| // (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. |
| |
| // 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/enable_if_stream.hpp> |
| #include <boost/iostreams/detail/execute.hpp> |
| #include <boost/iostreams/detail/functional.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> |
| |
| // Must come last. |
| #include <boost/iostreams/detail/config/disable_warnings.hpp> // MSVC. |
| |
| namespace boost { namespace iostreams { |
| |
| namespace detail { |
| |
| template< typename First, |
| typename Second, |
| typename FirstMode = |
| BOOST_DEDUCED_TYPENAME mode_of<First>::type, |
| typename SecondMode = |
| BOOST_DEDUCED_TYPENAME mode_of<Second>::type > |
| struct composite_mode |
| : select< |
| is_convertible<SecondMode, FirstMode>, FirstMode, |
| is_convertible<FirstMode, SecondMode>, SecondMode, |
| is_convertible<SecondMode, input>, input, |
| else_, output |
| > |
| { }; |
| |
| // |
| // 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 mode_of<Filter>::type filter_mode; |
| typedef typename mode_of<Device>::type device_mode; |
| 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); |
| std::streampos 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, |
| typename Mode = |
| BOOST_DEDUCED_TYPENAME composite_mode<Filter1, Filter2>::type > |
| class composite_filter { |
| private: |
| typedef reference_wrapper<Filter2> filter_ref; |
| typedef typename mode_of<Filter1>::type first_mode; |
| typedef typename mode_of<Filter2>::type second_mode; |
| |
| // A dual-use filter cannot be composed with a read-write filter |
| BOOST_STATIC_ASSERT( |
| !(is_convertible<first_mode, dual_use>::value) || |
| !(is_convertible<second_mode, input>::value) || |
| !(is_convertible<second_mode, output>::value) || |
| (is_convertible<second_mode, dual_use>::value) |
| ); |
| BOOST_STATIC_ASSERT( |
| !(is_convertible<second_mode, dual_use>::value) || |
| !(is_convertible<first_mode, input>::value) || |
| !(is_convertible<first_mode, output>::value) || |
| (is_convertible<first_mode, dual_use>::value) |
| ); |
| public: |
| typedef typename char_type_of<Filter1>::type char_type; |
| struct category |
| : Mode, |
| 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> |
| std::streampos 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_STATIC_ASSERT((!is_convertible<category, two_sequence>::value)); |
| BOOST_STATIC_ASSERT((!is_convertible<category, dual_use>::value)); |
| |
| // Create a new device by composing the second filter2_ with dev. |
| composite_device<filter_ref, Device> cmp(boost::ref(filter2_), dev); |
| |
| // Close input sequences in reverse order and output sequences in |
| // forward order |
| if (!is_convertible<first_mode, dual_use>::value) { |
| detail::execute_all( |
| detail::call_close(filter2_, dev, BOOST_IOS::in), |
| detail::call_close(filter1_, cmp, BOOST_IOS::in), |
| detail::call_close(filter1_, cmp, BOOST_IOS::out), |
| detail::call_close(filter2_, dev, BOOST_IOS::out) |
| ); |
| } else if (is_convertible<second_mode, input>::value) { |
| detail::execute_all( |
| detail::call_close(filter2_, dev, BOOST_IOS::in), |
| detail::call_close(filter1_, cmp, BOOST_IOS::in) |
| ); |
| } else { |
| detail::execute_all( |
| detail::call_close(filter1_, cmp, BOOST_IOS::out), |
| detail::call_close(filter2_, dev, BOOST_IOS::out) |
| ); |
| } |
| } |
| |
| template<typename Device> |
| void close(Device& dev, BOOST_IOS::openmode which) |
| { |
| BOOST_STATIC_ASSERT( |
| (is_convertible<category, two_sequence>::value) || |
| (is_convertible<category, dual_use>::value) |
| ); |
| |
| // Create a new device by composing the second filter2_ with dev. |
| composite_device<filter_ref, Device> cmp(boost::ref(filter2_), dev); |
| |
| // Close input sequences in reverse order |
| if ( which == BOOST_IOS::in && |
| ( !is_convertible<first_mode, dual_use>::value || |
| is_convertible<second_mode, input>::value ) ) |
| { |
| detail::execute_all( |
| detail::call_close(filter2_, dev, BOOST_IOS::in), |
| detail::call_close(filter1_, cmp, BOOST_IOS::in) |
| ); |
| } |
| |
| // Close output sequences in forward order |
| if ( which == BOOST_IOS::out && |
| ( !is_convertible<first_mode, dual_use>::value || |
| is_convertible<second_mode, output>::value ) ) |
| { |
| detail::execute_all( |
| detail::call_close(filter1_, cmp, BOOST_IOS::out), |
| detail::call_close(filter2_, dev, BOOST_IOS::out) |
| ); |
| } |
| } |
| |
| 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> |
| std::streampos 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() |
| { |
| BOOST_STATIC_ASSERT((!is_convertible<Mode, two_sequence>::value)); |
| BOOST_STATIC_ASSERT( |
| !(is_convertible<filter_mode, dual_use>::value) || |
| !(is_convertible<device_mode, input>::value) || |
| !(is_convertible<device_mode, output>::value) |
| ); |
| |
| // Close input sequences in reverse order and output sequences |
| // in forward order |
| if (!is_convertible<filter_mode, dual_use>::value) { |
| detail::execute_all( |
| detail::call_close(device_, BOOST_IOS::in), |
| detail::call_close(filter_, device_, BOOST_IOS::in), |
| detail::call_close(filter_, device_, BOOST_IOS::out), |
| detail::call_close(device_, BOOST_IOS::out) |
| ); |
| } else if (is_convertible<device_mode, input>::value) { |
| detail::execute_all( |
| detail::call_close(device_, BOOST_IOS::in), |
| detail::call_close(filter_, device_, BOOST_IOS::in) |
| ); |
| } else { |
| detail::execute_all( |
| detail::call_close(filter_, device_, BOOST_IOS::out), |
| detail::call_close(device_, BOOST_IOS::out) |
| ); |
| } |
| } |
| |
| template<typename Filter, typename Device, typename Mode> |
| void composite_device<Filter, Device, Mode>::close(BOOST_IOS::openmode which) |
| { |
| BOOST_STATIC_ASSERT((is_convertible<Mode, two_sequence>::value)); |
| BOOST_STATIC_ASSERT(!(is_convertible<filter_mode, dual_use>::value)); |
| |
| // Close input sequences in reverse order |
| if (which == BOOST_IOS::in) { |
| detail::execute_all( |
| detail::call_close(device_, BOOST_IOS::in), |
| detail::call_close(filter_, device_, BOOST_IOS::in) |
| ); |
| } |
| |
| // Close output sequences in forward order |
| if (which == BOOST_IOS::out) { |
| detail::execute_all( |
| detail::call_close(filter_, device_, BOOST_IOS::out), |
| detail::call_close(device_, BOOST_IOS::out) |
| ); |
| } |
| } |
| |
| template<typename Filter, typename Device, typename Mode> |
| bool composite_device<Filter, Device, Mode>::flush() |
| { |
| 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. |
| |
| #include <boost/iostreams/detail/config/enable_warnings.hpp> |
| |
| #endif // #ifndef BOOST_IOSTREAMS_COMPOSE_HPP_INCLUDED |
