boost/iostreams/filter/stdio.hpp
// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
// (C) Copyright 2005-2007 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.
// Based on the work of Christopher Diggins.
#ifndef BOOST_IOSTREAMS_STDIO_FILTER_HPP_INCLUDED
#define BOOST_IOSTREAMS_STDIO_FILTER_HPP_INCLUDED
#if defined(_MSC_VER)
# pragma once
#endif
#include <iostream>
#include <memory> // allocator.
#include <vector>
#include <boost/iostreams/detail/config/wide_streams.hpp>
#include <boost/iostreams/detail/char_traits.hpp>
#include <boost/iostreams/detail/ios.hpp>
#include <boost/iostreams/device/array.hpp>
#include <boost/iostreams/device/back_inserter.hpp>
#include <boost/iostreams/filter/aggregate.hpp>
#include <boost/iostreams/pipeline.hpp>
#include <boost/iostreams/stream_buffer.hpp>
namespace boost { namespace iostreams {
namespace detail {
} // End namespace detail.
template<typename Ch, typename Alloc = std::allocator<Ch> >
class basic_stdio_filter : public aggregate_filter<Ch, Alloc> {
private:
typedef aggregate_filter<Ch, Alloc> base_type;
public:
typedef typename base_type::char_type char_type;
typedef typename base_type::category category;
typedef typename base_type::vector_type vector_type;
private:
static std::istream& standard_input(char*) { return std::cin; }
static std::ostream& standard_output(char*) { return std::cout; }
#ifndef BOOST_IOSTREAMS_NO_WIDE_STREAMS
static std::wistream& standard_input(wchar_t*) { return std::wcin; }
static std::wostream& standard_output(wchar_t*) { return std::wcout; }
#endif // BOOST_IOSTREAMS_NO_WIDE_STREAMS
struct scoped_redirector { // Thanks to Maxim Egorushkin.
typedef BOOST_IOSTREAMS_CHAR_TRAITS(Ch) traits_type;
typedef BOOST_IOSTREAMS_BASIC_IOS(Ch, traits_type) ios_type;
typedef BOOST_IOSTREAMS_BASIC_STREAMBUF(Ch, traits_type) streambuf_type;
scoped_redirector( ios_type& ios,
streambuf_type* newbuf )
: ios_(ios), old_(ios.rdbuf(newbuf))
{ }
~scoped_redirector() { ios_.rdbuf(old_); }
scoped_redirector& operator=(const scoped_redirector&);
ios_type& ios_;
streambuf_type* old_;
};
virtual void do_filter() = 0;
virtual void do_filter(const vector_type& src, vector_type& dest)
{
stream_buffer< basic_array_source<Ch> >
srcbuf(&src[0], &src[0] + src.size());
stream_buffer< back_insert_device<vector_type> >
destbuf(iostreams::back_inserter(dest));
scoped_redirector redirect_input(standard_input((Ch*)0), &srcbuf);
scoped_redirector redirect_output(standard_output((Ch*)0), &destbuf);
do_filter();
}
};
BOOST_IOSTREAMS_PIPABLE(basic_stdio_filter, 2)
typedef basic_stdio_filter<char> stdio_filter;
typedef basic_stdio_filter<wchar_t> wstdio_wfilter;
} } // End namespaces iostreams, boost.
#endif // #ifndef BOOST_IOSTREAMS_STDIO_FILTER_HPP_INCLUDED