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File indexing completed on 2024-04-06 12:02:32
0001 /*****************************************************************************/ 0002 /** 0003 * \file portable_iarchive.hpp 0004 * \brief Provides an archive to read from portable binary files. 0005 * \author christian.pfligersdorffer@gmx.at 0006 * \version 5.1 0007 * 0008 * This pair of archives brings the advantages of binary streams to the cross 0009 * platform boost::serialization user. While being almost as fast as the native 0010 * binary archive it allows its files to be exchanged between cpu architectures 0011 * using different byte order (endianness). Speaking of speed: in serializing 0012 * numbers the (portable) binary approach is approximately ten times faster than 0013 * the ascii implementation (that is inherently portable)! 0014 * 0015 * Based on the portable archive example by Robert Ramey this implementation 0016 * uses Beman Dawes endian library and fp_utilities from Johan Rade, both being 0017 * in boost since 1.36. Prior to that you need to add them both (header only) 0018 * to your boost directory before you're able to use the archives provided. 0019 * Our archives have been tested successfully for boost versions 1.33 to 1.49! 0020 * 0021 * \note Correct behaviour has so far been confirmed using PowerPC-32, x86-32 0022 * and x86-64 platforms featuring different byte order. So there is a good 0023 * chance it will instantly work for your specific setup. If you encounter 0024 * problems or have suggestions please contact the author. 0025 * 0026 * \note Version 5.1 is now compatible with boost up to version 1.59. Thanks to 0027 * ecotax for pointing to the issue with shared_ptr_helper. 0028 * 0029 * \note Version 5.0 is now compatible with boost up to version 1.49 and enables 0030 * serialization of std::wstring by converting it to/from utf8 (thanks to 0031 * Arash Abghari for this suggestion). With that all unit tests from the 0032 * serialization library pass again with the notable exception of user 0033 * defined primitive types. Those are not supported and as a result any 0034 * user defined type to be used with the portable archives are required 0035 * to be at least object_serializable. 0036 * 0037 * \note Version 4.2 maintains compatibility with the latest boost 1.45 and adds 0038 * serialization of special floating point values inf and NaN as proposed 0039 * by Francois Mauger. 0040 * 0041 * \note Version 4.1 makes the archives work together with boost 1.40 and 1.41. 0042 * Thanks to Francois Mauger for his suggestions. 0043 * 0044 * \note Version 4 removes one level of the inheritance hierarchy and directly 0045 * builds upon binary primitive and basic binary archive, thereby fixing 0046 * the last open issue regarding array serialization. Thanks to Robert 0047 * Ramey for the hint. 0048 * 0049 * \note A few fixes introduced in version 3.1 let the archives pass all of the 0050 * serialization tests. Thanks to Sergey Morozov for running the tests. 0051 * Wouter Bijlsma pointed out where to find the fp_utilities and endian 0052 * libraries headers inside the boost distribution. I would never have 0053 * found them so thank him it works out of the box since boost 1.36. 0054 * 0055 * \note With Version 3.0 the archives have been made portable across different 0056 * boost versions. For that purpose a header is added to the data that 0057 * supplies the underlying serialization library version. Backwards 0058 * compatibility is maintained by assuming library version boost 1.33 if 0059 * the iarchive is created using the no_header flag. Whether a header is 0060 * present or not can be guessed by peeking into the stream: the header's 0061 * first byte is the magic number 127 coinciding with 'e'|'o'|'s' :-) 0062 * 0063 * \note Version 2.1 removes several compiler warnings and enhances floating 0064 * point diagnostics to inform the user if some preconditions are violated 0065 * on his platform. We do not strive for the universally portable solution 0066 * in binary floating point serialization as desired by some boost users. 0067 * Instead we support only the most widely used IEEE 754 format and try to 0068 * detect when requirements are not met and hence our approach must fail. 0069 * Contributions we made by Johan Rade and Ákos Maróy. 0070 * 0071 * \note Version 2.0 fixes a serious bug that effectively transformed most 0072 * of negative integral values into positive values! For example the two 0073 * numbers -12 and 234 were stored in the same 8-bit pattern and later 0074 * always restored to 234. This was fixed in this version in a way that 0075 * does not change the interpretation of existing archives that did work 0076 * because there were no negative numbers. The other way round archives 0077 * created by version 2.0 and containing negative numbers will raise an 0078 * integer type size exception when reading it with version 1.0. Thanks 0079 * to Markus Frohnmaier for testing the archives and finding the bug. 0080 * 0081 * \copyright The boost software license applies. 0082 */ 0083 /*****************************************************************************/ 0084 0085 #ifndef CondFormats_Serialization_portable_iarchive_hpp 0086 #define CondFormats_Serialization_portable_iarchive_hpp 0087 0088 #include <istream> 0089 0090 // basic headers 0091 #include <boost/version.hpp> 0092 #include <boost/utility/enable_if.hpp> 0093 #include <boost/archive/basic_binary_iprimitive.hpp> 0094 #include <boost/archive/basic_binary_iarchive.hpp> 0095 0096 #if BOOST_VERSION >= 103500 && BOOST_VERSION < 105600 0097 #include <boost/archive/shared_ptr_helper.hpp> 0098 #endif 0099 0100 // funny polymorphics 0101 #if BOOST_VERSION < 103500 0102 #include <boost/archive/detail/polymorphic_iarchive_impl.hpp> 0103 #define POLYMORPHIC(T) boost::archive::detail::polymorphic_iarchive_impl<T> 0104 0105 #elif BOOST_VERSION < 103600 0106 #include <boost/archive/detail/polymorphic_iarchive_dispatch.hpp> 0107 #define POLYMORPHIC(T) boost::archive::detail::polymorphic_iarchive_dispatch<T> 0108 0109 #else 0110 #include <boost/archive/detail/polymorphic_iarchive_route.hpp> 0111 #define POLYMORPHIC(T) boost::archive::detail::polymorphic_iarchive_route<T> 0112 #endif 0113 0114 // endian and fpclassify 0115 #include <boost/math/special_functions/fpclassify.hpp> 0116 #include <boost/endian/conversion.hpp> 0117 0118 // namespace alias 0119 #if BOOST_VERSION < 103800 0120 namespace fp = boost::math; 0121 #elif BOOST_VERSION >= 106900 0122 namespace fp = boost::math; 0123 #else 0124 namespace fp = boost::spirit::math; 0125 #endif 0126 0127 #if BOOST_VERSION >= 104500 && !defined BOOST_NO_STD_WSTRING 0128 // used for wstring to utf8 conversion 0129 #include <boost/program_options/config.hpp> 0130 #include <boost/program_options/detail/convert.hpp> 0131 #endif 0132 0133 // generic type traits for numeric types 0134 #include <boost/type_traits/is_integral.hpp> 0135 #include <boost/type_traits/is_unsigned.hpp> 0136 #include <boost/type_traits/is_arithmetic.hpp> 0137 #include <boost/type_traits/is_floating_point.hpp> 0138 0139 #include "portable_archive_exception.hpp" 0140 0141 // hint from Johan Rade: on VMS there is still support for 0142 // the VAX floating point format and this macro detects it 0143 #if defined(__vms) && defined(__DECCXX) && !__IEEE_FLOAT 0144 #error "VAX floating point format is not supported!" 0145 #endif 0146 0147 namespace eos { 0148 0149 // forward declaration 0150 class portable_iarchive; 0151 0152 typedef boost::archive::basic_binary_iprimitive<portable_iarchive 0153 #if BOOST_VERSION < 103400 0154 , 0155 std::istream 0156 #else 0157 , 0158 std::istream::char_type, 0159 std::istream::traits_type 0160 #endif 0161 > 0162 portable_iprimitive; 0163 0164 /** 0165 * \brief Portable binary input archive using little endian format. 0166 * 0167 * This archive addresses integer size, endianness and floating point types so 0168 * that data can be transferred across different systems. There may still be 0169 * constraints as to what systems are compatible and the user will have to take 0170 * care that e.g. a very large int being saved on a 64 bit machine will result 0171 * in a portable_archive_exception if loaded into an int on a 32 bit system. 0172 * A possible workaround to this would be to use fixed types like 0173 * boost::uint64_t in your serialization structures. 0174 * 0175 * \note The class is based on the portable binary example by Robert Ramey and 0176 * uses Beman Dawes endian library plus fp_utilities by Johan Rade. 0177 */ 0178 class portable_iarchive : public portable_iprimitive 0179 0180 // the example derives from common_oarchive but that lacks the 0181 // load_override functions so we chose to stay one level higher 0182 , 0183 public boost::archive::basic_binary_iarchive<portable_iarchive> 0184 #if BOOST_VERSION >= 103500 && BOOST_VERSION < 105600 0185 // mix-in helper class for serializing shared_ptr 0186 , 0187 public boost::archive::detail::shared_ptr_helper 0188 #endif 0189 { 0190 // only needed for Robert's hack in basic_binary_iarchive::init 0191 friend class boost::archive::basic_binary_iarchive<portable_iarchive>; 0192 0193 // workaround for gcc: use a dummy struct 0194 // as additional argument type for overloading 0195 template <int> 0196 struct dummy { 0197 dummy(int) {} 0198 }; 0199 0200 // loads directly from stream 0201 inline signed char load_signed_char() { 0202 signed char c; 0203 portable_iprimitive::load(c); 0204 return c; 0205 } 0206 0207 // archive initialization 0208 void init(unsigned flags) { 0209 using namespace boost::archive; 0210 archive_version_type input_library_version(3); 0211 0212 // it is vital to have version information! 0213 // if we don't have any we assume boost 1.33 0214 if (flags & no_header) 0215 set_library_version(input_library_version); 0216 0217 // extract and check the magic eos byte 0218 else if (load_signed_char() != magic_byte) 0219 throw archive_exception(archive_exception::invalid_signature); 0220 0221 else { 0222 // extract version information 0223 operator>>(input_library_version); 0224 0225 // throw if file version is newer than we are 0226 if (input_library_version > archive_version) 0227 throw archive_exception(archive_exception::unsupported_version); 0228 0229 // else set the library version accordingly 0230 else 0231 set_library_version(input_library_version); 0232 } 0233 } 0234 0235 public: 0236 /** 0237 * \brief Constructor on a stream using ios::binary mode! 0238 * 0239 * We cannot call basic_binary_iprimitive::init which tries to detect 0240 * if the binary archive stems from a different platform by examining 0241 * type sizes. 0242 * 0243 * We could have called basic_binary_iarchive::init which would create 0244 * the boost::serialization standard archive header containing also the 0245 * library version. Due to efficiency we stick with our own. 0246 */ 0247 portable_iarchive(std::istream& is, unsigned flags = 0) 0248 #if BOOST_VERSION < 103400 0249 : portable_iprimitive(is, flags & boost::archive::no_codecvt) 0250 #else 0251 : portable_iprimitive(*is.rdbuf(), flags & boost::archive::no_codecvt) 0252 #endif 0253 , 0254 boost::archive::basic_binary_iarchive<portable_iarchive>(flags) { 0255 init(flags); 0256 } 0257 0258 #if BOOST_VERSION >= 103400 0259 portable_iarchive(std::streambuf& sb, unsigned flags = 0) 0260 : portable_iprimitive(sb, flags & boost::archive::no_codecvt), 0261 boost::archive::basic_binary_iarchive<portable_iarchive>(flags) { 0262 init(flags); 0263 } 0264 #endif 0265 0266 //! Load narrow strings. 0267 void load(std::string& s) { portable_iprimitive::load(s); } 0268 0269 #ifndef BOOST_NO_STD_WSTRING 0270 /** 0271 * \brief Load wide strings. 0272 * 0273 * This is rather tricky to get right for true portability as there 0274 * are so many different character encodings around. However, wide 0275 * strings that are encoded in one of the Unicode schemes only need 0276 * to be _transcoded_ which is a lot easier actually. 0277 * 0278 * We generate the output string to be encoded in the system's native 0279 * format, ie. UTF-16 on Windows and UTF-32 on Linux machines. Don't 0280 * know about Mac here so I can't really say about that. 0281 */ 0282 void load(std::wstring& s) { 0283 std::string utf8; 0284 load(utf8); 0285 s = boost::from_utf8(utf8); 0286 } 0287 #endif 0288 0289 /** 0290 * \brief Loading bool type. 0291 * 0292 * Byte pattern is same as with integer types, so this function 0293 * is somewhat redundant but treating bool as integer generates 0294 * a lot of compiler warnings. 0295 * 0296 * \note If you cannot compile your application and it says something 0297 * about load(bool) cannot convert your type A& into bool& then you 0298 * should check your BOOST_CLASS_IMPLEMENTATION setting for A, as 0299 * portable_archive is not able to handle custom primitive types in 0300 * a general manner. 0301 */ 0302 void load(bool& b) { 0303 switch (signed char c = load_signed_char()) { 0304 case 0: 0305 b = false; 0306 break; 0307 case 1: 0308 b = load_signed_char(); 0309 break; 0310 default: 0311 throw portable_archive_exception(c); 0312 } 0313 } 0314 0315 /** 0316 * \brief Load integer types. 0317 * 0318 * First we load the size information ie. the number of bytes that 0319 * hold the actual data. Then we retrieve the data and transform it 0320 * to the original value by using load_little_endian. 0321 */ 0322 template <typename T> 0323 typename boost::enable_if<boost::is_integral<T> >::type load(T& t, dummy<2> = 0) { 0324 // get the number of bytes in the stream 0325 if (signed char size = load_signed_char()) { 0326 // check for negative value in unsigned type 0327 if (size < 0 && boost::is_unsigned<T>::value) 0328 throw portable_archive_exception(); 0329 0330 // check that our type T is large enough 0331 else if ((unsigned)abs(size) > sizeof(T)) 0332 throw portable_archive_exception(size); 0333 0334 // reconstruct the value 0335 T temp = size < 0 ? -1 : 0; 0336 load_binary(&temp, abs(size)); 0337 0338 // load the value from little endian - it is then converted 0339 // to the target type T and fits it because size <= sizeof(T) 0340 t = boost::endian::little_to_native(temp); 0341 } 0342 0343 else 0344 t = 0; // zero optimization 0345 } 0346 0347 /** 0348 * \brief Load floating point types. 0349 * 0350 * We simply rely on fp_traits_non_native to set the bit pattern from the (unsigned) 0351 * integral type that was stored in the stream. Francois Mauger provided 0352 * standardized behaviour for special values like inf and NaN, that need to 0353 * be serialized in his application. 0354 * 0355 * \note by Johan Rade (author of the floating point utilities library): 0356 * Be warned that the math::detail::fp_traits_non_native<T,U>::get_bits() function 0357 * is *not* guaranteed to give you all bits of the floating point number. It 0358 * will give you all bits if and only if there is an integer type that has 0359 * the same size as the floating point you are copying from. It will not 0360 * give you all bits for double if there is no uint64_t. It will not give 0361 * you all bits for long double if sizeof(long double) > 8 or there is no 0362 * uint64_t. 0363 * 0364 * The member fp_traits<T>::type::coverage will tell you whether all bits 0365 * are copied. This is a typedef for either math::detail::all_bits or 0366 * math::detail::not_all_bits. 0367 * 0368 * If the function does not copy all bits, then it will copy the most 0369 * significant bits. So if you serialize and deserialize the way you 0370 * describe, and fp_traits<T>::type::coverage is math::detail::not_all_bits, 0371 * then your floating point numbers will be truncated. This will introduce 0372 * small rounding off errors. 0373 */ 0374 template <typename T> 0375 typename boost::enable_if<boost::is_floating_point<T> >::type load(T& t, dummy<3> = 0) { 0376 typedef typename fp::detail::size_to_precision<sizeof(T), ::std::is_floating_point<T>::value>::type precision; 0377 typedef typename fp::detail::fp_traits_non_native<T, precision> traits; 0378 0379 // if you end here there are three possibilities: 0380 // 1. you're serializing a long double which is not portable 0381 // 2. you're serializing a double but have no 64 bit integer 0382 // 3. your machine is using an unknown floating point format 0383 // after reading the note above you still might decide to 0384 // deactivate this static assert and try if it works out. 0385 typename traits::bits bits; 0386 static_assert(sizeof(bits) == sizeof(T)); 0387 static_assert(std::numeric_limits<T>::is_iec559); 0388 0389 load(bits); 0390 traits::set_bits(t, bits); 0391 0392 // if the no_infnan flag is set we must throw here 0393 if (get_flags() & no_infnan && !fp::isfinite(t)) 0394 throw portable_archive_exception(t); 0395 0396 // if you end here your floating point type does not support 0397 // denormalized numbers. this might be the case even though 0398 // your type conforms to IEC 559 (and thus to IEEE 754) 0399 if (std::numeric_limits<T>::has_denorm == std::denorm_absent && fp::fpclassify(t) == (int)FP_SUBNORMAL) // GCC4 0400 throw portable_archive_exception(t); 0401 } 0402 0403 // in boost 1.44 version_type was splitted into library_version_type and 0404 // item_version_type, plus a whole bunch of additional strong typedefs. 0405 template <typename T> 0406 typename boost::disable_if<boost::is_arithmetic<T> >::type load(T& t, dummy<4> = 0) { 0407 // we provide a generic load routine for all types that feature 0408 // conversion operators into an unsigned integer value like those 0409 // created through BOOST_STRONG_TYPEDEF(X, some unsigned int) like 0410 // library_version_type, collection_size_type, item_version_type, 0411 // class_id_type, object_id_type, version_type and tracking_type 0412 load((typename boost::uint_t<sizeof(T) * CHAR_BIT>::least&)(t)); 0413 } 0414 }; 0415 0416 // polymorphic portable binary iarchive typedef 0417 typedef POLYMORPHIC(portable_iarchive) polymorphic_portable_iarchive; 0418 #undef POLYMORPHIC 0419 0420 } // namespace eos 0421 0422 // this is required by export which registers all of your 0423 // classes with all the inbuilt archives plus our archive. 0424 #if BOOST_VERSION < 103500 0425 #define BOOST_ARCHIVE_CUSTOM_IARCHIVE_TYPES eos::portable_iarchive 0426 #else 0427 BOOST_SERIALIZATION_REGISTER_ARCHIVE(eos::portable_iarchive) 0428 BOOST_SERIALIZATION_REGISTER_ARCHIVE(eos::polymorphic_portable_iarchive) 0429 #endif 0430 0431 // if you include this header multiple times and your compiler is picky 0432 // about multiple template instantiations (eg. gcc is) then you need to 0433 // define NO_EXPLICIT_TEMPLATE_INSTANTIATION before every include but one 0434 // or you move the instantiation section into an implementation file 0435 // #ifndef NO_EXPLICIT_TEMPLATE_INSTANTIATION 0436 // 0437 // #include <boost/archive/impl/basic_binary_iarchive.ipp> 0438 // #include <boost/archive/impl/basic_binary_iprimitive.ipp> 0439 // 0440 // #if BOOST_VERSION < 104000 0441 // #include <boost/archive/impl/archive_pointer_iserializer.ipp> 0442 // #elif !defined BOOST_ARCHIVE_SERIALIZER_INCLUDED 0443 // #include <boost/archive/impl/archive_serializer_map.ipp> 0444 // #define BOOST_ARCHIVE_SERIALIZER_INCLUDED 0445 // #endif 0446 // 0447 // namespace boost { 0448 // namespace archive { 0449 // 0450 // // explicitly instantiate for this type of binary stream 0451 // template class basic_binary_iarchive<eos::portable_iarchive>; 0452 // 0453 // template class basic_binary_iprimitive<eos::portable_iarchive 0454 // #if BOOST_VERSION < 103400 0455 // , 0456 // std::istream 0457 // #else 0458 // , 0459 // std::istream::char_type, 0460 // std::istream::traits_type 0461 // #endif 0462 // >; 0463 // 0464 // #if BOOST_VERSION < 104000 0465 // template class detail::archive_pointer_iserializer<eos::portable_iarchive>; 0466 // #else 0467 // template class detail::archive_serializer_map<eos::portable_iarchive>; 0468 // //template class detail::archive_serializer_map<eos::polymorphic_portable_iarchive>; 0469 // #endif 0470 // 0471 // } // namespace archive 0472 // } // namespace boost 0473 // 0474 // #endif 0475 0476 #endif
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