// shared_ptr.hpp
//
// (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
-// Copyright (c) 2001, 2002 Peter Dimov
+// Copyright (c) 2001-2006 Peter Dimov
//
-// Permission to copy, use, modify, sell and distribute this software
-// is granted provided this copyright notice appears in all copies.
-// This software is provided "as is" without express or implied
-// warranty, and with no claim as to its suitability for any purpose.
+// Distributed under 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/smart_ptr/shared_ptr.htm for documentation.
//
#include <boost/detail/shared_ptr_nmt.hpp>
#else
+#include <memory> // for std::auto_ptr
+
#include <boost/assert.hpp>
#include <boost/checked_delete.hpp>
#include <boost/throw_exception.hpp>
#include <boost/detail/shared_count.hpp>
+#include <boost/detail/workaround.hpp>
-#include <memory> // for std::auto_ptr
-#include <algorithm> // for std::swap
-#include <functional> // for std::less
-#include <typeinfo> // for std::bad_cast
+#include <algorithm> // for std::swap
+#include <functional> // for std::less
+#include <typeinfo> // for std::bad_cast
+#include <iosfwd> // for std::basic_ostream
#ifdef BOOST_MSVC // moved here to work around VC++ compiler crash
# pragma warning(push)
namespace boost
{
+template<class T> class weak_ptr;
+template<class T> class enable_shared_from_this;
+
namespace detail
{
struct static_cast_tag {};
+struct const_cast_tag {};
struct dynamic_cast_tag {};
struct polymorphic_cast_tag {};
-template<typename T> struct shared_ptr_traits
+template<class T> struct shared_ptr_traits
{
typedef T & reference;
};
typedef void reference;
};
+template<> struct shared_ptr_traits<void volatile>
+{
+ typedef void reference;
+};
+
+template<> struct shared_ptr_traits<void const volatile>
+{
+ typedef void reference;
+};
+
+#endif
+
+// enable_shared_from_this support
+
+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 )
+{
+ if(pe != 0) pe->_internal_weak_this._internal_assign(const_cast<Y*>(px), pn);
+}
+
+#ifdef sgi
+// Turn off: the last argument of the varargs function "sp_enable_shared_from_this" is unnamed
+# pragma set woff 3506
+#endif
+
+inline void sp_enable_shared_from_this( shared_count const & /*pn*/, ... )
+{
+}
+
+#ifdef sgi
+# pragma reset woff 3506
+#endif
+
+#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION ) && !defined( BOOST_NO_AUTO_PTR )
+
+// rvalue auto_ptr support based on a technique by Dave Abrahams
+
+template< class T, class R > struct sp_enable_if_auto_ptr
+{
+};
+
+template< class T, class R > struct sp_enable_if_auto_ptr< std::auto_ptr< T >, R >
+{
+ typedef R type;
+};
+
#endif
} // namespace detail
// is destroyed or reset.
//
-template<typename T> class weak_ptr;
-template<typename T> class intrusive_ptr;
-
-template<typename T> class shared_ptr
+template<class T> class shared_ptr
{
private:
- // Borland 5.5.1 specific workarounds
-// typedef checked_deleter<T> deleter;
+ // Borland 5.5.1 specific workaround
typedef shared_ptr<T> this_type;
public:
typedef T element_type;
typedef T value_type;
+ typedef T * pointer;
+ typedef typename boost::detail::shared_ptr_traits<T>::reference reference;
- shared_ptr(): px(0), pn()
+ shared_ptr(): px(0), pn() // never throws in 1.30+
{
}
- template<typename Y>
- explicit shared_ptr(Y * p): px(p), pn(p, checked_deleter<Y>(), p) // Y must be complete
+ template<class Y>
+ explicit shared_ptr( Y * p ): px( p ), pn( p ) // Y must be complete
{
+ boost::detail::sp_enable_shared_from_this( pn, p, p );
}
//
// shared_ptr will release p by calling d(p)
//
- template<typename Y, typename D> shared_ptr(Y * p, D d): px(p), pn(p, d)
+ template<class Y, class D> shared_ptr(Y * p, D d): px(p), pn(p, d)
+ {
+ boost::detail::sp_enable_shared_from_this( pn, p, p );
+ }
+
+ // As above, but with allocator. A's copy constructor shall not throw.
+
+ template<class Y, class D, class A> shared_ptr( Y * p, D d, A a ): px( p ), pn( p, d, a )
{
+ boost::detail::sp_enable_shared_from_this( pn, p, p );
}
-// generated copy constructor, assignment, destructor are fine
+// generated copy constructor, assignment, destructor are fine...
+
+// except that Borland C++ has a bug, and g++ with -Wsynth warns
+#if defined(__BORLANDC__) || defined(__GNUC__)
- template<typename Y>
- explicit shared_ptr(weak_ptr<Y> const & r): px(r.px), pn(r.pn) // may throw
+ shared_ptr & operator=(shared_ptr const & r) // never throws
{
+ px = r.px;
+ pn = r.pn; // shared_count::op= doesn't throw
+ return *this;
+ }
+
+#endif
+
+ template<class Y>
+ explicit shared_ptr(weak_ptr<Y> const & r): pn(r.pn) // may throw
+ {
+ // it is now safe to copy r.px, as pn(r.pn) did not throw
+ px = r.px;
}
- template<typename Y>
+ template<class Y>
shared_ptr(shared_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws
{
}
- template<typename Y>
- shared_ptr(intrusive_ptr<Y> const & r): px(r.get()), pn(r.get()) // never throws
+ template<class Y>
+ shared_ptr(shared_ptr<Y> const & r, boost::detail::static_cast_tag): px(static_cast<element_type *>(r.px)), pn(r.pn)
{
}
- template<typename Y>
- shared_ptr(shared_ptr<Y> const & r, detail::static_cast_tag): px(static_cast<element_type *>(r.px)), pn(r.pn)
+ template<class Y>
+ shared_ptr(shared_ptr<Y> const & r, boost::detail::const_cast_tag): px(const_cast<element_type *>(r.px)), pn(r.pn)
{
}
- template<typename Y>
- shared_ptr(shared_ptr<Y> const & r, detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
+ template<class Y>
+ shared_ptr(shared_ptr<Y> const & r, boost::detail::dynamic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
{
- if (px == 0) // need to allocate new counter -- the cast failed
+ if(px == 0) // need to allocate new counter -- the cast failed
{
- pn = detail::shared_count();
+ pn = boost::detail::shared_count();
}
}
- template<typename Y>
- shared_ptr(shared_ptr<Y> const & r, detail::polymorphic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
+ template<class Y>
+ shared_ptr(shared_ptr<Y> const & r, boost::detail::polymorphic_cast_tag): px(dynamic_cast<element_type *>(r.px)), pn(r.pn)
{
- if (px == 0)
+ if(px == 0)
{
boost::throw_exception(std::bad_cast());
}
#ifndef BOOST_NO_AUTO_PTR
- template<typename Y>
- explicit shared_ptr(std::auto_ptr<Y> & r): px(r.get()), pn(r)
+ template<class Y>
+ explicit shared_ptr(std::auto_ptr<Y> & r): px(r.get()), pn()
{
+ Y * tmp = r.get();
+ pn = boost::detail::shared_count(r);
+ boost::detail::sp_enable_shared_from_this( pn, tmp, tmp );
}
-#endif
+#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
+
+ template<class Ap>
+ explicit shared_ptr( Ap r, typename boost::detail::sp_enable_if_auto_ptr<Ap, int>::type = 0 ): px( r.get() ), pn()
+ {
+ typename Ap::element_type * tmp = r.get();
+ pn = boost::detail::shared_count( r );
+ boost::detail::sp_enable_shared_from_this( pn, tmp, tmp );
+ }
-#if !defined(BOOST_MSVC) || (BOOST_MSVC > 1200)
- template<typename Y>
+#endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+
+#endif // BOOST_NO_AUTO_PTR
+
+#if !defined(BOOST_MSVC) || (BOOST_MSVC >= 1300)
+
+ template<class Y>
shared_ptr & operator=(shared_ptr<Y> const & r) // never throws
{
px = r.px;
#ifndef BOOST_NO_AUTO_PTR
- template<typename Y>
- shared_ptr & operator=(std::auto_ptr<Y> & r)
+ template<class Y>
+ shared_ptr & operator=( std::auto_ptr<Y> & r )
{
this_type(r).swap(*this);
return *this;
}
-#endif
+#if !defined( BOOST_NO_SFINAE ) && !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
+
+ template<class Ap>
+ typename boost::detail::sp_enable_if_auto_ptr< Ap, shared_ptr & >::type operator=( Ap r )
+ {
+ this_type( r ).swap( *this );
+ return *this;
+ }
+
+
+#endif // BOOST_NO_SFINAE, BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+
+#endif // BOOST_NO_AUTO_PTR
- void reset()
+ void reset() // never throws in 1.30+
{
this_type().swap(*this);
}
- template<typename Y> void reset(Y * p) // Y must be complete
+ template<class Y> void reset(Y * p) // Y must be complete
{
BOOST_ASSERT(p == 0 || p != px); // catch self-reset errors
this_type(p).swap(*this);
}
- template<typename Y, typename D> void reset(Y * p, D d)
+ template<class Y, class D> void reset( Y * p, D d )
{
- this_type(p, d).swap(*this);
+ this_type( p, d ).swap( *this );
}
- typename detail::shared_ptr_traits<T>::reference operator* () const // never throws
+ template<class Y, class D, class A> void reset( Y * p, D d, A a )
+ {
+ this_type( p, d, a ).swap( *this );
+ }
+
+ reference operator* () const // never throws
{
BOOST_ASSERT(px != 0);
return *px;
// implicit conversion to "bool"
- typedef T * (this_type::*unspecified_bool_type)() const;
+#if defined(__SUNPRO_CC) && BOOST_WORKAROUND(__SUNPRO_CC, <= 0x580)
+
+ operator bool () const
+ {
+ return px != 0;
+ }
+
+#elif defined( _MANAGED )
+
+ static void unspecified_bool( this_type*** )
+ {
+ }
+
+ typedef void (*unspecified_bool_type)( this_type*** );
+
+ operator unspecified_bool_type() const // never throws
+ {
+ return px == 0? 0: unspecified_bool;
+ }
+
+#elif \
+ ( defined(__MWERKS__) && BOOST_WORKAROUND(__MWERKS__, < 0x3200) ) || \
+ ( defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 304) )
+ typedef T * (this_type::*unspecified_bool_type)() const;
+
operator unspecified_bool_type() const // never throws
{
return px == 0? 0: &this_type::get;
}
+#else
+
+ typedef T * this_type::*unspecified_bool_type;
+
+ operator unspecified_bool_type() const // never throws
+ {
+ return px == 0? 0: &this_type::px;
+ }
+
+#endif
+
+ // operator! is redundant, but some compilers need it
+
bool operator! () const // never throws
{
return px == 0;
pn.swap(other.pn);
}
+ template<class Y> bool _internal_less(shared_ptr<Y> const & rhs) const
+ {
+ return pn < rhs.pn;
+ }
+
+ void * _internal_get_deleter(std::type_info const & ti) const
+ {
+ return pn.get_deleter(ti);
+ }
+
// Tasteless as this may seem, making all members public allows member templates
// to work in the absence of member template friends. (Matthew Langston)
private:
- template<typename Y> friend class shared_ptr;
- template<typename Y> friend class weak_ptr;
+ template<class Y> friend class shared_ptr;
+ template<class Y> friend class weak_ptr;
#endif
T * px; // contained pointer
- detail::shared_count pn; // reference counter
+ boost::detail::shared_count pn; // reference counter
}; // shared_ptr
-template<typename T, typename U> inline bool operator==(shared_ptr<T> const & a, shared_ptr<U> const & b)
+template<class T, class U> inline bool operator==(shared_ptr<T> const & a, shared_ptr<U> const & b)
{
return a.get() == b.get();
}
-template<typename T, typename U> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<U> const & b)
+template<class T, class U> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<U> const & b)
{
return a.get() != b.get();
}
// Resolve the ambiguity between our op!= and the one in rel_ops
-template<typename T> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<T> const & b)
+template<class T> inline bool operator!=(shared_ptr<T> const & a, shared_ptr<T> const & b)
{
return a.get() != b.get();
}
#endif
-template<typename T> inline bool operator<(shared_ptr<T> const & a, shared_ptr<T> const & b)
+template<class T, class U> inline bool operator<(shared_ptr<T> const & a, shared_ptr<U> const & b)
{
- return std::less<T*>()(a.get(), b.get());
+ return a._internal_less(b);
}
-template<typename T> inline void swap(shared_ptr<T> & a, shared_ptr<T> & b)
+template<class T> inline void swap(shared_ptr<T> & a, shared_ptr<T> & b)
{
a.swap(b);
}
-template<typename T, typename U> shared_ptr<T> shared_static_cast(shared_ptr<U> const & r)
+template<class T, class U> shared_ptr<T> static_pointer_cast(shared_ptr<U> const & r)
{
- return shared_ptr<T>(r, detail::static_cast_tag());
+ return shared_ptr<T>(r, boost::detail::static_cast_tag());
}
-template<typename T, typename U> shared_ptr<T> shared_dynamic_cast(shared_ptr<U> const & r)
+template<class T, class U> shared_ptr<T> const_pointer_cast(shared_ptr<U> const & r)
{
- return shared_ptr<T>(r, detail::dynamic_cast_tag());
+ return shared_ptr<T>(r, boost::detail::const_cast_tag());
}
-template<typename T, typename U> shared_ptr<T> shared_polymorphic_cast(shared_ptr<U> const & r)
+template<class T, class U> shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const & r)
+{
+ return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());
+}
+
+// shared_*_cast names are deprecated. Use *_pointer_cast instead.
+
+template<class T, class U> shared_ptr<T> shared_static_cast(shared_ptr<U> const & r)
{
- return shared_ptr<T>(r, detail::polymorphic_cast_tag());
+ return shared_ptr<T>(r, boost::detail::static_cast_tag());
}
-template<typename T, typename U> shared_ptr<T> shared_polymorphic_downcast(shared_ptr<U> const & r)
+template<class T, class U> shared_ptr<T> shared_dynamic_cast(shared_ptr<U> const & r)
+{
+ return shared_ptr<T>(r, boost::detail::dynamic_cast_tag());
+}
+
+template<class T, class U> shared_ptr<T> shared_polymorphic_cast(shared_ptr<U> const & r)
+{
+ return shared_ptr<T>(r, boost::detail::polymorphic_cast_tag());
+}
+
+template<class T, class U> shared_ptr<T> shared_polymorphic_downcast(shared_ptr<U> const & r)
{
BOOST_ASSERT(dynamic_cast<T *>(r.get()) == r.get());
return shared_static_cast<T>(r);
// get_pointer() enables boost::mem_fn to recognize shared_ptr
-template<typename T> inline T * get_pointer(shared_ptr<T> const & p)
+template<class T> inline T * get_pointer(shared_ptr<T> const & p)
{
return p.get();
}
-// shared_from_this() creates a shared_ptr from a raw pointer (usually 'this')
+// operator<<
-namespace detail
+#if defined(__GNUC__) && (__GNUC__ < 3)
+
+template<class Y> std::ostream & operator<< (std::ostream & os, shared_ptr<Y> const & p)
{
+ os << p.get();
+ return os;
+}
+
+#else
-inline void sp_assert_counted_base(boost::counted_base const *)
+// in STLport's no-iostreams mode no iostream symbols can be used
+#ifndef _STLP_NO_IOSTREAMS
+
+# if defined(BOOST_MSVC) && BOOST_WORKAROUND(BOOST_MSVC, < 1300 && __SGI_STL_PORT)
+// MSVC6 has problems finding std::basic_ostream through the using declaration in namespace _STL
+using std::basic_ostream;
+template<class E, class T, class Y> basic_ostream<E, T> & operator<< (basic_ostream<E, T> & os, shared_ptr<Y> const & p)
+# else
+template<class E, class T, class Y> std::basic_ostream<E, T> & operator<< (std::basic_ostream<E, T> & os, shared_ptr<Y> const & p)
+# endif
{
+ os << p.get();
+ return os;
}
-template<class T> inline T * sp_remove_const(T const * p)
+#endif // _STLP_NO_IOSTREAMS
+
+#endif // __GNUC__ < 3
+
+// get_deleter (experimental)
+
+#if ( defined(__GNUC__) && BOOST_WORKAROUND(__GNUC__, < 3) ) || \
+ ( defined(__EDG_VERSION__) && BOOST_WORKAROUND(__EDG_VERSION__, <= 238) ) || \
+ ( defined(__HP_aCC) && BOOST_WORKAROUND(__HP_aCC, <= 33500) )
+
+// g++ 2.9x doesn't allow static_cast<X const *>(void *)
+// apparently EDG 2.38 and HP aCC A.03.35 also don't accept it
+
+template<class D, class T> D * get_deleter(shared_ptr<T> const & p)
{
- return const_cast<T *>(p);
+ void const * q = p._internal_get_deleter(typeid(D));
+ return const_cast<D *>(static_cast<D const *>(q));
}
-} // namespace detail
+#else
-template<class T> shared_ptr<T> shared_from_this(T * p)
+template<class D, class T> D * get_deleter(shared_ptr<T> const & p)
{
- detail::sp_assert_counted_base(p);
- return shared_ptr<T>(detail::sp_remove_const(p));
+ return static_cast<D *>(p._internal_get_deleter(typeid(D)));
}
+#endif
+
} // namespace boost
#ifdef BOOST_MSVC