libstdc++-v3/src/c++98/list-aux-2.cc

   1 // Compatibility symbols for previous versions, list bits -*- C++ -*-
   2
   3 // Copyright (C) 2011-2021 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
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU 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 #include <bits/move.h>
  26
  27 #ifdef _GLIBCXX_SHARED
  28
  29 #ifndef _GLIBCXX_BEGIN_NAMESPACE_COMPAT
  30 # define _GLIBCXX_BEGIN_NAMESPACE_COMPAT
  31 #endif
  32
  33 #ifndef _GLIBCXX_END_NAMESPACE_COMPAT
  34 # define _GLIBCXX_END_NAMESPACE_COMPAT
  35 #endif
  36
  37 namespace std _GLIBCXX_VISIBILITY(default)
  38 {
  39 _GLIBCXX_BEGIN_NAMESPACE_COMPAT
  40
  41   struct _List_node_base
  42   {
  43     _List_node_base* _M_next;
  44     _List_node_base* _M_prev;
  45
  46     void
  47     _M_transfer(_List_node_base * const __first,
  48                 _List_node_base * const __last) _GLIBCXX_USE_NOEXCEPT;
  49
  50     void
  51     _M_reverse() _GLIBCXX_USE_NOEXCEPT;
  52
  53     void
  54     _M_hook(_List_node_base * const __position) _GLIBCXX_USE_NOEXCEPT;
  55
  56     void
  57     _M_unhook() _GLIBCXX_USE_NOEXCEPT;
  58   };
  59
  60   void
  61   _List_node_base::
  62   _M_transfer(_List_node_base * const __first,
  63               _List_node_base * const __last) _GLIBCXX_USE_NOEXCEPT
  64   {
  65     if (this != __last)
  66     {
  67       // Remove [first, last) from its old position.
  68       __last->_M_prev->_M_next  = this;
  69       __first->_M_prev->_M_next = __last;
  70       this->_M_prev->_M_next    = __first;
  71
  72       // Splice [first, last) into its new position.
  73       _List_node_base* const __tmp = this->_M_prev;
  74       this->_M_prev                = __last->_M_prev;
  75       __last->_M_prev              = __first->_M_prev;
  76       __first->_M_prev             = __tmp;
  77     }
  78   }
  79
  80   void
  81   _List_node_base::_M_reverse() _GLIBCXX_USE_NOEXCEPT
  82   {
  83     _List_node_base* __tmp = this;
  84     do
  85     {
  86       std::swap(__tmp->_M_next, __tmp->_M_prev);
  87
  88       // Old next node is now prev.
  89       __tmp = __tmp->_M_prev;
  90     }
  91     while (__tmp != this);
  92   }
  93
  94   void
  95   _List_node_base::
  96   _M_hook(_List_node_base* const __position) _GLIBCXX_USE_NOEXCEPT
  97   {
  98     this->_M_next = __position;
  99     this->_M_prev = __position->_M_prev;
 100     __position->_M_prev->_M_next = this;
 101     __position->_M_prev = this;
 102   }
 103
 104   void
 105   _List_node_base::_M_unhook() _GLIBCXX_USE_NOEXCEPT
 106   {
 107     _List_node_base* const __next_node = this->_M_next;
 108     _List_node_base* const __prev_node = this->_M_prev;
 109     __prev_node->_M_next = __next_node;
 110     __next_node->_M_prev = __prev_node;
 111   }
 112
 113 _GLIBCXX_END_NAMESPACE_COMPAT
 114
 115 } // namespace std
 116
 117 #endif