#ifndef __NULLSTREAM_H__
#define __NULLSTREAM_H__

#include <streambuf>
#include <iostream>
#include <string>

/*
 * ヌルストリーム
 * nul,/dev/nullと同じ動作
 */

template<
    class _Elem, 
    class _Traits>
class basic_NullStreambuf : public std::basic_streambuf<_Elem, _Traits> {
  protected:
    typedef std::basic_streambuf<_Elem, _Traits> super_t;
    typedef std::streamsize streamsize;
    typedef typename super_t::int_type int_type;
  public:
    basic_NullStreambuf() throw(std::ios_base::failure) : super_t() {}
    virtual ~basic_NullStreambuf() {}
  protected:
    int_type overflow(int_type c = _Traits::eof()){
      return _Traits::not_eof(c);
    }
    streamsize xsputn(const _Elem *s, streamsize n){
      return (streamsize)n;
    }
    
    streamsize xsgetn(_Elem *s, streamsize n){
      return (streamsize)0;
    }
    int_type underflow(){
      return _Traits::eof();
    }
    int_type uflow(){
      return _Traits::eof();
    }
};

typedef basic_NullStreambuf<char, std::char_traits<char> > NullStreambuf;

class NullStream : public std::iostream{
  public:
    typedef NullStreambuf buf_t;
  protected:
    typedef std::iostream super_t;
    buf_t buf;
  public:
    NullStream() throw(std::ios_base::failure) : buf(), super_t(&buf){}
    ~NullStream(){}
};

#endif /* __NULLSTREAM_H__ */