使用 boost 的源特定多播答案

【问题标题】：source-specific multicast using boost使用 boost 的源特定多播
【发布时间】：2011-12-26 15:27:34
【问题描述】：

如何使用 boost 加入特定于源的多播 (ssm) 组？

我已经使用

成功加入了任意源多播组

set_option( ip::multicast::join_group( mcAddr.to_v4(), ifAddr.to_v4( )));

但我不知道如何设置 ssm (IP_ADD_SOURCE_MEMBERSHIP)。

我该怎么做？谢谢。

【问题讨论】：

标签： c++ boost udp boost-asio multicast

【解决方案1】：

是的。我用这个

//---------------------------------------------------------------------------------------------------------
// class add_source_membership_v4
// is for Windows Sockets 2 IPv4
// to set IP_ADD_SOURCE_MEMBERSHIP option.
//---------------------------------------------------------------------------------------------------------
class add_source_membership_v4
{
private:
    ip_mreq_source ipv4_value_{};

public:
    // Default constructor.
    // Construct with multicast address and IPv4 address specifying an interface.
    add_source_membership_v4(
        const boost::asio::ip::address_v4& multicast_address,
        const boost::asio::ip::address_v4& source_address,
        const boost::asio::ip::address_v4& network_interface = boost::asio::ip::address_v4::any())
    {
        ipv4_value_.imr_multiaddr.s_addr =
            boost::asio::detail::socket_ops::host_to_network_long(
                multicast_address.to_uint());
        ipv4_value_.imr_sourceaddr.s_addr =
            boost::asio::detail::socket_ops::host_to_network_long(
                source_address.to_uint());
        ipv4_value_.imr_interface.s_addr =
            boost::asio::detail::socket_ops::host_to_network_long(
                network_interface.to_uint());
    }

    // Returns a value suitable for passing as the level argument to POSIX setsockopt() (or equivalent).
    template <typename Protocol>
    int level(const Protocol&) const noexcept
    {
        return BOOST_ASIO_OS_DEF(IPPROTO_IP);
    }

    // Returns a value suitable for passing as the option_name argument to POSIX setsockopt() (or equivalent).
    template <typename Protocol>
    int name(const Protocol&) const noexcept
    {
        return IP_ADD_SOURCE_MEMBERSHIP;
    }

    // Returns a pointer suitable for passing as the option_value argument to POSIX setsockopt() (or equivalent).
    template <typename Protocol>
    const void* data(const Protocol&) const noexcept
    {
        return &ipv4_value_;
    }

    // Returns a value suitable for passing as the option_len argument to POSIX setsockopt() (or equivalent),
    // after appropriate integer conversion has been performed.
    template <typename Protocol>
    std::size_t size(const Protocol&) const noexcept
    {
        return sizeof(ipv4_value_);
    }
};

【讨论】：

【解决方案2】：

看起来你必须实现他们的SettableSocketOption 概念。检查现有的多播选项是如何完成的 (svn link) 可能会有所帮助。

【讨论】：

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