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

   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
  39 // purpose. It is provided "as is" without express or implied
  40 // warranty.
  41
  42 /**
  43  * @file split_fn_imps.hpp
  44  * Contains an implementation class for bin_search_tree_.
  45  */
  46
  47 PB_DS_CLASS_T_DEC
  48 void
  49 PB_DS_CLASS_C_DEC::
  50 split(const_key_reference r_key, PB_DS_CLASS_C_DEC& other)
  51 {
  52   _GLIBCXX_DEBUG_ONLY(assert_valid(););
  53   _GLIBCXX_DEBUG_ONLY(other.assert_valid(););
  54   split_join_branch_bag bag;
  55   leaf_pointer p_split_lf = split_prep(r_key, other, bag);
  56   if (p_split_lf == NULL)
  57     {
  58       _GLIBCXX_DEBUG_ASSERT(bag.empty());
  59       _GLIBCXX_DEBUG_ONLY(assert_valid();)
  60       _GLIBCXX_DEBUG_ONLY(other.assert_valid();)
  61       return;
  62     }
  63
  64   _GLIBCXX_DEBUG_ASSERT(!bag.empty());
  65   other.clear();
  66   m_p_head->m_p_parent = rec_split(m_p_head->m_p_parent,
  67                                    pref_begin(p_split_lf),
  68                                    pref_end(p_split_lf),
  69                                    other,
  70                                    bag);
  71
  72   m_p_head->m_p_parent->m_p_parent = m_p_head;
  73
  74   other.m_p_head->m_p_max = m_p_head->m_p_max;
  75   m_p_head->m_p_max = rightmost_descendant(m_p_head->m_p_parent);
  76   other.m_p_head->m_p_min =
  77     other.leftmost_descendant(other.m_p_head->m_p_parent);
  78
  79   other.m_size = std::distance(other.PB_DS_CLASS_C_DEC::begin(),
  80                                other.PB_DS_CLASS_C_DEC::end());
  81   m_size -= other.m_size;
  82   _GLIBCXX_DEBUG_ONLY(assert_valid(););
  83   _GLIBCXX_DEBUG_ONLY(other.assert_valid(););
  84 }
  85
  86 PB_DS_CLASS_T_DEC
  87 typename PB_DS_CLASS_C_DEC::leaf_pointer
  88 PB_DS_CLASS_C_DEC::
  89 split_prep(const_key_reference r_key, PB_DS_CLASS_C_DEC& other, split_join_branch_bag& r_bag)
  90 {
  91   _GLIBCXX_DEBUG_ASSERT(r_bag.empty());
  92   if (m_size == 0)
  93     {
  94       other.clear();
  95       _GLIBCXX_DEBUG_ONLY(assert_valid(););
  96       _GLIBCXX_DEBUG_ONLY(other.assert_valid(););
  97       return (NULL);
  98     }
  99
 100   if (synth_e_access_traits::cmp_keys(r_key,
 101                                       PB_DS_V2F(static_cast<const_leaf_pointer>(m_p_head->m_p_min)->value())))
 102     {
 103       other.clear();
 104       value_swap(other);
 105       _GLIBCXX_DEBUG_ONLY(assert_valid(););
 106       _GLIBCXX_DEBUG_ONLY(other.assert_valid(););
 107       return (NULL);
 108     }
 109
 110   if (!synth_e_access_traits::cmp_keys(r_key,
 111                                        PB_DS_V2F(static_cast<const_leaf_pointer>(m_p_head->m_p_max)->value())))
 112     {
 113       _GLIBCXX_DEBUG_ONLY(assert_valid(););
 114       _GLIBCXX_DEBUG_ONLY(other.assert_valid(););
 115       return (NULL);
 116     }
 117
 118   iterator it = lower_bound(r_key);
 119
 120   if (!synth_e_access_traits::equal_keys(PB_DS_V2F(*it), r_key))
 121     --it;
 122
 123   node_pointer p_nd = it.m_p_nd;
 124   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == pat_trie_leaf_node_type);
 125   leaf_pointer p_ret_l = static_cast<leaf_pointer>(p_nd);
 126   while (p_nd->m_type != pat_trie_head_node_type)
 127     {
 128       r_bag.add_branch();
 129       p_nd = p_nd->m_p_parent;
 130     }
 131   _GLIBCXX_DEBUG_ONLY(debug_base::split(r_key,(synth_e_access_traits& )(*this), other);)
 132
 133   return (p_ret_l);
 134 }
 135
 136 PB_DS_CLASS_T_DEC
 137 typename PB_DS_CLASS_C_DEC::node_pointer
 138 PB_DS_CLASS_C_DEC::
 139 rec_split(node_pointer p_nd, const_e_iterator b_it, const_e_iterator e_it, PB_DS_CLASS_C_DEC& other, split_join_branch_bag& r_bag)
 140 {
 141   if (p_nd->m_type == pat_trie_leaf_node_type)
 142     {
 143       _GLIBCXX_DEBUG_ASSERT(other.m_p_head->m_p_parent == NULL);
 144       return (p_nd);
 145     }
 146
 147   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == pat_trie_internal_node_type);
 148   internal_node_pointer p_internal_nd = static_cast<internal_node_pointer>(p_nd);
 149
 150   node_pointer p_child_ret = rec_split(p_internal_nd->get_child_node(b_it, e_it, this), b_it, e_it, other, r_bag);
 151
 152   _GLIBCXX_DEBUG_ONLY(p_child_ret->assert_valid(this);)
 153   p_internal_nd->replace_child(p_child_ret, b_it, e_it, this);
 154   apply_update(p_internal_nd, (node_update* )this);
 155
 156   typename internal_node::iterator child_it  =
 157     p_internal_nd->get_child_it(b_it, e_it, this);
 158
 159   const size_type lhs_num_children =
 160     std::distance(p_internal_nd->begin(), child_it) + 1;
 161
 162   _GLIBCXX_DEBUG_ASSERT(lhs_num_children > 0);
 163
 164   size_type rhs_num_children =
 165     std::distance(p_internal_nd->begin(), p_internal_nd->end()) -
 166     lhs_num_children;
 167
 168   if (rhs_num_children == 0)
 169     {
 170       apply_update(p_internal_nd, (node_update* )this);
 171       return (p_internal_nd);
 172     }
 173
 174   ++child_it;
 175   other.split_insert_branch(p_internal_nd->get_e_ind(),
 176                             b_it, child_it, rhs_num_children, r_bag);
 177
 178   child_it = p_internal_nd->get_child_it(b_it, e_it, this);
 179   ++child_it;
 180   while (rhs_num_children != 0)
 181     {
 182       child_it = p_internal_nd->remove_child(child_it);
 183       --rhs_num_children;
 184     }
 185
 186   apply_update(p_internal_nd, (node_update* )this);
 187   _GLIBCXX_DEBUG_ASSERT(std::distance(p_internal_nd->begin(),
 188                                       p_internal_nd->end()) >= 1);
 189
 190   if (std::distance(p_internal_nd->begin(), p_internal_nd->end()) > 1)
 191     {
 192       p_internal_nd->update_prefixes(this);
 193       _GLIBCXX_DEBUG_ONLY(p_internal_nd->assert_valid(this);)
 194       apply_update(p_internal_nd, (node_update* )this);
 195       return (p_internal_nd);
 196     }
 197
 198   node_pointer p_ret =* p_internal_nd->begin();
 199   p_internal_nd->~internal_node();
 200   s_internal_node_allocator.deallocate(p_internal_nd, 1);
 201   apply_update(p_ret, (node_update* )this);
 202   return (p_ret);
 203 }
 204
 205 PB_DS_CLASS_T_DEC
 206 void
 207 PB_DS_CLASS_C_DEC::
 208 split_insert_branch(size_type e_ind, const_e_iterator b_it, typename internal_node::iterator child_b_it, size_type num_children, split_join_branch_bag& r_bag)
 209 {
 210 #ifdef _GLIBCXX_DEBUG
 211   if (m_p_head->m_p_parent != NULL)
 212     m_p_head->m_p_parent->assert_valid(this);
 213 #endif
 214
 215   const size_type total_num_children =((m_p_head->m_p_parent == NULL)? 0 : 1) + num_children;
 216
 217   if (total_num_children == 0)
 218     {
 219       _GLIBCXX_DEBUG_ASSERT(m_p_head->m_p_parent == NULL);
 220       return;
 221     }
 222
 223   if (total_num_children == 1)
 224     {
 225       if (m_p_head->m_p_parent != NULL)
 226         {
 227           _GLIBCXX_DEBUG_ONLY(m_p_head->m_p_parent->assert_valid(this);)
 228           return;
 229         }
 230
 231       _GLIBCXX_DEBUG_ASSERT(m_p_head->m_p_parent == NULL);
 232       m_p_head->m_p_parent =* child_b_it;
 233       m_p_head->m_p_parent->m_p_parent = m_p_head;
 234       apply_update(m_p_head->m_p_parent, (node_update* )this);
 235       _GLIBCXX_DEBUG_ONLY(m_p_head->m_p_parent->assert_valid(this);)
 236       return;
 237     }
 238
 239   _GLIBCXX_DEBUG_ASSERT(total_num_children > 1);
 240   internal_node_pointer p_new_root = r_bag.get_branch();
 241   new (p_new_root) internal_node(e_ind, b_it);
 242   size_type num_inserted = 0;
 243   while (num_inserted++ < num_children)
 244     {
 245       _GLIBCXX_DEBUG_ONLY((*child_b_it)->assert_valid(this);)
 246         p_new_root->add_child(*child_b_it, pref_begin(*child_b_it),
 247                               pref_end(*child_b_it), this);
 248       ++child_b_it;
 249     }
 250
 251   if (m_p_head->m_p_parent != NULL)
 252     p_new_root->add_child(m_p_head->m_p_parent,
 253                           pref_begin(m_p_head->m_p_parent),
 254                           pref_end(m_p_head->m_p_parent), this);
 255
 256   m_p_head->m_p_parent = p_new_root;
 257   p_new_root->m_p_parent = m_p_head;
 258   apply_update(m_p_head->m_p_parent, (node_update* )this);
 259   _GLIBCXX_DEBUG_ONLY(m_p_head->m_p_parent->assert_valid(this);)
 260 }