// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com) | |
// (C) Copyright 2004-2007 Jonathan Turkanis | |
// Distributed under the Boost Software License, Version 1.0. (See accompanying | |
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.) | |
// See http://www.boost.org/libs/iostreams for documentation. | |
// Inspired by Daryle Walker's nullbuf from his More I/O submission. | |
#ifndef BOOST_IOSTREAMS_NULL_HPP_INCLUDED | |
#define BOOST_IOSTREAMS_NULL_HPP_INCLUDED | |
#if defined(_MSC_VER) && (_MSC_VER >= 1020) | |
# pragma once | |
#endif | |
#include <boost/iostreams/categories.hpp> | |
#include <boost/iostreams/detail/ios.hpp> // openmode, streamsize. | |
#include <boost/iostreams/positioning.hpp> | |
namespace boost { namespace iostreams { | |
template<typename Ch, typename Mode> | |
class basic_null_device { | |
public: | |
typedef Ch char_type; | |
struct category | |
: public Mode, | |
public device_tag, | |
public closable_tag | |
{ }; | |
std::streamsize read(Ch*, std::streamsize) { return 0; } | |
std::streamsize write(const Ch*, std::streamsize n) { return n; } | |
std::streampos seek( stream_offset, BOOST_IOS::seekdir, | |
BOOST_IOS::openmode = | |
BOOST_IOS::in | BOOST_IOS::out ) | |
{ return -1; } | |
void close() { } | |
void close(BOOST_IOS::openmode) { } | |
}; | |
template<typename Ch> | |
struct basic_null_source : private basic_null_device<Ch, input> { | |
typedef Ch char_type; | |
typedef source_tag category; | |
using basic_null_device<Ch, input>::read; | |
using basic_null_device<Ch, input>::close; | |
}; | |
typedef basic_null_source<char> null_source; | |
typedef basic_null_source<wchar_t> wnull_source; | |
template<typename Ch> | |
struct basic_null_sink : private basic_null_device<Ch, output> { | |
typedef Ch char_type; | |
typedef sink_tag category; | |
using basic_null_device<Ch, output>::write; | |
using basic_null_device<Ch, output>::close; | |
}; | |
typedef basic_null_sink<char> null_sink; | |
typedef basic_null_sink<wchar_t> wnull_sink; | |
} } // End namespaces iostreams, boost. | |
#endif // #ifndef BOOST_IOSTREAMS_NULL_HPP_INCLUDED |