| // <tr1_impl/boost_shared_ptr.h> -*- C++ -*- |
| |
| // Copyright (C) 2007 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 2, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING. If not, write to the Free |
| // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, |
| // USA. |
| |
| // As a special exception, you may use this file as part of a free software |
| // library without restriction. Specifically, if other files instantiate |
| // templates or use macros or inline functions from this file, or you compile |
| // this file and link it with other files to produce an executable, this |
| // file does not by itself cause the resulting executable to be covered by |
| // the GNU General Public License. This exception does not however |
| // invalidate any other reasons why the executable file might be covered by |
| // the GNU General Public License. |
| |
| // shared_count.hpp |
| // Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd. |
| |
| // shared_ptr.hpp |
| // Copyright (C) 1998, 1999 Greg Colvin and Beman Dawes. |
| // Copyright (C) 2001, 2002, 2003 Peter Dimov |
| |
| // weak_ptr.hpp |
| // Copyright (C) 2001, 2002, 2003 Peter Dimov |
| |
| // enable_shared_from_this.hpp |
| // Copyright (C) 2002 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) |
| |
| // GCC Note: based on version 1.32.0 of the Boost library. |
| |
| /** @file tr1_impl/boost_shared_ptr.h |
| * This is an internal header file, included by other library headers. |
| * You should not attempt to use it directly. |
| */ |
| |
| |
| namespace std |
| { |
| _GLIBCXX_BEGIN_NAMESPACE_TR1 |
| |
| template<_Lock_policy _Lp> |
| class __weak_count |
| { |
| public: |
| __weak_count() |
| : _M_pi(0) // nothrow |
| { } |
| |
| __weak_count(const __shared_count<_Lp>& __r) |
| : _M_pi(__r._M_pi) // nothrow |
| { |
| if (_M_pi != 0) |
| _M_pi->_M_weak_add_ref(); |
| } |
| |
| __weak_count(const __weak_count<_Lp>& __r) |
| : _M_pi(__r._M_pi) // nothrow |
| { |
| if (_M_pi != 0) |
| _M_pi->_M_weak_add_ref(); |
| } |
| |
| ~__weak_count() // nothrow |
| { |
| if (_M_pi != 0) |
| _M_pi->_M_weak_release(); |
| } |
| |
| __weak_count<_Lp>& |
| operator=(const __shared_count<_Lp>& __r) // nothrow |
| { |
| _Sp_counted_base<_Lp>* __tmp = __r._M_pi; |
| if (__tmp != 0) |
| __tmp->_M_weak_add_ref(); |
| if (_M_pi != 0) |
| _M_pi->_M_weak_release(); |
| _M_pi = __tmp; |
| return *this; |
| } |
| |
| __weak_count<_Lp>& |
| operator=(const __weak_count<_Lp>& __r) // nothrow |
| { |
| _Sp_counted_base<_Lp>* __tmp = __r._M_pi; |
| if (__tmp != 0) |
| __tmp->_M_weak_add_ref(); |
| if (_M_pi != 0) |
| _M_pi->_M_weak_release(); |
| _M_pi = __tmp; |
| return *this; |
| } |
| |
| void |
| _M_swap(__weak_count<_Lp>& __r) // nothrow |
| { |
| _Sp_counted_base<_Lp>* __tmp = __r._M_pi; |
| __r._M_pi = _M_pi; |
| _M_pi = __tmp; |
| } |
| |
| long |
| _M_get_use_count() const // nothrow |
| { return _M_pi != 0 ? _M_pi->_M_get_use_count() : 0; } |
| |
| friend inline bool |
| operator==(const __weak_count<_Lp>& __a, const __weak_count<_Lp>& __b) |
| { return __a._M_pi == __b._M_pi; } |
| |
| friend inline bool |
| operator<(const __weak_count<_Lp>& __a, const __weak_count<_Lp>& __b) |
| { return std::less<_Sp_counted_base<_Lp>*>()(__a._M_pi, __b._M_pi); } |
| |
| private: |
| friend class __shared_count<_Lp>; |
| |
| _Sp_counted_base<_Lp>* _M_pi; |
| }; |
| |
| // now that __weak_count is defined we can define this constructor: |
| template<_Lock_policy _Lp> |
| inline |
| __shared_count<_Lp>:: |
| __shared_count(const __weak_count<_Lp>& __r) |
| : _M_pi(__r._M_pi) |
| { |
| if (_M_pi != 0) |
| _M_pi->_M_add_ref_lock(); |
| else |
| __throw_bad_weak_ptr(); |
| } |
| |
| // Forward declarations. |
| template<typename _Tp, _Lock_policy _Lp = __default_lock_policy> |
| class __shared_ptr; |
| |
| template<typename _Tp, _Lock_policy _Lp = __default_lock_policy> |
| class __weak_ptr; |
| |
| template<typename _Tp, _Lock_policy _Lp = __default_lock_policy> |
| class __enable_shared_from_this; |
| |
| template<typename _Tp> |
| class shared_ptr; |
| |
| template<typename _Tp> |
| class weak_ptr; |
| |
| template<typename _Tp> |
| class enable_shared_from_this; |
| |
| // Support for enable_shared_from_this. |
| |
| // Friend of __enable_shared_from_this. |
| template<_Lock_policy _Lp, typename _Tp1, typename _Tp2> |
| void |
| __enable_shared_from_this_helper(const __shared_count<_Lp>&, |
| const __enable_shared_from_this<_Tp1, |
| _Lp>*, const _Tp2*); |
| |
| // Friend of enable_shared_from_this. |
| template<typename _Tp1, typename _Tp2> |
| void |
| __enable_shared_from_this_helper(const __shared_count<>&, |
| const enable_shared_from_this<_Tp1>*, |
| const _Tp2*); |
| |
| template<_Lock_policy _Lp> |
| inline void |
| __enable_shared_from_this_helper(const __shared_count<_Lp>&, ...) |
| { } |
| |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_TR1 |
| struct __static_cast_tag { }; |
| struct __const_cast_tag { }; |
| struct __dynamic_cast_tag { }; |
| #endif |
| |
| /** |
| * @class shared_ptr <tr1/memory> |
| * |
| * A smart pointer with reference-counted copy semantics. |
| * The object pointed to is deleted when the last shared_ptr pointing to |
| * it is destroyed or reset. |
| */ |
| template<typename _Tp, _Lock_policy _Lp> |
| class __shared_ptr |
| { |
| public: |
| typedef _Tp element_type; |
| |
| /** @brief Construct an empty %__shared_ptr. |
| * @post use_count()==0 && get()==0 |
| */ |
| __shared_ptr() |
| : _M_ptr(0), _M_refcount() // never throws |
| { } |
| |
| /** @brief Construct a %__shared_ptr that owns the pointer @a __p. |
| * @param __p A pointer that is convertible to element_type*. |
| * @post use_count() == 1 && get() == __p |
| * @throw std::bad_alloc, in which case @c delete @a __p is called. |
| */ |
| template<typename _Tp1> |
| explicit |
| __shared_ptr(_Tp1* __p) |
| : _M_ptr(__p), _M_refcount(__p) |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| // __glibcxx_function_requires(_CompleteConcept<_Tp1*>) |
| __enable_shared_from_this_helper(_M_refcount, __p, __p); |
| } |
| |
| // |
| // Requirements: _Deleter's copy constructor and destructor must not throw |
| // |
| // __shared_ptr will release __p by calling __d(__p) |
| // |
| /** @brief Construct a %__shared_ptr that owns the pointer @a __p |
| * and the deleter @a __d. |
| * @param __p A pointer. |
| * @param __d A deleter. |
| * @post use_count() == 1 && get() == __p |
| * @throw std::bad_alloc, in which case @a __d(__p) is called. |
| */ |
| template<typename _Tp1, typename _Deleter> |
| __shared_ptr(_Tp1* __p, _Deleter __d) |
| : _M_ptr(__p), _M_refcount(__p, __d) |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| // TODO requires _Deleter CopyConstructible and __d(__p) well-formed |
| __enable_shared_from_this_helper(_M_refcount, __p, __p); |
| } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| // |
| // Requirements: _Deleter's copy constructor and destructor must not throw |
| // _Alloc's copy constructor and destructor must not throw. |
| // |
| // __shared_ptr will release __p by calling __d(__p) |
| // |
| /** @brief Construct a %__shared_ptr that owns the pointer @a __p |
| * and the deleter @a __d. |
| * @param __p A pointer. |
| * @param __d A deleter. |
| * @param __a An allocator. |
| * @post use_count() == 1 && get() == __p |
| * @throw std::bad_alloc, in which case @a __d(__p) is called. |
| */ |
| template<typename _Tp1, typename _Deleter, typename _Alloc> |
| __shared_ptr(_Tp1* __p, _Deleter __d, const _Alloc& __a) |
| : _M_ptr(__p), _M_refcount(__p, __d, __a) |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| // TODO requires _Deleter CopyConstructible and __d(__p) well-formed |
| __enable_shared_from_this_helper(_M_refcount, __p, __p); |
| } |
| |
| /** @brief Constructs a %__shared_ptr instance that stores @a __p |
| * and shares ownership with @a __r. |
| * @param __r A %__shared_ptr. |
| * @param __p A pointer that will remain valid while @a *__r is valid. |
| * @post get() == __p && use_count() == __r.use_count() |
| * |
| * This can be used to construct a @c shared_ptr to a sub-object |
| * of an object managed by an existing @c shared_ptr. |
| * |
| * @code |
| * shared_ptr< pair<int,int> > pii(new pair<int,int>()); |
| * shared_ptr<int> pi(pii, &pii->first); |
| * assert(pii.use_count() == 2); |
| * @endcode |
| */ |
| template<typename _Tp1> |
| __shared_ptr(const __shared_ptr<_Tp1, _Lp>& __r, _Tp* __p) |
| : _M_ptr(__p), _M_refcount(__r._M_refcount) // never throws |
| { } |
| #endif |
| |
| // generated copy constructor, assignment, destructor are fine. |
| |
| /** @brief If @a __r is empty, constructs an empty %__shared_ptr; |
| * otherwise construct a %__shared_ptr that shares ownership |
| * with @a __r. |
| * @param __r A %__shared_ptr. |
| * @post get() == __r.get() && use_count() == __r.use_count() |
| */ |
| template<typename _Tp1> |
| __shared_ptr(const __shared_ptr<_Tp1, _Lp>& __r) |
| : _M_ptr(__r._M_ptr), _M_refcount(__r._M_refcount) // never throws |
| { __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| /** @brief Move-constructs a %__shared_ptr instance from @a __r. |
| * @param __r A %__shared_ptr rvalue. |
| * @post *this contains the old value of @a __r, @a __r is empty. |
| */ |
| __shared_ptr(__shared_ptr&& __r) |
| : _M_ptr(__r._M_ptr), _M_refcount() // never throws |
| { |
| _M_refcount._M_swap(__r._M_refcount); |
| __r._M_ptr = 0; |
| } |
| |
| /** @brief Move-constructs a %__shared_ptr instance from @a __r. |
| * @param __r A %__shared_ptr rvalue. |
| * @post *this contains the old value of @a __r, @a __r is empty. |
| */ |
| template<typename _Tp1> |
| __shared_ptr(__shared_ptr<_Tp1, _Lp>&& __r) |
| : _M_ptr(__r._M_ptr), _M_refcount() // never throws |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| _M_refcount._M_swap(__r._M_refcount); |
| __r._M_ptr = 0; |
| } |
| #endif |
| |
| /** @brief Constructs a %__shared_ptr that shares ownership with @a __r |
| * and stores a copy of the pointer stored in @a __r. |
| * @param __r A weak_ptr. |
| * @post use_count() == __r.use_count() |
| * @throw bad_weak_ptr when __r.expired(), |
| * in which case the constructor has no effect. |
| */ |
| template<typename _Tp1> |
| explicit |
| __shared_ptr(const __weak_ptr<_Tp1, _Lp>& __r) |
| : _M_refcount(__r._M_refcount) // may throw |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| // It is now safe to copy __r._M_ptr, as _M_refcount(__r._M_refcount) |
| // did not throw. |
| _M_ptr = __r._M_ptr; |
| } |
| |
| /** |
| * @post use_count() == 1 and __r.get() == 0 |
| */ |
| #if !defined(__GXX_EXPERIMENTAL_CXX0X__) || _GLIBCXX_DEPRECATED |
| template<typename _Tp1> |
| explicit |
| __shared_ptr(std::auto_ptr<_Tp1>& __r) |
| : _M_ptr(__r.get()), _M_refcount() |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| // TODO requires _Tp1 is complete, delete __r.release() well-formed |
| _Tp1* __tmp = __r.get(); |
| _M_refcount = __shared_count<_Lp>(__r); |
| __enable_shared_from_this_helper(_M_refcount, __tmp, __tmp); |
| } |
| #endif |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_TR1 |
| template<typename _Tp1> |
| __shared_ptr(const __shared_ptr<_Tp1, _Lp>& __r, __static_cast_tag) |
| : _M_ptr(static_cast<element_type*>(__r._M_ptr)), |
| _M_refcount(__r._M_refcount) |
| { } |
| |
| template<typename _Tp1> |
| __shared_ptr(const __shared_ptr<_Tp1, _Lp>& __r, __const_cast_tag) |
| : _M_ptr(const_cast<element_type*>(__r._M_ptr)), |
| _M_refcount(__r._M_refcount) |
| { } |
| |
| template<typename _Tp1> |
| __shared_ptr(const __shared_ptr<_Tp1, _Lp>& __r, __dynamic_cast_tag) |
| : _M_ptr(dynamic_cast<element_type*>(__r._M_ptr)), |
| _M_refcount(__r._M_refcount) |
| { |
| if (_M_ptr == 0) // need to allocate new counter -- the cast failed |
| _M_refcount = __shared_count<_Lp>(); |
| } |
| #endif |
| |
| template<typename _Tp1> |
| __shared_ptr& |
| operator=(const __shared_ptr<_Tp1, _Lp>& __r) // never throws |
| { |
| _M_ptr = __r._M_ptr; |
| _M_refcount = __r._M_refcount; // __shared_count::op= doesn't throw |
| return *this; |
| } |
| |
| #if !defined(__GXX_EXPERIMENTAL_CXX0X__) || _GLIBCXX_DEPRECATED |
| template<typename _Tp1> |
| __shared_ptr& |
| operator=(std::auto_ptr<_Tp1>& __r) |
| { |
| __shared_ptr(__r).swap(*this); |
| return *this; |
| } |
| #endif |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| __shared_ptr& |
| operator=(__shared_ptr&& __r) |
| { |
| __shared_ptr(std::move(__r)).swap(*this); |
| return *this; |
| } |
| |
| template<class _Tp1> |
| __shared_ptr& |
| operator=(__shared_ptr<_Tp1, _Lp>&& __r) |
| { |
| __shared_ptr(std::move(__r)).swap(*this); |
| return *this; |
| } |
| #endif |
| |
| void |
| reset() // never throws |
| { __shared_ptr().swap(*this); } |
| |
| template<typename _Tp1> |
| void |
| reset(_Tp1* __p) // _Tp1 must be complete. |
| { |
| // Catch self-reset errors. |
| _GLIBCXX_DEBUG_ASSERT(__p == 0 || __p != _M_ptr); |
| __shared_ptr(__p).swap(*this); |
| } |
| |
| template<typename _Tp1, typename _Deleter> |
| void |
| reset(_Tp1* __p, _Deleter __d) |
| { __shared_ptr(__p, __d).swap(*this); } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| template<typename _Tp1, typename _Deleter, typename _Alloc> |
| void |
| reset(_Tp1* __p, _Deleter __d, const _Alloc& __a) |
| { __shared_ptr(__p, __d, __a).swap(*this); } |
| |
| // Allow class instantiation when _Tp is [cv-qual] void. |
| typename std::add_lvalue_reference<_Tp>::type |
| #else |
| // Allow class instantiation when _Tp is [cv-qual] void. |
| typename std::tr1::add_reference<_Tp>::type |
| #endif |
| operator*() const // never throws |
| { |
| _GLIBCXX_DEBUG_ASSERT(_M_ptr != 0); |
| return *_M_ptr; |
| } |
| |
| _Tp* |
| operator->() const // never throws |
| { |
| _GLIBCXX_DEBUG_ASSERT(_M_ptr != 0); |
| return _M_ptr; |
| } |
| |
| _Tp* |
| get() const // never throws |
| { return _M_ptr; } |
| |
| // Implicit conversion to "bool" |
| private: |
| typedef _Tp* __shared_ptr::*__unspecified_bool_type; |
| |
| public: |
| operator __unspecified_bool_type() const // never throws |
| { return _M_ptr == 0 ? 0 : &__shared_ptr::_M_ptr; } |
| |
| bool |
| unique() const // never throws |
| { return _M_refcount._M_unique(); } |
| |
| long |
| use_count() const // never throws |
| { return _M_refcount._M_get_use_count(); } |
| |
| void |
| swap(__shared_ptr<_Tp, _Lp>& __other) // never throws |
| { |
| std::swap(_M_ptr, __other._M_ptr); |
| _M_refcount._M_swap(__other._M_refcount); |
| } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| protected: |
| // This constructor is non-standard, it is used by allocate_shared. |
| template<typename _Alloc, typename... _Args> |
| __shared_ptr(_Sp_make_shared_tag __tag, _Alloc __a, _Args&&... __args) |
| : _M_ptr() |
| , _M_refcount(__tag, (_Tp*)0, __a, std::forward<_Args>(__args)...) |
| { |
| // _M_ptr needs to point to the newly constructed object. |
| // This relies on _Sp_counted_ptr_inplace::_M_get_deleter. |
| void * __p = _M_refcount._M_get_deleter(typeid(__tag)); |
| _M_ptr = static_cast<_Tp*>(__p); |
| } |
| |
| template<typename _Tp1, _Lock_policy _Lp1, typename _Alloc, |
| typename... _Args> |
| friend __shared_ptr<_Tp1, _Lp1> |
| __allocate_shared(_Alloc __a, _Args&&... __args); |
| #endif |
| |
| private: |
| void* |
| _M_get_deleter(const std::type_info& __ti) const |
| { return _M_refcount._M_get_deleter(__ti); } |
| |
| template<typename _Tp1, _Lock_policy _Lp1> |
| bool |
| _M_less(const __shared_ptr<_Tp1, _Lp1>& __rhs) const |
| { return _M_refcount < __rhs._M_refcount; } |
| |
| template<typename _Tp1, _Lock_policy _Lp1> friend class __shared_ptr; |
| template<typename _Tp1, _Lock_policy _Lp1> friend class __weak_ptr; |
| |
| template<typename _Del, typename _Tp1, _Lock_policy _Lp1> |
| friend _Del* get_deleter(const __shared_ptr<_Tp1, _Lp1>&); |
| |
| // Friends injected into enclosing namespace and found by ADL: |
| template<typename _Tp1> |
| friend inline bool |
| operator==(const __shared_ptr& __a, const __shared_ptr<_Tp1, _Lp>& __b) |
| { return __a.get() == __b.get(); } |
| |
| template<typename _Tp1> |
| friend inline bool |
| operator!=(const __shared_ptr& __a, const __shared_ptr<_Tp1, _Lp>& __b) |
| { return __a.get() != __b.get(); } |
| |
| template<typename _Tp1> |
| friend inline bool |
| operator<(const __shared_ptr& __a, const __shared_ptr<_Tp1, _Lp>& __b) |
| { return __a._M_less(__b); } |
| |
| _Tp* _M_ptr; // Contained pointer. |
| __shared_count<_Lp> _M_refcount; // Reference counter. |
| }; |
| |
| // 2.2.3.8 shared_ptr specialized algorithms. |
| template<typename _Tp, _Lock_policy _Lp> |
| inline void |
| swap(__shared_ptr<_Tp, _Lp>& __a, __shared_ptr<_Tp, _Lp>& __b) |
| { __a.swap(__b); } |
| |
| // 2.2.3.9 shared_ptr casts |
| /** @warning The seemingly equivalent |
| * <code>shared_ptr<_Tp, _Lp>(static_cast<_Tp*>(__r.get()))</code> |
| * will eventually result in undefined behaviour, |
| * attempting to delete the same object twice. |
| */ |
| template<typename _Tp, typename _Tp1, _Lock_policy _Lp> |
| inline __shared_ptr<_Tp, _Lp> |
| static_pointer_cast(const __shared_ptr<_Tp1, _Lp>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| return __shared_ptr<_Tp, _Lp>(__r, static_cast<_Tp*>(__r.get())); |
| #else |
| return __shared_ptr<_Tp, _Lp>(__r, __static_cast_tag()); |
| #endif |
| } |
| |
| /** @warning The seemingly equivalent |
| * <code>shared_ptr<_Tp, _Lp>(const_cast<_Tp*>(__r.get()))</code> |
| * will eventually result in undefined behaviour, |
| * attempting to delete the same object twice. |
| */ |
| template<typename _Tp, typename _Tp1, _Lock_policy _Lp> |
| inline __shared_ptr<_Tp, _Lp> |
| const_pointer_cast(const __shared_ptr<_Tp1, _Lp>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| return __shared_ptr<_Tp, _Lp>(__r, const_cast<_Tp*>(__r.get())); |
| #else |
| return __shared_ptr<_Tp, _Lp>(__r, __const_cast_tag()); |
| #endif |
| } |
| |
| /** @warning The seemingly equivalent |
| * <code>shared_ptr<_Tp, _Lp>(dynamic_cast<_Tp*>(__r.get()))</code> |
| * will eventually result in undefined behaviour, |
| * attempting to delete the same object twice. |
| */ |
| template<typename _Tp, typename _Tp1, _Lock_policy _Lp> |
| inline __shared_ptr<_Tp, _Lp> |
| dynamic_pointer_cast(const __shared_ptr<_Tp1, _Lp>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| if (_Tp* __p = dynamic_cast<_Tp*>(__r.get())) |
| return __shared_ptr<_Tp, _Lp>(__r, __p); |
| return __shared_ptr<_Tp, _Lp>(); |
| #else |
| return __shared_ptr<_Tp, _Lp>(__r, __dynamic_cast_tag()); |
| #endif |
| } |
| |
| // 2.2.3.7 shared_ptr I/O |
| template<typename _Ch, typename _Tr, typename _Tp, _Lock_policy _Lp> |
| std::basic_ostream<_Ch, _Tr>& |
| operator<<(std::basic_ostream<_Ch, _Tr>& __os, |
| const __shared_ptr<_Tp, _Lp>& __p) |
| { |
| __os << __p.get(); |
| return __os; |
| } |
| |
| // 2.2.3.10 shared_ptr get_deleter (experimental) |
| template<typename _Del, typename _Tp, _Lock_policy _Lp> |
| inline _Del* |
| get_deleter(const __shared_ptr<_Tp, _Lp>& __p) |
| { return static_cast<_Del*>(__p._M_get_deleter(typeid(_Del))); } |
| |
| |
| template<typename _Tp, _Lock_policy _Lp> |
| class __weak_ptr |
| { |
| public: |
| typedef _Tp element_type; |
| |
| __weak_ptr() |
| : _M_ptr(0), _M_refcount() // never throws |
| { } |
| |
| // Generated copy constructor, assignment, destructor are fine. |
| |
| // The "obvious" converting constructor implementation: |
| // |
| // template<typename _Tp1> |
| // __weak_ptr(const __weak_ptr<_Tp1, _Lp>& __r) |
| // : _M_ptr(__r._M_ptr), _M_refcount(__r._M_refcount) // never throws |
| // { } |
| // |
| // has a serious problem. |
| // |
| // __r._M_ptr may already have been invalidated. The _M_ptr(__r._M_ptr) |
| // conversion may require access to *__r._M_ptr (virtual inheritance). |
| // |
| // It is not possible to avoid spurious access violations since |
| // in multithreaded programs __r._M_ptr may be invalidated at any point. |
| template<typename _Tp1> |
| __weak_ptr(const __weak_ptr<_Tp1, _Lp>& __r) |
| : _M_refcount(__r._M_refcount) // never throws |
| { |
| __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) |
| _M_ptr = __r.lock().get(); |
| } |
| |
| template<typename _Tp1> |
| __weak_ptr(const __shared_ptr<_Tp1, _Lp>& __r) |
| : _M_ptr(__r._M_ptr), _M_refcount(__r._M_refcount) // never throws |
| { __glibcxx_function_requires(_ConvertibleConcept<_Tp1*, _Tp*>) } |
| |
| template<typename _Tp1> |
| __weak_ptr& |
| operator=(const __weak_ptr<_Tp1, _Lp>& __r) // never throws |
| { |
| _M_ptr = __r.lock().get(); |
| _M_refcount = __r._M_refcount; |
| return *this; |
| } |
| |
| template<typename _Tp1> |
| __weak_ptr& |
| operator=(const __shared_ptr<_Tp1, _Lp>& __r) // never throws |
| { |
| _M_ptr = __r._M_ptr; |
| _M_refcount = __r._M_refcount; |
| return *this; |
| } |
| |
| __shared_ptr<_Tp, _Lp> |
| lock() const // never throws |
| { |
| #ifdef __GTHREADS |
| // Optimization: avoid throw overhead. |
| if (expired()) |
| return __shared_ptr<element_type, _Lp>(); |
| |
| try |
| { |
| return __shared_ptr<element_type, _Lp>(*this); |
| } |
| catch(const bad_weak_ptr&) |
| { |
| // Q: How can we get here? |
| // A: Another thread may have invalidated r after the |
| // use_count test above. |
| return __shared_ptr<element_type, _Lp>(); |
| } |
| |
| #else |
| // Optimization: avoid try/catch overhead when single threaded. |
| return expired() ? __shared_ptr<element_type, _Lp>() |
| : __shared_ptr<element_type, _Lp>(*this); |
| |
| #endif |
| } // XXX MT |
| |
| long |
| use_count() const // never throws |
| { return _M_refcount._M_get_use_count(); } |
| |
| bool |
| expired() const // never throws |
| { return _M_refcount._M_get_use_count() == 0; } |
| |
| void |
| reset() // never throws |
| { __weak_ptr().swap(*this); } |
| |
| void |
| swap(__weak_ptr& __s) // never throws |
| { |
| std::swap(_M_ptr, __s._M_ptr); |
| _M_refcount._M_swap(__s._M_refcount); |
| } |
| |
| private: |
| // Used by __enable_shared_from_this. |
| void |
| _M_assign(_Tp* __ptr, const __shared_count<_Lp>& __refcount) |
| { |
| _M_ptr = __ptr; |
| _M_refcount = __refcount; |
| } |
| |
| template<typename _Tp1> |
| bool |
| _M_less(const __weak_ptr<_Tp1, _Lp>& __rhs) const |
| { return _M_refcount < __rhs._M_refcount; } |
| |
| template<typename _Tp1, _Lock_policy _Lp1> friend class __shared_ptr; |
| template<typename _Tp1, _Lock_policy _Lp1> friend class __weak_ptr; |
| friend class __enable_shared_from_this<_Tp, _Lp>; |
| friend class enable_shared_from_this<_Tp>; |
| |
| // Friend injected into namespace and found by ADL. |
| template<typename _Tp1> |
| friend inline bool |
| operator<(const __weak_ptr& __lhs, const __weak_ptr<_Tp1, _Lp>& __rhs) |
| { return __lhs._M_less(__rhs); } |
| |
| _Tp* _M_ptr; // Contained pointer. |
| __weak_count<_Lp> _M_refcount; // Reference counter. |
| }; |
| |
| // 2.2.4.7 weak_ptr specialized algorithms. |
| template<typename _Tp, _Lock_policy _Lp> |
| inline void |
| swap(__weak_ptr<_Tp, _Lp>& __a, __weak_ptr<_Tp, _Lp>& __b) |
| { __a.swap(__b); } |
| |
| |
| template<typename _Tp, _Lock_policy _Lp> |
| class __enable_shared_from_this |
| { |
| protected: |
| __enable_shared_from_this() { } |
| |
| __enable_shared_from_this(const __enable_shared_from_this&) { } |
| |
| __enable_shared_from_this& |
| operator=(const __enable_shared_from_this&) |
| { return *this; } |
| |
| ~__enable_shared_from_this() { } |
| |
| public: |
| __shared_ptr<_Tp, _Lp> |
| shared_from_this() |
| { return __shared_ptr<_Tp, _Lp>(this->_M_weak_this); } |
| |
| __shared_ptr<const _Tp, _Lp> |
| shared_from_this() const |
| { return __shared_ptr<const _Tp, _Lp>(this->_M_weak_this); } |
| |
| private: |
| template<typename _Tp1> |
| void |
| _M_weak_assign(_Tp1* __p, const __shared_count<_Lp>& __n) const |
| { _M_weak_this._M_assign(__p, __n); } |
| |
| template<typename _Tp1> |
| friend void |
| __enable_shared_from_this_helper(const __shared_count<_Lp>& __pn, |
| const __enable_shared_from_this* __pe, |
| const _Tp1* __px) |
| { |
| if (__pe != 0) |
| __pe->_M_weak_assign(const_cast<_Tp1*>(__px), __pn); |
| } |
| |
| mutable __weak_ptr<_Tp, _Lp> _M_weak_this; |
| }; |
| |
| |
| // The actual TR1 shared_ptr, with forwarding constructors and |
| // assignment operators. |
| template<typename _Tp> |
| class shared_ptr |
| : public __shared_ptr<_Tp> |
| { |
| public: |
| shared_ptr() |
| : __shared_ptr<_Tp>() { } |
| |
| template<typename _Tp1> |
| explicit |
| shared_ptr(_Tp1* __p) |
| : __shared_ptr<_Tp>(__p) { } |
| |
| template<typename _Tp1, typename _Deleter> |
| shared_ptr(_Tp1* __p, _Deleter __d) |
| : __shared_ptr<_Tp>(__p, __d) { } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| template<typename _Tp1, typename _Deleter, typename _Alloc> |
| shared_ptr(_Tp1* __p, _Deleter __d, const _Alloc& __a) |
| : __shared_ptr<_Tp>(__p, __d, __a) { } |
| |
| // Aliasing constructor |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r, _Tp* __p) |
| : __shared_ptr<_Tp>(__r, __p) { } |
| #endif |
| |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r) |
| : __shared_ptr<_Tp>(__r) { } |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| shared_ptr(shared_ptr&& __r) |
| : __shared_ptr<_Tp>(std::move(__r)) { } |
| |
| template<typename _Tp1> |
| shared_ptr(shared_ptr<_Tp1>&& __r) |
| : __shared_ptr<_Tp>(std::move(__r)) { } |
| #endif |
| |
| template<typename _Tp1> |
| explicit |
| shared_ptr(const weak_ptr<_Tp1>& __r) |
| : __shared_ptr<_Tp>(__r) { } |
| |
| #if !defined(__GXX_EXPERIMENTAL_CXX0X__) || _GLIBCXX_DEPRECATED |
| template<typename _Tp1> |
| explicit |
| shared_ptr(std::auto_ptr<_Tp1>& __r) |
| : __shared_ptr<_Tp>(__r) { } |
| #endif |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_TR1 |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r, __static_cast_tag) |
| : __shared_ptr<_Tp>(__r, __static_cast_tag()) { } |
| |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r, __const_cast_tag) |
| : __shared_ptr<_Tp>(__r, __const_cast_tag()) { } |
| |
| template<typename _Tp1> |
| shared_ptr(const shared_ptr<_Tp1>& __r, __dynamic_cast_tag) |
| : __shared_ptr<_Tp>(__r, __dynamic_cast_tag()) { } |
| #endif |
| |
| template<typename _Tp1> |
| shared_ptr& |
| operator=(const shared_ptr<_Tp1>& __r) // never throws |
| { |
| this->__shared_ptr<_Tp>::operator=(__r); |
| return *this; |
| } |
| |
| #if !defined(__GXX_EXPERIMENTAL_CXX0X__) || _GLIBCXX_DEPRECATED |
| template<typename _Tp1> |
| shared_ptr& |
| operator=(std::auto_ptr<_Tp1>& __r) |
| { |
| this->__shared_ptr<_Tp>::operator=(__r); |
| return *this; |
| } |
| #endif |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| shared_ptr& |
| operator=(shared_ptr&& __r) |
| { |
| this->__shared_ptr<_Tp>::operator=(std::move(__r)); |
| return *this; |
| } |
| |
| template<class _Tp1> |
| shared_ptr& |
| operator=(shared_ptr<_Tp1>&& __r) |
| { |
| this->__shared_ptr<_Tp>::operator=(std::move(__r)); |
| return *this; |
| } |
| #endif |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| private: |
| // This constructor is non-standard, it is used by allocate_shared. |
| template<typename _Alloc, typename... _Args> |
| shared_ptr(_Sp_make_shared_tag __tag, _Alloc __a, _Args&&... __args) |
| : __shared_ptr<_Tp>(__tag, __a, std::forward<_Args>(__args)...) |
| { } |
| |
| template<typename _Tp1, typename _Alloc, typename... _Args> |
| friend shared_ptr<_Tp1> |
| allocate_shared(_Alloc __a, _Args&&... __args); |
| #endif |
| }; |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| static_pointer_cast(const shared_ptr<_Tp1>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get())); |
| #else |
| return shared_ptr<_Tp>(__r, __static_cast_tag()); |
| #endif |
| } |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| const_pointer_cast(const shared_ptr<_Tp1>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| return shared_ptr<_Tp>(__r, const_cast<_Tp*>(__r.get())); |
| #else |
| return shared_ptr<_Tp>(__r, __const_cast_tag()); |
| #endif |
| } |
| |
| template<typename _Tp, typename _Tp1> |
| inline shared_ptr<_Tp> |
| dynamic_pointer_cast(const shared_ptr<_Tp1>& __r) |
| { |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| if (_Tp* __p = dynamic_cast<_Tp*>(__r.get())) |
| return shared_ptr<_Tp>(__r, __p); |
| return shared_ptr<_Tp>(); |
| #else |
| return shared_ptr<_Tp>(__r, __dynamic_cast_tag()); |
| #endif |
| } |
| |
| |
| // The actual TR1 weak_ptr, with forwarding constructors and |
| // assignment operators. |
| template<typename _Tp> |
| class weak_ptr |
| : public __weak_ptr<_Tp> |
| { |
| public: |
| weak_ptr() |
| : __weak_ptr<_Tp>() { } |
| |
| template<typename _Tp1> |
| weak_ptr(const weak_ptr<_Tp1>& __r) |
| : __weak_ptr<_Tp>(__r) { } |
| |
| template<typename _Tp1> |
| weak_ptr(const shared_ptr<_Tp1>& __r) |
| : __weak_ptr<_Tp>(__r) { } |
| |
| template<typename _Tp1> |
| weak_ptr& |
| operator=(const weak_ptr<_Tp1>& __r) // never throws |
| { |
| this->__weak_ptr<_Tp>::operator=(__r); |
| return *this; |
| } |
| |
| template<typename _Tp1> |
| weak_ptr& |
| operator=(const shared_ptr<_Tp1>& __r) // never throws |
| { |
| this->__weak_ptr<_Tp>::operator=(__r); |
| return *this; |
| } |
| |
| shared_ptr<_Tp> |
| lock() const // never throws |
| { |
| #ifdef __GTHREADS |
| if (this->expired()) |
| return shared_ptr<_Tp>(); |
| |
| try |
| { |
| return shared_ptr<_Tp>(*this); |
| } |
| catch(const bad_weak_ptr&) |
| { |
| return shared_ptr<_Tp>(); |
| } |
| #else |
| return this->expired() ? shared_ptr<_Tp>() |
| : shared_ptr<_Tp>(*this); |
| #endif |
| } |
| }; |
| |
| |
| template<typename _Tp> |
| class enable_shared_from_this |
| { |
| protected: |
| enable_shared_from_this() { } |
| |
| enable_shared_from_this(const enable_shared_from_this&) { } |
| |
| enable_shared_from_this& |
| operator=(const enable_shared_from_this&) |
| { return *this; } |
| |
| ~enable_shared_from_this() { } |
| |
| public: |
| shared_ptr<_Tp> |
| shared_from_this() |
| { return shared_ptr<_Tp>(this->_M_weak_this); } |
| |
| shared_ptr<const _Tp> |
| shared_from_this() const |
| { return shared_ptr<const _Tp>(this->_M_weak_this); } |
| |
| private: |
| template<typename _Tp1> |
| void |
| _M_weak_assign(_Tp1* __p, const __shared_count<>& __n) const |
| { _M_weak_this._M_assign(__p, __n); } |
| |
| template<typename _Tp1> |
| friend void |
| __enable_shared_from_this_helper(const __shared_count<>& __pn, |
| const enable_shared_from_this* __pe, |
| const _Tp1* __px) |
| { |
| if (__pe != 0) |
| __pe->_M_weak_assign(const_cast<_Tp1*>(__px), __pn); |
| } |
| |
| mutable weak_ptr<_Tp> _M_weak_this; |
| }; |
| |
| #ifdef _GLIBCXX_INCLUDE_AS_CXX0X |
| template<typename _Tp, _Lock_policy _Lp, typename _Alloc, typename... _Args> |
| inline __shared_ptr<_Tp, _Lp> |
| __allocate_shared(_Alloc __a, _Args&&... __args) |
| { |
| return __shared_ptr<_Tp, _Lp>(_Sp_make_shared_tag(), |
| std::forward<_Alloc>(__a), std::forward<_Args>(__args)...); |
| } |
| |
| template<typename _Tp, _Lock_policy _Lp, typename... _Args> |
| inline __shared_ptr<_Tp, _Lp> |
| __make_shared(_Args&&... __args) |
| { |
| typedef typename std::remove_const<_Tp>::type _Tp_nc; |
| return __allocate_shared<_Tp, _Lp>(std::allocator<_Tp_nc>(), |
| std::forward<_Args>(__args)...); |
| } |
| |
| /** @brief Create an object that is owned by a shared_ptr. |
| * @param __a An allocator. |
| * @param __args Arguments for the @a _Tp object's constructor. |
| * @return A shared_ptr that owns the newly created object. |
| * @throw An exception thrown from @a _Alloc::allocate or from the |
| * constructor of @a _Tp. |
| * |
| * A copy of @a __a will be used to allocate memory for the shared_ptr |
| * and the new object. |
| */ |
| template<typename _Tp, typename _Alloc, typename... _Args> |
| inline shared_ptr<_Tp> |
| allocate_shared(_Alloc __a, _Args&&... __args) |
| { |
| return shared_ptr<_Tp>(_Sp_make_shared_tag(), std::forward<_Alloc>(__a), |
| std::forward<_Args>(__args)...); |
| } |
| |
| /** @brief Create an object that is owned by a shared_ptr. |
| * @param __args Arguments for the @a _Tp object's constructor. |
| * @return A shared_ptr that owns the newly created object. |
| * @throw std::bad_alloc, or an exception thrown from the |
| * constructor of @a _Tp. |
| */ |
| template<typename _Tp, typename... _Args> |
| inline shared_ptr<_Tp> |
| make_shared(_Args&&... __args) |
| { |
| typedef typename std::remove_const<_Tp>::type _Tp_nc; |
| return allocate_shared<_Tp>(std::allocator<_Tp_nc>(), |
| std::forward<_Args>(__args)...); |
| } |
| #endif |
| |
| _GLIBCXX_END_NAMESPACE_TR1 |
| } |
