libstdc++-v3/include/ext/pb_ds/detail/ov_tree_map_/node_iterators.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2019 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 ov_tree_map_/node_iterators.hpp
  38  * Contains an implementation class for ov_tree_.
  39  */
  40
  41 #ifndef PB_DS_OV_TREE_NODE_ITERATORS_HPP
  42 #define PB_DS_OV_TREE_NODE_ITERATORS_HPP
  43
  44 #include <ext/pb_ds/tag_and_trait.hpp>
  45 #include <ext/pb_ds/detail/type_utils.hpp>
  46 #include <debug/debug.h>
  47
  48 namespace __gnu_pbds
  49 {
  50   namespace detail
  51   {
  52 #define PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC \
  53     ov_tree_node_const_it_<Value_Type, Metadata_Type, _Alloc>
  54
  55     /// Const node reference.
  56     template<typename Value_Type, typename Metadata_Type, typename _Alloc>
  57     class ov_tree_node_const_it_
  58     {
  59
  60     protected:
  61       typedef
  62       typename _Alloc::template rebind<
  63       Value_Type>::other::pointer
  64       pointer;
  65
  66       typedef
  67       typename _Alloc::template rebind<
  68         Value_Type>::other::const_pointer
  69       const_pointer;
  70
  71       typedef
  72       typename _Alloc::template rebind<
  73         Metadata_Type>::other::const_pointer
  74       const_metadata_pointer;
  75
  76       typedef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC this_type;
  77
  78     protected:
  79
  80       template<typename Ptr>
  81       inline static Ptr
  82       mid_pointer(Ptr p_begin, Ptr p_end)
  83       {
  84         _GLIBCXX_DEBUG_ASSERT(p_end >= p_begin);
  85         return (p_begin + (p_end - p_begin) / 2);
  86       }
  87
  88     public:
  89
  90       typedef trivial_iterator_tag iterator_category;
  91
  92       typedef trivial_iterator_difference_type difference_type;
  93
  94       typedef
  95       typename _Alloc::template rebind<
  96         Value_Type>::other::const_pointer
  97       value_type;
  98
  99       typedef
 100       typename _Alloc::template rebind<
 101         typename remove_const<
 102         Value_Type>::type>::other::const_pointer
 103       reference;
 104
 105       typedef
 106       typename _Alloc::template rebind<
 107         typename remove_const<
 108         Value_Type>::type>::other::const_pointer
 109       const_reference;
 110
 111       typedef Metadata_Type metadata_type;
 112
 113       typedef
 114       typename _Alloc::template rebind<
 115         metadata_type>::other::const_reference
 116       metadata_const_reference;
 117
 118     public:
 119       inline
 120       ov_tree_node_const_it_(const_pointer p_nd = 0,  const_pointer p_begin_nd = 0,  const_pointer p_end_nd = 0,  const_metadata_pointer p_metadata = 0) : m_p_value(const_cast<pointer>(p_nd)), m_p_begin_value(const_cast<pointer>(p_begin_nd)), m_p_end_value(const_cast<pointer>(p_end_nd)), m_p_metadata(p_metadata)
 121       { }
 122
 123       inline const_reference
 124       operator*() const
 125       { return m_p_value; }
 126
 127       inline metadata_const_reference
 128       get_metadata() const
 129       {
 130         enum
 131           {
 132             has_metadata = !is_same<Metadata_Type, null_type>::value
 133           };
 134
 135         PB_DS_STATIC_ASSERT(should_have_metadata, has_metadata);
 136         _GLIBCXX_DEBUG_ASSERT(m_p_metadata != 0);
 137         return *m_p_metadata;
 138       }
 139
 140       /// Returns the node iterator associated with the left node.
 141       inline this_type
 142       get_l_child() const
 143       {
 144         if (m_p_begin_value == m_p_value)
 145           return (this_type(m_p_begin_value, m_p_begin_value, m_p_begin_value));
 146
 147         const_metadata_pointer p_begin_metadata =
 148           m_p_metadata - (m_p_value - m_p_begin_value);
 149
 150         return (this_type(mid_pointer(m_p_begin_value, m_p_value),
 151                           m_p_begin_value,
 152                           m_p_value,
 153                           mid_pointer(p_begin_metadata, m_p_metadata)));
 154       }
 155
 156       /// Returns the node iterator associated with the right node.
 157       inline this_type
 158       get_r_child() const
 159       {
 160         if (m_p_value == m_p_end_value)
 161           return (this_type(m_p_end_value, m_p_end_value, m_p_end_value));
 162
 163         const_metadata_pointer p_end_metadata =
 164           m_p_metadata + (m_p_end_value - m_p_value);
 165
 166         return (this_type(mid_pointer(m_p_value + 1, m_p_end_value),
 167                           m_p_value + 1,
 168                           m_p_end_value,(m_p_metadata == 0) ?
 169                           0 : mid_pointer(m_p_metadata + 1, p_end_metadata)));
 170       }
 171
 172       inline bool
 173       operator==(const this_type& other) const
 174       {
 175         const bool is_end = m_p_begin_value == m_p_end_value;
 176         const bool is_other_end = other.m_p_begin_value == other.m_p_end_value;
 177
 178         if (is_end)
 179           return (is_other_end);
 180
 181         if (is_other_end)
 182           return (is_end);
 183
 184         return m_p_value == other.m_p_value;
 185       }
 186
 187       inline bool
 188       operator!=(const this_type& other) const
 189       { return !operator==(other); }
 190
 191     public:
 192       pointer m_p_value;
 193       pointer m_p_begin_value;
 194       pointer m_p_end_value;
 195
 196       const_metadata_pointer m_p_metadata;
 197     };
 198
 199 #define PB_DS_OV_TREE_NODE_ITERATOR_C_DEC \
 200     ov_tree_node_it_<Value_Type, Metadata_Type, _Alloc>
 201
 202     /// Node reference.
 203     template<typename Value_Type, typename Metadata_Type, typename _Alloc>
 204     class ov_tree_node_it_ : public PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC
 205     {
 206     private:
 207       typedef PB_DS_OV_TREE_NODE_ITERATOR_C_DEC this_type;
 208
 209       typedef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC base_type;
 210
 211       typedef typename base_type::pointer pointer;
 212
 213       typedef typename base_type::const_pointer const_pointer;
 214
 215       typedef
 216       typename base_type::const_metadata_pointer
 217       const_metadata_pointer;
 218
 219     public:
 220       typedef trivial_iterator_tag iterator_category;
 221
 222       typedef trivial_iterator_difference_type difference_type;
 223
 224       typedef
 225       typename _Alloc::template rebind<
 226         Value_Type>::other::pointer
 227       value_type;
 228
 229       typedef
 230       typename _Alloc::template rebind<
 231         typename remove_const<
 232         Value_Type>::type>::other::pointer
 233       reference;
 234
 235       typedef
 236       typename _Alloc::template rebind<
 237         typename remove_const<
 238         Value_Type>::type>::other::pointer
 239       const_reference;
 240
 241       inline
 242       ov_tree_node_it_(const_pointer p_nd = 0,  const_pointer p_begin_nd = 0,  const_pointer p_end_nd = 0,  const_metadata_pointer p_metadata = 0) : base_type(p_nd,  p_begin_nd,  p_end_nd,  p_metadata)
 243       { }
 244
 245       /// Access.
 246       inline reference
 247       operator*() const
 248       { return reference(base_type::m_p_value); }
 249
 250       /// Returns the node reference associated with the left node.
 251       inline ov_tree_node_it_
 252       get_l_child() const
 253       {
 254         if (base_type::m_p_begin_value == base_type::m_p_value)
 255           return (this_type(base_type::m_p_begin_value,  base_type::m_p_begin_value,  base_type::m_p_begin_value));
 256
 257         const_metadata_pointer p_begin_metadata =
 258           base_type::m_p_metadata - (base_type::m_p_value - base_type::m_p_begin_value);
 259
 260         return (this_type(base_type::mid_pointer(base_type::m_p_begin_value, base_type::m_p_value),
 261                           base_type::m_p_begin_value,
 262                           base_type::m_p_value,
 263                           base_type::mid_pointer(p_begin_metadata, base_type::m_p_metadata)));
 264       }
 265
 266       /// Returns the node reference associated with the right node.
 267       inline ov_tree_node_it_
 268       get_r_child() const
 269       {
 270         if (base_type::m_p_value == base_type::m_p_end_value)
 271           return this_type(base_type::m_p_end_value, base_type::m_p_end_value,
 272                            base_type::m_p_end_value);
 273
 274         const_metadata_pointer p_end_metadata =
 275           base_type::m_p_metadata + (base_type::m_p_end_value - base_type::m_p_value);
 276
 277         return (this_type(base_type::mid_pointer(base_type::m_p_value + 1, base_type::m_p_end_value),
 278                           base_type::m_p_value + 1,
 279                           base_type::m_p_end_value,(base_type::m_p_metadata == 0)?
 280                           0 : base_type::mid_pointer(base_type::m_p_metadata + 1, p_end_metadata)));
 281       }
 282
 283     };
 284
 285 #undef PB_DS_OV_TREE_NODE_ITERATOR_C_DEC
 286 #undef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC
 287
 288 } // namespace detail
 289 } // namespace __gnu_pbds
 290
 291 #endif