src/thirdparty/boost_1_47_0/boost/smart_ptr/intrusive_ptr.hpp

   1 #ifndef BOOST_SMART_PTR_INTRUSIVE_PTR_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_INTRUSIVE_PTR_HPP_INCLUDED
   3
   4 //
   5 //  intrusive_ptr.hpp
   6 //
   7 //  Copyright (c) 2001, 2002 Peter Dimov
   8 //
   9 // Distributed under the Boost Software License, Version 1.0. (See
  10 // accompanying file LICENSE_1_0.txt or copy at
  11 // http://www.boost.org/LICENSE_1_0.txt)
  12 //
  13 //  See http://www.boost.org/libs/smart_ptr/intrusive_ptr.html for documentation.
  14 //
  15
  16 #include <boost/config.hpp>
  17
  18 #include <boost/assert.hpp>
  19 #include <boost/detail/workaround.hpp>
  20 #include <boost/smart_ptr/detail/sp_convertible.hpp>
  21
  22 #include <boost/config/no_tr1/functional.hpp>           // for std::less
  23
  24 #if !defined(BOOST_NO_IOSTREAM)
  25 #if !defined(BOOST_NO_IOSFWD)
  26 #include <iosfwd>               // for std::basic_ostream
  27 #else
  28 #include <ostream>
  29 #endif
  30 #endif
  31
  32
  33 namespace boost
  34 {
  35
  36 //
  37 //  intrusive_ptr
  38 //
  39 //  A smart pointer that uses intrusive reference counting.
  40 //
  41 //  Relies on unqualified calls to
  42 //
  43 //      void intrusive_ptr_add_ref(T * p);
  44 //      void intrusive_ptr_release(T * p);
  45 //
  46 //          (p != 0)
  47 //
  48 //  The object is responsible for destroying itself.
  49 //
  50
  51 template<class T> class intrusive_ptr
  52 {
  53 private:
  54
  55     typedef intrusive_ptr this_type;
  56
  57 public:
  58
  59     typedef T element_type;
  60
  61     intrusive_ptr(): px( 0 )
  62     {
  63     }
  64
  65     intrusive_ptr( T * p, bool add_ref = true ): px( p )
  66     {
  67         if( px != 0 && add_ref ) intrusive_ptr_add_ref( px );
  68     }
  69
  70 #if !defined(BOOST_NO_MEMBER_TEMPLATES) || defined(BOOST_MSVC6_MEMBER_TEMPLATES)
  71
  72     template<class U>
  73 #if !defined( BOOST_SP_NO_SP_CONVERTIBLE )
  74
  75     intrusive_ptr( intrusive_ptr<U> const & rhs, typename boost::detail::sp_enable_if_convertible<U,T>::type = boost::detail::sp_empty() )
  76
  77 #else
  78
  79     intrusive_ptr( intrusive_ptr<U> const & rhs )
  80
  81 #endif
  82     : px( rhs.get() )
  83     {
  84         if( px != 0 ) intrusive_ptr_add_ref( px );
  85     }
  86
  87 #endif
  88
  89     intrusive_ptr(intrusive_ptr const & rhs): px( rhs.px )
  90     {
  91         if( px != 0 ) intrusive_ptr_add_ref( px );
  92     }
  93
  94     ~intrusive_ptr()
  95     {
  96         if( px != 0 ) intrusive_ptr_release( px );
  97     }
  98
  99 #if !defined(BOOST_NO_MEMBER_TEMPLATES) || defined(BOOST_MSVC6_MEMBER_TEMPLATES)
 100
 101     template<class U> intrusive_ptr & operator=(intrusive_ptr<U> const & rhs)
 102     {
 103         this_type(rhs).swap(*this);
 104         return *this;
 105     }
 106
 107 #endif
 108
 109 // Move support
 110
 111 #if defined( BOOST_HAS_RVALUE_REFS )
 112
 113     intrusive_ptr(intrusive_ptr && rhs): px( rhs.px )
 114     {
 115         rhs.px = 0;
 116     }
 117
 118     intrusive_ptr & operator=(intrusive_ptr && rhs)
 119     {
 120         this_type( static_cast< intrusive_ptr && >( rhs ) ).swap(*this);
 121         return *this;
 122     }
 123
 124 #endif
 125
 126     intrusive_ptr & operator=(intrusive_ptr const & rhs)
 127     {
 128         this_type(rhs).swap(*this);
 129         return *this;
 130     }
 131
 132     intrusive_ptr & operator=(T * rhs)
 133     {
 134         this_type(rhs).swap(*this);
 135         return *this;
 136     }
 137
 138     void reset()
 139     {
 140         this_type().swap( *this );
 141     }
 142
 143     void reset( T * rhs )
 144     {
 145         this_type( rhs ).swap( *this );
 146     }
 147
 148     T * get() const
 149     {
 150         return px;
 151     }
 152
 153     T & operator*() const
 154     {
 155         BOOST_ASSERT( px != 0 );
 156         return *px;
 157     }
 158
 159     T * operator->() const
 160     {
 161         BOOST_ASSERT( px != 0 );
 162         return px;
 163     }
 164
 165 // implicit conversion to "bool"
 166 #include <boost/smart_ptr/detail/operator_bool.hpp>
 167
 168     void swap(intrusive_ptr & rhs)
 169     {
 170         T * tmp = px;
 171         px = rhs.px;
 172         rhs.px = tmp;
 173     }
 174
 175 private:
 176
 177     T * px;
 178 };
 179
 180 template<class T, class U> inline bool operator==(intrusive_ptr<T> const & a, intrusive_ptr<U> const & b)
 181 {
 182     return a.get() == b.get();
 183 }
 184
 185 template<class T, class U> inline bool operator!=(intrusive_ptr<T> const & a, intrusive_ptr<U> const & b)
 186 {
 187     return a.get() != b.get();
 188 }
 189
 190 template<class T, class U> inline bool operator==(intrusive_ptr<T> const & a, U * b)
 191 {
 192     return a.get() == b;
 193 }
 194
 195 template<class T, class U> inline bool operator!=(intrusive_ptr<T> const & a, U * b)
 196 {
 197     return a.get() != b;
 198 }
 199
 200 template<class T, class U> inline bool operator==(T * a, intrusive_ptr<U> const & b)
 201 {
 202     return a == b.get();
 203 }
 204
 205 template<class T, class U> inline bool operator!=(T * a, intrusive_ptr<U> const & b)
 206 {
 207     return a != b.get();
 208 }
 209
 210 #if __GNUC__ == 2 && __GNUC_MINOR__ <= 96
 211
 212 // Resolve the ambiguity between our op!= and the one in rel_ops
 213
 214 template<class T> inline bool operator!=(intrusive_ptr<T> const & a, intrusive_ptr<T> const & b)
 215 {
 216     return a.get() != b.get();
 217 }
 218
 219 #endif
 220
 221 template<class T> inline bool operator<(intrusive_ptr<T> const & a, intrusive_ptr<T> const & b)
 222 {
 223     return std::less<T *>()(a.get(), b.get());
 224 }
 225
 226 template<class T> void swap(intrusive_ptr<T> & lhs, intrusive_ptr<T> & rhs)
 227 {
 228     lhs.swap(rhs);
 229 }
 230
 231 // mem_fn support
 232
 233 template<class T> T * get_pointer(intrusive_ptr<T> const & p)
 234 {
 235     return p.get();
 236 }
 237
 238 template<class T, class U> intrusive_ptr<T> static_pointer_cast(intrusive_ptr<U> const & p)
 239 {
 240     return static_cast<T *>(p.get());
 241 }
 242
 243 template<class T, class U> intrusive_ptr<T> const_pointer_cast(intrusive_ptr<U> const & p)
 244 {
 245     return const_cast<T *>(p.get());
 246 }
 247
 248 template<class T, class U> intrusive_ptr<T> dynamic_pointer_cast(intrusive_ptr<U> const & p)
 249 {
 250     return dynamic_cast<T *>(p.get());
 251 }
 252
 253 // operator<<
 254
 255 #if !defined(BOOST_NO_IOSTREAM)
 256
 257 #if defined(BOOST_NO_TEMPLATED_IOSTREAMS) || ( defined(__GNUC__) &&  (__GNUC__ < 3) )
 258
 259 template<class Y> std::ostream & operator<< (std::ostream & os, intrusive_ptr<Y> const & p)
 260 {
 261     os << p.get();
 262     return os;
 263 }
 264
 265 #else
 266
 267 // in STLport's no-iostreams mode no iostream symbols can be used
 268 #ifndef _STLP_NO_IOSTREAMS
 269
 270 # if defined(BOOST_MSVC) && BOOST_WORKAROUND(BOOST_MSVC, < 1300 && __SGI_STL_PORT)
 271 // MSVC6 has problems finding std::basic_ostream through the using declaration in namespace _STL
 272 using std::basic_ostream;
 273 template<class E, class T, class Y> basic_ostream<E, T> & operator<< (basic_ostream<E, T> & os, intrusive_ptr<Y> const & p)
 274 # else
 275 template<class E, class T, class Y> std::basic_ostream<E, T> & operator<< (std::basic_ostream<E, T> & os, intrusive_ptr<Y> const & p)
 276 # endif
 277 {
 278     os << p.get();
 279     return os;
 280 }
 281
 282 #endif // _STLP_NO_IOSTREAMS
 283
 284 #endif // __GNUC__ < 3
 285
 286 #endif // !defined(BOOST_NO_IOSTREAM)
 287
 288 } // namespace boost
 289
 290 #endif  // #ifndef BOOST_SMART_PTR_INTRUSIVE_PTR_HPP_INCLUDED