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// (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
// (C) Copyright 2003-2007 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.
#ifndef BOOST_IOSTREAMS_DETAIL_CONCEPT_ADAPTER_HPP_INCLUDED
#define BOOST_IOSTREAMS_DETAIL_CONCEPT_ADAPTER_HPP_INCLUDED
#include <boost/config.hpp> // SFINAE.
#include <boost/iostreams/concepts.hpp>
#include <boost/iostreams/categories.hpp>
#include <boost/iostreams/detail/adapter/non_blocking_adapter.hpp>
#include <boost/iostreams/detail/call_traits.hpp>
#include <boost/iostreams/detail/char_traits.hpp>
#include <boost/iostreams/detail/dispatch.hpp>
#include <boost/iostreams/detail/error.hpp>
#include <boost/iostreams/detail/streambuf.hpp> // pubsync.
#include <boost/iostreams/detail/config/unreachable_return.hpp>
#include <boost/iostreams/device/null.hpp>
#include <boost/iostreams/traits.hpp>
#include <boost/iostreams/operations.hpp>
#include <boost/mpl/if.hpp>
#include <boost/static_assert.hpp>
#include <boost/throw_exception.hpp>
// Must come last.
#include <boost/iostreams/detail/config/disable_warnings.hpp> // MSVC.
namespace boost { namespace iostreams { namespace detail {
template<typename Category> struct device_wrapper_impl;
template<typename Category> struct flt_wrapper_impl;
template<typename T>
class concept_adapter {
private:
typedef typename detail::value_type<T>::type value_type;
typedef typename dispatch<T, input, output>::type input_tag;
typedef typename dispatch<T, output, input>::type output_tag;
typedef typename
mpl::if_<
is_device<T>,
device_wrapper_impl<input_tag>,
flt_wrapper_impl<input_tag>
>::type input_impl;
typedef typename
mpl::if_<
is_device<T>,
device_wrapper_impl<output_tag>,
flt_wrapper_impl<output_tag>
>::type output_impl;
typedef typename
mpl::if_<
is_device<T>,
device_wrapper_impl<any_tag>,
flt_wrapper_impl<any_tag>
>::type any_impl;
public:
typedef typename char_type_of<T>::type char_type;
typedef typename category_of<T>::type category;
explicit concept_adapter(const reference_wrapper<T>& ref) : t_(ref.get())
{ BOOST_STATIC_ASSERT(is_std_io<T>::value); }
explicit concept_adapter(const T& t) : t_(t)
{ BOOST_STATIC_ASSERT(!is_std_io<T>::value); }
T& operator*() { return t_; }
T* operator->() { return &t_; }
std::streamsize read(char_type* s, std::streamsize n)
{ return this->read(s, n, (basic_null_source<char_type>*) 0); }
template<typename Source>
std::streamsize read(char_type* s, std::streamsize n, Source* src)
{ return input_impl::read(t_, src, s, n); }
std::streamsize write(const char_type* s, std::streamsize n)
{ return this->write(s, n, (basic_null_sink<char_type>*) 0); }
template<typename Sink>
std::streamsize write(const char_type* s, std::streamsize n, Sink* snk)
{ return output_impl::write(t_, snk, s, n); }
std::streampos seek( stream_offset off, BOOST_IOS::seekdir way,
BOOST_IOS::openmode which )
{
return this->seek( off, way, which,
(basic_null_device<char_type, seekable>*) 0);
}
template<typename Device>
std::streampos seek( stream_offset off, BOOST_IOS::seekdir way,
BOOST_IOS::openmode which, Device* dev )
{ return any_impl::seek(t_, dev, off, way, which); }
void close(BOOST_IOS::openmode which)
{ this->close(which, (basic_null_device<char_type, seekable>*) 0); }
template<typename Device>
void close(BOOST_IOS::openmode which, Device* dev)
{ any_impl::close(t_, dev, which); }
template<typename Device>
bool flush( Device* dev )
{
bool result = any_impl::flush(t_, dev);
if (dev && dev->BOOST_IOSTREAMS_PUBSYNC() == -1)
result = false;
return result;
}
template<typename Locale> // Avoid dependency on <locale>
void imbue(const Locale& loc) { iostreams::imbue(t_, loc); }
std::streamsize optimal_buffer_size() const
{ return iostreams::optimal_buffer_size(t_); }
private:
BOOST_DELETED_FUNCTION(concept_adapter& operator=(const concept_adapter&));
value_type t_;
};
//------------------Specializations of device_wrapper_impl--------------------//
template<>
struct device_wrapper_impl<any_tag> {
template<typename Device, typename Dummy>
static std::streampos
seek( Device& dev, Dummy*, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode which )
{
typedef typename category_of<Device>::type category;
return seek(dev, off, way, which, category());
}
template<typename Device>
static std::streampos
seek( Device&, stream_offset, BOOST_IOS::seekdir,
BOOST_IOS::openmode, any_tag )
{
boost::throw_exception(cant_seek());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0)
}
template<typename Device>
static std::streampos
seek( Device& dev, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode which,
random_access )
{
return iostreams::seek(dev, off, way, which);
}
template<typename Device, typename Dummy>
static void close(Device& dev, Dummy*, BOOST_IOS::openmode which)
{ iostreams::close(dev, which); }
template<typename Device, typename Dummy>
static bool flush(Device& dev, Dummy*)
{ return iostreams::flush(dev); }
};
template<>
struct device_wrapper_impl<input> : device_wrapper_impl<any_tag> {
template<typename Device, typename Dummy>
static std::streamsize
read( Device& dev, Dummy*, typename char_type_of<Device>::type* s,
std::streamsize n )
{ return iostreams::read(dev, s, n); }
template<typename Device, typename Dummy>
static std::streamsize
write( Device&, Dummy*, const typename char_type_of<Device>::type*,
std::streamsize )
{ boost::throw_exception(cant_write());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0) }
};
template<>
struct device_wrapper_impl<output> {
template<typename Device, typename Dummy>
static std::streamsize
read(Device&, Dummy*, typename char_type_of<Device>::type*, std::streamsize)
{ boost::throw_exception(cant_read());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0) }
template<typename Device, typename Dummy>
static std::streamsize
write( Device& dev, Dummy*, const typename char_type_of<Device>::type* s,
std::streamsize n )
{ return iostreams::write(dev, s, n); }
};
//------------------Specializations of flt_wrapper_impl--------------------//
template<>
struct flt_wrapper_impl<any_tag> {
template<typename Filter, typename Device>
static std::streampos
seek( Filter& f, Device* dev, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode which )
{
typedef typename category_of<Filter>::type category;
return seek(f, dev, off, way, which, category());
}
template<typename Filter, typename Device>
static std::streampos
seek( Filter&, Device*, stream_offset,
BOOST_IOS::seekdir, BOOST_IOS::openmode, any_tag )
{ boost::throw_exception(cant_seek());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0) }
template<typename Filter, typename Device>
static std::streampos
seek( Filter& f, Device* dev, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode which,
random_access tag )
{
typedef typename category_of<Filter>::type category;
return seek(f, dev, off, way, which, tag, category());
}
template<typename Filter, typename Device>
static std::streampos
seek( Filter& f, Device* dev, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode,
random_access, any_tag )
{ return f.seek(*dev, off, way); }
template<typename Filter, typename Device>
static std::streampos
seek( Filter& f, Device* dev, stream_offset off,
BOOST_IOS::seekdir way, BOOST_IOS::openmode which,
random_access, two_sequence )
{ return f.seek(*dev, off, way, which); }
template<typename Filter, typename Device>
static void close(Filter& f, Device* dev, BOOST_IOS::openmode which)
{ iostreams::close(f, *dev, which); }
template<typename Filter, typename Device>
static bool flush(Filter& f, Device* dev)
{ return iostreams::flush(f, *dev); }
};
template<>
struct flt_wrapper_impl<input> {
template<typename Filter, typename Source>
static std::streamsize
read( Filter& f, Source* src, typename char_type_of<Filter>::type* s,
std::streamsize n )
{ return iostreams::read(f, *src, s, n); }
template<typename Filter, typename Sink>
static std::streamsize
write( Filter&, Sink*, const typename char_type_of<Filter>::type*,
std::streamsize )
{ boost::throw_exception(cant_write());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0) }
};
template<>
struct flt_wrapper_impl<output> {
template<typename Filter, typename Source>
static std::streamsize
read(Filter&, Source*, typename char_type_of<Filter>::type*,std::streamsize)
{ boost::throw_exception(cant_read());
BOOST_IOSTREAMS_UNREACHABLE_RETURN(0) }
template<typename Filter, typename Sink>
static std::streamsize
write( Filter& f, Sink* snk, const typename char_type_of<Filter>::type* s,
std::streamsize n )
{ return iostreams::write(f, *snk, s, n); }
};
//----------------------------------------------------------------------------//
} } } // End namespaces detail, iostreams, boost.
#include <boost/iostreams/detail/config/enable_warnings.hpp> // MSVC.
#endif // #ifndef BOOST_IOSTREAMS_DETAIL_CONCEPT_ADAPTER_HPP_INCLUDED