Jeff Thompson | 86b6d64 | 2013-10-17 15:01:56 -0700 | [diff] [blame] | 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 | // |
| 9 | // Contains metafunctions char_type_of, category_of and mode_of used for |
| 10 | // deducing the i/o category and i/o mode of a model of Filter or Device. |
| 11 | // |
| 12 | // Also contains several utility metafunctions, functions and macros. |
| 13 | // |
| 14 | |
| 15 | #ifndef NDNBOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED |
| 16 | #define NDNBOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED |
| 17 | |
| 18 | #if defined(_MSC_VER) && (_MSC_VER >= 1020) |
| 19 | # pragma once |
| 20 | #endif |
| 21 | |
| 22 | #include <iosfwd> // stream types, char_traits. |
| 23 | #include <ndnboost/config.hpp> // partial spec, deduced typename. |
| 24 | #include <ndnboost/detail/workaround.hpp> |
| 25 | #include <ndnboost/iostreams/categories.hpp> |
| 26 | #include <ndnboost/iostreams/detail/bool_trait_def.hpp> |
| 27 | #include <ndnboost/iostreams/detail/config/wide_streams.hpp> |
| 28 | #include <ndnboost/iostreams/detail/is_iterator_range.hpp> |
| 29 | #include <ndnboost/iostreams/detail/select.hpp> |
| 30 | #include <ndnboost/iostreams/detail/select_by_size.hpp> |
| 31 | #include <ndnboost/iostreams/detail/wrap_unwrap.hpp> |
| 32 | #include <ndnboost/iostreams/traits_fwd.hpp> |
| 33 | #include <ndnboost/mpl/bool.hpp> |
| 34 | #include <ndnboost/mpl/eval_if.hpp> |
| 35 | #include <ndnboost/mpl/identity.hpp> |
| 36 | #include <ndnboost/mpl/int.hpp> |
| 37 | #include <ndnboost/mpl/or.hpp> |
| 38 | #if !NDNBOOST_WORKAROUND(NDNBOOST_MSVC, <= 1300) |
| 39 | # include <ndnboost/range/iterator_range.hpp> |
| 40 | # include <ndnboost/range/value_type.hpp> |
| 41 | #endif // #if NDNBOOST_WORKAROUND(NDNBOOST_MSVC, <= 1300) |
| 42 | #include <ndnboost/ref.hpp> |
| 43 | #include <ndnboost/type_traits/is_convertible.hpp> |
| 44 | |
| 45 | // Must come last. |
| 46 | #include <ndnboost/iostreams/detail/config/disable_warnings.hpp> |
| 47 | |
| 48 | namespace ndnboost { namespace iostreams { |
| 49 | |
| 50 | //----------Definitions of predicates for streams and stream buffers----------// |
| 51 | |
| 52 | #ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------------------// |
| 53 | |
| 54 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istream, std::basic_istream, 2) |
| 55 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostream, std::basic_ostream, 2) |
| 56 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_iostream, std::basic_iostream, 2) |
| 57 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_streambuf, std::basic_streambuf, 2) |
| 58 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ifstream, std::basic_ifstream, 2) |
| 59 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ofstream, std::basic_ofstream, 2) |
| 60 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_fstream, std::basic_fstream, 2) |
| 61 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_filebuf, std::basic_filebuf, 2) |
| 62 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istringstream, std::basic_istringstream, 3) |
| 63 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostringstream, std::basic_ostringstream, 3) |
| 64 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_stringstream, std::basic_stringstream, 3) |
| 65 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_stringbuf, std::basic_stringbuf, 3) |
| 66 | |
| 67 | #else // #ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-----------------------// |
| 68 | |
| 69 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_istream, std::istream, 0) |
| 70 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_ostream, std::ostream, 0) |
| 71 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_iostream, std::iostream, 0) |
| 72 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_streambuf, std::streambuf, 0) |
| 73 | |
| 74 | #endif // #ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //----------------------// |
| 75 | |
| 76 | template<typename T> |
| 77 | struct is_std_io |
| 78 | : mpl::or_< is_istream<T>, is_ostream<T>, is_streambuf<T> > |
| 79 | { }; |
| 80 | |
| 81 | template<typename T> |
| 82 | struct is_std_file_device |
| 83 | : mpl::or_< |
| 84 | is_ifstream<T>, |
| 85 | is_ofstream<T>, |
| 86 | is_fstream<T>, |
| 87 | is_filebuf<T> |
| 88 | > |
| 89 | { }; |
| 90 | |
| 91 | template<typename T> |
| 92 | struct is_std_string_device |
| 93 | : mpl::or_< |
| 94 | is_istringstream<T>, |
| 95 | is_ostringstream<T>, |
| 96 | is_stringstream<T>, |
| 97 | is_stringbuf<T> |
| 98 | > |
| 99 | { }; |
| 100 | |
| 101 | template<typename Device, typename Tr, typename Alloc> |
| 102 | struct stream; |
| 103 | |
| 104 | template<typename T, typename Tr, typename Alloc, typename Mode> |
| 105 | class stream_buffer; |
| 106 | |
| 107 | template< typename Mode, typename Ch, typename Tr, |
| 108 | typename Alloc, typename Access > |
| 109 | class filtering_stream; |
| 110 | |
| 111 | template< typename Mode, typename Ch, typename Tr, |
| 112 | typename Alloc, typename Access > |
| 113 | class wfiltering_stream; |
| 114 | |
| 115 | template< typename Mode, typename Ch, typename Tr, |
| 116 | typename Alloc, typename Access > |
| 117 | class filtering_streambuf; |
| 118 | |
| 119 | template< typename Mode, typename Ch, typename Tr, |
| 120 | typename Alloc, typename Access > |
| 121 | class filtering_wstreambuf; |
| 122 | |
| 123 | namespace detail { |
| 124 | |
| 125 | template<typename T, typename Tr> |
| 126 | class linked_streambuf; |
| 127 | |
| 128 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_boost_stream, |
| 129 | ndnboost::iostreams::stream, |
| 130 | 3 ) |
| 131 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_boost_stream_buffer, |
| 132 | ndnboost::iostreams::stream_buffer, |
| 133 | 4 ) |
| 134 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_stream_impl, |
| 135 | ndnboost::iostreams::filtering_stream, |
| 136 | 5 ) |
| 137 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_wstream_impl, |
| 138 | ndnboost::iostreams::wfiltering_stream, |
| 139 | 5 ) |
| 140 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_streambuf_impl, |
| 141 | ndnboost::iostreams::filtering_streambuf, |
| 142 | 5 ) |
| 143 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF( is_filtering_wstreambuf_impl, |
| 144 | ndnboost::iostreams::filtering_wstreambuf, |
| 145 | 5 ) |
| 146 | NDNBOOST_IOSTREAMS_BOOL_TRAIT_DEF(is_linked, linked_streambuf, 2) |
| 147 | |
| 148 | template<typename T> |
| 149 | struct is_filtering_stream |
| 150 | : mpl::or_< |
| 151 | is_filtering_stream_impl<T>, |
| 152 | is_filtering_wstream_impl<T> |
| 153 | > |
| 154 | { }; |
| 155 | |
| 156 | template<typename T> |
| 157 | struct is_filtering_streambuf |
| 158 | : mpl::or_< |
| 159 | is_filtering_streambuf_impl<T>, |
| 160 | is_filtering_wstreambuf_impl<T> |
| 161 | > |
| 162 | { }; |
| 163 | |
| 164 | template<typename T> |
| 165 | struct is_boost |
| 166 | : mpl::or_< |
| 167 | is_boost_stream<T>, |
| 168 | is_boost_stream_buffer<T>, |
| 169 | is_filtering_stream<T>, |
| 170 | is_filtering_streambuf<T> |
| 171 | > |
| 172 | { }; |
| 173 | |
| 174 | } // End namespace detail. |
| 175 | |
| 176 | //------------------Definitions of char_type_of-------------------------------// |
| 177 | |
| 178 | namespace detail { |
| 179 | |
| 180 | template<typename T> |
| 181 | struct member_char_type { typedef typename T::char_type type; }; |
| 182 | |
| 183 | } // End namespace detail. |
| 184 | |
| 185 | #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// |
| 186 | # ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //-------------------------------// |
| 187 | |
| 188 | template<typename T> |
| 189 | struct char_type_of |
| 190 | : detail::member_char_type< |
| 191 | typename detail::unwrapped_type<T>::type |
| 192 | > |
| 193 | { }; |
| 194 | |
| 195 | # else // # ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //---------------------// |
| 196 | |
| 197 | template<typename T> |
| 198 | struct char_type_of { |
| 199 | typedef typename detail::unwrapped_type<T>::type U; |
| 200 | typedef typename |
| 201 | mpl::eval_if< |
| 202 | is_std_io<U>, |
| 203 | mpl::identity<char>, |
| 204 | detail::member_char_type<U> |
| 205 | >::type type; |
| 206 | }; |
| 207 | |
| 208 | # endif // # ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES //--------------------// |
| 209 | |
| 210 | template<typename Iter> |
| 211 | struct char_type_of< iterator_range<Iter> > { |
| 212 | typedef typename iterator_value<Iter>::type type; |
| 213 | }; |
| 214 | |
| 215 | #else // #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //------------------// |
| 216 | |
| 217 | template<typename T> |
| 218 | struct char_type_of { |
| 219 | template<typename U> |
| 220 | struct get_value_type { |
| 221 | #if !NDNBOOST_WORKAROUND(NDNBOOST_MSVC, <= 1300) |
| 222 | typedef typename range_value<U>::type type; |
| 223 | #endif // #if NDNBOOST_WORKAROUND(NDNBOOST_MSVC, <= 1300) |
| 224 | }; |
| 225 | typedef typename |
| 226 | mpl::eval_if< |
| 227 | is_iterator_range<T>, |
| 228 | get_value_type<T>, |
| 229 | detail::member_char_type< |
| 230 | NDNBOOST_DEDUCED_TYPENAME detail::unwrapped_type<T>::type |
| 231 | > |
| 232 | >::type type; |
| 233 | }; |
| 234 | |
| 235 | #endif // #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// |
| 236 | |
| 237 | //------------------Definitions of category_of--------------------------------// |
| 238 | |
| 239 | namespace detail { |
| 240 | |
| 241 | template<typename T> |
| 242 | struct member_category { typedef typename T::category type; }; |
| 243 | |
| 244 | } // End namespace detail. |
| 245 | |
| 246 | template<typename T> |
| 247 | struct category_of { |
| 248 | template<typename U> |
| 249 | struct member_category { |
| 250 | typedef typename U::category type; |
| 251 | }; |
| 252 | typedef typename detail::unwrapped_type<T>::type U; |
| 253 | typedef typename |
| 254 | mpl::eval_if< |
| 255 | mpl::and_< |
| 256 | is_std_io<U>, |
| 257 | mpl::not_< detail::is_boost<U> > |
| 258 | >, |
| 259 | iostreams::select< // Disambiguation for Tru64 |
| 260 | is_filebuf<U>, filebuf_tag, |
| 261 | is_ifstream<U>, ifstream_tag, |
| 262 | is_ofstream<U>, ofstream_tag, |
| 263 | is_fstream<U>, fstream_tag, |
| 264 | is_stringbuf<U>, stringbuf_tag, |
| 265 | is_istringstream<U>, istringstream_tag, |
| 266 | is_ostringstream<U>, ostringstream_tag, |
| 267 | is_stringstream<U>, stringstream_tag, |
| 268 | is_streambuf<U>, generic_streambuf_tag, |
| 269 | is_iostream<U>, generic_iostream_tag, |
| 270 | is_istream<U>, generic_istream_tag, |
| 271 | is_ostream<U>, generic_ostream_tag |
| 272 | >, |
| 273 | detail::member_category<U> |
| 274 | >::type type; |
| 275 | }; |
| 276 | |
| 277 | // Partial specialization for reference wrappers |
| 278 | #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// |
| 279 | |
| 280 | template<typename T> |
| 281 | struct category_of< reference_wrapper<T> > |
| 282 | : category_of<T> |
| 283 | { }; |
| 284 | |
| 285 | #endif // #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// |
| 286 | |
| 287 | //------------------Definition of get_category--------------------------------// |
| 288 | |
| 289 | // |
| 290 | // Returns an object of type category_of<T>::type. |
| 291 | // |
| 292 | template<typename T> |
| 293 | inline typename category_of<T>::type get_category(const T&) |
| 294 | { typedef typename category_of<T>::type category; return category(); } |
| 295 | |
| 296 | //------------------Definition of int_type_of---------------------------------// |
| 297 | |
| 298 | template<typename T> |
| 299 | struct int_type_of { |
| 300 | #ifndef NDNBOOST_IOSTREAMS_NO_STREAM_TEMPLATES |
| 301 | typedef std::char_traits< |
| 302 | NDNBOOST_DEDUCED_TYPENAME char_type_of<T>::type |
| 303 | > traits_type; |
| 304 | typedef typename traits_type::int_type type; |
| 305 | #else |
| 306 | typedef int type; |
| 307 | #endif |
| 308 | }; |
| 309 | |
| 310 | //------------------Definition of mode_of-------------------------------------// |
| 311 | |
| 312 | namespace detail { |
| 313 | |
| 314 | template<int N> struct io_mode_impl; |
| 315 | |
| 316 | #define NDNBOOST_IOSTREAMS_MODE_HELPER(tag_, id_) \ |
| 317 | case_<id_> io_mode_impl_helper(tag_); \ |
| 318 | template<> struct io_mode_impl<id_> { typedef tag_ type; }; \ |
| 319 | /**/ |
| 320 | NDNBOOST_IOSTREAMS_MODE_HELPER(input, 1) |
| 321 | NDNBOOST_IOSTREAMS_MODE_HELPER(output, 2) |
| 322 | NDNBOOST_IOSTREAMS_MODE_HELPER(bidirectional, 3) |
| 323 | NDNBOOST_IOSTREAMS_MODE_HELPER(input_seekable, 4) |
| 324 | NDNBOOST_IOSTREAMS_MODE_HELPER(output_seekable, 5) |
| 325 | NDNBOOST_IOSTREAMS_MODE_HELPER(seekable, 6) |
| 326 | NDNBOOST_IOSTREAMS_MODE_HELPER(dual_seekable, 7) |
| 327 | NDNBOOST_IOSTREAMS_MODE_HELPER(bidirectional_seekable, 8) |
| 328 | NDNBOOST_IOSTREAMS_MODE_HELPER(dual_use, 9) |
| 329 | #undef NDNBOOST_IOSTREAMS_MODE_HELPER |
| 330 | |
| 331 | template<typename T> |
| 332 | struct io_mode_id { |
| 333 | typedef typename category_of<T>::type category; |
| 334 | NDNBOOST_SELECT_BY_SIZE(int, value, detail::io_mode_impl_helper(category())); |
| 335 | }; |
| 336 | |
| 337 | } // End namespace detail. |
| 338 | |
| 339 | template<typename T> // Borland 5.6.4 requires this circumlocution. |
| 340 | struct mode_of : detail::io_mode_impl< detail::io_mode_id<T>::value > { }; |
| 341 | |
| 342 | // Partial specialization for reference wrappers |
| 343 | #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //---------------------------// |
| 344 | |
| 345 | template<typename T> |
| 346 | struct mode_of< reference_wrapper<T> > |
| 347 | : mode_of<T> |
| 348 | { }; |
| 349 | |
| 350 | #endif // #ifndef NDNBOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION //-----------------// |
| 351 | |
| 352 | //------------------Definition of is_device, is_filter and is_direct----------// |
| 353 | |
| 354 | namespace detail { |
| 355 | |
| 356 | template<typename T, typename Tag> |
| 357 | struct has_trait_impl { |
| 358 | typedef typename category_of<T>::type category; |
| 359 | NDNBOOST_STATIC_CONSTANT(bool, value = (is_convertible<category, Tag>::value)); |
| 360 | }; |
| 361 | |
| 362 | template<typename T, typename Tag> |
| 363 | struct has_trait |
| 364 | : mpl::bool_<has_trait_impl<T, Tag>::value> |
| 365 | { }; |
| 366 | |
| 367 | } // End namespace detail. |
| 368 | |
| 369 | template<typename T> |
| 370 | struct is_device : detail::has_trait<T, device_tag> { }; |
| 371 | |
| 372 | template<typename T> |
| 373 | struct is_filter : detail::has_trait<T, filter_tag> { }; |
| 374 | |
| 375 | template<typename T> |
| 376 | struct is_direct : detail::has_trait<T, direct_tag> { }; |
| 377 | |
| 378 | //------------------Definition of NDNBOOST_IOSTREAMS_STREAMBUF_TYPEDEFS----------// |
| 379 | |
| 380 | #define NDNBOOST_IOSTREAMS_STREAMBUF_TYPEDEFS(Tr) \ |
| 381 | typedef Tr traits_type; \ |
| 382 | typedef typename traits_type::int_type int_type; \ |
| 383 | typedef typename traits_type::off_type off_type; \ |
| 384 | typedef typename traits_type::pos_type pos_type; \ |
| 385 | /**/ |
| 386 | |
| 387 | } } // End namespaces iostreams, boost. |
| 388 | |
| 389 | #include <ndnboost/iostreams/detail/config/enable_warnings.hpp> |
| 390 | |
| 391 | #endif // #ifndef NDNBOOST_IOSTREAMS_IO_TRAITS_HPP_INCLUDED |