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boost/intrusive/list_hook.hpp

/////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright Olaf Krzikalla 2004-2006.
// (C) Copyright Ion Gaztanaga  2006-2013
//
// 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_LIST_HOOK_HPP
#define BOOST_INTRUSIVE_LIST_HOOK_HPP

#include <boost/intrusive/detail/config_begin.hpp>
#include <boost/intrusive/intrusive_fwd.hpp>
#include <boost/intrusive/detail/utilities.hpp>
#include <boost/intrusive/detail/list_node.hpp>
#include <boost/intrusive/circular_list_algorithms.hpp>
#include <boost/intrusive/options.hpp>
#include <boost/intrusive/detail/generic_hook.hpp>

namespace boost {
namespace intrusive {

/// @cond
template<class VoidPointer>
struct get_list_node_algo
{
   typedef circular_list_algorithms<list_node_traits<VoidPointer> > type;
};
/// @endcond

//! Helper metafunction to define a \c \c list_base_hook that yields to the same
//! type when the same options (either explicitly or implicitly) are used.
#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED) || defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
template<class ...Options>
#else
template<class O1 = void, class O2 = void, class O3 = void>
#endif
struct make_list_base_hook
{
   /// @cond
   typedef typename pack_options
      < hook_defaults,
      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
      O1, O2, O3
      #else
      Options...
      #endif
      >::type packed_options;

   typedef generic_hook
   < get_list_node_algo<typename packed_options::void_pointer>
   , typename packed_options::tag
   , packed_options::link_mode
   , ListBaseHookId
   > implementation_defined;
   /// @endcond
   typedef implementation_defined type;
};

//! Derive a class from this hook in order to store objects of that class
//! in an list.
//!
//! The hook admits the following options: \c tag<>, \c void_pointer<> and
//! \c link_mode<>.
//!
//! \c tag<> defines a tag to identify the node.
//! The same tag value can be used in different classes, but if a class is
//! derived from more than one \c list_base_hook, then each \c list_base_hook needs its
//! unique tag.
//!
//! \c link_mode<> will specify the linking mode of the hook (\c normal_link,
//! \c auto_unlink or \c safe_link).
//!
//! \c void_pointer<> is the pointer type that will be used internally in the hook
//! and the container configured to use this hook.
#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED) || defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
template<class ...Options>
#else
template<class O1, class O2, class O3>
#endif
class list_base_hook
   :  public make_list_base_hook
      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
      <O1, O2, O3>
      #else
      <Options...>
      #endif
      ::type
{
   #if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
   public:
   //! <b>Effects</b>: If link_mode is \c auto_unlink or \c safe_link
   //!   initializes the node to an unlinked state.
   //!
   //! <b>Throws</b>: Nothing.
   list_base_hook();

   //! <b>Effects</b>: If link_mode is \c auto_unlink or \c safe_link
   //!   initializes the node to an unlinked state. The argument is ignored.
   //!
   //! <b>Throws</b>: Nothing.
   //!
   //! <b>Rationale</b>: Providing a copy-constructor
   //!   makes classes using the hook STL-compliant without forcing the
   //!   user to do some additional work. \c swap can be used to emulate
   //!   move-semantics.
   list_base_hook(const list_base_hook& );

   //! <b>Effects</b>: Empty function. The argument is ignored.
   //!
   //! <b>Throws</b>: Nothing.
   //!
   //! <b>Rationale</b>: Providing an assignment operator
   //!   makes classes using the hook STL-compliant without forcing the
   //!   user to do some additional work. \c swap can be used to emulate
   //!   move-semantics.
   list_base_hook& operator=(const list_base_hook& );

   //! <b>Effects</b>: If link_mode is \c normal_link, the destructor does
   //!   nothing (ie. no code is generated). If link_mode is \c safe_link and the
   //!   object is stored in an list an assertion is raised. If link_mode is
   //!   \c auto_unlink and \c is_linked() is true, the node is unlinked.
   //!
   //! <b>Throws</b>: Nothing.
   ~list_base_hook();

   //! <b>Effects</b>: Swapping two nodes swaps the position of the elements
   //!   related to those nodes in one or two containers. That is, if the node
   //!   this is part of the element e1, the node x is part of the element e2
   //!   and both elements are included in the containers s1 and s2, then after
   //!   the swap-operation e1 is in s2 at the position of e2 and e2 is in s1
   //!   at the position of e1. If one element is not in a container, then
   //!   after the swap-operation the other element is not in a container.
   //!   Iterators to e1 and e2 related to those nodes are invalidated.
   //!
   //! <b>Complexity</b>: Constant
   //!
   //! <b>Throws</b>: Nothing.
   void swap_nodes(list_base_hook &other);

   //! <b>Precondition</b>: link_mode must be \c safe_link or \c auto_unlink.
   //!
   //! <b>Returns</b>: true, if the node belongs to a container, false
   //!   otherwise. This function can be used to test whether \c list::iterator_to
   //!   will return a valid iterator.
   //!
   //! <b>Complexity</b>: Constant
   bool is_linked() const;

   //! <b>Effects</b>: Removes the node if it's inserted in a container.
   //!   This function is only allowed if link_mode is \c auto_unlink.
   //!
   //! <b>Throws</b>: Nothing.
   void unlink();
   #endif
};

//! Helper metafunction to define a \c \c list_member_hook that yields to the same
//! type when the same options (either explicitly or implicitly) are used.
#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED) || defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
template<class ...Options>
#else
template<class O1 = void, class O2 = void, class O3 = void>
#endif
struct make_list_member_hook
{
   /// @cond
   typedef typename pack_options
      < hook_defaults,
      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
      O1, O2, O3
      #else
      Options...
      #endif
      >::type packed_options;

   typedef generic_hook
   < get_list_node_algo<typename packed_options::void_pointer>
   , member_tag
   , packed_options::link_mode
   , NoBaseHookId
   > implementation_defined;
   /// @endcond
   typedef implementation_defined type;
};

//! Store this hook in a class to be inserted
//! in an list.
//!
//! The hook admits the following options: \c void_pointer<> and
//! \c link_mode<>.
//!
//! \c link_mode<> will specify the linking mode of the hook (\c normal_link,
//! \c auto_unlink or \c safe_link).
//!
//! \c void_pointer<> is the pointer type that will be used internally in the hook
//! and the container configured to use this hook.
#if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED) || defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
template<class ...Options>
#else
template<class O1, class O2, class O3>
#endif
class list_member_hook
   :  public make_list_member_hook
      #if !defined(BOOST_INTRUSIVE_VARIADIC_TEMPLATES)
      <O1, O2, O3>
      #else
      <Options...>
      #endif
      ::type
{
   #if defined(BOOST_INTRUSIVE_DOXYGEN_INVOKED)
   public:
   //! <b>Effects</b>: If link_mode is \c auto_unlink or \c safe_link
   //!   initializes the node to an unlinked state.
   //!
   //! <b>Throws</b>: Nothing.
   list_member_hook();

   //! <b>Effects</b>: If link_mode is \c auto_unlink or \c safe_link
   //!   initializes the node to an unlinked state. The argument is ignored.
   //!
   //! <b>Throws</b>: Nothing.
   //!
   //! <b>Rationale</b>: Providing a copy-constructor
   //!   makes classes using the hook STL-compliant without forcing the
   //!   user to do some additional work. \c swap can be used to emulate
   //!   move-semantics.
   list_member_hook(const list_member_hook& );

   //! <b>Effects</b>: Empty function. The argument is ignored.
   //!
   //! <b>Throws</b>: Nothing.
   //!
   //! <b>Rationale</b>: Providing an assignment operator
   //!   makes classes using the hook STL-compliant without forcing the
   //!   user to do some additional work. \c swap can be used to emulate
   //!   move-semantics.
   list_member_hook& operator=(const list_member_hook& );

   //! <b>Effects</b>: If link_mode is \c normal_link, the destructor does
   //!   nothing (ie. no code is generated). If link_mode is \c safe_link and the
   //!   object is stored in an list an assertion is raised. If link_mode is
   //!   \c auto_unlink and \c is_linked() is true, the node is unlinked.
   //!
   //! <b>Throws</b>: Nothing.
   ~list_member_hook();

   //! <b>Effects</b>: Swapping two nodes swaps the position of the elements
   //!   related to those nodes in one or two containers. That is, if the node
   //!   this is part of the element e1, the node x is part of the element e2
   //!   and both elements are included in the containers s1 and s2, then after
   //!   the swap-operation e1 is in s2 at the position of e2 and e2 is in s1
   //!   at the position of e1. If one element is not in a container, then
   //!   after the swap-operation the other element is not in a container.
   //!   Iterators to e1 and e2 related to those nodes are invalidated.
   //!
   //! <b>Complexity</b>: Constant
   //!
   //! <b>Throws</b>: Nothing.
   void swap_nodes(list_member_hook &other);

   //! <b>Precondition</b>: link_mode must be \c safe_link or \c auto_unlink.
   //!
   //! <b>Returns</b>: true, if the node belongs to a container, false
   //!   otherwise. This function can be used to test whether \c list::iterator_to
   //!   will return a valid iterator.
   //!
   //! <b>Complexity</b>: Constant
   bool is_linked() const;

   //! <b>Effects</b>: Removes the node if it's inserted in a container.
   //!   This function is only allowed if link_mode is \c auto_unlink.
   //!
   //! <b>Throws</b>: Nothing.
   void unlink();
   #endif
};

} //namespace intrusive
} //namespace boost

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

#endif //BOOST_INTRUSIVE_LIST_HOOK_HPP