie_internal_node::const_iterator it = begin();
586	   it != end(); ++it)
587	{
588	  const_node_pointer p_nd =* it;
589	  _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_parent == this);
590	  subtree_debug_info child_ret = p_nd->assert_valid_imp(p_traits);
591
592	  _GLIBCXX_DEBUG_ASSERT(static_cast<size_type>(std::distance(child_ret.first, child_ret.second)) >= m_e_ind);
593	  _GLIBCXX_DEBUG_ASSERT(should_be_mine(child_ret.first, child_ret.second, 0, p_traits));
594	  _GLIBCXX_DEBUG_ASSERT(get_pref_pos(child_ret.first, child_ret.second, p_traits) == static_cast<size_type>(it.m_p_p_cur - m_a_p_children));
595	}
596      return std::make_pair(pref_b_it(), pref_e_it());
597    }
598#endif
599
600#undef PB_DS_CLASS_T_DEC
601#undef PB_DS_CLASS_C_DEC
602#undef PB_DS_BASE_C_DEC
603#undef PB_DS_LEAF_C_DEC
604#undef PB_DS_STATIC_ASSERT
605
606  } // namespace detail
607} // namespace pb_ds
608
609#endif
610