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
47PB_DS_CLASS_T_DEC
48void
49PB_DS_CLASS_C_DEC::
50split(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
86PB_DS_CLASS_T_DEC
87typename PB_DS_CLASS_C_DEC::leaf_pointer
88PB_DS_CLASS_C_DEC::
89split_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(map_debug_base::split(r_key,(synth_e_access_traits& )(*this), other);)
132
133  return (p_ret_l);
134}
135
136PB_DS_CLASS_T_DEC
137typename PB_DS_CLASS_C_DEC::node_pointer
138PB_DS_CLASS_C_DEC::
139rec_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
205PB_DS_CLASS_T_DEC
206void
207PB_DS_CLASS_C_DEC::
208split_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}
261