source: mainline/uspace/lib/cpp/include/__bits/adt/list_node.hpp

/*
 * Copyright (c) 2018 Jaroslav Jindrak
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef LIBCPP_BITS_ADT_LIST_NODE
#define LIBCPP_BITS_ADT_LIST_NODE

namespace std::aux
{
    template<class T>
    struct list_node
    {
        T value;
        list_node* next;
        list_node* prev;

        template<class... Args>
        list_node(Args&&... args)
            : value{forward<Args>(args)...},
              next{}, prev{}
        {
            next = this;
            prev = this;
        }

        list_node(const T& val)
            : value{val}, next{}, prev{}
        {
            next = this;
            prev = this;
        }

        list_node(T&& val)
            : value{forward<T>(val)}, next{}, prev{}
        {
            next = this;
            prev = this;
        }

        void append(list_node* node)
        {
            if (!node)
                return;

            node->next = next;
            node->prev = this;
            next->prev = node;
            next = node;
        }

        void prepend(list_node* node)
        {
            if (!node)
                return;

            node->next = this;
            node->prev = prev;
            prev->next = node;
            prev = node;
        }

        void unlink()
        {
            prev->next = next;
            next->prev = prev;
            next = this;
            prev = this;
        }
    };
}

#endif