1// -*- C++ -*-
2
3// Copyright (C) 2005-2022 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 3, 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// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.
24
25// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26
27// Permission to use, copy, modify, sell, and distribute this software
28// is hereby granted without fee, provided that the above copyright
29// notice appears in all copies, and that both that copyright notice
30// and this permission notice appear in supporting documentation. None
31// of the above authors, nor IBM Haifa Research Laboratories, make any
32// representation about the suitability of this software for any
33// purpose. It is provided "as is" without express or implied
34// warranty.
35
36/**
37 * @file pat_trie_/erase_fn_imps.hpp
38 * Contains an implementation class for pat_trie.
39 */
40
41#ifdef PB_DS_CLASS_C_DEC
42
43PB_DS_CLASS_T_DEC
44inline bool
45PB_DS_CLASS_C_DEC::
46erase(key_const_reference r_key)
47{
48  node_pointer p_nd = find_imp(r_key);
49  if (p_nd == 0 || p_nd->m_type == i_node)
50    {
51      PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
52      return false;
53    }
54
55  _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
56  if (!synth_access_traits::equal_keys(PB_DS_V2F(reinterpret_cast<leaf_pointer>(p_nd)->value()), r_key))
57    {
58      PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
59      return false;
60    }
61
62  PB_DS_CHECK_KEY_EXISTS(r_key)
63  erase_leaf(static_cast<leaf_pointer>(p_nd));
64  PB_DS_ASSERT_VALID((*this))
65  return true;
66}
67
68PB_DS_CLASS_T_DEC
69void
70PB_DS_CLASS_C_DEC::
71erase_fixup(inode_pointer p_nd)
72{
73  _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) >= 1);
74  if (std::distance(p_nd->begin(), p_nd->end()) == 1)
75    {
76      node_pointer p_parent = p_nd->m_p_parent;
77      if (p_parent == m_p_head)
78	m_p_head->m_p_parent = *p_nd->begin();
79      else
80	{
81	  _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == i_node);
82	  node_pointer p_new_child = *p_nd->begin();
83
84	  typedef inode_pointer inode_ptr;
85	  inode_ptr p_internal = static_cast<inode_ptr>(p_parent);
86	  p_internal->replace_child(p_new_child, pref_begin(p_new_child),
87				    pref_end(p_new_child), this);
88	}
89      (*p_nd->begin())->m_p_parent = p_nd->m_p_parent;
90      p_nd->~inode();
91      s_inode_allocator.deallocate(p_nd, 1);
92
93      if (p_parent == m_p_head)
94	return;
95
96      _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == i_node);
97      p_nd = static_cast<inode_pointer>(p_parent);
98    }
99
100  while (true)
101    {
102      _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) > 1);
103      p_nd->update_prefixes(this);
104      apply_update(p_nd, (node_update*)this);
105      PB_DS_ASSERT_NODE_VALID(p_nd)
106      if (p_nd->m_p_parent->m_type == head_node)
107	return;
108
109      _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_parent->m_type == i_node);
110
111      p_nd = static_cast<inode_pointer>(p_nd->m_p_parent);
112    }
113}
114
115PB_DS_CLASS_T_DEC
116inline void
117PB_DS_CLASS_C_DEC::
118actual_erase_leaf(leaf_pointer p_l)
119{
120  _GLIBCXX_DEBUG_ASSERT(m_size > 0);
121  --m_size;
122  _GLIBCXX_DEBUG_ONLY(debug_base::erase_existing(PB_DS_V2F(p_l->value())));
123  p_l->~leaf();
124  s_leaf_allocator.deallocate(p_l, 1);
125}
126
127PB_DS_CLASS_T_DEC
128void
129PB_DS_CLASS_C_DEC::
130clear()
131{
132  if (!empty())
133    {
134      clear_imp(m_p_head->m_p_parent);
135      m_size = 0;
136      initialize();
137      _GLIBCXX_DEBUG_ONLY(debug_base::clear();)
138      PB_DS_ASSERT_VALID((*this))
139    }
140}
141
142PB_DS_CLASS_T_DEC
143void
144PB_DS_CLASS_C_DEC::
145clear_imp(node_pointer p_nd)
146{
147  if (p_nd->m_type == i_node)
148    {
149      _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == i_node);
150      for (typename inode::iterator it =
151	     static_cast<inode_pointer>(p_nd)->begin();
152	   it != static_cast<inode_pointer>(p_nd)->end();
153	   ++it)
154	{
155	  node_pointer p_child =* it;
156	  clear_imp(p_child);
157	}
158      s_inode_allocator.deallocate(static_cast<inode_pointer>(p_nd), 1);
159      return;
160    }
161
162  _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
163  static_cast<leaf_pointer>(p_nd)->~leaf();
164  s_leaf_allocator.deallocate(static_cast<leaf_pointer>(p_nd), 1);
165}
166
167PB_DS_CLASS_T_DEC
168inline typename PB_DS_CLASS_C_DEC::const_iterator
169PB_DS_CLASS_C_DEC::
170erase(const_iterator it)
171{
172  PB_DS_ASSERT_VALID((*this))
173
174  if (it == end())
175    return it;
176
177  const_iterator ret_it = it;
178  ++ret_it;
179  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
180  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
181  PB_DS_ASSERT_VALID((*this))
182  return ret_it;
183}
184
185#ifdef PB_DS_DATA_TRUE_INDICATOR
186PB_DS_CLASS_T_DEC
187inline typename PB_DS_CLASS_C_DEC::iterator
188PB_DS_CLASS_C_DEC::
189erase(iterator it)
190{
191  PB_DS_ASSERT_VALID((*this))
192
193  if (it == end())
194    return it;
195  iterator ret_it = it;
196  ++ret_it;
197  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
198  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
199  PB_DS_ASSERT_VALID((*this))
200  return ret_it;
201}
202#endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
203
204PB_DS_CLASS_T_DEC
205inline typename PB_DS_CLASS_C_DEC::const_reverse_iterator
206PB_DS_CLASS_C_DEC::
207erase(const_reverse_iterator it)
208{
209  PB_DS_ASSERT_VALID((*this))
210
211  if (it.m_p_nd == m_p_head)
212    return it;
213  const_reverse_iterator ret_it = it;
214  ++ret_it;
215
216  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
217  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
218  PB_DS_ASSERT_VALID((*this))
219  return ret_it;
220}
221
222#ifdef PB_DS_DATA_TRUE_INDICATOR
223PB_DS_CLASS_T_DEC
224inline typename PB_DS_CLASS_C_DEC::reverse_iterator
225PB_DS_CLASS_C_DEC::
226erase(reverse_iterator it)
227{
228  PB_DS_ASSERT_VALID((*this))
229
230  if (it.m_p_nd == m_p_head)
231    return it;
232  reverse_iterator ret_it = it;
233  ++ret_it;
234
235  _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
236  erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
237  PB_DS_ASSERT_VALID((*this))
238  return ret_it;
239}
240#endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
241
242PB_DS_CLASS_T_DEC
243template<typename Pred>
244inline typename PB_DS_CLASS_C_DEC::size_type
245PB_DS_CLASS_C_DEC::
246erase_if(Pred pred)
247{
248  size_type num_ersd = 0;
249  PB_DS_ASSERT_VALID((*this))
250
251  iterator it = begin();
252  while (it != end())
253    {
254      PB_DS_ASSERT_VALID((*this))
255      if (pred(*it))
256	{
257	  ++num_ersd;
258	  it = erase(it);
259	}
260      else
261	++it;
262    }
263
264  PB_DS_ASSERT_VALID((*this))
265  return num_ersd;
266}
267
268PB_DS_CLASS_T_DEC
269void
270PB_DS_CLASS_C_DEC::
271erase_leaf(leaf_pointer p_l)
272{
273  update_min_max_for_erased_leaf(p_l);
274  if (p_l->m_p_parent->m_type == head_node)
275    {
276      _GLIBCXX_DEBUG_ASSERT(size() == 1);
277      clear();
278      return;
279    }
280
281  _GLIBCXX_DEBUG_ASSERT(size() > 1);
282  _GLIBCXX_DEBUG_ASSERT(p_l->m_p_parent->m_type == i_node);
283
284  inode_pointer p_parent = static_cast<inode_pointer>(p_l->m_p_parent);
285
286  p_parent->remove_child(p_l);
287  erase_fixup(p_parent);
288  actual_erase_leaf(p_l);
289}
290
291PB_DS_CLASS_T_DEC
292void
293PB_DS_CLASS_C_DEC::
294update_min_max_for_erased_leaf(leaf_pointer p_l)
295{
296  if (m_size == 1)
297    {
298      m_p_head->m_p_min = m_p_head;
299      m_p_head->m_p_max = m_p_head;
300      return;
301    }
302
303  if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_min))
304    {
305      iterator it(p_l);
306      ++it;
307      m_p_head->m_p_min = it.m_p_nd;
308      return;
309    }
310
311  if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_max))
312    {
313      iterator it(p_l);
314      --it;
315      m_p_head->m_p_max = it.m_p_nd;
316    }
317}
318#endif
319