ossrv_pub/boost_apis/boost/iostreams/compose.hpp
changeset 31 ce057bb09d0b
parent 0 e4d67989cc36
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ossrv_pub/boost_apis/boost/iostreams/compose.hpp	Fri Jun 04 16:20:51 2010 +0100
@@ -0,0 +1,368 @@
+// (C) Copyright Jonathan Turkanis 2005.
+// 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.
+
+// Note: bidirectional streams are not supported.
+
+#ifndef BOOST_IOSTREAMS_COMPOSE_HPP_INCLUDED
+#define BOOST_IOSTREAMS_COMPOSE_HPP_INCLUDED
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1020)
+# pragma once
+#endif
+
+#include <algorithm>          // min.
+#include <utility>            // pair.
+#include <boost/config.hpp>   // DEDUCED_TYPENAME.
+#include <boost/iostreams/categories.hpp>
+#include <boost/iostreams/detail/adapter/direct_adapter.hpp>
+#include <boost/iostreams/detail/call_traits.hpp>
+#include <boost/iostreams/detail/closer.hpp>
+#include <boost/iostreams/detail/enable_if_stream.hpp>
+#include <boost/iostreams/operations.hpp>
+#include <boost/iostreams/traits.hpp>      // mode_of, is_direct.
+#include <boost/mpl/if.hpp>
+#include <boost/ref.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/type_traits/is_convertible.hpp>
+
+namespace boost { namespace iostreams {
+
+namespace detail {
+
+template<typename Filter, typename Device>
+struct composite_mode {
+    typedef typename mode_of<Filter>::type           filter_mode;
+    typedef typename mode_of<Device>::type           device_mode;
+    typedef is_convertible<filter_mode, dual_use>    is_dual_use;
+    typedef typename
+            mpl::if_<
+                is_convertible<device_mode, input>,
+                input,
+                output
+            >::type                                  type;
+};
+
+//
+// Template name: composite_device.
+// Description: Provides a Device view of a Filter, Device pair.
+// Template paramters:
+//      Filter - A model of Filter.
+//      Device - An indirect model of Device.
+//
+template< typename Filter,
+          typename Device,
+          typename Mode =
+              BOOST_DEDUCED_TYPENAME composite_mode<Filter, Device>::type >
+class composite_device {
+private:
+    typedef typename detail::param_type<Device>::type       param_type;
+    typedef typename
+            iostreams::select<  // Disambiguation for Tru64.
+                is_direct<Device>,  direct_adapter<Device>,
+                is_std_io<Device>,  Device&,
+                else_,              Device
+            >::type                                         value_type;
+public:
+    typedef typename char_type_of<Filter>::type             char_type;
+    struct category
+        : Mode,
+          device_tag,
+          closable_tag,
+          flushable_tag,
+          localizable_tag,
+          optimally_buffered_tag
+        { };
+    composite_device(const Filter& flt, param_type dev);
+    std::streamsize read(char_type* s, std::streamsize n);
+    std::streamsize write(const char_type* s, std::streamsize n);
+    stream_offset seek( stream_offset off, BOOST_IOS::seekdir way,
+                        BOOST_IOS::openmode which =
+                            BOOST_IOS::in | BOOST_IOS::out );
+
+    void close();
+    void close(BOOST_IOS::openmode which);
+    bool flush();
+    std::streamsize optimal_buffer_size() const;
+
+    template<typename Locale> // Avoid dependency on <locale>
+    void imbue(const Locale& loc)
+    {
+        iostreams::imbue(filter_, loc);
+        iostreams::imbue(device_, loc);
+    }
+
+    Filter& first() { return filter_; }
+    Device& second() { return device_; }
+private:
+    Filter      filter_;
+    value_type  device_;
+};
+
+//
+// Template name: composite_device.
+// Description: Provides a Device view of a Filter, Device pair.
+// Template paramters:
+//      Filter - A model of Filter.
+//      Device - An indirect model of Device.
+//
+template<typename Filter1, typename Filter2>
+class composite_filter {
+private:
+     typedef reference_wrapper<Filter2>           filter_ref;
+public:
+    typedef typename char_type_of<Filter1>::type  char_type;
+    struct category
+        : mode_of<Filter1>::type,
+          filter_tag,
+          multichar_tag,
+          closable_tag,
+          flushable_tag,
+          localizable_tag,
+          optimally_buffered_tag
+        { };
+    composite_filter(const Filter1& filter1, const Filter2& filter2)
+        : filter1_(filter1), filter2_(filter2)
+        { }
+
+    template<typename Source>
+    std::streamsize read(Source& src, char_type* s, std::streamsize n)
+    {
+        composite_device<filter_ref, Source> cmp(boost::ref(filter2_), src);
+        return iostreams::read(filter1_, cmp, s, n);
+    }
+
+    template<typename Sink>
+    std::streamsize write(Sink& snk, const char_type* s, std::streamsize n)
+    {
+        composite_device<filter_ref, Sink> cmp(boost::ref(filter2_), snk);
+        return iostreams::write(filter1_, cmp, s, n);
+    }
+
+    template<typename Device>
+    stream_offset seek( Device& dev, stream_offset off, BOOST_IOS::seekdir way,
+                        BOOST_IOS::openmode which =
+                            BOOST_IOS::in | BOOST_IOS::out )
+    {
+        composite_device<filter_ref, Device> cmp(boost::ref(filter2_), dev);
+        return iostreams::seek(filter1_, cmp, off, way, which);
+    }
+
+    template<typename Device>
+    void close( Device& dev,
+                BOOST_IOS::openmode which =
+                    BOOST_IOS::in | BOOST_IOS::out )
+    {
+        composite_device<filter_ref, Device> cmp(boost::ref(filter2_), dev);
+        iostreams::close(filter1_, cmp, which);
+    }
+
+    template<typename Device>
+    bool flush(Device& dev)
+    {
+        composite_device<Filter2, Device> cmp(filter2_, dev);
+        return iostreams::flush(filter1_, cmp);
+    }
+
+    std::streamsize optimal_buffer_size() const
+    {
+        std::streamsize first = iostreams::optimal_buffer_size(filter1_);
+        std::streamsize second = iostreams::optimal_buffer_size(filter2_);
+        return first < second ? second : first;
+    }
+
+    template<typename Locale> // Avoid dependency on <locale>
+    void imbue(const Locale& loc)
+    {   // To do: consider using RAII.
+        iostreams::imbue(filter1_, loc);
+        iostreams::imbue(filter2_, loc);
+    }
+
+    Filter1& first() { return filter1_; }
+    Filter2& second() { return filter2_; }
+private:
+    Filter1  filter1_;
+    Filter2  filter2_;
+};
+
+template<typename Filter, typename FilterOrDevice>
+struct composite_traits
+    : mpl::if_<
+          is_device<FilterOrDevice>,
+          composite_device<Filter, FilterOrDevice>,
+          composite_filter<Filter, FilterOrDevice>
+      >
+    { };
+
+} // End namespace detail.
+
+template<typename Filter, typename FilterOrDevice>
+struct composite : detail::composite_traits<Filter, FilterOrDevice>::type {
+    typedef typename detail::param_type<FilterOrDevice>::type param_type;
+    typedef typename detail::composite_traits<Filter, FilterOrDevice>::type base;
+    composite(const Filter& flt, param_type dev)
+        : base(flt, dev)
+        { }
+};
+
+//--------------Implementation of compose-------------------------------------//
+
+// Note: The following workarounds are patterned after resolve.hpp. It has not
+// yet been confirmed that they are necessary.
+
+#ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //-------------------------//
+# ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-------------------------------//
+
+template<typename Filter, typename FilterOrDevice>
+composite<Filter, FilterOrDevice>
+compose( const Filter& filter, const FilterOrDevice& fod
+         BOOST_IOSTREAMS_DISABLE_IF_STREAM(FilterOrDevice) )
+{ return composite<Filter, FilterOrDevice>(filter, fod); }
+
+template<typename Filter, typename Ch, typename Tr>
+composite< Filter, std::basic_streambuf<Ch, Tr> >
+compose(const Filter& filter, std::basic_streambuf<Ch, Tr>& sb)
+{ return composite< Filter, std::basic_streambuf<Ch, Tr> >(filter, sb); }
+
+template<typename Filter, typename Ch, typename Tr>
+composite< Filter, std::basic_istream<Ch, Tr> >
+compose(const Filter& filter, std::basic_istream<Ch, Tr>& is)
+{ return composite< Filter, std::basic_istream<Ch, Tr> >(filter, is); }
+
+template<typename Filter, typename Ch, typename Tr>
+composite< Filter, std::basic_ostream<Ch, Tr> >
+compose(const Filter& filter, std::basic_ostream<Ch, Tr>& os)
+{ return composite< Filter, std::basic_ostream<Ch, Tr> >(filter, os); }
+
+template<typename Filter, typename Ch, typename Tr>
+composite< Filter, std::basic_iostream<Ch, Tr> >
+compose(const Filter& filter, std::basic_iostream<Ch, Tr>& io)
+{ return composite< Filter, std::basic_iostream<Ch, Tr> >(filter, io); }
+
+# else // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //---------------------//
+
+template<typename Filter, typename FilterOrDevice>
+composite<Filter, FilterOrDevice>
+compose( const Filter& filter, const FilterOrDevice& fod
+         BOOST_IOSTREAMS_DISABLE_IF_STREAM(FilterOrDevice) )
+{ return composite<Filter, FilterOrDevice>(filter, fod); }
+
+template<typename Filter>
+composite<Filter, std::streambuf>
+compose(const Filter& filter, std::streambuf& sb)
+{ return composite<Filter, std::streambuf>(filter, sb); }
+
+template<typename Filter>
+composite<Filter, std::istream>
+compose(const Filter& filter, std::istream& is)
+{ return composite<Filter, std::istream>(filter, is); }
+
+template<typename Filter>
+composite<Filter, std::ostream>
+compose(const Filter& filter, std::ostream& os)
+{ return composite<Filter, std::ostream>(filter, os); }
+
+template<typename Filter>
+composite<Filter, std::iostream>
+compose(const Filter& filter, std::iostream& io)
+{ return composite<Filter, std::iostream>(filter, io); }
+
+# endif // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------//
+#else // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //----------------//
+
+template<typename Filter, typename Stream>
+composite<Filter, Stream>
+compose(const Filter& flt, const Stream& strm, mpl::true_)
+{   // Bad overload resolution.
+    return composite<Filter, Stream>(flt, const_cast<Stream&>(strm));
+}
+
+template<typename Filter, typename FilterOrDevice>
+composite<Filter, FilterOrDevice>
+compose(const Filter& flt, const FilterOrDevice& fod, mpl::false_)
+{ return composite<Filter, FilterOrDevice>(flt, fod); }
+
+template<typename Filter, typename FilterOrDevice>
+composite<Filter, FilterOrDevice>
+compose( const Filter& flt, const FilterOrDevice& fod
+         BOOST_IOSTREAMS_DISABLE_IF_STREAM(T) )
+{ return compose(flt, fod, is_std_io<FilterOrDevice>()); }
+
+# if !BOOST_WORKAROUND(__BORLANDC__, < 0x600) && \
+     !BOOST_WORKAROUND(BOOST_MSVC, <= 1300) && \
+     !defined(__GNUC__) // ---------------------------------------------------//
+
+template<typename Filter, typename FilterOrDevice>
+composite<Filter, FilterOrDevice>
+compose (const Filter& filter, FilterOrDevice& fod)
+{ return composite<Filter, FilterOrDevice>(filter, fod); }
+
+# endif // Borland 5.x, VC6-7.0 or GCC 2.9x //--------------------------------//
+#endif // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //---------------//
+
+//----------------------------------------------------------------------------//
+
+namespace detail {
+
+//--------------Implementation of composite_device---------------------------//
+
+template<typename Filter, typename Device, typename Mode>
+composite_device<Filter, Device, Mode>::composite_device
+    (const Filter& flt, param_type dev)
+    : filter_(flt), device_(dev)
+    { }
+
+template<typename Filter, typename Device, typename Mode>
+inline std::streamsize composite_device<Filter, Device, Mode>::read
+    (char_type* s, std::streamsize n)
+{ return iostreams::read(filter_, device_, s, n); }
+
+template<typename Filter, typename Device, typename Mode>
+inline std::streamsize composite_device<Filter, Device, Mode>::write
+    (const char_type* s, std::streamsize n)
+{ return iostreams::write(filter_, device_, s, n); }
+
+template<typename Filter, typename Device, typename Mode>
+stream_offset composite_device<Filter, Device, Mode>::seek
+    (stream_offset off, BOOST_IOS::seekdir way, BOOST_IOS::openmode which)
+{ return iostreams::seek(filter_, device_, off, way, which); }
+
+template<typename Filter, typename Device, typename Mode>
+void composite_device<Filter, Device, Mode>::close()
+{
+    typedef typename mode_of<Device>::type device_mode;
+    BOOST_IOS::openmode which =
+        is_convertible<device_mode, input>() ?
+            BOOST_IOS::in :
+            BOOST_IOS::out;
+    close(which);
+}
+
+template<typename Filter, typename Device, typename Mode>
+void composite_device<Filter, Device, Mode>::close(BOOST_IOS::openmode which)
+{
+    bool                                 nothrow = false;
+    external_closer<value_type>          close_device(device_, which, nothrow);
+    external_closer<Filter, value_type>  close_filter(filter_, device_, which, nothrow);
+}
+
+template<typename Filter, typename Device, typename Mode>
+bool composite_device<Filter, Device, Mode>::flush()
+{   // To do: consider using RAII.
+    bool r1 = iostreams::flush(filter_, device_);
+    bool r2 = iostreams::flush(device_);
+    return r1 && r2;
+}
+
+template<typename Filter, typename Device, typename Mode>
+std::streamsize
+composite_device<Filter, Device, Mode>::optimal_buffer_size() const
+{ return iostreams::optimal_buffer_size(device_); }
+
+} // End namespace detail.
+
+} } // End namespaces iostreams, boost.
+
+#endif // #ifndef BOOST_IOSTREAMS_COMPOSE_HPP_INCLUDED