boost/interprocess/smart_ptr/unique_ptr.hpp
//////////////////////////////////////////////////////////////////////////////
// I, Howard Hinnant, hereby place this code in the public domain.
//////////////////////////////////////////////////////////////////////////////
//
// This file is the adaptation for Interprocess of
// Howard Hinnant's unique_ptr emulation code.
//
// (C) Copyright Ion Gaztanaga 2006-2012. 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/interprocess for documentation.
//
//////////////////////////////////////////////////////////////////////////////
#ifndef BOOST_INTERPROCESS_UNIQUE_PTR_HPP_INCLUDED
#define BOOST_INTERPROCESS_UNIQUE_PTR_HPP_INCLUDED
#include <boost/interprocess/detail/config_begin.hpp>
#include <boost/interprocess/detail/workaround.hpp>
#include <boost/assert.hpp>
#include <boost/interprocess/detail/utilities.hpp>
#include <boost/interprocess/detail/pointer_type.hpp>
#include <boost/move/move.hpp>
#include <boost/compressed_pair.hpp>
#include <boost/static_assert.hpp>
#include <boost/interprocess/detail/mpl.hpp>
#include <boost/interprocess/detail/type_traits.hpp>
#include <boost/interprocess/smart_ptr/deleter.hpp>
#include <cstddef>
//!\file
//!Describes the smart pointer unique_ptr
namespace boost{
namespace interprocess{
/// @cond
template <class T, class D> class unique_ptr;
namespace ipcdetail {
template <class T> struct unique_ptr_error;
template <class T, class D>
struct unique_ptr_error<const unique_ptr<T, D> >
{
typedef unique_ptr<T, D> type;
};
} //namespace ipcdetail {
/// @endcond
//!Template unique_ptr stores a pointer to an object and deletes that object
//!using the associated deleter when it is itself destroyed (such as when
//!leaving block scope.
//!
//!The unique_ptr provides a semantics of strict ownership. A unique_ptr owns the
//!object it holds a pointer to.
//!
//!A unique_ptr is not CopyConstructible, nor CopyAssignable, however it is
//!MoveConstructible and Move-Assignable.
//!
//!The uses of unique_ptr include providing exception safety for dynamically
//!allocated memory, passing ownership of dynamically allocated memory to a
//!function, and returning dynamically allocated memory from a function
//!
//!A client-supplied template argument D must be a
//!function pointer or functor for which, given a value d of type D and a pointer
//!ptr to a type T*, the expression d(ptr) is
//!valid and has the effect of deallocating the pointer as appropriate for that
//!deleter. D may also be an lvalue-reference to a deleter.
//!
//!If the deleter D maintains state, it is intended that this state stay with
//!the associated pointer as ownership is transferred
//!from unique_ptr to unique_ptr. The deleter state need never be copied,
//!only moved or swapped as pointer ownership
//!is moved around. That is, the deleter need only be MoveConstructible,
//!MoveAssignable, and Swappable, and need not be CopyConstructible
//!(unless copied into the unique_ptr) nor CopyAssignable.
template <class T, class D>
class unique_ptr
{
/// @cond
struct nat {int for_bool;};
struct nat2 {int for_nullptr;};
typedef int nat2::*nullptr_t;
typedef typename ipcdetail::add_reference<D>::type deleter_reference;
typedef typename ipcdetail::add_reference<const D>::type deleter_const_reference;
/// @endcond
public:
typedef T element_type;
typedef D deleter_type;
typedef typename ipcdetail::pointer_type<T, D>::type pointer;
//!Requires: D must be default constructible, and that construction must not
//!throw an exception. D must not be a reference type.
//!
//!Effects: Constructs a unique_ptr which owns nothing.
//!
//!Postconditions: get() == 0. get_deleter() returns a reference to a
//!default constructed deleter D.
//!
//!Throws: nothing.
unique_ptr()
: ptr_(pointer(0))
{}
//!Requires: The expression D()(p) must be well formed. The default constructor
//!of D must not throw an exception.
//!
//!D must not be a reference type.
//!
//!Effects: Constructs a unique_ptr which owns p.
//!
//!Postconditions: get() == p. get_deleter() returns a reference to a default constructed deleter D.
//!
//!Throws: nothing.
explicit unique_ptr(pointer p)
: ptr_(p)
{}
//!Requires: The expression d(p) must be well formed.
//!
//!Postconditions: get() == p. get_deleter() returns a reference to the
//!internally stored deleter. If D is a
//!reference type then get_deleter() returns a reference to the lvalue d.
//!
//!Throws: nothing.
unique_ptr(pointer p
,typename ipcdetail::if_<ipcdetail::is_reference<D>
,D
,typename ipcdetail::add_reference<const D>::type>::type d)
: ptr_(p, d)
{}
//!Requires: If the deleter is not a reference type, construction of the
//!deleter D from an lvalue D must not throw an exception.
//!
//!Effects: Constructs a unique_ptr which owns the pointer which u owns
//!(if any). If the deleter is not a reference type, it is move constructed
//!from u's deleter, otherwise the reference is copy constructed from u's deleter.
//!
//!After the construction, u no longer owns a pointer.
//![ Note: The deleter constructor can be implemented with
//! boost::forward<D>. -end note ]
//!
//!Postconditions: get() == value u.get() had before the construction.
//!get_deleter() returns a reference to the internally stored deleter which
//!was constructed from u.get_deleter(). If D is a reference type then get_-
//!deleter() and u.get_deleter() both reference the same lvalue deleter.
//!
//!Throws: nothing.
unique_ptr(BOOST_RV_REF(unique_ptr) u)
: ptr_(u.release(), boost::forward<D>(u.get_deleter()))
{}
//!Requires: If D is not a reference type, construction of the deleter
//!D from an rvalue of type E must be well formed
//!and not throw an exception. If D is a reference type, then E must be
//!the same type as D (diagnostic required). unique_ptr<U, E>::pointer
//!must be implicitly convertible to pointer.
//!
//!Effects: Constructs a unique_ptr which owns the pointer which u owns
//!(if any). If the deleter is not a reference
//!type, it is move constructed from u's deleter, otherwise the reference
//!is copy constructed from u's deleter.
//!
//!After the construction, u no longer owns a pointer.
//!
//!postconditions get() == value u.get() had before the construction,
//!modulo any required offset adjustments
//!resulting from the cast from U* to T*. get_deleter() returns a reference to the internally stored deleter which
//!was constructed from u.get_deleter().
//!
//!Throws: nothing.
template <class U, class E>
unique_ptr(BOOST_RV_REF_BEG unique_ptr<U, E> BOOST_RV_REF_END u,
typename ipcdetail::enable_if_c<
ipcdetail::is_convertible<typename unique_ptr<U, E>::pointer, pointer>::value &&
ipcdetail::is_convertible<E, D>::value &&
(
!ipcdetail::is_reference<D>::value ||
ipcdetail::is_same<D, E>::value
)
,
nat
>::type = nat())
: ptr_(const_cast<unique_ptr<U,E>&>(u).release(), boost::move<D>(u.get_deleter()))
{}
//!Effects: If get() == 0 there are no effects. Otherwise get_deleter()(get()).
//!
//!Throws: nothing.
~unique_ptr()
{ reset(); }
// assignment
//!Requires: Assignment of the deleter D from an rvalue D must not throw an exception.
//!
//!Effects: reset(u.release()) followed by a move assignment from u's deleter to
//!this deleter.
//!
//!Postconditions: This unique_ptr now owns the pointer which u owned, and u no
//!longer owns it.
//!
//!Returns: *this.
//!
//!Throws: nothing.
unique_ptr& operator=(BOOST_RV_REF(unique_ptr) u)
{
reset(u.release());
ptr_.second() = boost::move(u.get_deleter());
return *this;
}
//!Requires: Assignment of the deleter D from an rvalue D must not
//!throw an exception. U* must be implicitly convertible to T*.
//!
//!Effects: reset(u.release()) followed by a move assignment from
//!u's deleter to this deleter. If either D or E is
//!a reference type, then the referenced lvalue deleter participates
//!in the move assignment.
//!
//!Postconditions: This unique_ptr now owns the pointer which u owned,
//!and u no longer owns it.
//!
//!Returns: *this.
//!
//!Throws: nothing.
template <class U, class E>
unique_ptr& operator=(BOOST_RV_REF_BEG unique_ptr<U, E> BOOST_RV_REF_END u)
{
reset(u.release());
ptr_.second() = boost::move(u.get_deleter());
return *this;
}
//!Assigns from the literal 0 or NULL.
//!
//!Effects: reset().
//!
//!Postcondition: get() == 0
//!
//!Returns: *this.
//!
//!Throws: nothing.
unique_ptr& operator=(nullptr_t)
{
reset();
return *this;
}
//!Requires: get() != 0.
//!Returns: *get().
//!Throws: nothing.
typename ipcdetail::add_reference<T>::type operator*() const
{ return *ptr_.first(); }
//!Requires: get() != 0.
//!Returns: get().
//!Throws: nothing.
pointer operator->() const
{ return ptr_.first(); }
//!Returns: The stored pointer.
//!Throws: nothing.
pointer get() const
{ return ptr_.first(); }
//!Returns: A reference to the stored deleter.
//!
//!Throws: nothing.
deleter_reference get_deleter()
{ return ptr_.second(); }
//!Returns: A const reference to the stored deleter.
//!
//!Throws: nothing.
deleter_const_reference get_deleter() const
{ return ptr_.second(); }
//!Returns: An unspecified value that, when used in boolean
//!contexts, is equivalent to get() != 0.
//!
//!Throws: nothing.
operator int nat::*() const
{ return ptr_.first() ? &nat::for_bool : 0; }
//!Postcondition: get() == 0.
//!
//!Returns: The value get() had at the start of the call to release.
//!
//!Throws: nothing.
pointer release()
{
pointer tmp = ptr_.first();
ptr_.first() = 0;
return tmp;
}
//!Effects: If p == get() there are no effects. Otherwise get_deleter()(get()).
//!
//!Postconditions: get() == p.
//!
//!Throws: nothing.
void reset(pointer p = 0)
{
if (ptr_.first() != p){
if (ptr_.first())
ptr_.second()(ptr_.first());
ptr_.first() = p;
}
}
//!Requires: The deleter D is Swappable and will not throw an exception under swap.
//!
//!Effects: The stored pointers of this and u are exchanged.
//! The stored deleters are swapped (unqualified).
//!Throws: nothing.
void swap(unique_ptr& u)
{ ptr_.swap(u.ptr_); }
/// @cond
private:
boost::compressed_pair<pointer, D> ptr_;
BOOST_MOVABLE_BUT_NOT_COPYABLE(unique_ptr)
template <class U, class E> unique_ptr(unique_ptr<U, E>&);
template <class U> unique_ptr(U&, typename ipcdetail::unique_ptr_error<U>::type = 0);
template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&);
template <class U> typename ipcdetail::unique_ptr_error<U>::type operator=(U&);
/// @endcond
};
/*
template <class T, class D>
class unique_ptr<T[], D>
{
struct nat {int for_bool_;};
typedef typename ipcdetail::add_reference<D>::type deleter_reference;
typedef typename ipcdetail::add_reference<const D>::type deleter_const_reference;
public:
typedef T element_type;
typedef D deleter_type;
typedef typename ipcdetail::pointer_type<T, D>::type pointer;
// constructors
unique_ptr() : ptr_(pointer()) {}
explicit unique_ptr(pointer p) : ptr_(p) {}
unique_ptr(pointer p, typename if_<
boost::is_reference<D>,
D,
typename ipcdetail::add_reference<const D>::type>::type d)
: ptr_(p, d) {}
unique_ptr(const unique_ptr& u)
: ptr_(const_cast<unique_ptr&>(u).release(), u.get_deleter()) {}
// destructor
~unique_ptr() {reset();}
// assignment
unique_ptr& operator=(const unique_ptr& cu)
{
unique_ptr& u = const_cast<unique_ptr&>(cu);
reset(u.release());
ptr_.second() = u.get_deleter();
return *this;
}
unique_ptr& operator=(int nat::*)
{
reset();
return *this;
}
// observers
typename ipcdetail::add_reference<T>::type operator[](std::size_t i) const {return ptr_.first()[i];}
pointer get() const {return ptr_.first();}
deleter_reference get_deleter() {return ptr_.second();}
deleter_const_reference get_deleter() const {return ptr_.second();}
operator int nat::*() const {return ptr_.first() ? &nat::for_bool_ : 0;}
// modifiers
pointer release()
{
pointer tmp = ptr_.first();
ptr_.first() = 0;
return tmp;
}
void reset(pointer p = 0)
{
if (ptr_.first() != p)
{
if (ptr_.first())
ptr_.second()(ptr_.first());
ptr_.first() = p;
}
}
void swap(unique_ptr& u) {ptr_.swap(u.ptr_);}
private:
boost::compressed_pair<pointer, D> ptr_;
template <class U, class E> unique_ptr(U p, E,
typename boost::enable_if<boost::is_convertible<U, pointer> >::type* = 0);
template <class U> explicit unique_ptr(U,
typename boost::enable_if<boost::is_convertible<U, pointer> >::type* = 0);
unique_ptr(unique_ptr&);
template <class U> unique_ptr(U&, typename ipcdetail::unique_ptr_error<U>::type = 0);
unique_ptr& operator=(unique_ptr&);
template <class U> typename ipcdetail::unique_ptr_error<U>::type operator=(U&);
};
template <class T, class D, std::size_t N>
class unique_ptr<T[N], D>
{
struct nat {int for_bool_;};
typedef typename ipcdetail::add_reference<D>::type deleter_reference;
typedef typename ipcdetail::add_reference<const D>::type deleter_const_reference;
public:
typedef T element_type;
typedef D deleter_type;
typedef typename ipcdetail::pointer_type<T, D>::type pointer;
static const std::size_t size = N;
// constructors
unique_ptr() : ptr_(0) {}
explicit unique_ptr(pointer p) : ptr_(p) {}
unique_ptr(pointer p, typename if_<
boost::is_reference<D>,
D,
typename ipcdetail::add_reference<const D>::type>::type d)
: ptr_(p, d) {}
unique_ptr(const unique_ptr& u)
: ptr_(const_cast<unique_ptr&>(u).release(), u.get_deleter()) {}
// destructor
~unique_ptr() {reset();}
// assignment
unique_ptr& operator=(const unique_ptr& cu)
{
unique_ptr& u = const_cast<unique_ptr&>(cu);
reset(u.release());
ptr_.second() = u.get_deleter();
return *this;
}
unique_ptr& operator=(int nat::*)
{
reset();
return *this;
}
// observers
typename ipcdetail::add_reference<T>::type operator[](std::size_t i) const {return ptr_.first()[i];}
pointer get() const {return ptr_.first();}
deleter_reference get_deleter() {return ptr_.second();}
deleter_const_reference get_deleter() const {return ptr_.second();}
operator int nat::*() const {return ptr_.first() ? &nat::for_bool : 0;}
// modifiers
pointer release()
{
pointer tmp = ptr_.first();
ptr_.first() = 0;
return tmp;
}
void reset(pointer p = 0)
{
if (ptr_.first() != p)
{
if (ptr_.first())
ptr_.second()(ptr_.first(), N);
ptr_.first() = p;
}
}
void swap(unique_ptr& u) {ptr_.swap(u.ptr_);}
private:
boost::compressed_pair<pointer, D> ptr_;
template <class U, class E> unique_ptr(U p, E,
typename boost::enable_if<boost::is_convertible<U, pointer> >::type* = 0);
template <class U> explicit unique_ptr(U,
typename boost::enable_if<boost::is_convertible<U, pointer> >::type* = 0);
unique_ptr(unique_ptr&);
template <class U> unique_ptr(U&, typename ipcdetail::unique_ptr_error<U>::type = 0);
unique_ptr& operator=(unique_ptr&);
template <class U> typename ipcdetail::unique_ptr_error<U>::type operator=(U&);
};
*/
template <class T, class D> inline
void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y)
{ x.swap(y); }
template <class T1, class D1, class T2, class D2> inline
bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() == y.get(); }
template <class T1, class D1, class T2, class D2> inline
bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() != y.get(); }
template <class T1, class D1, class T2, class D2> inline
bool operator <(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() < y.get(); }
template <class T1, class D1, class T2, class D2> inline
bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() <= y.get(); }
template <class T1, class D1, class T2, class D2> inline
bool operator >(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() > y.get(); }
template <class T1, class D1, class T2, class D2> inline
bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y)
{ return x.get() >= y.get(); }
//!Returns the type of a unique pointer
//!of type T with boost::interprocess::deleter deleter
//!that can be constructed in the given managed segment type.
template<class T, class ManagedMemory>
struct managed_unique_ptr
{
typedef unique_ptr
< T
, typename ManagedMemory::template deleter<T>::type
> type;
};
//!Returns an instance of a unique pointer constructed
//!with boost::interproces::deleter from a pointer
//!of type T that has been allocated in the passed managed segment
template<class T, class ManagedMemory>
inline typename managed_unique_ptr<T, ManagedMemory>::type
make_managed_unique_ptr(T *constructed_object, ManagedMemory &managed_memory)
{
return typename managed_unique_ptr<T, ManagedMemory>::type
(constructed_object, managed_memory.template get_deleter<T>());
}
} //namespace interprocess{
} //namespace boost{
#include <boost/interprocess/detail/config_end.hpp>
#endif //#ifndef BOOST_INTERPROCESS_UNIQUE_PTR_HPP_INCLUDED