This file is indexed.

/usr/include/CGAL/Skiplist.h is in libcgal-dev 4.7-4.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
// Copyright (c) 2012 GeometryFactory (France). All rights reserved.
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 3 of the License,
// or (at your option) any later version.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL:
// $Id:
//
// Author(s)     : Philipp Moeller

#ifndef CGAL_SKIPLIST_H
#define CGAL_SKIPLIST_H

#include <boost/intrusive/list.hpp>
#include <boost/range/iterator_range.hpp>
#include <boost/iterator/iterator_adaptor.hpp>

namespace CGAL {

/// The skiplist maintains two iterator ranges on the set of elements:
/// the all view and the skip view. The all view at all times contains
/// all elements in the Skiplist. The skip view can be modified and
/// items can be removed from it.
///
/// insert will add elements to the all_view.
///
/// @tparam T the value_type to store in the Skiplist
template<typename T>
class Skiplist
{
public:
  typedef T        value_type;
  typedef T&       reference;
  typedef const T& const_reference;
  typedef T*       pointer;
  typedef const T* const_pointer;
  
private:
  struct Node {
    explicit Node(const T& t) : t_(t) {}
    const T& get() const { return t_; }
    T& get() { return t_; }
  private:
    value_type t_;
  public:
    boost::intrusive::list_member_hook<> skip_hook;
    boost::intrusive::list_member_hook<> all_hook;
  };

  struct Node_disposer {
    void operator()(Node* p) const { delete p; }
  };

  typedef boost::intrusive::member_hook<
    Node,
    boost::intrusive::list_member_hook<>,
    &Node::skip_hook>
  SkipOption;
  typedef boost::intrusive::member_hook<
    Node,
    boost::intrusive::list_member_hook<>,
    &Node::all_hook>
  AllOption;

  typedef boost::intrusive::list<Node, SkipOption> skip_list;
  typedef boost::intrusive::list<Node, AllOption> all_list;
public:
  // assume both lists have the same size_type/ptr_diff
  typedef typename all_list::size_type size_type;
  typedef typename all_list::difference_type difference_type;

  struct all_iterator : 
    public boost::iterator_adaptor<
      all_iterator
    , typename all_list::iterator
    , T
    >
  {
  public:
    all_iterator() {}
    all_iterator(typename all_list::iterator it) 
      : all_iterator::iterator_adaptor_(it) {}
  private:
    friend class boost::iterator_core_access;
    T& dereference() const { return this->base()->get(); }
  };

  struct skip_iterator : 
    public boost::iterator_adaptor<
      skip_iterator
    , typename skip_list::iterator
    , T
    >
  {
  public:
    skip_iterator() {}
    skip_iterator(typename skip_list::iterator it) 
      : skip_iterator::iterator_adaptor_(it) {}
    operator all_iterator() const { return all_list::s_iterator_to(*this->base()); }
  private:
    friend class boost::iterator_core_access;
    T& dereference() const { return this->base()->get(); }
  };
  
  typedef boost::iterator_range<all_iterator>  all_range;
  typedef boost::iterator_range<skip_iterator> skip_range;

  Skiplist() {}
  ~Skiplist() 
  {
    clear();
  }

  /// Construct a Skiplist from the range [begin,end)
  /// @postcond Both views are equal to the range [begin,end)
  template<typename InputIterator>
  Skiplist(InputIterator begin, InputIterator end)
  {
    while(begin != end) {
      push_back(*begin++);
    }
  }

  /// The semantics of front and back try to be consistent with
  /// push_back and push_front. Questionable.
  
  /// Returns front of the skiplist
  const_reference
  front() const { return skip_.front().get(); }

  /// Returns front of the skiplist
  reference
  front() { return skip_.front().get(); }

  /// Returns back of the skiplist
  const_reference
  back() const { return skip_.back().get(); }

  /// Returns back of the skiplist
  reference
  back() { return skip_.back().get(); }
  
  all_iterator all_begin() 
  { 
    return all_.begin();
  }
  all_iterator all_end() 
  { 
    return all_.end();
  }

  skip_iterator skip_begin()
  {
    return skip_.begin();
  }
  skip_iterator skip_end()
  {
    return skip_.end();
  }

  all_range
  all_elements()
  {
    return boost::make_iterator_range(all_begin(), all_end());
  }

  skip_range
  skip_elements()
  {
    return boost::make_iterator_range(skip_begin(), skip_end());
  }

  /// The elements pointed to by it are no longer in the range
  /// [skip_begin(), skip_end()).
  void skip(skip_iterator it)
  {
    skip_.erase(it.base());
  }

  /// The elements pointed to by it are no longer in the range
  /// [skip_begin(), skip_end()).
  ///
  /// @precond it and to_skip(it) are valid iterators
  ///
  void skip(all_iterator it)
  {
    skip_.erase(skip_.iterator_to((*it.base())));
  }

  /// The elements pointed to by [begin, end) are no longer in the
  /// range [skip_begin(), skip_end()). If an element in [begin, end)
  /// already is removed from the skip view, it will stay removed.
  ///
  /// @precond [begin,end) is a slice of the range [all_begin(), all_end())
  ///
  void skip(all_iterator begin, all_iterator end)
  {
    if(end == all_end()) {
      skip_.erase(skip_.iterator_to(*begin.base()), skip_.end());
    } else {
      skip_.erase(skip_.iterator_to(*begin.base()), skip_.iterator_to(*end.base()));
    }
  }

  void unskip(skip_iterator pos, all_iterator it)
  {
    skip_.insert(pos.base(), *(it.base()));
  }

  /// Check if an all_iterator has been skipped.
  ///
  /// @param it a valid all_iterator
  ///
  /// @return true if the element pointed to by it is not in the range [skip_begin(), skip_end())
  bool is_skipped(all_iterator it) const
  {
    return !(it.base()->skip_hook.is_linked());
  }

  /// Adds an element to the end of both views in Skiplist.
  void push_back(const value_type& t)
  {
    all_.push_back(*new Node(t));
    skip_.push_back(all_.back());
  }

  /// Adds an element to the front of both views in Skiplist.
  void push_front(const value_type& t)
  {
    all_.push_front(*new Node(t));
    skip_.push_front(all_.front());
  }

  void pop_back()
  {
    all_.pop_back();
    skip_.pop_back();
  }

  /// Insert \c t before \c pos in the all_view. \t will not be inserted into the skip view.
  /// @returns an skip_iterator to the inserted element.
  all_iterator insert(all_iterator pos, const value_type& t)
  {
    return all_.insert(pos.base(), *new Node(t));
  }

  /// Insert \c t before \c pos in the all_view. \t will be inserted into the skip view.
  /// @returns an iterator to the inserted element.
  skip_iterator insert(skip_iterator pos, const value_type& t)
  {
    all_iterator it = insert(static_cast<all_iterator>(pos), t);
    return skip_.insert(pos.base(), *it.base());
  }

  /// Insert the range [begin,end) into the all view. If the container
  /// is empty() the range will also be visible in the skip view.
  template<typename InputIterator>
  void insert(all_iterator pos, InputIterator begin, InputIterator end)
  {
    if(all_.empty()) {
      while(begin != end) {
        push_back(*begin++);
      }
    } else {
      while(begin != end) {
        pos = insert(pos, *begin++);
      }
    }
  }

  /// Drop the contents of iterator \c it from both views.
  all_iterator erase(all_iterator it)
  {
    if(!is_skipped(it)) {
      skip_.erase(skip_.iterator_to(*it.base()));
    }

    return all_.erase_and_dispose(it.base(), Node_disposer());
  }

  void splice(skip_iterator pos, Skiplist& other, 
              skip_iterator first, skip_iterator last)
  {
    all_iterator alllast = last == other.skip_end() ? 
      other.all_.end() : other.all_.iterator_to(*last.base());
    all_iterator allpos = pos == skip_end() ?
      all_end() : all_.iterator_to(*pos.base());
    
    all_.splice(allpos.base(), other.all_, 
                other.all_.iterator_to(*first.base()), alllast.base());
    skip_.splice(pos.base(), other.skip_, first.base(), last.base());
  }

  size_type
  all_size() const { return all_.size(); }

  size_type
  skip_size() const { return skip_.size(); }

  bool empty() const { return all_.empty(); }

  void swap(Skiplist& other) 
  {
    using std::swap;
    this->all_.swap(other.all_);
    this->skip_.swap(other.skip_);
  }

  /// Reset the container.
  /// @postcond *this.empty() == true
  void clear()
  {
    skip_.clear();
    all_.clear_and_dispose(Node_disposer());
  }

private:
  all_list all_;
  skip_list skip_;
};

template<typename T>
void swap(Skiplist<T>& a, Skiplist<T>& b) 
{
  a.swap(b);
}

} // CGAL


#endif /* CGAL_SKIPLIST_H */