// unique_ptr implementation -*- C++ -*-
// Copyright (C) 2008, 2009, 2010, 2011 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
* @{
*/
/// Primary template, default_delete.
template<typename _Tp>
struct default_delete
{
constexpr default_delete() = default;
template<typename _Up, typename = typename
std::enable_if<std::is_convertible<_Up*, _Tp*>::value>::type>
default_delete(const default_delete<_Up>&) { }
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[]>
{
constexpr default_delete() = default;
void
operator()(_Tp* __ptr) const
{
static_assert(sizeof(_Tp)>0,
"can't delete pointer to incomplete type");
delete [] __ptr;
}
template<typename _Up> void operator()(_Up*) const = delete;
};
/// 20.7.12.2 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()
: _M_t()
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
explicit
unique_ptr(pointer __p)
: _M_t(__p, deleter_type())
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
unique_ptr(pointer __p,
typename std::conditional<std::is_reference<deleter_type>::value,
deleter_type, const deleter_type&>::type __d)
: _M_t(__p, __d) { }
unique_ptr(pointer __p,
typename std::remove_reference<deleter_type>::type&& __d)
: _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)
: _M_t()
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
// Move constructors.
unique_ptr(unique_ptr&& __u)
: _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
template<typename _Up, typename _Ep, typename = typename
std::enable_if
<std::is_convertible<typename unique_ptr<_Up, _Ep>::pointer,
pointer>::value
&& !std::is_array<_Up>::value
&& ((std::is_reference<_Dp>::value
&& std::is_same<_Ep, _Dp>::value)
|| (!std::is_reference<_Dp>::value
&& std::is_convertible<_Ep, _Dp>::value))>
::type>
unique_ptr(unique_ptr<_Up, _Ep>&& __u)
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }
#if _GLIBCXX_USE_DEPRECATED
template<typename _Up, typename = typename
std::enable_if<std::is_convertible<_Up*, _Tp*>::value
&& std::is_same<_Dp,
default_delete<_Tp>>::value>::type>
unique_ptr(auto_ptr<_Up>&& __u)
: _M_t(__u.release(), deleter_type()) { }
#endif
// Destructor.
~unique_ptr() { reset(); }
// Assignment.
unique_ptr&
operator=(unique_ptr&& __u)
{
reset(__u.release());
get_deleter() = std::forward<deleter_type>(__u.get_deleter());
return *this;
}
template<typename _Up, typename _Ep, typename = typename
std::enable_if
<std::is_convertible<typename unique_ptr<_Up, _Ep>::pointer,
pointer>::value
&& !std::is_array<_Up>::value>::type>
unique_ptr&
operator=(unique_ptr<_Up, _Ep>&& __u)
{
reset(__u.release());
get_deleter() = std::forward<_Ep>(__u.get_deleter());
return *this;
}
unique_ptr&
operator=(nullptr_t)
{
reset();
return *this;
}
// Observers.
typename std::add_lvalue_reference<element_type>::type
operator*() const
{
_GLIBCXX_DEBUG_ASSERT(get() != pointer());
return *get();
}
pointer
operator->() const
{
_GLIBCXX_DEBUG_ASSERT(get() != pointer());
return get();
}
pointer
get() const
{ return std::get<0>(_M_t); }
deleter_type&
get_deleter()
{ return std::get<1>(_M_t); }
const deleter_type&
get_deleter() const
{ return std::get<1>(_M_t); }
explicit operator bool() const
{ return get() == pointer() ? false : true; }
// Modifiers.
pointer
release()
{
pointer __p = get();
std::get<0>(_M_t) = pointer();
return __p;
}
void
reset(pointer __p = pointer())
{
using std::swap;
swap(std::get<0>(_M_t), __p);
if (__p != pointer())
get_deleter()(__p);
}
void
swap(unique_ptr& __u)
{
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;
};
/// 20.7.12.3 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>
{
typedef std::tuple<_Tp*, _Dp> __tuple_type;
__tuple_type _M_t;
public:
typedef _Tp* pointer;
typedef _Tp element_type;
typedef _Dp deleter_type;
// Constructors.
constexpr unique_ptr()
: _M_t()
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
explicit
unique_ptr(pointer __p)
: _M_t(__p, deleter_type())
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
unique_ptr(pointer __p,
typename std::conditional<std::is_reference<deleter_type>::value,
deleter_type, const deleter_type&>::type __d)
: _M_t(__p, __d) { }
unique_ptr(pointer __p,
typename std::remove_reference<deleter_type>::type && __d)
: _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)
: _M_t()
{ static_assert(!std::is_pointer<deleter_type>::value,
"constructed with null function pointer deleter"); }
// Move constructors.
unique_ptr(unique_ptr&& __u)
: _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }
template<typename _Up, typename _Ep>
unique_ptr(unique_ptr<_Up, _Ep>&& __u)
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }
// Destructor.
~unique_ptr() { reset(); }
// Assignment.
unique_ptr&
operator=(unique_ptr&& __u)
{
reset(__u.release());
get_deleter() = std::forward<deleter_type>(__u.get_deleter());
return *this;
}
template<typename _Up, typename _Ep>
unique_ptr&
operator=(unique_ptr<_Up, _Ep>&& __u)
{
reset(__u.release());
get_deleter() = std::forward<_Ep>(__u.get_deleter());
return *this;
}
unique_ptr&
operator=(nullptr_t)
{
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
{ return std::get<0>(_M_t); }
deleter_type&
get_deleter()
{ return std::get<1>(_M_t); }
const deleter_type&
get_deleter() const
{ return std::get<1>(_M_t); }
explicit operator bool() const
{ return get() == pointer() ? false : true; }
// Modifiers.
pointer
release()
{
pointer __p = get();
std::get<0>(_M_t) = pointer();
return __p;
}
void
reset(pointer __p = pointer())
{
using std::swap;
swap(std::get<0>(_M_t), __p);
if (__p != nullptr)
get_deleter()(__p);
}
void
reset(nullptr_t)
{
pointer __p = get();
std::get<0>(_M_t) = pointer();
if (__p != nullptr)
get_deleter()(__p);
}
// DR 821.
template<typename _Up>
void reset(_Up) = delete;
void
swap(unique_ptr& __u)
{
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.
// (N2315 - 20.6.5.3.1)
template<typename _Up>
unique_ptr(_Up*, typename
std::conditional<std::is_reference<deleter_type>::value,
deleter_type, const deleter_type&>::type,
typename std::enable_if<std::is_convertible<_Up*,
pointer>::value>::type* = 0) = delete;
template<typename _Up>
unique_ptr(_Up*, typename std::remove_reference<deleter_type>::type&&,
typename std::enable_if<std::is_convertible<_Up*,
pointer>::value>::type* = 0) = delete;
template<typename _Up>
explicit
unique_ptr(_Up*, typename std::enable_if<std::is_convertible<_Up*,
pointer>::value>::type* = 0) = delete;
};
template<typename _Tp, typename _Dp>
inline void
swap(unique_ptr<_Tp, _Dp>& __x,
unique_ptr<_Tp, _Dp>& __y)
{ __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)
{ return __x.get() == nullptr; }
template<typename _Tp, typename _Dp>
inline bool
operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __y)
{ return nullptr == __y.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 !(__x.get() == __y.get()); }
template<typename _Tp, typename _Dp>
inline bool
operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
{ return __x.get() != nullptr; }
template<typename _Tp, typename _Dp>
inline bool
operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __y)
{ return nullptr != __y.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 __x.get() < __y.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.get() < __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.get() < __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 !(__x.get() < __y.get()); }
/// std::hash specialization for unique_ptr.
template<typename _Tp, typename _Dp>
struct hash<unique_ptr<_Tp, _Dp>>
: public std::unary_function<unique_ptr<_Tp, _Dp>, size_t>
{
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 */