ceph/src/boost/libs/smart_ptr/include/boost/smart_ptr/shared_ptr.hpp

   1 #ifndef BOOST_SMART_PTR_SHARED_PTR_HPP_INCLUDED
   2 #define BOOST_SMART_PTR_SHARED_PTR_HPP_INCLUDED
   3
   4 //
   5 //  shared_ptr.hpp
   6 //
   7 //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
   8 //  Copyright (c) 2001-2008 Peter Dimov
   9 //
  10 //  Distributed under the Boost Software License, Version 1.0. (See
  11 //  accompanying file LICENSE_1_0.txt or copy at
  12 //  http://www.boost.org/LICENSE_1_0.txt)
  13 //
  14 //  See http://www.boost.org/libs/smart_ptr/shared_ptr.htm for documentation.
  15 //
  16
  17 #include <boost/config.hpp>   // for broken compiler workarounds
  18
  19 // In order to avoid circular dependencies with Boost.TR1
  20 // we make sure that our include of <memory> doesn't try to
  21 // pull in the TR1 headers: that's why we use this header
  22 // rather than including <memory> directly:
  23 #include <boost/config/no_tr1/memory.hpp>  // std::auto_ptr
  24
  25 #include <boost/assert.hpp>
  26 #include <boost/checked_delete.hpp>
  27 #include <boost/throw_exception.hpp>
  28 #include <boost/smart_ptr/detail/shared_count.hpp>
  29 #include <boost/detail/workaround.hpp>
  30 #include <boost/smart_ptr/detail/sp_convertible.hpp>
  31 #include <boost/smart_ptr/detail/sp_nullptr_t.hpp>
  32 #include <boost/smart_ptr/detail/sp_disable_deprecated.hpp>
  33
  34 #if !defined(BOOST_SP_NO_ATOMIC_ACCESS)
  35 #include <boost/smart_ptr/detail/spinlock_pool.hpp>
  36 #endif
  37
  38 #include <algorithm>            // for std::swap
  39 #include <functional>           // for std::less
  40 #include <typeinfo>             // for std::bad_cast
  41 #include <cstddef>              // for std::size_t
  42
  43 #if !defined(BOOST_NO_IOSTREAM)
  44 #if !defined(BOOST_NO_IOSFWD)
  45 #include <iosfwd>               // for std::basic_ostream
  46 #else
  47 #include <ostream>
  48 #endif
  49 #endif
  50
  51 #if defined( BOOST_SP_DISABLE_DEPRECATED )
  52 #pragma GCC diagnostic push
  53 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
  54 #endif
  55
  56 namespace boost
  57 {
  58
  59 template<class T> class shared_ptr;
  60 template<class T> class weak_ptr;
  61 template<class T> class enable_shared_from_this;
  62 class enable_shared_from_raw;
  63
  64 namespace movelib
  65 {
  66
  67     template< class T, class D > class unique_ptr;
  68
  69 } // namespace movelib
  70
  71 namespace detail
  72 {
  73
  74 // sp_element, element_type
  75
  76 template< class T > struct sp_element
  77 {
  78     typedef T type;
  79 };
  80
  81 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
  82
  83 template< class T > struct sp_element< T[] >
  84 {
  85     typedef T type;
  86 };
  87
  88 #if !defined( __BORLANDC__ ) || !BOOST_WORKAROUND( __BORLANDC__, < 0x600 )
  89
  90 template< class T, std::size_t N > struct sp_element< T[N] >
  91 {
  92     typedef T type;
  93 };
  94
  95 #endif
  96
  97 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
  98
  99 // sp_dereference, return type of operator*
 100
 101 template< class T > struct sp_dereference
 102 {
 103     typedef T & type;
 104 };
 105
 106 template<> struct sp_dereference< void >
 107 {
 108     typedef void type;
 109 };
 110
 111 #if !defined(BOOST_NO_CV_VOID_SPECIALIZATIONS)
 112
 113 template<> struct sp_dereference< void const >
 114 {
 115     typedef void type;
 116 };
 117
 118 template<> struct sp_dereference< void volatile >
 119 {
 120     typedef void type;
 121 };
 122
 123 template<> struct sp_dereference< void const volatile >
 124 {
 125     typedef void type;
 126 };
 127
 128 #endif // !defined(BOOST_NO_CV_VOID_SPECIALIZATIONS)
 129
 130 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 131
 132 template< class T > struct sp_dereference< T[] >
 133 {
 134     typedef void type;
 135 };
 136
 137 #if !defined( __BORLANDC__ ) || !BOOST_WORKAROUND( __BORLANDC__, < 0x600 )
 138
 139 template< class T, std::size_t N > struct sp_dereference< T[N] >
 140 {
 141     typedef void type;
 142 };
 143
 144 #endif
 145
 146 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 147
 148 // sp_member_access, return type of operator->
 149
 150 template< class T > struct sp_member_access
 151 {
 152     typedef T * type;
 153 };
 154
 155 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 156
 157 template< class T > struct sp_member_access< T[] >
 158 {
 159     typedef void type;
 160 };
 161
 162 #if !defined( __BORLANDC__ ) || !BOOST_WORKAROUND( __BORLANDC__, < 0x600 )
 163
 164 template< class T, std::size_t N > struct sp_member_access< T[N] >
 165 {
 166     typedef void type;
 167 };
 168
 169 #endif
 170
 171 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 172
 173 // sp_array_access, return type of operator[]
 174
 175 template< class T > struct sp_array_access
 176 {
 177     typedef void type;
 178 };
 179
 180 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 181
 182 template< class T > struct sp_array_access< T[] >
 183 {
 184     typedef T & type;
 185 };
 186
 187 #if !defined( __BORLANDC__ ) || !BOOST_WORKAROUND( __BORLANDC__, < 0x600 )
 188
 189 template< class T, std::size_t N > struct sp_array_access< T[N] >
 190 {
 191     typedef T & type;
 192 };
 193
 194 #endif
 195
 196 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 197
 198 // sp_extent, for operator[] index check
 199
 200 template< class T > struct sp_extent
 201 {
 202     enum _vt { value = 0 };
 203 };
 204
 205 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 206
 207 template< class T, std::size_t N > struct sp_extent< T[N] >
 208 {
 209     enum _vt { value = N };
 210 };
 211
 212 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 213
 214 // enable_shared_from_this support
 215
 216 template< class X, class Y, class T > inline void sp_enable_shared_from_this( boost::shared_ptr<X> const * ppx, Y const * py, boost::enable_shared_from_this< T > const * pe )
 217 {
 218     if( pe != 0 )
 219     {
 220         pe->_internal_accept_owner( ppx, const_cast< Y* >( py ) );
 221     }
 222 }
 223
 224 template< class X, class Y > inline void sp_enable_shared_from_this( boost::shared_ptr<X> * ppx, Y const * py, boost::enable_shared_from_raw const * pe );
 225
 226 #ifdef _MANAGED
 227
 228 // Avoid C4793, ... causes native code generation
 229
 230 struct sp_any_pointer
 231 {
 232     template<class T> sp_any_pointer( T* ) {}
 233 };
 234
 235 inline void sp_enable_shared_from_this( sp_any_pointer, sp_any_pointer, sp_any_pointer )
 236 {
 237 }
 238
 239 #else // _MANAGED
 240
 241 inline void sp_enable_shared_from_this( ... )
 242 {
 243 }
 244
 245 #endif // _MANAGED
 246
 247 #if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )
 248
 249 // rvalue auto_ptr support based on a technique by Dave Abrahams
 250
 251 template< class T, class R > struct sp_enable_if_auto_ptr
 252 {
 253 };
 254
 255 template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >
 256 {
 257     typedef R type;
 258 };
 259
 260 #endif
 261
 262 // sp_assert_convertible
 263
 264 template< class Y, class T > inline void sp_assert_convertible()
 265 {
 266 #if !defined( BOOST_SP_NO_SP_CONVERTIBLE )
 267
 268     // static_assert( sp_convertible< Y, T >::value );
 269     typedef char tmp[ sp_convertible< Y, T >::value? 1: -1 ];
 270     (void)sizeof( tmp );
 271
 272 #else
 273
 274     T* p = static_cast< Y* >( 0 );
 275     (void)p;
 276
 277 #endif
 278 }
 279
 280 // pointer constructor helper
 281
 282 template< class T, class Y > inline void sp_pointer_construct( boost::shared_ptr< T > * ppx, Y * p, boost::detail::shared_count & pn )
 283 {
 284     boost::detail::shared_count( p ).swap( pn );
 285     boost::detail::sp_enable_shared_from_this( ppx, p, p );
 286 }
 287
 288 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 289
 290 template< class T, class Y > inline void sp_pointer_construct( boost::shared_ptr< T[] > * /*ppx*/, Y * p, boost::detail::shared_count & pn )
 291 {
 292     sp_assert_convertible< Y[], T[] >();
 293     boost::detail::shared_count( p, boost::checked_array_deleter< T >() ).swap( pn );
 294 }
 295
 296 template< class T, std::size_t N, class Y > inline void sp_pointer_construct( boost::shared_ptr< T[N] > * /*ppx*/, Y * p, boost::detail::shared_count & pn )
 297 {
 298     sp_assert_convertible< Y[N], T[N] >();
 299     boost::detail::shared_count( p, boost::checked_array_deleter< T >() ).swap( pn );
 300 }
 301
 302 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 303
 304 // deleter constructor helper
 305
 306 template< class T, class Y > inline void sp_deleter_construct( boost::shared_ptr< T > * ppx, Y * p )
 307 {
 308     boost::detail::sp_enable_shared_from_this( ppx, p, p );
 309 }
 310
 311 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 312
 313 template< class T, class Y > inline void sp_deleter_construct( boost::shared_ptr< T[] > * /*ppx*/, Y * /*p*/ )
 314 {
 315     sp_assert_convertible< Y[], T[] >();
 316 }
 317
 318 template< class T, std::size_t N, class Y > inline void sp_deleter_construct( boost::shared_ptr< T[N] > * /*ppx*/, Y * /*p*/ )
 319 {
 320     sp_assert_convertible< Y[N], T[N] >();
 321 }
 322
 323 #endif // !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 324
 325 } // namespace detail
 326
 327
 328 //
 329 //  shared_ptr
 330 //
 331 //  An enhanced relative of scoped_ptr with reference counted copy semantics.
 332 //  The object pointed to is deleted when the last shared_ptr pointing to it
 333 //  is destroyed or reset.
 334 //
 335
 336 template<class T> class shared_ptr
 337 {
 338 private:
 339
 340     // Borland 5.5.1 specific workaround
 341     typedef shared_ptr<T> this_type;
 342
 343 public:
 344
 345     typedef typename boost::detail::sp_element< T >::type element_type;
 346
 347     shared_ptr() BOOST_NOEXCEPT : px( 0 ), pn() // never throws in 1.30+
 348     {
 349     }
 350
 351 #if !defined( BOOST_NO_CXX11_NULLPTR )
 352
 353     shared_ptr( boost::detail::sp_nullptr_t ) BOOST_NOEXCEPT : px( 0 ), pn() // never throws
 354     {
 355     }
 356
 357 #endif
 358
 359     template<class Y>
 360     explicit shared_ptr( Y * p ): px( p ), pn() // Y must be complete
 361     {
 362         boost::detail::sp_pointer_construct( this, p, pn );
 363     }
 364
 365     //
 366     // Requirements: D's copy constructor must not throw
 367     //
 368     // shared_ptr will release p by calling d(p)
 369     //
 370
 371     template<class Y, class D> shared_ptr( Y * p, D d ): px( p ), pn( p, d )
 372     {
 373         boost::detail::sp_deleter_construct( this, p );
 374     }
 375
 376 #if !defined( BOOST_NO_CXX11_NULLPTR )
 377
 378     template<class D> shared_ptr( boost::detail::sp_nullptr_t p, D d ): px( p ), pn( p, d )
 379     {
 380     }
 381
 382 #endif
 383
 384     // As above, but with allocator. A's copy constructor shall not throw.
 385
 386     template<class Y, class D, class A> shared_ptr( Y * p, D d, A a ): px( p ), pn( p, d, a )
 387     {
 388         boost::detail::sp_deleter_construct( this, p );
 389     }
 390
 391 #if !defined( BOOST_NO_CXX11_NULLPTR )
 392
 393     template<class D, class A> shared_ptr( boost::detail::sp_nullptr_t p, D d, A a ): px( p ), pn( p, d, a )
 394     {
 395     }
 396
 397 #endif
 398
 399 //  generated copy constructor, destructor are fine...
 400
 401 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 402
 403 // ... except in C++0x, move disables the implicit copy
 404
 405     shared_ptr( shared_ptr const & r ) BOOST_NOEXCEPT : px( r.px ), pn( r.pn )
 406     {
 407     }
 408
 409 #endif
 410
 411     template<class Y>
 412     explicit shared_ptr( weak_ptr<Y> const & r ): pn( r.pn ) // may throw
 413     {
 414         boost::detail::sp_assert_convertible< Y, T >();
 415
 416         // it is now safe to copy r.px, as pn(r.pn) did not throw
 417         px = r.px;
 418     }
 419
 420     template<class Y>
 421     shared_ptr( weak_ptr<Y> const & r, boost::detail::sp_nothrow_tag )
 422     BOOST_NOEXCEPT : px( 0 ), pn( r.pn, boost::detail::sp_nothrow_tag() )
 423     {
 424         if( !pn.empty() )
 425         {
 426             px = r.px;
 427         }
 428     }
 429
 430     template<class Y>
 431 #if !defined( BOOST_SP_NO_SP_CONVERTIBLE )
 432
 433     shared_ptr( shared_ptr<Y> const & r, typename boost::detail::sp_enable_if_convertible<Y,T>::type = boost::detail::sp_empty() )
 434
 435 #else
 436
 437     shared_ptr( shared_ptr<Y> const & r )
 438
 439 #endif
 440     BOOST_NOEXCEPT : px( r.px ), pn( r.pn )
 441     {
 442         boost::detail::sp_assert_convertible< Y, T >();
 443     }
 444
 445     // aliasing
 446     template< class Y >
 447     shared_ptr( shared_ptr<Y> const & r, element_type * p ) BOOST_NOEXCEPT : px( p ), pn( r.pn )
 448     {
 449     }
 450
 451 #ifndef BOOST_NO_AUTO_PTR
 452
 453     template<class Y>
 454     explicit shared_ptr( std::auto_ptr<Y> & r ): px(r.get()), pn()
 455     {
 456         boost::detail::sp_assert_convertible< Y, T >();
 457
 458         Y * tmp = r.get();
 459         pn = boost::detail::shared_count( r );
 460
 461         boost::detail::sp_deleter_construct( this, tmp );
 462     }
 463
 464 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 465
 466     template<class Y>
 467     shared_ptr( std::auto_ptr<Y> && r ): px(r.get()), pn()
 468     {
 469         boost::detail::sp_assert_convertible< Y, T >();
 470
 471         Y * tmp = r.get();
 472         pn = boost::detail::shared_count( r );
 473
 474         boost::detail::sp_deleter_construct( this, tmp );
 475     }
 476
 477 #elif !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 478
 479     template<class Ap>
 480     explicit shared_ptr( Ap r, typename boost::detail::sp_enable_if_auto_ptr<Ap, int>::type = 0 ): px( r.get() ), pn()
 481     {
 482         typedef typename Ap::element_type Y;
 483
 484         boost::detail::sp_assert_convertible< Y, T >();
 485
 486         Y * tmp = r.get();
 487         pn = boost::detail::shared_count( r );
 488
 489         boost::detail::sp_deleter_construct( this, tmp );
 490     }
 491
 492 #endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
 493
 494 #endif // BOOST_NO_AUTO_PTR
 495
 496 #if !defined( BOOST_NO_CXX11_SMART_PTR ) && !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 497
 498     template< class Y, class D >
 499     shared_ptr( std::unique_ptr< Y, D > && r ): px( r.get() ), pn()
 500     {
 501         boost::detail::sp_assert_convertible< Y, T >();
 502
 503         typename std::unique_ptr< Y, D >::pointer tmp = r.get();
 504         pn = boost::detail::shared_count( r );
 505
 506         boost::detail::sp_deleter_construct( this, tmp );
 507     }
 508
 509 #endif
 510
 511     template< class Y, class D >
 512     shared_ptr( boost::movelib::unique_ptr< Y, D > r ): px( r.get() ), pn()
 513     {
 514         boost::detail::sp_assert_convertible< Y, T >();
 515
 516         typename boost::movelib::unique_ptr< Y, D >::pointer tmp = r.get();
 517         pn = boost::detail::shared_count( r );
 518
 519         boost::detail::sp_deleter_construct( this, tmp );
 520     }
 521
 522     // assignment
 523
 524     shared_ptr & operator=( shared_ptr const & r ) BOOST_NOEXCEPT
 525     {
 526         this_type(r).swap(*this);
 527         return *this;
 528     }
 529
 530 #if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1400)
 531
 532     template<class Y>
 533     shared_ptr & operator=(shared_ptr<Y> const & r) BOOST_NOEXCEPT
 534     {
 535         this_type(r).swap(*this);
 536         return *this;
 537     }
 538
 539 #endif
 540
 541 #ifndef BOOST_NO_AUTO_PTR
 542
 543     template<class Y>
 544     shared_ptr & operator=( std::auto_ptr<Y> & r )
 545     {
 546         this_type( r ).swap( *this );
 547         return *this;
 548     }
 549
 550 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 551
 552     template<class Y>
 553     shared_ptr & operator=( std::auto_ptr<Y> && r )
 554     {
 555         this_type( static_cast< std::auto_ptr<Y> && >( r ) ).swap( *this );
 556         return *this;
 557     }
 558
 559 #elif !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
 560
 561     template<class Ap>
 562     typename boost::detail::sp_enable_if_auto_ptr< Ap, shared_ptr & >::type operator=( Ap r )
 563     {
 564         this_type( r ).swap( *this );
 565         return *this;
 566     }
 567
 568 #endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
 569
 570 #endif // BOOST_NO_AUTO_PTR
 571
 572 #if !defined( BOOST_NO_CXX11_SMART_PTR ) && !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 573
 574     template<class Y, class D>
 575     shared_ptr & operator=( std::unique_ptr<Y, D> && r )
 576     {
 577         this_type( static_cast< std::unique_ptr<Y, D> && >( r ) ).swap(*this);
 578         return *this;
 579     }
 580
 581 #endif
 582
 583     template<class Y, class D>
 584     shared_ptr & operator=( boost::movelib::unique_ptr<Y, D> r )
 585     {
 586         // this_type( static_cast< unique_ptr<Y, D> && >( r ) ).swap( *this );
 587
 588         boost::detail::sp_assert_convertible< Y, T >();
 589
 590         typename boost::movelib::unique_ptr< Y, D >::pointer p = r.get();
 591
 592         shared_ptr tmp;
 593
 594         tmp.px = p;
 595         tmp.pn = boost::detail::shared_count( r );
 596
 597         boost::detail::sp_deleter_construct( &tmp, p );
 598
 599         tmp.swap( *this );
 600
 601         return *this;
 602     }
 603
 604 // Move support
 605
 606 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 607
 608     shared_ptr( shared_ptr && r ) BOOST_NOEXCEPT : px( r.px ), pn()
 609     {
 610         pn.swap( r.pn );
 611         r.px = 0;
 612     }
 613
 614     template<class Y>
 615 #if !defined( BOOST_SP_NO_SP_CONVERTIBLE )
 616
 617     shared_ptr( shared_ptr<Y> && r, typename boost::detail::sp_enable_if_convertible<Y,T>::type = boost::detail::sp_empty() )
 618
 619 #else
 620
 621     shared_ptr( shared_ptr<Y> && r )
 622
 623 #endif
 624     BOOST_NOEXCEPT : px( r.px ), pn()
 625     {
 626         boost::detail::sp_assert_convertible< Y, T >();
 627
 628         pn.swap( r.pn );
 629         r.px = 0;
 630     }
 631
 632     shared_ptr & operator=( shared_ptr && r ) BOOST_NOEXCEPT
 633     {
 634         this_type( static_cast< shared_ptr && >( r ) ).swap( *this );
 635         return *this;
 636     }
 637
 638     template<class Y>
 639     shared_ptr & operator=( shared_ptr<Y> && r ) BOOST_NOEXCEPT
 640     {
 641         this_type( static_cast< shared_ptr<Y> && >( r ) ).swap( *this );
 642         return *this;
 643     }
 644
 645     // aliasing move
 646     template<class Y>
 647     shared_ptr( shared_ptr<Y> && r, element_type * p ) BOOST_NOEXCEPT : px( p ), pn()
 648     {
 649         pn.swap( r.pn );
 650         r.px = 0;
 651     }
 652
 653 #endif
 654
 655 #if !defined( BOOST_NO_CXX11_NULLPTR )
 656
 657     shared_ptr & operator=( boost::detail::sp_nullptr_t ) BOOST_NOEXCEPT // never throws
 658     {
 659         this_type().swap(*this);
 660         return *this;
 661     }
 662
 663 #endif
 664
 665     void reset() BOOST_NOEXCEPT // never throws in 1.30+
 666     {
 667         this_type().swap(*this);
 668     }
 669
 670     template<class Y> void reset( Y * p ) // Y must be complete
 671     {
 672         BOOST_ASSERT( p == 0 || p != px ); // catch self-reset errors
 673         this_type( p ).swap( *this );
 674     }
 675
 676     template<class Y, class D> void reset( Y * p, D d )
 677     {
 678         this_type( p, d ).swap( *this );
 679     }
 680
 681     template<class Y, class D, class A> void reset( Y * p, D d, A a )
 682     {
 683         this_type( p, d, a ).swap( *this );
 684     }
 685
 686     template<class Y> void reset( shared_ptr<Y> const & r, element_type * p )
 687     {
 688         this_type( r, p ).swap( *this );
 689     }
 690
 691 #if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES )
 692
 693     template<class Y> void reset( shared_ptr<Y> && r, element_type * p )
 694     {
 695         this_type( static_cast< shared_ptr<Y> && >( r ), p ).swap( *this );
 696     }
 697
 698 #endif
 699
 700     // never throws (but has a BOOST_ASSERT in it, so not marked with BOOST_NOEXCEPT)
 701     typename boost::detail::sp_dereference< T >::type operator* () const
 702     {
 703         BOOST_ASSERT( px != 0 );
 704         return *px;
 705     }
 706
 707     // never throws (but has a BOOST_ASSERT in it, so not marked with BOOST_NOEXCEPT)
 708     typename boost::detail::sp_member_access< T >::type operator-> () const
 709     {
 710         BOOST_ASSERT( px != 0 );
 711         return px;
 712     }
 713
 714     // never throws (but has a BOOST_ASSERT in it, so not marked with BOOST_NOEXCEPT)
 715     typename boost::detail::sp_array_access< T >::type operator[] ( std::ptrdiff_t i ) const
 716     {
 717         BOOST_ASSERT( px != 0 );
 718         BOOST_ASSERT( i >= 0 && ( i < boost::detail::sp_extent< T >::value || boost::detail::sp_extent< T >::value == 0 ) );
 719
 720         return static_cast< typename boost::detail::sp_array_access< T >::type >( px[ i ] );
 721     }
 722
 723     element_type * get() const BOOST_NOEXCEPT
 724     {
 725         return px;
 726     }
 727
 728 // implicit conversion to "bool"
 729 #include <boost/smart_ptr/detail/operator_bool.hpp>
 730
 731     bool unique() const BOOST_NOEXCEPT
 732     {
 733         return pn.unique();
 734     }
 735
 736     long use_count() const BOOST_NOEXCEPT
 737     {
 738         return pn.use_count();
 739     }
 740
 741     void swap( shared_ptr & other ) BOOST_NOEXCEPT
 742     {
 743         std::swap(px, other.px);
 744         pn.swap(other.pn);
 745     }
 746
 747     template<class Y> bool owner_before( shared_ptr<Y> const & rhs ) const BOOST_NOEXCEPT
 748     {
 749         return pn < rhs.pn;
 750     }
 751
 752     template<class Y> bool owner_before( weak_ptr<Y> const & rhs ) const BOOST_NOEXCEPT
 753     {
 754         return pn < rhs.pn;
 755     }
 756
 757     void * _internal_get_deleter( boost::detail::sp_typeinfo const & ti ) const BOOST_NOEXCEPT
 758     {
 759         return pn.get_deleter( ti );
 760     }
 761
 762     void * _internal_get_untyped_deleter() const BOOST_NOEXCEPT
 763     {
 764         return pn.get_untyped_deleter();
 765     }
 766
 767     bool _internal_equiv( shared_ptr const & r ) const BOOST_NOEXCEPT
 768     {
 769         return px == r.px && pn == r.pn;
 770     }
 771
 772 // Tasteless as this may seem, making all members public allows member templates
 773 // to work in the absence of member template friends. (Matthew Langston)
 774
 775 #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
 776
 777 private:
 778
 779     template<class Y> friend class shared_ptr;
 780     template<class Y> friend class weak_ptr;
 781
 782
 783 #endif
 784
 785     element_type * px;                 // contained pointer
 786     boost::detail::shared_count pn;    // reference counter
 787
 788 };  // shared_ptr
 789
 790 template<class T, class U> inline bool operator==(shared_ptr<T> const & a, shared_ptr<U> const & b) BOOST_NOEXCEPT
 791 {
 792     return a.get() == b.get();
 793 }
 794
 795 template<class T, class U> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<U> const & b) BOOST_NOEXCEPT
 796 {
 797     return a.get() != b.get();
 798 }
 799
 800 #if __GNUC__ == 2 && __GNUC_MINOR__ <= 96
 801
 802 // Resolve the ambiguity between our op!= and the one in rel_ops
 803
 804 template<class T> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<T> const & b) BOOST_NOEXCEPT
 805 {
 806     return a.get() != b.get();
 807 }
 808
 809 #endif
 810
 811 #if !defined( BOOST_NO_CXX11_NULLPTR )
 812
 813 template<class T> inline bool operator==( shared_ptr<T> const & p, boost::detail::sp_nullptr_t ) BOOST_NOEXCEPT
 814 {
 815     return p.get() == 0;
 816 }
 817
 818 template<class T> inline bool operator==( boost::detail::sp_nullptr_t, shared_ptr<T> const & p ) BOOST_NOEXCEPT
 819 {
 820     return p.get() == 0;
 821 }
 822
 823 template<class T> inline bool operator!=( shared_ptr<T> const & p, boost::detail::sp_nullptr_t ) BOOST_NOEXCEPT
 824 {
 825     return p.get() != 0;
 826 }
 827
 828 template<class T> inline bool operator!=( boost::detail::sp_nullptr_t, shared_ptr<T> const & p ) BOOST_NOEXCEPT
 829 {
 830     return p.get() != 0;
 831 }
 832
 833 #endif
 834
 835 template<class T, class U> inline bool operator<(shared_ptr<T> const & a, shared_ptr<U> const & b) BOOST_NOEXCEPT
 836 {
 837     return a.owner_before( b );
 838 }
 839
 840 template<class T> inline void swap(shared_ptr<T> & a, shared_ptr<T> & b) BOOST_NOEXCEPT
 841 {
 842     a.swap(b);
 843 }
 844
 845 template<class T, class U> shared_ptr<T> static_pointer_cast( shared_ptr<U> const & r ) BOOST_NOEXCEPT
 846 {
 847     (void) static_cast< T* >( static_cast< U* >( 0 ) );
 848
 849     typedef typename shared_ptr<T>::element_type E;
 850
 851     E * p = static_cast< E* >( r.get() );
 852     return shared_ptr<T>( r, p );
 853 }
 854
 855 template<class T, class U> shared_ptr<T> const_pointer_cast( shared_ptr<U> const & r ) BOOST_NOEXCEPT
 856 {
 857     (void) const_cast< T* >( static_cast< U* >( 0 ) );
 858
 859     typedef typename shared_ptr<T>::element_type E;
 860
 861     E * p = const_cast< E* >( r.get() );
 862     return shared_ptr<T>( r, p );
 863 }
 864
 865 template<class T, class U> shared_ptr<T> dynamic_pointer_cast( shared_ptr<U> const & r ) BOOST_NOEXCEPT
 866 {
 867     (void) dynamic_cast< T* >( static_cast< U* >( 0 ) );
 868
 869     typedef typename shared_ptr<T>::element_type E;
 870
 871     E * p = dynamic_cast< E* >( r.get() );
 872     return p? shared_ptr<T>( r, p ): shared_ptr<T>();
 873 }
 874
 875 template<class T, class U> shared_ptr<T> reinterpret_pointer_cast( shared_ptr<U> const & r ) BOOST_NOEXCEPT
 876 {
 877     (void) reinterpret_cast< T* >( static_cast< U* >( 0 ) );
 878
 879     typedef typename shared_ptr<T>::element_type E;
 880
 881     E * p = reinterpret_cast< E* >( r.get() );
 882     return shared_ptr<T>( r, p );
 883 }
 884
 885 // get_pointer() enables boost::mem_fn to recognize shared_ptr
 886
 887 template<class T> inline typename shared_ptr<T>::element_type * get_pointer(shared_ptr<T> const & p) BOOST_NOEXCEPT
 888 {
 889     return p.get();
 890 }
 891
 892 // operator<<
 893
 894 #if !defined(BOOST_NO_IOSTREAM)
 895
 896 #if defined(BOOST_NO_TEMPLATED_IOSTREAMS) || ( defined(__GNUC__) &&  (__GNUC__ < 3) )
 897
 898 template<class Y> std::ostream & operator<< (std::ostream & os, shared_ptr<Y> const & p)
 899 {
 900     os << p.get();
 901     return os;
 902 }
 903
 904 #else
 905
 906 // in STLport's no-iostreams mode no iostream symbols can be used
 907 #ifndef _STLP_NO_IOSTREAMS
 908
 909 # if defined(BOOST_MSVC) && BOOST_WORKAROUND(BOOST_MSVC, < 1300 && __SGI_STL_PORT)
 910 // MSVC6 has problems finding std::basic_ostream through the using declaration in namespace _STL
 911 using std::basic_ostream;
 912 template<class E, class T, class Y> basic_ostream<E, T> & operator<< (basic_ostream<E, T> & os, shared_ptr<Y> const & p)
 913 # else
 914 template<class E, class T, class Y> std::basic_ostream<E, T> & operator<< (std::basic_ostream<E, T> & os, shared_ptr<Y> const & p)
 915 # endif
 916 {
 917     os << p.get();
 918     return os;
 919 }
 920
 921 #endif // _STLP_NO_IOSTREAMS
 922
 923 #endif // __GNUC__ < 3
 924
 925 #endif // !defined(BOOST_NO_IOSTREAM)
 926
 927 // get_deleter
 928
 929 namespace detail
 930 {
 931
 932 #if ( defined(__GNUC__) && BOOST_WORKAROUND(__GNUC__, < 3) ) || \
 933     ( defined(__EDG_VERSION__) && BOOST_WORKAROUND(__EDG_VERSION__, <= 238) ) || \
 934     ( defined(__HP_aCC) && BOOST_WORKAROUND(__HP_aCC, <= 33500) )
 935
 936 // g++ 2.9x doesn't allow static_cast<X const *>(void *)
 937 // apparently EDG 2.38 and HP aCC A.03.35 also don't accept it
 938
 939 template<class D, class T> D * basic_get_deleter(shared_ptr<T> const & p)
 940 {
 941     void const * q = p._internal_get_deleter(BOOST_SP_TYPEID(D));
 942     return const_cast<D *>(static_cast<D const *>(q));
 943 }
 944
 945 #else
 946
 947 template<class D, class T> D * basic_get_deleter( shared_ptr<T> const & p ) BOOST_NOEXCEPT
 948 {
 949     return static_cast<D *>( p._internal_get_deleter(BOOST_SP_TYPEID(D)) );
 950 }
 951
 952 #endif
 953
 954 class esft2_deleter_wrapper
 955 {
 956 private:
 957
 958     shared_ptr<void const volatile> deleter_;
 959
 960 public:
 961
 962     esft2_deleter_wrapper()
 963     {
 964     }
 965
 966     template< class T > void set_deleter( shared_ptr<T> const & deleter )
 967     {
 968         deleter_ = deleter;
 969     }
 970
 971     template<typename D> D* get_deleter() const BOOST_NOEXCEPT
 972     {
 973         return boost::detail::basic_get_deleter<D>( deleter_ );
 974     }
 975
 976     template< class T> void operator()( T* )
 977     {
 978         BOOST_ASSERT( deleter_.use_count() <= 1 );
 979         deleter_.reset();
 980     }
 981 };
 982
 983 } // namespace detail
 984
 985 template<class D, class T> D * get_deleter( shared_ptr<T> const & p ) BOOST_NOEXCEPT
 986 {
 987     D *del = boost::detail::basic_get_deleter<D>(p);
 988
 989     if(del == 0)
 990     {
 991         boost::detail::esft2_deleter_wrapper *del_wrapper = boost::detail::basic_get_deleter<boost::detail::esft2_deleter_wrapper>(p);
 992 // The following get_deleter method call is fully qualified because
 993 // older versions of gcc (2.95, 3.2.3) fail to compile it when written del_wrapper->get_deleter<D>()
 994         if(del_wrapper) del = del_wrapper->::boost::detail::esft2_deleter_wrapper::get_deleter<D>();
 995     }
 996
 997     return del;
 998 }
 999
1000 // atomic access
1001
1002 #if !defined(BOOST_SP_NO_ATOMIC_ACCESS)
1003
1004 template<class T> inline bool atomic_is_lock_free( shared_ptr<T> const * /*p*/ ) BOOST_NOEXCEPT
1005 {
1006     return false;
1007 }
1008
1009 template<class T> shared_ptr<T> atomic_load( shared_ptr<T> const * p )
1010 {
1011     boost::detail::spinlock_pool<2>::scoped_lock lock( p );
1012     return *p;
1013 }
1014
1015 template<class T> inline shared_ptr<T> atomic_load_explicit( shared_ptr<T> const * p, /*memory_order mo*/ int )
1016 {
1017     return atomic_load( p );
1018 }
1019
1020 template<class T> void atomic_store( shared_ptr<T> * p, shared_ptr<T> r )
1021 {
1022     boost::detail::spinlock_pool<2>::scoped_lock lock( p );
1023     p->swap( r );
1024 }
1025
1026 template<class T> inline void atomic_store_explicit( shared_ptr<T> * p, shared_ptr<T> r, /*memory_order mo*/ int )
1027 {
1028     atomic_store( p, r ); // std::move( r )
1029 }
1030
1031 template<class T> shared_ptr<T> atomic_exchange( shared_ptr<T> * p, shared_ptr<T> r )
1032 {
1033     boost::detail::spinlock & sp = boost::detail::spinlock_pool<2>::spinlock_for( p );
1034
1035     sp.lock();
1036     p->swap( r );
1037     sp.unlock();
1038
1039     return r; // return std::move( r )
1040 }
1041
1042 template<class T> shared_ptr<T> atomic_exchange_explicit( shared_ptr<T> * p, shared_ptr<T> r, /*memory_order mo*/ int )
1043 {
1044     return atomic_exchange( p, r ); // std::move( r )
1045 }
1046
1047 template<class T> bool atomic_compare_exchange( shared_ptr<T> * p, shared_ptr<T> * v, shared_ptr<T> w )
1048 {
1049     boost::detail::spinlock & sp = boost::detail::spinlock_pool<2>::spinlock_for( p );
1050
1051     sp.lock();
1052
1053     if( p->_internal_equiv( *v ) )
1054     {
1055         p->swap( w );
1056
1057         sp.unlock();
1058
1059         return true;
1060     }
1061     else
1062     {
1063         shared_ptr<T> tmp( *p );
1064
1065         sp.unlock();
1066
1067         tmp.swap( *v );
1068         return false;
1069     }
1070 }
1071
1072 template<class T> inline bool atomic_compare_exchange_explicit( shared_ptr<T> * p, shared_ptr<T> * v, shared_ptr<T> w, /*memory_order success*/ int, /*memory_order failure*/ int )
1073 {
1074     return atomic_compare_exchange( p, v, w ); // std::move( w )
1075 }
1076
1077 #endif // !defined(BOOST_SP_NO_ATOMIC_ACCESS)
1078
1079 // hash_value
1080
1081 template< class T > struct hash;
1082
1083 template< class T > std::size_t hash_value( boost::shared_ptr<T> const & p ) BOOST_NOEXCEPT
1084 {
1085     return boost::hash< typename boost::shared_ptr<T>::element_type* >()( p.get() );
1086 }
1087
1088 } // namespace boost
1089
1090 #if defined( BOOST_SP_DISABLE_DEPRECATED )
1091 #pragma GCC diagnostic pop
1092 #endif
1093
1094 #endif  // #ifndef BOOST_SMART_PTR_SHARED_PTR_HPP_INCLUDED