Edit File: unique_ptr.h
// unique_ptr implementation -*- C++ -*- // Copyright (C) 2008-2013 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 3, 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. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. /** @file bits/unique_ptr.h * This is an internal header file, included by other library headers. * Do not attempt to use it directly. @headername{memory} */ #ifndef _UNIQUE_PTR_H #define _UNIQUE_PTR_H 1 #include <bits/c++config.h> #include <debug/debug.h> #include <type_traits> #include <utility> #include <tuple> namespace std _GLIBCXX_VISIBILITY(default) { _GLIBCXX_BEGIN_NAMESPACE_VERSION /** * @addtogroup pointer_abstractions * @{ */ #if _GLIBCXX_USE_DEPRECATED template<typename> class auto_ptr; #endif /// Primary template, default_delete. template<typename _Tp> struct default_delete { constexpr default_delete() noexcept = default; template<typename _Up, typename = typename enable_if<is_convertible<_Up*, _Tp*>::value>::type> default_delete(const default_delete<_Up>&) noexcept { } void operator()(_Tp* __ptr) const { static_assert(sizeof(_Tp)>0, "can't delete pointer to incomplete type"); delete __ptr; } }; // _GLIBCXX_RESOLVE_LIB_DEFECTS // DR 740 - omit specialization for array objects with a compile time length /// Specialization, default_delete. template<typename _Tp> struct default_delete<_Tp[]> { private: template<typename _Up> using __remove_cv = typename remove_cv<_Up>::type; // Like is_base_of<_Tp, _Up> but false if unqualified types are the same template<typename _Up> using __is_derived_Tp = __and_< is_base_of<_Tp, _Up>, __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >; public: constexpr default_delete() noexcept = default; template<typename _Up, typename = typename enable_if<!__is_derived_Tp<_Up>::value>::type> default_delete(const default_delete<_Up[]>&) noexcept { } void operator()(_Tp* __ptr) const { static_assert(sizeof(_Tp)>0, "can't delete pointer to incomplete type"); delete [] __ptr; } template<typename _Up> typename enable_if<__is_derived_Tp<_Up>::value>::type operator()(_Up*) const = delete; }; /// 20.7.1.2 unique_ptr for single objects. template <typename _Tp, typename _Dp = default_delete<_Tp> > class unique_ptr { // use SFINAE to determine whether _Del::pointer exists class _Pointer { template<typename _Up> static typename _Up::pointer __test(typename _Up::pointer*); template<typename _Up> static _Tp* __test(...); typedef typename remove_reference<_Dp>::type _Del; public: typedef decltype(__test<_Del>(0)) type; }; typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type; __tuple_type _M_t; public: typedef typename _Pointer::type pointer; typedef _Tp element_type; typedef _Dp deleter_type; // Constructors. constexpr unique_ptr() noexcept : _M_t() { static_assert(!is_pointer<deleter_type>::value, "constructed with null function pointer deleter"); } explicit unique_ptr(pointer __p) noexcept : _M_t(__p, deleter_type()) { static_assert(!is_pointer<deleter_type>::value, "constructed with null function pointer deleter"); } unique_ptr(pointer __p, typename conditional<is_reference<deleter_type>::value, deleter_type, const deleter_type&>::type __d) noexcept : _M_t(__p, __d) { } unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d) noexcept : _M_t(std::move(__p), std::move(__d)) { static_assert(!std::is_reference<deleter_type>::value, "rvalue deleter bound to reference"); } constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { } // Move constructors. unique_ptr(unique_ptr&& __u) noexcept : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { } template<typename _Up, typename _Ep, typename = _Require< is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>, __not_<is_array<_Up>>, typename conditional<is_reference<_Dp>::value, is_same<_Ep, _Dp>, is_convertible<_Ep, _Dp>>::type>> unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter())) { } #if _GLIBCXX_USE_DEPRECATED template<typename _Up, typename = _Require< is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>> unique_ptr(auto_ptr<_Up>&& __u) noexcept; #endif // Destructor. ~unique_ptr() noexcept { auto& __ptr = std::get<0>(_M_t); if (__ptr != nullptr) get_deleter()(__ptr); __ptr = pointer(); } // Assignment. unique_ptr& operator=(unique_ptr&& __u) noexcept { reset(__u.release()); get_deleter() = std::forward<deleter_type>(__u.get_deleter()); return *this; } template<typename _Up, typename _Ep> typename enable_if< __and_< is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>, __not_<is_array<_Up>> >::value, unique_ptr&>::type operator=(unique_ptr<_Up, _Ep>&& __u) noexcept { reset(__u.release()); get_deleter() = std::forward<_Ep>(__u.get_deleter()); return *this; } unique_ptr& operator=(nullptr_t) noexcept { reset(); return *this; } // Observers. typename add_lvalue_reference<element_type>::type operator*() const { _GLIBCXX_DEBUG_ASSERT(get() != pointer()); return *get(); } pointer operator->() const noexcept { _GLIBCXX_DEBUG_ASSERT(get() != pointer()); return get(); } pointer get() const noexcept { return std::get<0>(_M_t); } deleter_type& get_deleter() noexcept { return std::get<1>(_M_t); } const deleter_type& get_deleter() const noexcept { return std::get<1>(_M_t); } explicit operator bool() const noexcept { return get() == pointer() ? false : true; } // Modifiers. pointer release() noexcept { pointer __p = get(); std::get<0>(_M_t) = pointer(); return __p; } void reset(pointer __p = pointer()) noexcept { using std::swap; swap(std::get<0>(_M_t), __p); if (__p != pointer()) get_deleter()(__p); } void swap(unique_ptr& __u) noexcept { using std::swap; swap(_M_t, __u._M_t); } // Disable copy from lvalue. unique_ptr(const unique_ptr&) = delete; unique_ptr& operator=(const unique_ptr&) = delete; }; /// 20.7.1.3 unique_ptr for array objects with a runtime length // [unique.ptr.runtime] // _GLIBCXX_RESOLVE_LIB_DEFECTS // DR 740 - omit specialization for array objects with a compile time length template<typename _Tp, typename _Dp> class unique_ptr<_Tp[], _Dp> { // use SFINAE to determine whether _Del::pointer exists class _Pointer { template<typename _Up> static typename _Up::pointer __test(typename _Up::pointer*); template<typename _Up> static _Tp* __test(...); typedef typename remove_reference<_Dp>::type _Del; public: typedef decltype(__test<_Del>(0)) type; }; typedef std::tuple<typename _Pointer::type, _Dp> __tuple_type; __tuple_type _M_t; template<typename _Up> using __remove_cv = typename remove_cv<_Up>::type; // like is_base_of<_Tp, _Up> but false if unqualified types are the same template<typename _Up> using __is_derived_Tp = __and_< is_base_of<_Tp, _Up>, __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >; template<typename _Up, typename _Ep, typename _Tp_pointer = typename _Pointer::type, typename _Up_pointer = typename unique_ptr<_Up, _Ep>::pointer> using __safe_conversion = __and_< is_convertible<_Up_pointer, _Tp_pointer>, is_array<_Up>, __or_<__not_<is_pointer<_Up_pointer>>, __not_<is_pointer<_Tp_pointer>>, __not_<__is_derived_Tp<typename remove_extent<_Up>::type>> > >; public: typedef typename _Pointer::type pointer; typedef _Tp element_type; typedef _Dp deleter_type; // Constructors. constexpr unique_ptr() noexcept : _M_t() { static_assert(!std::is_pointer<deleter_type>::value, "constructed with null function pointer deleter"); } explicit unique_ptr(pointer __p) noexcept : _M_t(__p, deleter_type()) { static_assert(!is_pointer<deleter_type>::value, "constructed with null function pointer deleter"); } template<typename _Up, typename = _Require<is_pointer<pointer>, is_convertible<_Up*, pointer>, __is_derived_Tp<_Up>>> explicit unique_ptr(_Up* __p) = delete; unique_ptr(pointer __p, typename conditional<is_reference<deleter_type>::value, deleter_type, const deleter_type&>::type __d) noexcept : _M_t(__p, __d) { } unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d) noexcept : _M_t(std::move(__p), std::move(__d)) { static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference"); } // Move constructor. unique_ptr(unique_ptr&& __u) noexcept : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { } constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { } template<typename _Up, typename _Ep, typename = _Require<__safe_conversion<_Up, _Ep>, typename conditional<is_reference<_Dp>::value, is_same<_Ep, _Dp>, is_convertible<_Ep, _Dp>>::type >> unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept : _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter())) { } // Destructor. ~unique_ptr() { auto& __ptr = std::get<0>(_M_t); if (__ptr != nullptr) get_deleter()(__ptr); __ptr = pointer(); } // Assignment. unique_ptr& operator=(unique_ptr&& __u) noexcept { reset(__u.release()); get_deleter() = std::forward<deleter_type>(__u.get_deleter()); return *this; } template<typename _Up, typename _Ep> typename enable_if<__safe_conversion<_Up, _Ep>::value, unique_ptr&>::type operator=(unique_ptr<_Up, _Ep>&& __u) noexcept { reset(__u.release()); get_deleter() = std::forward<_Ep>(__u.get_deleter()); return *this; } unique_ptr& operator=(nullptr_t) noexcept { reset(); return *this; } // Observers. typename std::add_lvalue_reference<element_type>::type operator[](size_t __i) const { _GLIBCXX_DEBUG_ASSERT(get() != pointer()); return get()[__i]; } pointer get() const noexcept { return std::get<0>(_M_t); } deleter_type& get_deleter() noexcept { return std::get<1>(_M_t); } const deleter_type& get_deleter() const noexcept { return std::get<1>(_M_t); } explicit operator bool() const noexcept { return get() == pointer() ? false : true; } // Modifiers. pointer release() noexcept { pointer __p = get(); std::get<0>(_M_t) = pointer(); return __p; } void reset() noexcept { reset(pointer()); } void reset(pointer __p) noexcept { using std::swap; swap(std::get<0>(_M_t), __p); if (__p != nullptr) get_deleter()(__p); } template<typename _Up, typename = _Require<is_pointer<pointer>, is_convertible<_Up*, pointer>, __is_derived_Tp<_Up>>> void reset(_Up*) = delete; void swap(unique_ptr& __u) noexcept { using std::swap; swap(_M_t, __u._M_t); } // Disable copy from lvalue. unique_ptr(const unique_ptr&) = delete; unique_ptr& operator=(const unique_ptr&) = delete; // Disable construction from convertible pointer types. template<typename _Up, typename = _Require<is_pointer<pointer>, is_convertible<_Up*, pointer>, __is_derived_Tp<_Up>>> unique_ptr(_Up*, typename conditional<is_reference<deleter_type>::value, deleter_type, const deleter_type&>::type) = delete; template<typename _Up, typename = _Require<is_pointer<pointer>, is_convertible<_Up*, pointer>, __is_derived_Tp<_Up>>> unique_ptr(_Up*, typename remove_reference<deleter_type>::type&&) = delete; }; template<typename _Tp, typename _Dp> inline void swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) noexcept { __x.swap(__y); } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator==(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { return __x.get() == __y.get(); } template<typename _Tp, typename _Dp> inline bool operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept { return !__x; } template<typename _Tp, typename _Dp> inline bool operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept { return !__x; } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator!=(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { return __x.get() != __y.get(); } template<typename _Tp, typename _Dp> inline bool operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept { return (bool)__x; } template<typename _Tp, typename _Dp> inline bool operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept { return (bool)__x; } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator<(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { typedef typename std::common_type<typename unique_ptr<_Tp, _Dp>::pointer, typename unique_ptr<_Up, _Ep>::pointer>::type _CT; return std::less<_CT>()(__x.get(), __y.get()); } template<typename _Tp, typename _Dp> inline bool operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(), nullptr); } template<typename _Tp, typename _Dp> inline bool operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr, __x.get()); } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator<=(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { return !(__y < __x); } template<typename _Tp, typename _Dp> inline bool operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) { return !(nullptr < __x); } template<typename _Tp, typename _Dp> inline bool operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) { return !(__x < nullptr); } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator>(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { return (__y < __x); } template<typename _Tp, typename _Dp> inline bool operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr, __x.get()); } template<typename _Tp, typename _Dp> inline bool operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(), nullptr); } template<typename _Tp, typename _Dp, typename _Up, typename _Ep> inline bool operator>=(const unique_ptr<_Tp, _Dp>& __x, const unique_ptr<_Up, _Ep>& __y) { return !(__x < __y); } template<typename _Tp, typename _Dp> inline bool operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) { return !(__x < nullptr); } template<typename _Tp, typename _Dp> inline bool operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) { return !(nullptr < __x); } /// std::hash specialization for unique_ptr. template<typename _Tp, typename _Dp> struct hash<unique_ptr<_Tp, _Dp>> : public __hash_base<size_t, unique_ptr<_Tp, _Dp>> { size_t operator()(const unique_ptr<_Tp, _Dp>& __u) const noexcept { typedef unique_ptr<_Tp, _Dp> _UP; return std::hash<typename _UP::pointer>()(__u.get()); } }; // @} group pointer_abstractions _GLIBCXX_END_NAMESPACE_VERSION } // namespace #endif /* _UNIQUE_PTR_H */