diff --git a/include/boost/smart_ptr/shared_ptr.hpp b/include/boost/smart_ptr/shared_ptr.hpp index bcefda8..6c28973 100644 --- a/include/boost/smart_ptr/shared_ptr.hpp +++ b/include/boost/smart_ptr/shared_ptr.hpp @@ -642,6 +642,14 @@ public: return *this; } + // aliasing move + template + shared_ptr( shared_ptr && r, element_type * p ) BOOST_NOEXCEPT : px( p ), pn() + { + pn.swap( r.pn ); + r.px = 0; + } + #endif #if !defined( BOOST_NO_CXX11_NULLPTR ) diff --git a/shared_ptr.htm b/shared_ptr.htm index d58e1f5..5c756f8 100644 --- a/shared_ptr.htm +++ b/shared_ptr.htm @@ -139,6 +139,8 @@ void bad() template<class Y> shared_ptr(shared_ptr<Y> const & r, element_type * p); // never throws + template<class Y> shared_ptr(shared_ptr<Y> && r, element_type * p); // never throws + template<class Y> explicit shared_ptr(weak_ptr<Y> const & r); template<class Y> explicit shared_ptr(std::auto_ptr<Y> & r); @@ -352,6 +354,16 @@ template<class Y> shared_ptr(shared_ptr<Y> && r); // never t

Postconditions: get() == p && use_count() == r.use_count().

Throws: nothing.

+

aliasing move constructor

+
template<class Y> shared_ptr(shared_ptr<Y> && r, element_type * p); // never throws
+
+

+ Effects: Move-constructs a shared_ptr from r, while + storing p instead. +

+

Postconditions: get() == p and use_count() equals the old count of r. r is empty and r.get() == 0.

+

Throws: nothing.

+

weak_ptr constructor

template<class Y> explicit shared_ptr(weak_ptr<Y> const & r);
diff --git a/test/Jamfile.v2 b/test/Jamfile.v2 index 963eebc..d965bfd 100644 --- a/test/Jamfile.v2 +++ b/test/Jamfile.v2 @@ -34,6 +34,7 @@ import testing ; [ run shared_ptr_alias_test.cpp ] [ run shared_ptr_rv_test.cpp ] [ run shared_ptr_move_test.cpp ] + [ run shared_ptr_alias_move_test.cpp ] [ compile-fail shared_ptr_pv_fail.cpp ] [ run sp_unary_addr_test.cpp ] [ compile-fail scoped_ptr_eq_fail.cpp ] diff --git a/test/shared_ptr_alias_move_test.cpp b/test/shared_ptr_alias_move_test.cpp new file mode 100644 index 0000000..79b37dd --- /dev/null +++ b/test/shared_ptr_alias_move_test.cpp @@ -0,0 +1,105 @@ +#include + +// shared_ptr_alias_move_test.cpp +// +// Copyright (c) 2007 Peter Dimov +// +// 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) + + +#include +#include +#include + +#if !defined( BOOST_NO_CXX11_RVALUE_REFERENCES ) + +struct X +{ + static long instances; + + int v_; + + explicit X( int v ): v_( v ) + { + ++instances; + } + + ~X() + { + v_ = 0; + --instances; + } + +private: + X( X const & ); + X & operator=( X const & ); +}; + +long X::instances = 0; + +int main() +{ + BOOST_TEST( X::instances == 0 ); + + { + boost::shared_ptr< X > p( new X( 5 ) ); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.unique() ); + BOOST_TEST( p->v_ == 5 ); + + boost::shared_ptr< X > p2( std::move( p ), p.get() ); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.get() == 0 ); + BOOST_TEST( p2.unique() ); + BOOST_TEST( p2->v_ == 5 ); + + boost::shared_ptr< int const > p3( std::move( p2 ), &p2->v_ ); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p2.get() == 0 ); + BOOST_TEST( p3.unique() ); + BOOST_TEST( *p3 == 5 ); + + p3.reset(); + BOOST_TEST( X::instances == 0 ); + } + + { + boost::shared_ptr< X > p( new X( 5 ) ); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.unique() ); + BOOST_TEST( p->v_ == 5 ); + + { + boost::shared_ptr< X > p2(p); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.get() == p2.get() ); + BOOST_TEST( p.use_count() == 2 ); + BOOST_TEST( p2.use_count() == 2 ); + + boost::shared_ptr< int const > p3( std::move( p2 ), &p2->v_ ); + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.use_count() == 2 ); + BOOST_TEST( p2.use_count() == 0 ); + BOOST_TEST( p2.get() == 0 ); + BOOST_TEST( p3.use_count() == 2 ); + BOOST_TEST( p3.get() == &p->v_ ); + } + + BOOST_TEST( X::instances == 1 ); + BOOST_TEST( p.unique() ); + BOOST_TEST( p->v_ == 5 ); + } + + return boost::report_errors(); +} + +#else // defined( BOOST_NO_CXX11_RVALUE_REFERENCES ) + +int main() +{ + return 0; +} + +#endif