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Diffstat (limited to 'src/boost/weak_ptr.hpp')
-rw-r--r-- | src/boost/weak_ptr.hpp | 193 |
1 files changed, 0 insertions, 193 deletions
diff --git a/src/boost/weak_ptr.hpp b/src/boost/weak_ptr.hpp deleted file mode 100644 index 3d3b3eb79df1..000000000000 --- a/src/boost/weak_ptr.hpp +++ /dev/null @@ -1,193 +0,0 @@ -#ifndef BOOST_WEAK_PTR_HPP_INCLUDED -#define BOOST_WEAK_PTR_HPP_INCLUDED - -// -// weak_ptr.hpp -// -// Copyright (c) 2001, 2002, 2003 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. -// -// See http://www.boost.org/libs/smart_ptr/weak_ptr.htm for documentation. -// - -#include <boost/shared_ptr.hpp> - -#ifdef BOOST_MSVC // moved here to work around VC++ compiler crash -# pragma warning(push) -# pragma warning(disable:4284) // odd return type for operator-> -#endif - -namespace boost -{ - -template<class T> class weak_ptr -{ -private: - - // Borland 5.5.1 specific workarounds - typedef weak_ptr<T> this_type; - -public: - - typedef T element_type; - - weak_ptr(): px(0), pn() // never throws in 1.30+ - { - } - -// generated copy constructor, assignment, destructor are fine - - -// -// The "obvious" converting constructor implementation: -// -// template<class Y> -// weak_ptr(weak_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws -// { -// } -// -// has a serious problem. -// -// r.px may already have been invalidated. The px(r.px) -// conversion may require access to *r.px (virtual inheritance). -// -// It is not possible to avoid spurious access violations since -// in multithreaded programs r.px may be invalidated at any point. -// - - template<class Y> - weak_ptr(weak_ptr<Y> const & r): pn(r.pn) // never throws - { - px = r.lock().get(); - } - - template<class Y> - weak_ptr(shared_ptr<Y> const & r): px(r.px), pn(r.pn) // never throws - { - } - -#if !defined(BOOST_MSVC) || (BOOST_MSVC > 1200) - - template<class Y> - weak_ptr & operator=(weak_ptr<Y> const & r) // never throws - { - px = r.lock().get(); - pn = r.pn; - return *this; - } - - template<class Y> - weak_ptr & operator=(shared_ptr<Y> const & r) // never throws - { - px = r.px; - pn = r.pn; - return *this; - } - -#endif - - shared_ptr<T> lock() const // never throws - { -#if defined(BOOST_HAS_THREADS) - - // optimization: avoid throw overhead - if(expired()) - { - return shared_ptr<element_type>(); - } - - try - { - return shared_ptr<element_type>(*this); - } - catch(bad_weak_ptr const &) - { - // Q: how can we get here? - // A: another thread may have invalidated r after the use_count test above. - return shared_ptr<element_type>(); - } - -#else - - // optimization: avoid try/catch overhead when single threaded - return expired()? shared_ptr<element_type>(): shared_ptr<element_type>(*this); - -#endif - } - - long use_count() const // never throws - { - return pn.use_count(); - } - - bool expired() const // never throws - { - return pn.use_count() == 0; - } - - void reset() // never throws in 1.30+ - { - this_type().swap(*this); - } - - void swap(this_type & other) // never throws - { - std::swap(px, other.px); - pn.swap(other.pn); - } - - void _internal_assign(T * px2, detail::shared_count const & pn2) - { - px = px2; - pn = pn2; - } - - template<class Y> bool _internal_less(weak_ptr<Y> const & rhs) const - { - return pn < rhs.pn; - } - -// Tasteless as this may seem, making all members public allows member templates -// to work in the absence of member template friends. (Matthew Langston) - -#if 0 - -private: - - template<class Y> friend class weak_ptr; - template<class Y> friend class shared_ptr; - -#endif - - T * px; // contained pointer - detail::weak_count pn; // reference counter - -}; // weak_ptr - -template<class T, class U> inline bool operator<(weak_ptr<T> const & a, weak_ptr<U> const & b) -{ - return a._internal_less(b); -} - -template<class T> void swap(weak_ptr<T> & a, weak_ptr<T> & b) -{ - a.swap(b); -} - -// deprecated, provided for backward compatibility -template<class T> shared_ptr<T> make_shared(weak_ptr<T> const & r) -{ - return r.lock(); -} - -} // namespace boost - -#ifdef BOOST_MSVC -# pragma warning(pop) -#endif - -#endif // #ifndef BOOST_WEAK_PTR_HPP_INCLUDED |