/////////////////////////////////////////////////////////////////////////////

//

// (C) Copyright Ion Gaztanaga  2007-2008

//

// Distributed under the Boost Software License, Version 1.0.

//    (See accompanying file LICENSE_1_0.txt or copy at

//          http://www.boost.org/LICENSE_1_0.txt)

//

// See http://www.boost.org/libs/intrusive for documentation.

//

/////////////////////////////////////////////////////////////////////////////



#ifndef BOOST_INTRUSIVE_COMMON_SLIST_ALGORITHMS_HPP

#define BOOST_INTRUSIVE_COMMON_SLIST_ALGORITHMS_HPP



#include <boost/intrusive/detail/config_begin.hpp>

#include <boost/intrusive/intrusive_fwd.hpp>

#include <boost/intrusive/detail/assert.hpp>

#include <cstddef>



namespace boost {

namespace intrusive {

namespace detail {



template<class NodeTraits>

class common_slist_algorithms

{

   public:

   typedef typename NodeTraits::node_ptr        node_ptr;

   typedef typename NodeTraits::const_node_ptr  const_node_ptr;

   typedef NodeTraits                           node_traits;



   static node_ptr get_previous_node(node_ptr prev_init_node, node_ptr this_node)

   {

      node_ptr p = prev_init_node;

      for( node_ptr p_next

         ; this_node != (p_next = NodeTraits::get_next(p))

         ; p = p_next){

         //Logic error: possible use of linear lists with

         //operations only permitted with lists

         BOOST_INTRUSIVE_INVARIANT_ASSERT(p);

      }

      return p;

   }



   static void init_header(node_ptr this_node)  

   {  NodeTraits::set_next(this_node, this_node);  }  



   static void init(node_ptr this_node)  

   {  NodeTraits::set_next(this_node, 0);  }  



   static bool unique(const_node_ptr this_node)

   {

      node_ptr next = NodeTraits::get_next(this_node);

      return !next || next == this_node;

   }  



   static bool inited(const_node_ptr this_node)  

   {  return !NodeTraits::get_next(this_node); }



   static void unlink_after(node_ptr prev_node)

   {

      node_ptr this_node(NodeTraits::get_next(prev_node));

      NodeTraits::set_next(prev_node, NodeTraits::get_next(this_node));

   }



   static void unlink_after(node_ptr prev_node, node_ptr last_node)

   {  NodeTraits::set_next(prev_node, last_node);  }



   static void link_after(node_ptr prev_node, node_ptr this_node)

   {

      NodeTraits::set_next(this_node, NodeTraits::get_next(prev_node));

      NodeTraits::set_next(prev_node, this_node);

   }



   static void transfer_after(node_ptr p, node_ptr b, node_ptr e)

   {

      if (p != b && p != e) {

         node_ptr next_b = NodeTraits::get_next(b);

         node_ptr next_e = NodeTraits::get_next(e);

         node_ptr next_p = NodeTraits::get_next(p);

         NodeTraits::set_next(b, next_e);

         NodeTraits::set_next(e, next_p);

         NodeTraits::set_next(p, next_b);

      }

   }

};



} //namespace detail

} //namespace intrusive 

} //namespace boost 



#include <boost/intrusive/detail/config_end.hpp>



#endif //BOOST_INTRUSIVE_COMMON_SLIST_ALGORITHMS_HPP

