libstdc++-v3/include/ext/pb_ds/detail/pat_trie_/erase_fn_imps.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006, 2009, 2010, 2011 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 erase_fn_imps.hpp
  38  * Contains an implementation class for bin_search_tree_.
  39  */
  40
  41 PB_DS_CLASS_T_DEC
  42 inline bool
  43 PB_DS_CLASS_C_DEC::
  44 erase(const_key_reference r_key)
  45 {
  46   node_pointer p_nd = find_imp(r_key);
  47   if (p_nd == 0 || p_nd->m_type == pat_trie_internal_node_type)
  48     {
  49       PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
  50       return false;
  51     }
  52
  53   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == pat_trie_leaf_node_type);
  54   if (!synth_e_access_traits::equal_keys(PB_DS_V2F(reinterpret_cast<leaf_pointer>(p_nd)->value()), r_key))
  55     {
  56       PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
  57       return false;
  58     }
  59
  60   PB_DS_CHECK_KEY_EXISTS(r_key)
  61   erase_leaf(static_cast<leaf_pointer>(p_nd));
  62   PB_DS_ASSERT_VALID((*this))
  63   return true;
  64 }
  65
  66 PB_DS_CLASS_T_DEC
  67 void
  68 PB_DS_CLASS_C_DEC::
  69 erase_fixup(internal_node_pointer p_nd)
  70 {
  71   _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) >= 1);
  72   if (std::distance(p_nd->begin(), p_nd->end()) == 1)
  73     {
  74       node_pointer p_parent = p_nd->m_p_parent;
  75       if (p_parent == m_p_head)
  76         m_p_head->m_p_parent =* p_nd->begin();
  77       else
  78         {
  79           _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == pat_trie_internal_node_type);
  80           node_pointer p_new_child =* p_nd->begin();
  81           static_cast<internal_node_pointer>(p_parent)->replace_child(
  82                                                                       p_new_child,
  83                                                                       pref_begin(p_new_child),
  84                                                                       pref_end(p_new_child),
  85                                                                       this);
  86         }
  87       (*p_nd->begin())->m_p_parent = p_nd->m_p_parent;
  88       p_nd->~internal_node();
  89       s_internal_node_allocator.deallocate(p_nd, 1);
  90
  91       if (p_parent == m_p_head)
  92         return;
  93
  94       _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == pat_trie_internal_node_type);
  95       p_nd = static_cast<internal_node_pointer>(p_parent);
  96     }
  97
  98   while (true)
  99     {
 100       _GLIBCXX_DEBUG_ASSERT(std::distance(p_nd->begin(), p_nd->end()) > 1);
 101       p_nd->update_prefixes(this);
 102       apply_update(p_nd, (node_update* )this);
 103       PB_DS_ASSERT_NODE_VALID(p_nd)
 104       if (p_nd->m_p_parent->m_type == pat_trie_head_node_type)
 105         return;
 106
 107       _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_parent->m_type ==
 108                        pat_trie_internal_node_type);
 109
 110       p_nd = static_cast<internal_node_pointer>(p_nd->m_p_parent);
 111     }
 112 }
 113
 114 PB_DS_CLASS_T_DEC
 115 inline void
 116 PB_DS_CLASS_C_DEC::
 117 actual_erase_leaf(leaf_pointer p_l)
 118 {
 119   _GLIBCXX_DEBUG_ASSERT(m_size > 0);
 120   --m_size;
 121   _GLIBCXX_DEBUG_ONLY(erase_existing(PB_DS_V2F(p_l->value())));
 122   p_l->~leaf();
 123   s_leaf_allocator.deallocate(p_l, 1);
 124 }
 125
 126 PB_DS_CLASS_T_DEC
 127 void
 128 PB_DS_CLASS_C_DEC::
 129 clear()
 130 {
 131   PB_DS_ASSERT_VALID((*this))
 132   if (empty())
 133     return;
 134
 135   clear_imp(m_p_head->m_p_parent);
 136   m_size = 0;
 137   initialize();
 138   _GLIBCXX_DEBUG_ONLY(debug_base::clear();)
 139   PB_DS_ASSERT_VALID((*this))
 140 }
 141
 142 PB_DS_CLASS_T_DEC
 143 void
 144 PB_DS_CLASS_C_DEC::
 145 clear_imp(node_pointer p_nd)
 146 {
 147   if (p_nd->m_type == pat_trie_internal_node_type)
 148     {
 149       _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == pat_trie_internal_node_type);
 150       for (typename internal_node::iterator it =
 151              static_cast<internal_node_pointer>(p_nd)->begin();
 152            it != static_cast<internal_node_pointer>(p_nd)->end();
 153            ++it)
 154         {
 155           node_pointer p_child =* it;
 156           clear_imp(p_child);
 157         }
 158       s_internal_node_allocator.deallocate(static_cast<internal_node_pointer>(p_nd), 1);
 159       return;
 160     }
 161
 162   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == pat_trie_leaf_node_type);
 163   static_cast<leaf_pointer>(p_nd)->~leaf();
 164   s_leaf_allocator.deallocate(static_cast<leaf_pointer>(p_nd), 1);
 165 }
 166
 167 PB_DS_CLASS_T_DEC
 168 inline typename PB_DS_CLASS_C_DEC::const_iterator
 169 PB_DS_CLASS_C_DEC::
 170 erase(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 == pat_trie_leaf_node_type);
 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
 186 PB_DS_CLASS_T_DEC
 187 inline typename PB_DS_CLASS_C_DEC::iterator
 188 PB_DS_CLASS_C_DEC::
 189 erase(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 == pat_trie_leaf_node_type);
 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
 204 PB_DS_CLASS_T_DEC
 205 inline typename PB_DS_CLASS_C_DEC::const_reverse_iterator
 206 PB_DS_CLASS_C_DEC::
 207 erase(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 == pat_trie_leaf_node_type);
 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
 223 PB_DS_CLASS_T_DEC
 224 inline typename PB_DS_CLASS_C_DEC::reverse_iterator
 225 PB_DS_CLASS_C_DEC::
 226 erase(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 == pat_trie_leaf_node_type);
 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
 242 PB_DS_CLASS_T_DEC
 243 template<typename Pred>
 244 inline typename PB_DS_CLASS_C_DEC::size_type
 245 PB_DS_CLASS_C_DEC::
 246 erase_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
 268 PB_DS_CLASS_T_DEC
 269 void
 270 PB_DS_CLASS_C_DEC::
 271 erase_leaf(leaf_pointer p_l)
 272 {
 273   update_min_max_for_erased_leaf(p_l);
 274   if (p_l->m_p_parent->m_type == pat_trie_head_node_type)
 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 ==
 283                    pat_trie_internal_node_type);
 284
 285   internal_node_pointer p_parent =
 286     static_cast<internal_node_pointer>(p_l->m_p_parent);
 287
 288   p_parent->remove_child(p_l);
 289   erase_fixup(p_parent);
 290   actual_erase_leaf(p_l);
 291 }
 292
 293 PB_DS_CLASS_T_DEC
 294 void
 295 PB_DS_CLASS_C_DEC::
 296 update_min_max_for_erased_leaf(leaf_pointer p_l)
 297 {
 298   if (m_size == 1)
 299     {
 300       m_p_head->m_p_min = m_p_head;
 301       m_p_head->m_p_max = m_p_head;
 302       return;
 303     }
 304
 305   if (p_l == static_cast<const_leaf_pointer>(m_p_head->m_p_min))
 306     {
 307       iterator it(p_l);
 308       ++it;
 309       m_p_head->m_p_min = it.m_p_nd;
 310       return;
 311     }
 312
 313   if (p_l == static_cast<const_leaf_pointer>(m_p_head->m_p_max))
 314     {
 315       iterator it(p_l);
 316       --it;
 317       m_p_head->m_p_max = it.m_p_nd;
 318     }
 319 }