继承自 std：：basic_streambuf 以写入套接字

问：

我想编写一个我自己的日志库，为日志条目发送到的任何地方提供抽象。

C++ 的 IO 库已经提供了这种抽象，带有 和 。我还希望能够从套接字读/写。std::stringstreamstd::fstream

我读到扩展标准库的正确方法是继承 .我不明白的是，如果从 like 继承，哪里需要 和 类？我不能将某个流的缓冲区替换为子类的实例，该子类的子类输出到我想要的位置吗？std::basic_streambufstd::basic_streambufstd::basic_filebufstd::ifsreamstd::ofstreamstd::fstreamstd::basic_streambuf

到目前为止，我已经做了以下工作，但我真的不确定我在做什么。以下设计是否正确？

template< typename char_type, typename traits_type = std::char_traits< char_type > >
class basic_sock_streambuf : public std::basic_streambuf< char_type, traits_type >
{
public:

    basic_sock_streambuf()
    {

    }

    ~basic_sock_streambuf()
    {

    }

    int overflow (int c = EOF)
    {
        fputc( c, stdout ); // Temporary.
        return traits_type::to_int_type( c );
    }

    int underflow()
    {
        return fgetc( stdout ); // Temporary.
    }

    int sync()
    {
        return 0;
    }
};

template< typename char_type, typename traits_type = std::char_traits< char_type > >
class basic_isockstream : public std::basic_istream< char_type, traits_type >
{
};

template< typename char_type, typename traits_type = std::char_traits< char_type > >
class basic_osockstream : public std::basic_ostream< char_type, traits_type >
{
};

template< typename char_type, typename traits_type = std::char_traits< char_type > >
class basic_socktream : public basic_isockstream< char_type, traits_type >, public basic_osockstream< char_type, traits_type >
{
private:

    typedef basic_isockstream< char_type, traits_type > iparent;

    typedef basic_osockstream< char_type, traits_type > oparent;

    basic_sock_streambuf< char_type, traits_type > sock_sb;

    std::basic_streambuf< char_type, traits_type > * old_isb;

    std::basic_streambuf< char_type, traits_type > * old_osb;

public:

    basic_socktream()
    {
        old_isb = iparent::rdbuf( & sock_sb );
        old_osb = oparent::rdbuf( & sock_sb );
    }

    ~basic_socktream() throw()
    {
        iparent::rdbuf( old_isb );
        oparent::rdbuf( old_osb );
    }
};

编辑：根据答案更新代码：

template<
    typename char_type,
    typename traits_type = std::char_traits< char_type > >
class basic_sockbuf :
    public std::basic_streambuf< char_type, traits_type >
{
public:

    basic_sockbuf()
    {
    }

    ~basic_sockbuf()
    {
    }

    int overflow( int c = EOF )
    {
        fputc( c, stdout ); // Temporary.
        return traits_type::to_int_type( c );
    }

    int underflow()
    {
        return fgetc( stdout ); // Temporary.
    }

    int sync()
    {
        return 0;
    }
};

template<
    typename char_type,
    typename traits_type = std::char_traits< char_type > >
class basic_isockstream :
    public std::basic_istream< char_type, traits_type >
{
private:

    typedef std::basic_istream< char_type, traits_type > parent;

    basic_sockbuf< char_type, traits_type > buffer;

public:

    basic_isockstream() :
        std::basic_istream< char_type, traits_type >::basic_istream(),
        buffer()
    {
        init( & buffer );
    }
};

template<
    typename char_type,
    typename traits_type = std::char_traits< char_type > >
class basic_osockstream :
    public std::basic_ostream< char_type, traits_type >
{
private:

    basic_sockbuf< char_type, traits_type > buffer;

public:

    basic_osockstream() :
        std::basic_ostream< char_type, traits_type >::basic_istream(),
        buffer()
    {
        init( & buffer );
    }
};

template<
    typename char_type,
    typename traits_type = std::char_traits< char_type > >
class basic_socktream :
    public std::basic_iostream< char_type, traits_type >,
    public basic_sockbuf< char_type, traits_type >
{
private:

    basic_sockbuf< char_type, traits_type > buffer;

public:

    basic_socktream() :
        std::basic_iostream< char_type, traits_type >::basic_iostream(),
        buffer()
    {
        std::basic_iostream< char_type, traits_type >::init( & buffer );
    }
};