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 node_iterators.hpp
44 * Contains an implementation class for ov_tree_.
45 */
46
47#ifndef PB_DS_OV_TREE_NODE_ITERATORS_HPP
48#define PB_DS_OV_TREE_NODE_ITERATORS_HPP
49
50#include <ext/pb_ds/tag_and_trait.hpp>
51#include <ext/pb_ds/detail/type_utils.hpp>
52#include <debug/debug.h>
53
54namespace pb_ds
55{
56  namespace detail
57  {
58#define PB_DS_STATIC_ASSERT(UNIQUE, E)					\
59    typedef								\
60    static_assert_dumclass<sizeof(static_assert<(bool)(E)>)> \
61    UNIQUE##static_assert_type
62
63#define PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC			\
64    ov_tree_node_const_it_<Value_Type, Metadata_Type, Allocator>
65
66    // Const node reference.
67    template<typename Value_Type, typename Metadata_Type, class Allocator>
68    class ov_tree_node_const_it_
69    {
70
71    protected:
72      typedef
73      typename Allocator::template rebind<
74      Value_Type>::other::pointer
75      pointer;
76
77      typedef
78      typename Allocator::template rebind<
79	Value_Type>::other::const_pointer
80      const_pointer;
81
82      typedef
83      typename Allocator::template rebind<
84	Metadata_Type>::other::const_pointer
85      const_metadata_pointer;
86
87      typedef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC this_type;
88
89    protected:
90
91      template<typename Ptr>
92      inline static Ptr
93      mid_pointer(Ptr p_begin, Ptr p_end)
94      {
95	_GLIBCXX_DEBUG_ASSERT(p_end >= p_begin);
96	return (p_begin + (p_end - p_begin) / 2);
97      }
98
99    public:
100
101      typedef trivial_iterator_tag iterator_category;
102
103      typedef trivial_iterator_difference_type difference_type;
104
105      typedef
106      typename Allocator::template rebind<
107	Value_Type>::other::const_pointer
108      value_type;
109
110      typedef
111      typename Allocator::template rebind<
112	typename remove_const<
113	Value_Type>::type>::other::const_pointer
114      reference;
115
116      typedef
117      typename Allocator::template rebind<
118	typename remove_const<
119	Value_Type>::type>::other::const_pointer
120      const_reference;
121
122      typedef Metadata_Type metadata_type;
123
124      typedef
125      typename Allocator::template rebind<
126	metadata_type>::other::const_reference
127      const_metadata_reference;
128
129    public:
130      inline
131      ov_tree_node_const_it_(const_pointer p_nd = NULL,  const_pointer p_begin_nd = NULL,  const_pointer p_end_nd = NULL,  const_metadata_pointer p_metadata = NULL) : 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)
132      { }
133
134      inline const_reference
135      operator*() const
136      { return m_p_value; }
137
138      inline const_metadata_reference
139      get_metadata() const
140      {
141	enum
142	  {
143	    has_metadata = !is_same<Metadata_Type, null_node_metadata>::value
144	  };
145
146	PB_DS_STATIC_ASSERT(should_have_metadata, has_metadata);
147	_GLIBCXX_DEBUG_ASSERT(m_p_metadata != NULL);
148	return *m_p_metadata;
149      }
150
151      inline this_type
152      get_l_child() const
153      {
154	if (m_p_begin_value == m_p_value)
155	  return (this_type(m_p_begin_value, m_p_begin_value, m_p_begin_value));
156
157	const_metadata_pointer p_begin_metadata =
158	  m_p_metadata - (m_p_value - m_p_begin_value);
159
160	return (this_type(mid_pointer(m_p_begin_value, m_p_value),
161			  m_p_begin_value,
162			  m_p_value,
163			  mid_pointer(p_begin_metadata, m_p_metadata)));
164      }
165
166      inline this_type
167      get_r_child() const
168      {
169	if (m_p_value == m_p_end_value)
170	  return (this_type(m_p_end_value,  m_p_end_value,  m_p_end_value));
171
172	const_metadata_pointer p_end_metadata =
173	  m_p_metadata + (m_p_end_value - m_p_value);
174
175	return (this_type(mid_pointer(m_p_value + 1, m_p_end_value),
176			  m_p_value + 1,
177			  m_p_end_value,(m_p_metadata == NULL) ?
178			  NULL : mid_pointer(m_p_metadata + 1, p_end_metadata)));
179      }
180
181      inline bool
182      operator==(const this_type& other) const
183      {
184	const bool is_end = m_p_begin_value == m_p_end_value;
185	const bool is_other_end = other.m_p_begin_value == other.m_p_end_value;
186
187	if (is_end)
188	  return (is_other_end);
189
190	if (is_other_end)
191	  return (is_end);
192
193	return m_p_value == other.m_p_value;
194      }
195
196      inline bool
197      operator!=(const this_type& other) const
198      { return !operator==(other); }
199
200    public:
201      pointer m_p_value;
202      pointer m_p_begin_value;
203      pointer m_p_end_value;
204
205      const_metadata_pointer m_p_metadata;
206    };
207
208#define PB_DS_OV_TREE_NODE_ITERATOR_C_DEC			\
209    ov_tree_node_it_<Value_Type, Metadata_Type, Allocator>
210
211    // Node reference.
212    template<typename Value_Type, typename Metadata_Type, class Allocator>
213    class ov_tree_node_it_ : public PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC
214    {
215
216    private:
217      typedef PB_DS_OV_TREE_NODE_ITERATOR_C_DEC this_type;
218
219      typedef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC base_type;
220
221      typedef typename base_type::pointer pointer;
222
223      typedef typename base_type::const_pointer const_pointer;
224
225      typedef
226      typename base_type::const_metadata_pointer
227      const_metadata_pointer;
228
229    public:
230
231      typedef trivial_iterator_tag iterator_category;
232
233      typedef trivial_iterator_difference_type difference_type;
234
235      typedef
236      typename Allocator::template rebind<
237	Value_Type>::other::pointer
238      value_type;
239
240      typedef
241      typename Allocator::template rebind<
242	typename remove_const<
243	Value_Type>::type>::other::pointer
244      reference;
245
246      typedef
247      typename Allocator::template rebind<
248	typename remove_const<
249	Value_Type>::type>::other::pointer
250      const_reference;
251
252    public:
253      inline
254      ov_tree_node_it_(const_pointer p_nd = NULL,  const_pointer p_begin_nd = NULL,  const_pointer p_end_nd = NULL,  const_metadata_pointer p_metadata = NULL) : base_type(                p_nd,  p_begin_nd,  p_end_nd,  p_metadata)
255      { }
256
257      // Access.
258      inline reference
259      operator*() const
260      { return reference(base_type::m_p_value); }
261
262      // Returns the node reference associated with the left node.
263      inline ov_tree_node_it_
264      get_l_child() const
265      {
266	if (base_type::m_p_begin_value == base_type::m_p_value)
267	  return (this_type(base_type::m_p_begin_value,  base_type::m_p_begin_value,  base_type::m_p_begin_value));
268
269	const_metadata_pointer p_begin_metadata =
270	  base_type::m_p_metadata - (base_type::m_p_value - base_type::m_p_begin_value);
271
272	return (this_type(base_type::mid_pointer(base_type::m_p_begin_value, base_type::m_p_value),
273			  base_type::m_p_begin_value,
274			  base_type::m_p_value,
275			  base_type::mid_pointer(p_begin_metadata, base_type::m_p_metadata)));
276      }
277
278      // Returns the node reference associated with the right node.
279      inline ov_tree_node_it_
280      get_r_child() const
281      {
282	if (base_type::m_p_value == base_type::m_p_end_value)
283	  return (this_type(base_type::m_p_end_value,  base_type::m_p_end_value,  base_type::m_p_end_value));
284
285	const_metadata_pointer p_end_metadata =
286	  base_type::m_p_metadata + (base_type::m_p_end_value - base_type::m_p_value);
287
288	return (this_type(base_type::mid_pointer(base_type::m_p_value + 1, base_type::m_p_end_value),
289			  base_type::m_p_value + 1,
290			  base_type::m_p_end_value,(base_type::m_p_metadata == NULL)?
291			  NULL : base_type::mid_pointer(base_type::m_p_metadata + 1, p_end_metadata)));
292      }
293
294    };
295
296#undef PB_DS_OV_TREE_NODE_ITERATOR_C_DEC
297#undef PB_DS_OV_TREE_CONST_NODE_ITERATOR_C_DEC
298#undef PB_DS_STATIC_ASSERT
299
300} // namespace detail
301} // namespace pb_ds
302
303#endif
304