/usr/include/boost/serialization/smart_cast.hpp is in libboost1.46-dev 1.46.1-7ubuntu3.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 | #ifndef BOOST_SERIALIZATION_SMART_CAST_HPP
#define BOOST_SERIALIZATION_SMART_CAST_HPP
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif
/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// smart_cast.hpp:
// (C) Copyright 2002 Robert Ramey - http://www.rrsd.com .
// Use, modification and distribution is subject to 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/serialization for updates, documentation, and revision history.
// casting of pointers and references.
// In casting between different C++ classes, there are a number of
// rules that have to be kept in mind in deciding whether to use
// static_cast or dynamic_cast.
// a) dynamic casting can only be applied when one of the types is polymorphic
// Otherwise static_cast must be used.
// b) only dynamic casting can do runtime error checking
// use of static_cast is generally un checked even when compiled for debug
// c) static_cast would be considered faster than dynamic_cast.
// If casting is applied to a template parameter, there is no apriori way
// to know which of the two casting methods will be permitted or convenient.
// smart_cast uses C++ type_traits, and program debug mode to select the
// most convenient cast to use.
#include <exception>
#include <typeinfo>
#include <cstddef> // NULL
#include <boost/config.hpp>
#include <boost/static_assert.hpp>
#include <boost/type_traits/is_base_and_derived.hpp>
#include <boost/type_traits/is_polymorphic.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/is_reference.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/type_traits/remove_pointer.hpp>
#include <boost/type_traits/remove_reference.hpp>
#include <boost/mpl/eval_if.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/or.hpp>
#include <boost/mpl/and.hpp>
#include <boost/mpl/not.hpp>
#include <boost/mpl/identity.hpp>
namespace boost {
namespace serialization {
namespace smart_cast_impl {
template<class T>
struct reference {
struct polymorphic {
struct linear {
template<class U>
static T cast(U & u){
return static_cast< T >(u);
}
};
struct cross {
template<class U>
static T cast(U & u){
return dynamic_cast< T >(u);
}
};
template<class U>
static T cast(U & u){
// if we're in debug mode
#if ! defined(NDEBUG) \
|| defined(__BORLANDC__) && (__BORLANDC__ <= 0x560) \
|| defined(__MWERKS__)
// do a checked dynamic cast
return cross::cast(u);
#else
// borland 5.51 chokes here so we can't use it
// note: if remove_reference isn't function for these types
// cross casting will be selected this will work but will
// not be the most efficient method. This will conflict with
// the original smart_cast motivation.
typedef BOOST_DEDUCED_TYPENAME mpl::eval_if<
BOOST_DEDUCED_TYPENAME mpl::and_<
mpl::not_<is_base_and_derived<
BOOST_DEDUCED_TYPENAME remove_reference< T >::type,
U
> >,
mpl::not_<is_base_and_derived<
U,
BOOST_DEDUCED_TYPENAME remove_reference< T >::type
> >
>,
// borland chokes w/o full qualification here
mpl::identity<cross>,
mpl::identity<linear>
>::type typex;
// typex works around gcc 2.95 issue
return typex::cast(u);
#endif
}
};
struct non_polymorphic {
template<class U>
static T cast(U & u){
return static_cast< T >(u);
}
};
template<class U>
static T cast(U & u){
#if defined(__BORLANDC__)
return mpl::eval_if<
boost::is_polymorphic<U>,
mpl::identity<polymorphic>,
mpl::identity<non_polymorphic>
>::type::cast(u);
#else
typedef BOOST_DEDUCED_TYPENAME mpl::eval_if<
boost::is_polymorphic<U>,
mpl::identity<polymorphic>,
mpl::identity<non_polymorphic>
>::type typex;
return typex::cast(u);
#endif
}
};
template<class T>
struct pointer {
struct polymorphic {
// unfortunately, this below fails to work for virtual base
// classes. need has_virtual_base to do this.
// Subject for further study
#if 0
struct linear {
template<class U>
static T cast(U * u){
return static_cast< T >(u);
}
};
struct cross {
template<class U>
static T cast(U * u){
T tmp = dynamic_cast< T >(u);
#ifndef NDEBUG
if ( tmp == 0 ) throw std::bad_cast();
#endif
return tmp;
}
};
template<class U>
static T cast(U * u){
// if we're in debug mode
#if ! defined(NDEBUG) || defined(__BORLANDC__) && (__BORLANDC__ <= 0x560)
// do a checked dynamic cast
return cross::cast(u);
#else
// borland 5.51 chokes here so we can't use it
// note: if remove_pointer isn't function for these types
// cross casting will be selected this will work but will
// not be the most efficient method. This will conflict with
// the original smart_cast motivation.
typedef
BOOST_DEDUCED_TYPENAME mpl::eval_if<
BOOST_DEDUCED_TYPENAME mpl::and_<
mpl::not_<is_base_and_derived<
BOOST_DEDUCED_TYPENAME remove_pointer< T >::type,
U
> >,
mpl::not_<is_base_and_derived<
U,
BOOST_DEDUCED_TYPENAME remove_pointer< T >::type
> >
>,
// borland chokes w/o full qualification here
mpl::identity<cross>,
mpl::identity<linear>
>::type typex;
return typex::cast(u);
#endif
}
#else
template<class U>
static T cast(U * u){
T tmp = dynamic_cast< T >(u);
#ifndef NDEBUG
if ( tmp == 0 ) throw std::bad_cast();
#endif
return tmp;
}
#endif
};
struct non_polymorphic {
template<class U>
static T cast(U * u){
return static_cast< T >(u);
}
};
template<class U>
static T cast(U * u){
#if defined(__BORLANDC__)
return mpl::eval_if<
boost::is_polymorphic<U>,
mpl::identity<polymorphic>,
mpl::identity<non_polymorphic>
>::type::cast(u);
#else
typedef BOOST_DEDUCED_TYPENAME mpl::eval_if<
boost::is_polymorphic<U>,
mpl::identity<polymorphic>,
mpl::identity<non_polymorphic>
>::type typex;
return typex::cast(u);
#endif
}
};
template<class TPtr>
struct void_pointer {
template<class UPtr>
static TPtr cast(UPtr uptr){
return static_cast<TPtr>(uptr);
}
};
template<class T>
struct error {
// if we get here, its because we are using one argument in the
// cast on a system which doesn't support partial template
// specialization
template<class U>
static T cast(U u){
BOOST_STATIC_ASSERT(sizeof(T)==0);
return * static_cast<T *>(NULL);
}
};
} // smart_cast_impl
// this implements:
// smart_cast<Target *, Source *>(Source * s)
// smart_cast<Target &, Source &>(s)
// note that it will fail with
// smart_cast<Target &>(s)
template<class T, class U>
T smart_cast(U u) {
typedef
BOOST_DEDUCED_TYPENAME mpl::eval_if<
BOOST_DEDUCED_TYPENAME mpl::or_<
boost::is_same<void *, U>,
boost::is_same<void *, T>,
boost::is_same<const void *, U>,
boost::is_same<const void *, T>
>,
mpl::identity<smart_cast_impl::void_pointer< T > >,
// else
BOOST_DEDUCED_TYPENAME mpl::eval_if<boost::is_pointer<U>,
mpl::identity<smart_cast_impl::pointer< T > >,
// else
BOOST_DEDUCED_TYPENAME mpl::eval_if<boost::is_reference<U>,
mpl::identity<smart_cast_impl::reference< T > >,
// else
mpl::identity<smart_cast_impl::error< T >
>
>
>
>::type typex;
return typex::cast(u);
}
// this implements:
// smart_cast_reference<Target &>(Source & s)
template<class T, class U>
T smart_cast_reference(U & u) {
return smart_cast_impl::reference< T >::cast(u);
}
} // namespace serialization
} // namespace boost
#endif // BOOST_SERIALIZATION_SMART_CAST_HPP
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