/*

Copyright (c) 2016-2017, Alden Torres

Copyright (c) 2016, Steven Siloti

Copyright (c) 2017, 2019, Arvid Norberg

Copyright (c) 2018, Eugene Shalygin

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.

    * Neither the name of the author nor the names of its

      contributors may be used to endorse or promote products derived

      from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER OR CONTRIBUTORS 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 TORRENT_NETLINK_HPP

#define TORRENT_NETLINK_HPP

#include "libtorrent/config.hpp"

#if TORRENT_USE_NETLINK

#include <cstring>

#include <cstdint>

#include "libtorrent/aux_/disable_warnings_push.hpp"

#include <linux/netlink.h>

#include <linux/rtnetlink.h>

#include <boost/asio/basic_raw_socket.hpp>

#include "libtorrent/aux_/disable_warnings_pop.hpp"

namespace libtorrent {

  template <typename Protocol>

  class basic_nl_endpoint

  {

  public:

    using protocol_type = Protocol;

    using data_type = boost::asio::detail::socket_addr_type;

    basic_nl_endpoint() noexcept : basic_nl_endpoint(protocol_type(), 0, 0) {}

    basic_nl_endpoint(protocol_type netlink_family, std::uint32_t group, std::uint32_t pid = 0)

      : m_proto(netlink_family)

    {

      std::memset(&m_sockaddr, 0, sizeof(sockaddr_nl));

      m_sockaddr.nl_family = AF_NETLINK;

      m_sockaddr.nl_groups = group;

      m_sockaddr.nl_pid = pid;

    }

    basic_nl_endpoint(basic_nl_endpoint const& other) = default;

    basic_nl_endpoint(basic_nl_endpoint&& other) noexcept = default;

    basic_nl_endpoint& operator=(basic_nl_endpoint const& other)

    {

      m_sockaddr = other.m_sockaddr;

      return *this;

    }

    basic_nl_endpoint& operator=(basic_nl_endpoint&& other) noexcept

    {

      m_sockaddr = other.m_sockaddr;

      return *this;

    }

    protocol_type protocol() const

    {

      return m_proto;

    }

    data_type* data()

    {

      return reinterpret_cast<data_type*>(&m_sockaddr);

    }

    const data_type* data() const

    {

      return reinterpret_cast<data_type const*>(&m_sockaddr);

    }

    std::size_t size() const

    {

      return sizeof(m_sockaddr);

    }

    std::size_t capacity() const

    {

      return sizeof(m_sockaddr);

    }

    // commented the comparison operators for now, until the

    // same operators are implemented for sockaddr_nl

    /*

    friend bool operator==(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return l.m_sockaddr == r.m_sockaddr;

    }

    friend bool operator!=(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return !(l.m_sockaddr == r.m_sockaddr);

    }

    friend bool operator<(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return l.m_sockaddr < r.m_sockaddr;

    }

    friend bool operator>(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return r.m_sockaddr < l.m_sockaddr;

    }

    friend bool operator<=(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return !(r < l);

    }

    friend bool operator>=(const basic_nl_endpoint<Protocol>& l

      , const basic_nl_endpoint<Protocol>& r)

    {

      return !(l < r);

    }

    */

    private:

      protocol_type m_proto;

      sockaddr_nl m_sockaddr;

  };

  class netlink

  {

  public:

    using endpoint = basic_nl_endpoint<netlink>;

    using socket = boost::asio::basic_raw_socket<netlink>;

    netlink() : netlink(NETLINK_ROUTE) {}

    explicit netlink(int nl_family)

      : m_nl_family(nl_family)

    {

    }

    int type() const

    {

      return SOCK_RAW;

    }

    int protocol() const

    {

      return m_nl_family;

    }

    int family() const

    {

      return AF_NETLINK;

    }

    friend bool operator==(const netlink& l, const netlink& r)

    {

      return l.m_nl_family == r.m_nl_family;

    }

    friend bool operator!=(const netlink& l, const netlink& r)

    {

      return l.m_nl_family != r.m_nl_family;

    }

  private:

    int m_nl_family;

  };

}

#endif // TORRENT_USE_NETLINK

#endif