williamr@2: #ifndef BOOST_SHARED_PTR_HPP_INCLUDED
williamr@2: #define BOOST_SHARED_PTR_HPP_INCLUDED
williamr@2: 
williamr@2: //
williamr@2: //  shared_ptr.hpp
williamr@2: //
williamr@2: //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
williamr@2: //  Copyright (c) 2001-2006 Peter Dimov
williamr@2: //
williamr@2: //  Distributed under the Boost Software License, Version 1.0. (See
williamr@2: //  accompanying file LICENSE_1_0.txt or copy at
williamr@2: //  http://www.boost.org/LICENSE_1_0.txt)
williamr@2: //
williamr@2: //  See http://www.boost.org/libs/smart_ptr/shared_ptr.htm for documentation.
williamr@2: //
williamr@2: 
williamr@2: #include <boost/config.hpp>   // for broken compiler workarounds
williamr@2: 
williamr@2: #if defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES)
williamr@2: #include <boost/detail/shared_ptr_nmt.hpp>
williamr@2: #else
williamr@2: 
williamr@2: #include <memory>               // for std::auto_ptr
williamr@2: 
williamr@2: #include <boost/assert.hpp>
williamr@2: #include <boost/checked_delete.hpp>
williamr@2: #include <boost/throw_exception.hpp>
williamr@2: #include <boost/detail/shared_count.hpp>
williamr@2: #include <boost/detail/workaround.hpp>
williamr@2: 
williamr@2: #include <algorithm>            // for std::swap
williamr@2: #include <functional>           // for std::less
williamr@2: #include <typeinfo>             // for std::bad_cast
williamr@2: #include <iosfwd>               // for std::basic_ostream
williamr@2: 
williamr@2: #ifdef BOOST_MSVC  // moved here to work around VC++ compiler crash
williamr@2: # pragma warning(push)
williamr@2: # pragma warning(disable:4284) // odd return type for operator->
williamr@2: #endif
williamr@2: 
williamr@2: namespace boost
williamr@2: {
williamr@2: 
williamr@2: template<class T> class weak_ptr;
williamr@2: template<class T> class enable_shared_from_this;
williamr@2: 
williamr@2: namespace detail
williamr@2: {
williamr@2: 
williamr@2: struct static_cast_tag {};
williamr@2: struct const_cast_tag {};
williamr@2: struct dynamic_cast_tag {};
williamr@2: struct polymorphic_cast_tag {};
williamr@2: 
williamr@2: template<class T> struct shared_ptr_traits
williamr@2: {
williamr@2:     typedef T & reference;
williamr@2: };
williamr@2: 
williamr@2: template<> struct shared_ptr_traits<void>
williamr@2: {
williamr@2:     typedef void reference;
williamr@2: };
williamr@2: 
williamr@2: #if !defined(BOOST_NO_CV_VOID_SPECIALIZATIONS)
williamr@2: 
williamr@2: template<> struct shared_ptr_traits<void const>
williamr@2: {
williamr@2:     typedef void reference;
williamr@2: };
williamr@2: 
williamr@2: template<> struct shared_ptr_traits<void volatile>
williamr@2: {
williamr@2:     typedef void reference;
williamr@2: };
williamr@2: 
williamr@2: template<> struct shared_ptr_traits<void const volatile>
williamr@2: {
williamr@2:     typedef void reference;
williamr@2: };
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2: // enable_shared_from_this support
williamr@2: 
williamr@2: template<class T, class Y> void sp_enable_shared_from_this( shared_count const & pn, boost::enable_shared_from_this<T> const * pe, Y const * px )
williamr@2: {
williamr@2:     if(pe != 0) pe->_internal_weak_this._internal_assign(const_cast<Y*>(px), pn);
williamr@2: }
williamr@2: 
williamr@2: #ifdef sgi
williamr@2: // Turn off: the last argument of the varargs function "sp_enable_shared_from_this" is unnamed
williamr@2: # pragma set woff 3506
williamr@2: #endif
williamr@2: 
williamr@2: inline void sp_enable_shared_from_this( shared_count const & /*pn*/, ... )
williamr@2: {
williamr@2: }
williamr@2: 
williamr@2: #ifdef sgi
williamr@2: # pragma reset woff 3506
williamr@2: #endif
williamr@2: 
williamr@2: #if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )
williamr@2: 
williamr@2: // rvalue auto_ptr support based on a technique by Dave Abrahams
williamr@2: 
williamr@2: template< class T, class R > struct sp_enable_if_auto_ptr
williamr@2: {
williamr@2: };
williamr@2: 
williamr@2: template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >
williamr@2: {
williamr@2:     typedef R type;
williamr@2: }; 
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2: } // namespace detail
williamr@2: 
williamr@2: 
williamr@2: //
williamr@2: //  shared_ptr
williamr@2: //
williamr@2: //  An enhanced relative of scoped_ptr with reference counted copy semantics.
williamr@2: //  The object pointed to is deleted when the last shared_ptr pointing to it
williamr@2: //  is destroyed or reset.
williamr@2: //
williamr@2: 
williamr@2: template<class T> class shared_ptr
williamr@2: {
williamr@2: private:
williamr@2: 
williamr@2:     // Borland 5.5.1 specific workaround
williamr@2:     typedef shared_ptr<T> this_type;
williamr@2: 
williamr@2: public:
williamr@2: 
williamr@2:     typedef T element_type;
williamr@2:     typedef T value_type;
williamr@2:     typedef T * pointer;
williamr@2:     typedef typename boost::detail::shared_ptr_traits<T>::reference reference;
williamr@2: 
williamr@2:     shared_ptr(): px(0), pn() // never throws in 1.30+
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     explicit shared_ptr( Y * p ): px( p ), pn( p ) // Y must be complete
williamr@2:     {
williamr@2:         boost::detail::sp_enable_shared_from_this( pn, p, p );
williamr@2:     }
williamr@2: 
williamr@2:     //
williamr@2:     // Requirements: D's copy constructor must not throw
williamr@2:     //
williamr@2:     // shared_ptr will release p by calling d(p)
williamr@2:     //
williamr@2: 
williamr@2:     template<class Y, class D> shared_ptr(Y * p, D d): px(p), pn(p, d)
williamr@2:     {
williamr@2:         boost::detail::sp_enable_shared_from_this( pn, p, p );
williamr@2:     }
williamr@2: 
williamr@2:     // As above, but with allocator. A's copy constructor shall not throw.
williamr@2: 
williamr@2:     template<class Y, class D, class A> shared_ptr( Y * p, D d, A a ): px( p ), pn( p, d, a )
williamr@2:     {
williamr@2:         boost::detail::sp_enable_shared_from_this( pn, p, p );
williamr@2:     }
williamr@2: 
williamr@2: //  generated copy constructor, assignment, destructor are fine...
williamr@2: 
williamr@2: //  except that Borland C++ has a bug, and g++ with -Wsynth warns
williamr@2: #if defined(__BORLANDC__) || defined(__GNUC__)
williamr@2: 
williamr@2:     shared_ptr & operator=(shared_ptr const & r) // never throws
williamr@2:     {
williamr@2:         px = r.px;
williamr@2:         pn = r.pn; // shared_count::op= doesn't throw
williamr@2:         return *this;
williamr@2:     }
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     explicit shared_ptr(weak_ptr<Y> const & r): pn(r.pn) // may throw
williamr@2:     {
williamr@2:         // it is now safe to copy r.px, as pn(r.pn) did not throw
williamr@2:         px = r.px;
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr(shared_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr(shared_ptr<Y> const & r, boost::detail::static_cast_tag): px(static_cast<element_type *>(r.px)), pn(r.pn)
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr(shared_ptr<Y> const & r, boost::detail::const_cast_tag): px(const_cast<element_type *>(r.px)), pn(r.pn)
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr(shared_ptr<Y> const & r, boost::detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
williamr@2:     {
williamr@2:         if(px == 0) // need to allocate new counter -- the cast failed
williamr@2:         {
williamr@2:             pn = boost::detail::shared_count();
williamr@2:         }
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr(shared_ptr<Y> const & r, boost::detail::polymorphic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
williamr@2:     {
williamr@2:         if(px == 0)
williamr@2:         {
williamr@2:             boost::throw_exception(std::bad_cast());
williamr@2:         }
williamr@2:     }
williamr@2: 
williamr@2: #ifndef BOOST_NO_AUTO_PTR
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     explicit shared_ptr(std::auto_ptr<Y> & r): px(r.get()), pn()
williamr@2:     {
williamr@2:         Y * tmp = r.get();
williamr@2:         pn = boost::detail::shared_count(r);
williamr@2:         boost::detail::sp_enable_shared_from_this( pn, tmp, tmp );
williamr@2:     }
williamr@2: 
williamr@2: #if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
williamr@2: 
williamr@2:     template<class Ap>
williamr@2:     explicit shared_ptr( Ap r, typename boost::detail::sp_enable_if_auto_ptr<Ap, int>::type = 0 ): px( r.get() ), pn()
williamr@2:     {
williamr@2:         typename Ap::element_type * tmp = r.get();
williamr@2:         pn = boost::detail::shared_count( r );
williamr@2:         boost::detail::sp_enable_shared_from_this( pn, tmp, tmp );
williamr@2:     }
williamr@2: 
williamr@2: 
williamr@2: #endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
williamr@2: 
williamr@2: #endif // BOOST_NO_AUTO_PTR
williamr@2: 
williamr@2: #if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1300)
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr & operator=(shared_ptr<Y> const & r) // never throws
williamr@2:     {
williamr@2:         px = r.px;
williamr@2:         pn = r.pn; // shared_count::op= doesn't throw
williamr@2:         return *this;
williamr@2:     }
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2: #ifndef BOOST_NO_AUTO_PTR
williamr@2: 
williamr@2:     template<class Y>
williamr@2:     shared_ptr & operator=( std::auto_ptr<Y> & r )
williamr@2:     {
williamr@2:         this_type(r).swap(*this);
williamr@2:         return *this;
williamr@2:     }
williamr@2: 
williamr@2: #if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
williamr@2: 
williamr@2:     template<class Ap>
williamr@2:     typename boost::detail::sp_enable_if_auto_ptr< Ap, shared_ptr & >::type operator=( Ap r )
williamr@2:     {
williamr@2:         this_type( r ).swap( *this );
williamr@2:         return *this;
williamr@2:     }
williamr@2: 
williamr@2: 
williamr@2: #endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
williamr@2: 
williamr@2: #endif // BOOST_NO_AUTO_PTR
williamr@2: 
williamr@2:     void reset() // never throws in 1.30+
williamr@2:     {
williamr@2:         this_type().swap(*this);
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y> void reset(Y * p) // Y must be complete
williamr@2:     {
williamr@2:         BOOST_ASSERT(p == 0 || p != px); // catch self-reset errors
williamr@2:         this_type(p).swap(*this);
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y, class D> void reset( Y * p, D d )
williamr@2:     {
williamr@2:         this_type( p, d ).swap( *this );
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y, class D, class A> void reset( Y * p, D d, A a )
williamr@2:     {
williamr@2:         this_type( p, d, a ).swap( *this );
williamr@2:     }
williamr@2: 
williamr@2:     reference operator* () const // never throws
williamr@2:     {
williamr@2:         BOOST_ASSERT(px != 0);
williamr@2:         return *px;
williamr@2:     }
williamr@2: 
williamr@2:     T * operator-> () const // never throws
williamr@2:     {
williamr@2:         BOOST_ASSERT(px != 0);
williamr@2:         return px;
williamr@2:     }
williamr@2:     
williamr@2:     T * get() const // never throws
williamr@2:     {
williamr@2:         return px;
williamr@2:     }
williamr@2: 
williamr@2:     // implicit conversion to "bool"
williamr@2: 
williamr@2: #if defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x580)
williamr@2: 
williamr@2:     operator bool () const
williamr@2:     {
williamr@2:         return px != 0;
williamr@2:     }
williamr@2: 
williamr@2: #elif defined( _MANAGED )
williamr@2: 
williamr@2:     static void unspecified_bool( this_type*** )
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2:     typedef void (*unspecified_bool_type)( this_type*** );
williamr@2: 
williamr@2:     operator unspecified_bool_type() const // never throws
williamr@2:     {
williamr@2:         return px == 0? 0: unspecified_bool;
williamr@2:     }
williamr@2: 
williamr@2: #elif \
williamr@2:     ( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \
williamr@2:     ( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) )
williamr@2: 
williamr@2:     typedef T * (this_type::*unspecified_bool_type)() const;
williamr@2:     
williamr@2:     operator unspecified_bool_type() const // never throws
williamr@2:     {
williamr@2:         return px == 0? 0: &this_type::get;
williamr@2:     }
williamr@2: 
williamr@2: #else 
williamr@2: 
williamr@2:     typedef T * this_type::*unspecified_bool_type;
williamr@2: 
williamr@2:     operator unspecified_bool_type() const // never throws
williamr@2:     {
williamr@2:         return px == 0? 0: &this_type::px;
williamr@2:     }
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2:     // operator! is redundant, but some compilers need it
williamr@2: 
williamr@2:     bool operator! () const // never throws
williamr@2:     {
williamr@2:         return px == 0;
williamr@2:     }
williamr@2: 
williamr@2:     bool unique() const // never throws
williamr@2:     {
williamr@2:         return pn.unique();
williamr@2:     }
williamr@2: 
williamr@2:     long use_count() const // never throws
williamr@2:     {
williamr@2:         return pn.use_count();
williamr@2:     }
williamr@2: 
williamr@2:     void swap(shared_ptr<T> & other) // never throws
williamr@2:     {
williamr@2:         std::swap(px, other.px);
williamr@2:         pn.swap(other.pn);
williamr@2:     }
williamr@2: 
williamr@2:     template<class Y> bool _internal_less(shared_ptr<Y> const & rhs) const
williamr@2:     {
williamr@2:         return pn < rhs.pn;
williamr@2:     }
williamr@2: 
williamr@2:     void * _internal_get_deleter(std::type_info const & ti) const
williamr@2:     {
williamr@2:         return pn.get_deleter(ti);
williamr@2:     }
williamr@2: 
williamr@2: // Tasteless as this may seem, making all members public allows member templates
williamr@2: // to work in the absence of member template friends. (Matthew Langston)
williamr@2: 
williamr@2: #ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
williamr@2: 
williamr@2: private:
williamr@2: 
williamr@2:     template<class Y> friend class shared_ptr;
williamr@2:     template<class Y> friend class weak_ptr;
williamr@2: 
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2:     T * px;                     // contained pointer
williamr@2:     boost::detail::shared_count pn;    // reference counter
williamr@2: 
williamr@2: };  // shared_ptr
williamr@2: 
williamr@2: template<class T, class U> inline bool operator==(shared_ptr<T> const & a, shared_ptr<U> const & b)
williamr@2: {
williamr@2:     return a.get() == b.get();
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<U> const & b)
williamr@2: {
williamr@2:     return a.get() != b.get();
williamr@2: }
williamr@2: 
williamr@2: #if __GNUC__ == 2 && __GNUC_MINOR__ <= 96
williamr@2: 
williamr@2: // Resolve the ambiguity between our op!= and the one in rel_ops
williamr@2: 
williamr@2: template<class T> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<T> const & b)
williamr@2: {
williamr@2:     return a.get() != b.get();
williamr@2: }
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2: template<class T, class U> inline bool operator<(shared_ptr<T> const & a, shared_ptr<U> const & b)
williamr@2: {
williamr@2:     return a._internal_less(b);
williamr@2: }
williamr@2: 
williamr@2: template<class T> inline void swap(shared_ptr<T> & a, shared_ptr<T> & b)
williamr@2: {
williamr@2:     a.swap(b);
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> static_pointer_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::static_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> const_pointer_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::const_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: // shared_*_cast names are deprecated. Use *_pointer_cast instead.
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> shared_static_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::static_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> shared_dynamic_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> shared_polymorphic_cast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     return shared_ptr<T>(r, boost::detail::polymorphic_cast_tag());
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> shared_ptr<T> shared_polymorphic_downcast(shared_ptr<U> const & r)
williamr@2: {
williamr@2:     BOOST_ASSERT(dynamic_cast<T *>(r.get()) == r.get());
williamr@2:     return shared_static_cast<T>(r);
williamr@2: }
williamr@2: 
williamr@2: // get_pointer() enables boost::mem_fn to recognize shared_ptr
williamr@2: 
williamr@2: template<class T> inline T * get_pointer(shared_ptr<T> const & p)
williamr@2: {
williamr@2:     return p.get();
williamr@2: }
williamr@2: 
williamr@2: // operator<<
williamr@2: 
williamr@2: #if defined(__GNUC__) &&  (__GNUC__ < 3)
williamr@2: 
williamr@2: template<class Y> std::ostream & operator<< (std::ostream & os, shared_ptr<Y> const & p)
williamr@2: {
williamr@2:     os << p.get();
williamr@2:     return os;
williamr@2: }
williamr@2: 
williamr@2: #else
williamr@2: 
williamr@2: // in STLport's no-iostreams mode no iostream symbols can be used
williamr@2: #ifndef _STLP_NO_IOSTREAMS
williamr@2: 
williamr@2: # if defined(BOOST_MSVC) && BOOST_WORKAROUND(BOOST_MSVC, < 1300 && __SGI_STL_PORT)
williamr@2: // MSVC6 has problems finding std::basic_ostream through the using declaration in namespace _STL
williamr@2: using std::basic_ostream;
williamr@2: template<class E, class T, class Y> basic_ostream<E, T> & operator<< (basic_ostream<E, T> & os, shared_ptr<Y> const & p)
williamr@2: # else
williamr@2: template<class E, class T, class Y> std::basic_ostream<E, T> & operator<< (std::basic_ostream<E, T> & os, shared_ptr<Y> const & p)
williamr@2: # endif 
williamr@2: {
williamr@2:     os << p.get();
williamr@2:     return os;
williamr@2: }
williamr@2: 
williamr@2: #endif // _STLP_NO_IOSTREAMS
williamr@2: 
williamr@2: #endif // __GNUC__ < 3
williamr@2: 
williamr@2: // get_deleter (experimental)
williamr@2: 
williamr@2: #if ( defined(__GNUC__) && BOOST_WORKAROUND(__GNUC__, < 3) ) || \
williamr@2:     ( defined(__EDG_VERSION__) && BOOST_WORKAROUND(__EDG_VERSION__, <= 238) ) || \
williamr@2:     ( defined(__HP_aCC) && BOOST_WORKAROUND(__HP_aCC, <= 33500) )
williamr@2: 
williamr@2: // g++ 2.9x doesn't allow static_cast<X const *>(void *)
williamr@2: // apparently EDG 2.38 and HP aCC A.03.35 also don't accept it
williamr@2: 
williamr@2: template<class D, class T> D * get_deleter(shared_ptr<T> const & p)
williamr@2: {
williamr@2:     void const * q = p._internal_get_deleter(typeid(D));
williamr@2:     return const_cast<D *>(static_cast<D const *>(q));
williamr@2: }
williamr@2: 
williamr@2: #else
williamr@2: 
williamr@2: template<class D, class T> D * get_deleter(shared_ptr<T> const & p)
williamr@2: {
williamr@2:     return static_cast<D *>(p._internal_get_deleter(typeid(D)));
williamr@2: }
williamr@2: 
williamr@2: #endif
williamr@2: 
williamr@2: } // namespace boost
williamr@2: 
williamr@2: #ifdef BOOST_MSVC
williamr@2: # pragma warning(pop)
williamr@2: #endif    
williamr@2: 
williamr@2: #endif  // #if defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES)
williamr@2: 
williamr@2: #endif  // #ifndef BOOST_SHARED_PTR_HPP_INCLUDED