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Diffstat (limited to 'src/third_party/boost-1.69.0/boost/smart_ptr/enable_shared_from_this.hpp')
-rw-r--r-- | src/third_party/boost-1.69.0/boost/smart_ptr/enable_shared_from_this.hpp | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/src/third_party/boost-1.69.0/boost/smart_ptr/enable_shared_from_this.hpp b/src/third_party/boost-1.69.0/boost/smart_ptr/enable_shared_from_this.hpp new file mode 100644 index 00000000000..fc4de0b5712 --- /dev/null +++ b/src/third_party/boost-1.69.0/boost/smart_ptr/enable_shared_from_this.hpp @@ -0,0 +1,90 @@ +#ifndef BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED +#define BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED + +// +// enable_shared_from_this.hpp +// +// Copyright 2002, 2009 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 +// +// See http://www.boost.org/libs/smart_ptr/ for documentation. +// + +#include <boost/smart_ptr/weak_ptr.hpp> +#include <boost/smart_ptr/shared_ptr.hpp> +#include <boost/smart_ptr/detail/sp_noexcept.hpp> +#include <boost/assert.hpp> +#include <boost/config.hpp> + +namespace boost +{ + +template<class T> class enable_shared_from_this +{ +protected: + + BOOST_CONSTEXPR enable_shared_from_this() BOOST_SP_NOEXCEPT + { + } + + BOOST_CONSTEXPR enable_shared_from_this(enable_shared_from_this const &) BOOST_SP_NOEXCEPT + { + } + + enable_shared_from_this & operator=(enable_shared_from_this const &) BOOST_SP_NOEXCEPT + { + return *this; + } + + ~enable_shared_from_this() BOOST_SP_NOEXCEPT // ~weak_ptr<T> newer throws, so this call also must not throw + { + } + +public: + + shared_ptr<T> shared_from_this() + { + shared_ptr<T> p( weak_this_ ); + BOOST_ASSERT( p.get() == this ); + return p; + } + + shared_ptr<T const> shared_from_this() const + { + shared_ptr<T const> p( weak_this_ ); + BOOST_ASSERT( p.get() == this ); + return p; + } + + weak_ptr<T> weak_from_this() BOOST_SP_NOEXCEPT + { + return weak_this_; + } + + weak_ptr<T const> weak_from_this() const BOOST_SP_NOEXCEPT + { + return weak_this_; + } + +public: // actually private, but avoids compiler template friendship issues + + // Note: invoked automatically by shared_ptr; do not call + template<class X, class Y> void _internal_accept_owner( shared_ptr<X> const * ppx, Y * py ) const BOOST_SP_NOEXCEPT + { + if( weak_this_.expired() ) + { + weak_this_ = shared_ptr<T>( *ppx, py ); + } + } + +private: + + mutable weak_ptr<T> weak_this_; +}; + +} // namespace boost + +#endif // #ifndef BOOST_SMART_PTR_ENABLE_SHARED_FROM_THIS_HPP_INCLUDED |