ceph/src/boost/libs/iostreams/include/boost/iostreams/detail/resolve.hpp

   1 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
   2 // (C) Copyright 2003-2007 Jonathan Turkanis
   3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
   5
   6 // See http://www.boost.org/libs/iostreams for documentation.
   7
   8 #ifndef BOOST_IOSTREAMS_DETAIL_RESOLVE_HPP_INCLUDED
   9 #define BOOST_IOSTREAMS_DETAIL_RESOLVE_HPP_INCLUDED
  10
  11 #if defined(_MSC_VER)
  12 # pragma once
  13 #endif
  14
  15 #include <boost/config.hpp> // partial spec, put size_t in std.
  16 #include <cstddef>          // std::size_t.
  17 #include <boost/detail/is_incrementable.hpp>
  18 #include <boost/detail/workaround.hpp>
  19 #include <boost/iostreams/detail/adapter/mode_adapter.hpp>
  20 #include <boost/iostreams/detail/adapter/output_iterator_adapter.hpp>
  21 #include <boost/iostreams/detail/adapter/range_adapter.hpp>
  22 #include <boost/iostreams/detail/config/gcc.hpp>
  23 #include <boost/iostreams/detail/config/overload_resolution.hpp>
  24 #include <boost/iostreams/detail/config/wide_streams.hpp>
  25 #include <boost/iostreams/detail/enable_if_stream.hpp>
  26 #include <boost/iostreams/detail/is_dereferenceable.hpp>
  27 #include <boost/iostreams/detail/is_iterator_range.hpp>
  28 #include <boost/iostreams/detail/select.hpp>
  29 #include <boost/iostreams/detail/wrap_unwrap.hpp>
  30 #include <boost/iostreams/device/array.hpp>
  31 #include <boost/iostreams/traits.hpp>
  32 #include <boost/mpl/and.hpp>
  33 #include <boost/mpl/bool.hpp> // true_.
  34 #include <boost/mpl/if.hpp>
  35 #include <boost/range/iterator_range.hpp>
  36 #include <boost/type_traits/is_array.hpp>
  37
  38 // Must come last.
  39 #include <boost/iostreams/detail/config/disable_warnings.hpp> // VC7.1 C4224.
  40
  41 namespace boost { namespace iostreams { namespace detail {
  42
  43 //------------------Definition of resolve-------------------------------------//
  44
  45 #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //-------------------------//
  46
  47 template<typename Mode, typename Ch, typename T>
  48 struct resolve_traits {
  49     typedef typename
  50             mpl::if_<
  51                 boost::detail::is_incrementable<T>,
  52                 output_iterator_adapter<Mode, Ch, T>,
  53                 const T&
  54             >::type type;
  55 };
  56
  57 # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-------------------------------//
  58
  59 template<typename Mode, typename Ch, typename T>
  60 typename resolve_traits<Mode, Ch, T>::type
  61 resolve( const T& t
  62          BOOST_IOSTREAMS_DISABLE_IF_STREAM(T)
  63
  64          // I suspect that the compilers which require this workaround may
  65          // be correct, but I'm not sure why :(
  66          #if BOOST_WORKAROUND(BOOST_INTEL_CXX_VERSION, BOOST_TESTED_AT(810)) ||\
  67              BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3205)) || \
  68              BOOST_WORKAROUND(BOOST_IOSTREAMS_GCC, BOOST_TESTED_AT(400)) ||\
  69              BOOST_WORKAROUND(__IBMCPP__, BOOST_TESTED_AT(1110))
  70              /**/
  71          , typename disable_if< is_iterator_range<T> >::type* = 0
  72          #endif
  73          )
  74 {
  75     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
  76     return return_type(t);
  77 }
  78
  79 template<typename Mode, typename Ch, typename Tr>
  80 mode_adapter< Mode, std::basic_streambuf<Ch, Tr> >
  81 resolve(std::basic_streambuf<Ch, Tr>& sb)
  82 { return mode_adapter< Mode, std::basic_streambuf<Ch, Tr> >(wrap(sb)); }
  83
  84 template<typename Mode, typename Ch, typename Tr>
  85 mode_adapter< Mode, std::basic_istream<Ch, Tr> >
  86 resolve(std::basic_istream<Ch, Tr>& is)
  87 { return mode_adapter< Mode, std::basic_istream<Ch, Tr> >(wrap(is)); }
  88
  89 template<typename Mode, typename Ch, typename Tr>
  90 mode_adapter< Mode, std::basic_ostream<Ch, Tr> >
  91 resolve(std::basic_ostream<Ch, Tr>& os)
  92 { return mode_adapter< Mode, std::basic_ostream<Ch, Tr> >(wrap(os)); }
  93
  94 template<typename Mode, typename Ch, typename Tr>
  95 mode_adapter< Mode, std::basic_iostream<Ch, Tr> >
  96 resolve(std::basic_iostream<Ch, Tr>& io)
  97 { return mode_adapter< Mode, std::basic_iostream<Ch, Tr> >(wrap(io)); }
  98
  99 template<typename Mode, typename Ch, std::size_t N>
 100 array_adapter<Mode, Ch> resolve(Ch (&array)[N])
 101 { return array_adapter<Mode, Ch>(array); }
 102
 103 template<typename Mode, typename Ch, typename Iter>
 104 range_adapter< Mode, boost::iterator_range<Iter> >
 105 resolve(const boost::iterator_range<Iter>& rng)
 106 { return range_adapter< Mode, boost::iterator_range<Iter> >(rng); }
 107
 108 # else // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //---------------------//
 109
 110 template<typename Mode, typename Ch, typename T>
 111 typename resolve_traits<Mode, Ch, T>::type
 112 resolve( const T& t
 113          BOOST_IOSTREAMS_DISABLE_IF_STREAM(T)
 114          #if defined(__GNUC__)
 115          , typename disable_if< is_iterator_range<T> >::type* = 0
 116          #endif
 117          )
 118 {
 119     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
 120     return return_type(t);
 121 }
 122
 123 template<typename Mode, typename Ch>
 124 mode_adapter<Mode, std::streambuf>
 125 resolve(std::streambuf& sb)
 126 { return mode_adapter<Mode, std::streambuf>(wrap(sb)); }
 127
 128 template<typename Mode, typename Ch>
 129 mode_adapter<Mode, std::istream>
 130 resolve(std::istream& is)
 131 { return mode_adapter<Mode, std::istream>(wrap(is)); }
 132
 133 template<typename Mode, typename Ch>
 134 mode_adapter<Mode, std::ostream>
 135 resolve(std::ostream& os)
 136 { return mode_adapter<Mode, std::ostream>(wrap(os)); }
 137
 138 template<typename Mode, typename Ch>
 139 mode_adapter<Mode, std::iostream>
 140 resolve(std::iostream& io)
 141 { return mode_adapter<Mode, std::iostream>(wrap(io)); }
 142
 143 template<typename Mode, typename Ch, std::size_t N>
 144 array_adapter<Mode, Ch> resolve(Ch (&array)[N])
 145 { return array_adapter<Mode, Ch>(array); }
 146
 147 template<typename Mode, typename Ch, typename Iter>
 148 range_adapter< Mode, boost::iterator_range<Iter> >
 149 resolve(const boost::iterator_range<Iter>& rng)
 150 { return range_adapter< Mode, boost::iterator_range<Iter> >(rng); }
 151
 152 # endif // # ifndef BOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------//
 153 #else // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //----------------//
 154
 155 template<typename Mode, typename Ch, typename T>
 156 struct resolve_traits {
 157     // Note: test for is_iterator_range must come before test for output
 158     // iterator.
 159     typedef typename
 160             iostreams::select<  // Disambiguation for Tru64.
 161                 is_std_io<T>,
 162                 mode_adapter<Mode, T>,
 163                 is_iterator_range<T>,
 164                 range_adapter<Mode, T>,
 165                 is_dereferenceable<T>,
 166                 output_iterator_adapter<Mode, Ch, T>,
 167                 is_array<T>,
 168                 array_adapter<Mode, T>,
 169                 else_,
 170                 #if !BOOST_WORKAROUND(__BORLANDC__, < 0x600)
 171                     const T&
 172                 #else
 173                     T
 174                 #endif
 175             >::type type;
 176 };
 177
 178 template<typename Mode, typename Ch, typename T>
 179 typename resolve_traits<Mode, Ch, T>::type
 180 resolve(const T& t, mpl::true_)
 181 {   // Bad overload resolution.
 182     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
 183     return return_type(wrap(const_cast<T&>(t)));
 184 }
 185
 186 template<typename Mode, typename Ch, typename T>
 187 typename resolve_traits<Mode, Ch, T>::type
 188 resolve(const T& t, mpl::false_)
 189 {
 190     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
 191     return return_type(t);
 192 }
 193
 194 template<typename Mode, typename Ch, typename T>
 195 typename resolve_traits<Mode, Ch, T>::type
 196 resolve(const T& t BOOST_IOSTREAMS_DISABLE_IF_STREAM(T))
 197 { return resolve<Mode, Ch>(t, is_std_io<T>()); }
 198
 199 # if !BOOST_WORKAROUND(__BORLANDC__, < 0x600) && \
 200      !defined(__GNUC__) // ---------------------------------------------------//
 201
 202 template<typename Mode, typename Ch, typename T>
 203 typename resolve_traits<Mode, Ch, T>::type
 204 resolve(T& t, mpl::true_)
 205 {
 206     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
 207     return return_type(wrap(t));
 208 }
 209
 210 template<typename Mode, typename Ch, typename T>
 211 typename resolve_traits<Mode, Ch, T>::type
 212 resolve(T& t, mpl::false_)
 213 {
 214     typedef typename resolve_traits<Mode, Ch, T>::type return_type;
 215     return return_type(t);
 216 }
 217
 218 template<typename Mode, typename Ch, typename T>
 219 typename resolve_traits<Mode, Ch, T>::type
 220 resolve(T& t BOOST_IOSTREAMS_ENABLE_IF_STREAM(T))
 221 { return resolve<Mode, Ch>(t, is_std_io<T>()); }
 222
 223 # endif // Borland 5.x or GCC //--------------------------------//
 224 #endif // #ifndef BOOST_IOSTREAMS_BROKEN_OVERLOAD_RESOLUTION //---------------//
 225
 226 } } } // End namespaces detail, iostreams, boost.
 227
 228 #include <boost/iostreams/detail/config/enable_warnings.hpp> // VC7.1 4224.
 229
 230 #endif // BOOST_IOSTREAMS_DETAIL_RESOLVE_HPP_INCLUDED