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

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2013 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 PB_DS_CLASS_T_DEC
  42 inline bool
  43 PB_DS_CLASS_C_DEC::
  44 erase(key_const_reference r_key)
  45 {
  46   node_pointer p_nd = find_imp(r_key);
  47   if (p_nd == 0 || p_nd->m_type == i_node)
  48     {
  49       PB_DS_CHECK_KEY_DOES_NOT_EXIST(r_key)
  50       return false;
  51     }
  52
  53   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
  54   if (!synth_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(inode_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 == i_node);
  80           node_pointer p_new_child = *p_nd->begin();
  81
  82           typedef inode_pointer inode_ptr;
  83           inode_ptr p_internal = static_cast<inode_ptr>(p_parent);
  84           p_internal->replace_child(p_new_child, pref_begin(p_new_child),
  85                                     pref_end(p_new_child), this);
  86         }
  87       (*p_nd->begin())->m_p_parent = p_nd->m_p_parent;
  88       p_nd->~inode();
  89       s_inode_allocator.deallocate(p_nd, 1);
  90
  91       if (p_parent == m_p_head)
  92         return;
  93
  94       _GLIBCXX_DEBUG_ASSERT(p_parent->m_type == i_node);
  95       p_nd = static_cast<inode_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 == head_node)
 105         return;
 106
 107       _GLIBCXX_DEBUG_ASSERT(p_nd->m_p_parent->m_type == i_node);
 108
 109       p_nd = static_cast<inode_pointer>(p_nd->m_p_parent);
 110     }
 111 }
 112
 113 PB_DS_CLASS_T_DEC
 114 inline void
 115 PB_DS_CLASS_C_DEC::
 116 actual_erase_leaf(leaf_pointer p_l)
 117 {
 118   _GLIBCXX_DEBUG_ASSERT(m_size > 0);
 119   --m_size;
 120   _GLIBCXX_DEBUG_ONLY(debug_base::erase_existing(PB_DS_V2F(p_l->value())));
 121   p_l->~leaf();
 122   s_leaf_allocator.deallocate(p_l, 1);
 123 }
 124
 125 PB_DS_CLASS_T_DEC
 126 void
 127 PB_DS_CLASS_C_DEC::
 128 clear()
 129 {
 130   if (!empty())
 131     {
 132       clear_imp(m_p_head->m_p_parent);
 133       m_size = 0;
 134       initialize();
 135       _GLIBCXX_DEBUG_ONLY(debug_base::clear();)
 136       PB_DS_ASSERT_VALID((*this))
 137     }
 138 }
 139
 140 PB_DS_CLASS_T_DEC
 141 void
 142 PB_DS_CLASS_C_DEC::
 143 clear_imp(node_pointer p_nd)
 144 {
 145   if (p_nd->m_type == i_node)
 146     {
 147       _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == i_node);
 148       for (typename inode::iterator it =
 149              static_cast<inode_pointer>(p_nd)->begin();
 150            it != static_cast<inode_pointer>(p_nd)->end();
 151            ++it)
 152         {
 153           node_pointer p_child =* it;
 154           clear_imp(p_child);
 155         }
 156       s_inode_allocator.deallocate(static_cast<inode_pointer>(p_nd), 1);
 157       return;
 158     }
 159
 160   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
 161   static_cast<leaf_pointer>(p_nd)->~leaf();
 162   s_leaf_allocator.deallocate(static_cast<leaf_pointer>(p_nd), 1);
 163 }
 164
 165 PB_DS_CLASS_T_DEC
 166 inline typename PB_DS_CLASS_C_DEC::const_iterator
 167 PB_DS_CLASS_C_DEC::
 168 erase(const_iterator it)
 169 {
 170   PB_DS_ASSERT_VALID((*this))
 171
 172   if (it == end())
 173     return it;
 174
 175   const_iterator ret_it = it;
 176   ++ret_it;
 177   _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
 178   erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
 179   PB_DS_ASSERT_VALID((*this))
 180   return ret_it;
 181 }
 182
 183 #ifdef PB_DS_DATA_TRUE_INDICATOR
 184 PB_DS_CLASS_T_DEC
 185 inline typename PB_DS_CLASS_C_DEC::iterator
 186 PB_DS_CLASS_C_DEC::
 187 erase(iterator it)
 188 {
 189   PB_DS_ASSERT_VALID((*this))
 190
 191   if (it == end())
 192     return it;
 193   iterator ret_it = it;
 194   ++ret_it;
 195   _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
 196   erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
 197   PB_DS_ASSERT_VALID((*this))
 198   return ret_it;
 199 }
 200 #endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
 201
 202 PB_DS_CLASS_T_DEC
 203 inline typename PB_DS_CLASS_C_DEC::const_reverse_iterator
 204 PB_DS_CLASS_C_DEC::
 205 erase(const_reverse_iterator it)
 206 {
 207   PB_DS_ASSERT_VALID((*this))
 208
 209   if (it.m_p_nd == m_p_head)
 210     return it;
 211   const_reverse_iterator ret_it = it;
 212   ++ret_it;
 213
 214   _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
 215   erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
 216   PB_DS_ASSERT_VALID((*this))
 217   return ret_it;
 218 }
 219
 220 #ifdef PB_DS_DATA_TRUE_INDICATOR
 221 PB_DS_CLASS_T_DEC
 222 inline typename PB_DS_CLASS_C_DEC::reverse_iterator
 223 PB_DS_CLASS_C_DEC::
 224 erase(reverse_iterator it)
 225 {
 226   PB_DS_ASSERT_VALID((*this))
 227
 228   if (it.m_p_nd == m_p_head)
 229     return it;
 230   reverse_iterator ret_it = it;
 231   ++ret_it;
 232
 233   _GLIBCXX_DEBUG_ASSERT(it.m_p_nd->m_type == leaf_node);
 234   erase_leaf(static_cast<leaf_pointer>(it.m_p_nd));
 235   PB_DS_ASSERT_VALID((*this))
 236   return ret_it;
 237 }
 238 #endif // #ifdef PB_DS_DATA_TRUE_INDICATOR
 239
 240 PB_DS_CLASS_T_DEC
 241 template<typename Pred>
 242 inline typename PB_DS_CLASS_C_DEC::size_type
 243 PB_DS_CLASS_C_DEC::
 244 erase_if(Pred pred)
 245 {
 246   size_type num_ersd = 0;
 247   PB_DS_ASSERT_VALID((*this))
 248
 249   iterator it = begin();
 250   while (it != end())
 251     {
 252       PB_DS_ASSERT_VALID((*this))
 253       if (pred(*it))
 254         {
 255           ++num_ersd;
 256           it = erase(it);
 257         }
 258       else
 259         ++it;
 260     }
 261
 262   PB_DS_ASSERT_VALID((*this))
 263   return num_ersd;
 264 }
 265
 266 PB_DS_CLASS_T_DEC
 267 void
 268 PB_DS_CLASS_C_DEC::
 269 erase_leaf(leaf_pointer p_l)
 270 {
 271   update_min_max_for_erased_leaf(p_l);
 272   if (p_l->m_p_parent->m_type == head_node)
 273     {
 274       _GLIBCXX_DEBUG_ASSERT(size() == 1);
 275       clear();
 276       return;
 277     }
 278
 279   _GLIBCXX_DEBUG_ASSERT(size() > 1);
 280   _GLIBCXX_DEBUG_ASSERT(p_l->m_p_parent->m_type == i_node);
 281
 282   inode_pointer p_parent = static_cast<inode_pointer>(p_l->m_p_parent);
 283
 284   p_parent->remove_child(p_l);
 285   erase_fixup(p_parent);
 286   actual_erase_leaf(p_l);
 287 }
 288
 289 PB_DS_CLASS_T_DEC
 290 void
 291 PB_DS_CLASS_C_DEC::
 292 update_min_max_for_erased_leaf(leaf_pointer p_l)
 293 {
 294   if (m_size == 1)
 295     {
 296       m_p_head->m_p_min = m_p_head;
 297       m_p_head->m_p_max = m_p_head;
 298       return;
 299     }
 300
 301   if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_min))
 302     {
 303       iterator it(p_l);
 304       ++it;
 305       m_p_head->m_p_min = it.m_p_nd;
 306       return;
 307     }
 308
 309   if (p_l == static_cast<leaf_const_pointer>(m_p_head->m_p_max))
 310     {
 311       iterator it(p_l);
 312       --it;
 313       m_p_head->m_p_max = it.m_p_nd;
 314     }
 315 }