libstdc++
cond_key_dtor_entry_dealtor.hpp
Go to the documentation of this file.
1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2018 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 cc_hash_table_map_/cond_key_dtor_entry_dealtor.hpp
38  * Contains a conditional key destructor, used for exception handling.
39  */
40 
41 namespace __gnu_pbds
42 {
43  namespace detail
44  {
45  /// Conditional dey destructor, cc_hash.
46  template<typename HT_Map>
47  class cond_dealtor
48  {
49  public:
50  typedef typename HT_Map::entry entry;
51  typedef typename HT_Map::entry_allocator entry_allocator;
52  typedef typename HT_Map::key_type key_type;
53 
54  cond_dealtor(entry_allocator* p_a, entry* p_e)
55  : m_p_a(p_a), m_p_e(p_e), m_key_destruct(false),
56  m_no_action_destructor(false)
57  { }
58 
59  inline
60  ~cond_dealtor();
61 
62  void
63  set_key_destruct()
64  { m_key_destruct = true; }
65 
66  void
67  set_no_action_destructor()
68  { m_no_action_destructor = true; }
69 
70  protected:
71  entry_allocator* const m_p_a;
72  entry* const m_p_e;
73 
74  bool m_key_destruct;
75  bool m_no_action_destructor;
76  };
77 
78  template<typename HT_Map>
79  inline
80  cond_dealtor<HT_Map>::
81  ~cond_dealtor()
82  {
83  if (m_no_action_destructor)
84  return;
85  if (m_key_destruct)
86  m_p_e->m_value.first.~key_type();
87  m_p_a->deallocate(m_p_e, 1);
88  }
89  } // namespace detail
90 } // namespace __gnu_pbds
GNU extensions for policy-based data structures for public use.