libstdc++-v3/src/list.cc

   1 // std::list utilities implementation -*- C++ -*-
   2
   3 // Copyright (C) 2003, 2005, 2009, 2010, 2011 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 /*
  26  *
  27  * Copyright (c) 1994
  28  * Hewlett-Packard Company
  29  *
  30  * Permission to use, copy, modify, distribute and sell this software
  31  * and its documentation for any purpose is hereby granted without fee,
  32  * provided that the above copyright notice appear in all copies and
  33  * that both that copyright notice and this permission notice appear
  34  * in supporting documentation.  Hewlett-Packard Company makes no
  35  * representations about the suitability of this software for any
  36  * purpose.  It is provided "as is" without express or implied warranty.
  37  *
  38  *
  39  * Copyright (c) 1996,1997
  40  * Silicon Graphics Computer Systems, Inc.
  41  *
  42  * Permission to use, copy, modify, distribute and sell this software
  43  * and its documentation for any purpose is hereby granted without fee,
  44  * provided that the above copyright notice appear in all copies and
  45  * that both that copyright notice and this permission notice appear
  46  * in supporting documentation.  Silicon Graphics makes no
  47  * representations about the suitability of this software for any
  48  * purpose.  It is provided "as is" without express or implied warranty.
  49  */
  50
  51 #include <list>
  52
  53 namespace std _GLIBCXX_VISIBILITY(default)
  54 {
  55   namespace __detail
  56   {
  57   _GLIBCXX_BEGIN_NAMESPACE_VERSION
  58
  59     void
  60     _List_node_base::swap(_List_node_base& __x, _List_node_base& __y) throw()
  61     {
  62       if ( __x._M_next != &__x )
  63         {
  64           if ( __y._M_next != &__y )
  65             {
  66               // Both __x and __y are not empty.
  67               std::swap(__x._M_next,__y._M_next);
  68               std::swap(__x._M_prev,__y._M_prev);
  69               __x._M_next->_M_prev = __x._M_prev->_M_next = &__x;
  70               __y._M_next->_M_prev = __y._M_prev->_M_next = &__y;
  71             }
  72           else
  73             {
  74               // __x is not empty, __y is empty.
  75               __y._M_next = __x._M_next;
  76               __y._M_prev = __x._M_prev;
  77               __y._M_next->_M_prev = __y._M_prev->_M_next = &__y;
  78               __x._M_next = __x._M_prev = &__x;
  79             }
  80         }
  81       else if ( __y._M_next != &__y )
  82         {
  83           // __x is empty, __y is not empty.
  84           __x._M_next = __y._M_next;
  85           __x._M_prev = __y._M_prev;
  86           __x._M_next->_M_prev = __x._M_prev->_M_next = &__x;
  87           __y._M_next = __y._M_prev = &__y;
  88         }
  89     }
  90
  91     void
  92     _List_node_base::_M_transfer(_List_node_base * const __first,
  93                                  _List_node_base * const __last) throw()
  94     {
  95       if (this != __last)
  96         {
  97           // Remove [first, last) from its old position.
  98           __last->_M_prev->_M_next  = this;
  99           __first->_M_prev->_M_next = __last;
 100           this->_M_prev->_M_next    = __first;
 101
 102           // Splice [first, last) into its new position.
 103           _List_node_base* const __tmp = this->_M_prev;
 104           this->_M_prev                = __last->_M_prev;
 105           __last->_M_prev              = __first->_M_prev;
 106           __first->_M_prev             = __tmp;
 107         }
 108     }
 109
 110     void
 111     _List_node_base::_M_reverse() throw()
 112     {
 113       _List_node_base* __tmp = this;
 114       do
 115         {
 116           std::swap(__tmp->_M_next, __tmp->_M_prev);
 117
 118           // Old next node is now prev.
 119           __tmp = __tmp->_M_prev;
 120         }
 121       while (__tmp != this);
 122     }
 123
 124     void
 125     _List_node_base::_M_hook(_List_node_base* const __position) throw()
 126     {
 127       this->_M_next = __position;
 128       this->_M_prev = __position->_M_prev;
 129       __position->_M_prev->_M_next = this;
 130       __position->_M_prev = this;
 131     }
 132
 133     void
 134     _List_node_base::_M_unhook() throw()
 135     {
 136       _List_node_base* const __next_node = this->_M_next;
 137       _List_node_base* const __prev_node = this->_M_prev;
 138       __prev_node->_M_next = __next_node;
 139       __next_node->_M_prev = __prev_node;
 140     }
 141
 142   _GLIBCXX_END_NAMESPACE_VERSION
 143   } // namespace __detail
 144 } // namespace std