boost/interprocess/detail/move.hpp
//////////////////////////////////////////////////////////////////////////////
//
// (C) Copyright David Abrahams, Vicente Botet, Ion Gaztanaga 2009.
// 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/move for documentation.
//
//////////////////////////////////////////////////////////////////////////////
//
// Parts of this file come from Adobe's Move library:
//
// Copyright 2005-2007 Adobe Systems Incorporated
// Distributed under the MIT License (see accompanying file LICENSE_1_0_0.txt
// or a copy at http://stlab.adobe.com/licenses.html)
//
//////////////////////////////////////////////////////////////////////////////
//! \file
#ifndef BOOST_INTERPROCESS_MOVE_HPP
#define BOOST_INTERPROCESS_MOVE_HPP
#include <boost/config.hpp>
#include <algorithm> //copy, copy_backward
#include <memory> //uninitialized_copy
#include <iterator> //std::iterator
#include <boost/mpl/if.hpp>
#include <boost/utility/enable_if.hpp>
#include <boost/type_traits/has_trivial_destructor.hpp>
namespace boost {
namespace interprocess {
namespace move_detail {
template <class T>
struct identity
{
typedef T type;
};
template <class T, class U>
class is_convertible
{
typedef char true_t;
class false_t { char dummy[2]; };
static true_t dispatch(U);
static false_t dispatch(...);
static T trigger();
public:
enum { value = sizeof(dispatch(trigger())) == sizeof(true_t) };
};
} //namespace move_detail {
} //namespace interprocess {
} //namespace boost {
#if !defined(BOOST_HAS_RVALUE_REFS) && !defined(BOOST_MOVE_DOXYGEN_INVOKED)
namespace boost {
namespace interprocess {
//////////////////////////////////////////////////////////////////////////////
//
// struct rv
//
//////////////////////////////////////////////////////////////////////////////
template <class T>
class rv : public T
{
rv();
~rv();
rv(rv const&);
void operator=(rv const&);
public:
//T &get() { return *this; }
};
//////////////////////////////////////////////////////////////////////////////
//
// move_detail::is_rv
//
//////////////////////////////////////////////////////////////////////////////
namespace move_detail {
template <class T>
struct is_rv
{
static const bool value = false;
};
template <class T>
struct is_rv< rv<T> >
{
static const bool value = true;
};
} //namespace move_detail {
//////////////////////////////////////////////////////////////////////////////
//
// is_movable
//
//////////////////////////////////////////////////////////////////////////////
template<class T>
class is_movable
{
public:
static const bool value = move_detail::is_convertible<T, rv<T>&>::value;
};
template<class T>
class is_movable< rv<T> >
{
public:
static const bool value = false;
};
//////////////////////////////////////////////////////////////////////////////
//
// move()
//
//////////////////////////////////////////////////////////////////////////////
template <class T>
typename boost::disable_if<is_movable<T>, T&>::type move(T& x)
{
return x;
}
template <class T>
typename enable_if<is_movable<T>, rv<T>&>::type move(T& x)
{
return reinterpret_cast<rv<T>& >(x);
}
template <class T>
typename enable_if<is_movable<T>, rv<T>&>::type move(const rv<T>& x)
{
return const_cast<rv<T>& >(x);
}
//////////////////////////////////////////////////////////////////////////////
//
// forward()
//
//////////////////////////////////////////////////////////////////////////////
template <class T>
typename enable_if<boost::interprocess::move_detail::is_rv<T>, T &>::type
forward(const typename move_detail::identity<T>::type &x)
{
return const_cast<T&>(x);
}
/*
template <class T>
typename enable_if<boost::interprocess::move_detail::is_rv<T>, T &>::type
forward(typename move_detail::identity<T>::type &x)
{
return x;
}
template <class T>
typename disable_if<boost::interprocess::move_detail::is_rv<T>, T &>::type
forward(typename move_detail::identity<T>::type &x)
{
return x;
}
*/
template <class T>
typename disable_if<boost::interprocess::move_detail::is_rv<T>, const T &>::type
forward(const typename move_detail::identity<T>::type &x)
{
return x;
}
//////////////////////////////////////////////////////////////////////////////
//
// BOOST_INTERPROCESS_ENABLE_MOVE_EMULATION
//
//////////////////////////////////////////////////////////////////////////////
#define BOOST_INTERPROCESS_ENABLE_MOVE_EMULATION(TYPE)\
operator boost::interprocess::rv<TYPE>&() \
{ return reinterpret_cast<boost::interprocess::rv<TYPE>& >(*this); }\
//
#define BOOST_INTERPROCESS_RV_REF(TYPE)\
boost::interprocess::rv< TYPE >& \
//
#define BOOST_INTERPROCESS_RV_REF_2_TEMPL_ARGS(TYPE, ARG1, ARG2)\
boost::interprocess::rv< TYPE<ARG1, ARG2> >& \
//
#define BOOST_INTERPROCESS_RV_REF_3_TEMPL_ARGS(TYPE, ARG1, ARG2, ARG3)\
boost::interprocess::rv< TYPE<ARG1, ARG2, ARG3> >& \
//
#define BOOST_INTERPROCESS_FWD_REF(TYPE)\
const TYPE & \
//
} //namespace interprocess {
} //namespace boost
#else //BOOST_HAS_RVALUE_REFS
#include <boost/type_traits/remove_reference.hpp>
namespace boost {
namespace interprocess {
//////////////////////////////////////////////////////////////////////////////
//
// is_movable
//
//////////////////////////////////////////////////////////////////////////////
//! For compilers with rvalue references, this traits class returns true
//! if T && is convertible to T.
//!
//! For other compilers returns true if T is convertible to <i>boost::interprocess::rv<T>&</i>
template<class T>
class is_movable
{
public:
static const bool value = move_detail::is_convertible<T&&, T>::value;
};
//////////////////////////////////////////////////////////////////////////////
//
// move
//
//////////////////////////////////////////////////////////////////////////////
#if defined(BOOST_MOVE_DOXYGEN_INVOKED)
//! This function provides a way to convert a reference into a rvalue reference
//! in compilers with rvalue reference. For other compilers converts T & into
//! <i>boost::interprocess::rv<T> &</i> so that move emulation is activated.
template <class T> inline
rvalue_reference move (input_reference);
#else
template <class T> inline
typename remove_reference<T>::type&& move(T&& t)
{ return t; }
#endif
//////////////////////////////////////////////////////////////////////////////
//
// forward
//
//////////////////////////////////////////////////////////////////////////////
#if defined(BOOST_MOVE_DOXYGEN_INVOKED)
//! This function provides limited form of forwarding that is usually enough for
//! in-place construction and avoids the exponential overloading necessary for
//! perfect forwarding in C++03.
//!
//! For compilers with rvalue references this function provides perfect forwarding.
//!
//! Otherwise:
//! * If input_reference binds to const boost::interprocess::rv<T> & then it output_reference is
//! boost::rev<T> &
//!
//! * Else, input_reference is equal to output_reference is equal to input_reference.
template <class T> inline output_reference forward(input_reference);
#else
template <class T> inline
T&& forward (typename move_detail::identity<T>::type&& t)
{ return t; }
#endif
//////////////////////////////////////////////////////////////////////////////
//
// BOOST_INTERPROCESS_ENABLE_MOVE_EMULATION
//
//////////////////////////////////////////////////////////////////////////////
//! This macro expands to nothing for compilers with rvalue references.
//! Otherwise expands to:
//! \code
//! operator boost::interprocess::rv<TYPE>&()
//! { return static_cast<boost::interprocess::rv<TYPE>& >(*this); }
//! \endcode
#define BOOST_INTERPROCESS_ENABLE_MOVE_EMULATION(TYPE)\
//
#define BOOST_INTERPROCESS_RV_REF_2_TEMPL_ARGS(TYPE, ARG1, ARG2)\
TYPE<ARG1, ARG2> && \
//
#define BOOST_INTERPROCESS_RV_REF_3_TEMPL_ARGS(TYPE, ARG1, ARG2, ARG3)\
TYPE<ARG1, ARG2, ARG3> && \
//
//! This macro expands to <i>T&&</i> for compilers with rvalue references.
//! Otherwise expands to <i>boost::interprocess::rv<T> &</i>.
#define BOOST_INTERPROCESS_RV_REF(TYPE)\
TYPE && \
//
//! This macro expands to <i>T&&</i> for compilers with rvalue references.
//! Otherwise expands to <i>const T &</i>.
#define BOOST_INTERPROCESS_FWD_REF(TYPE)\
TYPE && \
//
} //namespace interprocess {
} //namespace boost {
#endif //BOOST_HAS_RVALUE_REFS
namespace boost {
namespace interprocess {
//////////////////////////////////////////////////////////////////////////////
//
// move_iterator
//
//////////////////////////////////////////////////////////////////////////////
//! Class template move_iterator is an iterator adaptor with the same behavior
//! as the underlying iterator except that its dereference operator implicitly
//! converts the value returned by the underlying iterator's dereference operator
//! to an rvalue reference. Some generic algorithms can be called with move
//! iterators to replace copying with moving.
template <class It>
class move_iterator
{
public:
typedef It iterator_type;
typedef typename std::iterator_traits<iterator_type>::value_type value_type;
#if defined(BOOST_HAS_RVALUE_REFS) || defined(BOOST_MOVE_DOXYGEN_INVOKED)
typedef value_type && reference;
#else
typedef typename boost::mpl::if_
< boost::interprocess::is_movable<value_type>
, boost::interprocess::rv<value_type>&
, value_type & >::type reference;
#endif
typedef typename std::iterator_traits<iterator_type>::pointer pointer;
typedef typename std::iterator_traits<iterator_type>::difference_type difference_type;
typedef typename std::iterator_traits<iterator_type>::iterator_category iterator_category;
move_iterator()
{}
explicit move_iterator(It i)
: m_it(i)
{}
template <class U>
move_iterator(const move_iterator<U>& u)
: m_it(u.base())
{}
iterator_type base() const
{ return m_it; }
reference operator*() const
{
#if defined(BOOST_HAS_RVALUE_REFS)
return *m_it;
#else
return boost::interprocess::move(*m_it);
#endif
}
pointer operator->() const
{ return m_it; }
move_iterator& operator++()
{ ++m_it; return *this; }
move_iterator<iterator_type> operator++(int)
{ move_iterator<iterator_type> tmp(*this); ++(*this); return tmp; }
move_iterator& operator--()
{ --m_it; return *this; }
move_iterator<iterator_type> operator--(int)
{ move_iterator<iterator_type> tmp(*this); --(*this); return tmp; }
move_iterator<iterator_type> operator+ (difference_type n) const
{ return move_iterator<iterator_type>(m_it + n); }
move_iterator& operator+=(difference_type n)
{ m_it += n; return *this; }
move_iterator<iterator_type> operator- (difference_type n) const
{ return move_iterator<iterator_type>(m_it - n); }
move_iterator& operator-=(difference_type n)
{ m_it -= n; return *this; }
reference operator[](difference_type n) const
{
#if defined(BOOST_HAS_RVALUE_REFS)
return m_it[n];
#else
return boost::interprocess::move(m_it[n]);
#endif
}
friend bool operator==(const move_iterator& x, const move_iterator& y)
{ return x.base() == y.base(); }
friend bool operator!=(const move_iterator& x, const move_iterator& y)
{ return x.base() != y.base(); }
friend bool operator< (const move_iterator& x, const move_iterator& y)
{ return x.base() < y.base(); }
friend bool operator<=(const move_iterator& x, const move_iterator& y)
{ return x.base() <= y.base(); }
friend bool operator> (const move_iterator& x, const move_iterator& y)
{ return x.base() > y.base(); }
friend bool operator>=(const move_iterator& x, const move_iterator& y)
{ return x.base() >= y.base(); }
friend difference_type operator-(const move_iterator& x, const move_iterator& y)
{ return x.base() - y.base(); }
friend move_iterator operator+(difference_type n, const move_iterator& x)
{ return move_iterator(x.base() + n); }
private:
It m_it;
};
//is_move_iterator
namespace move_detail {
template <class I>
struct is_move_iterator
{
static const bool value = false;
};
template <class I>
struct is_move_iterator< ::boost::interprocess::move_iterator<I> >
{
static const bool value = true;
};
} //namespace move_detail {
//////////////////////////////////////////////////////////////////////////////
//
// move_iterator
//
//////////////////////////////////////////////////////////////////////////////
//!
//! <b>Returns</b>: move_iterator<It>(i).
template<class It>
move_iterator<It> make_move_iterator(const It &it)
{ return move_iterator<It>(it); }
//////////////////////////////////////////////////////////////////////////////
//
// back_move_insert_iterator
//
//////////////////////////////////////////////////////////////////////////////
//! A move insert iterator that move constructs elements at the
//! back of a container
template <typename C> // C models Container
class back_move_insert_iterator
: public std::iterator<std::output_iterator_tag, void, void, void, void>
{
C* container_m;
public:
typedef C container_type;
explicit back_move_insert_iterator(C& x) : container_m(&x) { }
back_move_insert_iterator& operator=(typename C::reference x)
{ container_m->push_back(boost::interprocess::move(x)); return *this; }
back_move_insert_iterator& operator*() { return *this; }
back_move_insert_iterator& operator++() { return *this; }
back_move_insert_iterator& operator++(int) { return *this; }
};
//!
//! <b>Returns</b>: back_move_insert_iterator<C>(x).
template <typename C> // C models Container
inline back_move_insert_iterator<C> back_move_inserter(C& x)
{
return back_move_insert_iterator<C>(x);
}
//////////////////////////////////////////////////////////////////////////////
//
// front_move_insert_iterator
//
//////////////////////////////////////////////////////////////////////////////
//! A move insert iterator that move constructs elements int the
//! front of a container
template <typename C> // C models Container
class front_move_insert_iterator
: public std::iterator<std::output_iterator_tag, void, void, void, void>
{
C* container_m;
public:
typedef C container_type;
explicit front_move_insert_iterator(C& x) : container_m(&x) { }
front_move_insert_iterator& operator=(typename C::reference x)
{ container_m->push_front(boost::interprocess::move(x)); return *this; }
front_move_insert_iterator& operator*() { return *this; }
front_move_insert_iterator& operator++() { return *this; }
front_move_insert_iterator& operator++(int) { return *this; }
};
//!
//! <b>Returns</b>: front_move_insert_iterator<C>(x).
template <typename C> // C models Container
inline front_move_insert_iterator<C> front_move_inserter(C& x)
{
return front_move_insert_iterator<C>(x);
}
//////////////////////////////////////////////////////////////////////////////
//
// insert_move_iterator
//
//////////////////////////////////////////////////////////////////////////////
template <typename C> // C models Container
class move_insert_iterator
: public std::iterator<std::output_iterator_tag, void, void, void, void>
{
C* container_m;
typename C::iterator pos_;
public:
typedef C container_type;
explicit move_insert_iterator(C& x, typename C::iterator pos)
: container_m(&x), pos_(pos)
{}
move_insert_iterator& operator=(typename C::reference x)
{
pos_ = container_m->insert(pos_, boost::interprocess::move(x));
++pos_;
return *this;
}
move_insert_iterator& operator*() { return *this; }
move_insert_iterator& operator++() { return *this; }
move_insert_iterator& operator++(int) { return *this; }
};
//!
//! <b>Returns</b>: move_insert_iterator<C>(x, it).
template <typename C> // C models Container
inline move_insert_iterator<C> move_inserter(C& x, typename C::iterator it)
{
return move_insert_iterator<C>(x, it);
}
//////////////////////////////////////////////////////////////////////////////
//
// move
//
//////////////////////////////////////////////////////////////////////////////
//! <b>Effects</b>: Moves elements in the range [first,last) into the range [result,result + (last -
//! first)) starting from first and proceeding to last. For each non-negative integer n < (last-first),
//! performs *(result + n) = boost::interprocess::move (*(first + n)).
//!
//! <b>Effects</b>: result + (last - first).
//!
//! <b>Requires</b>: result shall not be in the range [first,last).
//!
//! <b>Complexity</b>: Exactly last - first move assignments.
template <typename I, // I models InputIterator
typename O> // O models OutputIterator
O move(I f, I l, O result)
{
while (f != l) {
*result = boost::interprocess::move(*f);
++f; ++result;
}
return result;
}
//////////////////////////////////////////////////////////////////////////////
//
// move_backward
//
//////////////////////////////////////////////////////////////////////////////
//! <b>Effects</b>: Moves elements in the range [first,last) into the range
//! [result - (last-first),result) starting from last - 1 and proceeding to
//! first. For each positive integer n <= (last - first),
//! performs *(result - n) = boost::interprocess::move(*(last - n)).
//!
//! <b>Requires</b>: result shall not be in the range [first,last).
//!
//! <b>Returns</b>: result - (last - first).
//!
//! <b>Complexity</b>: Exactly last - first assignments.
template <typename I, // I models BidirectionalIterator
typename O> // O models BidirectionalIterator
O move_backward(I f, I l, O result)
{
while (f != l) {
--l; --result;
*result = boost::interprocess::move(*l);
}
return result;
}
//////////////////////////////////////////////////////////////////////////////
//
// uninitialized_move
//
//////////////////////////////////////////////////////////////////////////////
//! <b>Effects</b>:
//! \code
//! for (; first != last; ++result, ++first)
//! new (static_cast<void*>(&*result))
//! typename iterator_traits<ForwardIterator>::value_type(boost::interprocess::move(*first));
//! \endcode
//!
//! <b>Returns</b>: result
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_move(I f, I l, F r
/// @cond
,typename enable_if<is_movable<typename std::iterator_traits<I>::value_type> >::type* = 0
/// @endcond
)
{
typedef typename std::iterator_traits<I>::value_type input_value_type;
while (f != l) {
::new(static_cast<void*>(&*r)) input_value_type(boost::interprocess::move(*f));
++f; ++r;
}
return r;
}
/// @cond
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_move(I f, I l, F r,
typename disable_if<is_movable<typename std::iterator_traits<I>::value_type> >::type* = 0)
{
return std::uninitialized_copy(f, l, r);
}
//////////////////////////////////////////////////////////////////////////////
//
// uninitialized_copy_or_move
//
//////////////////////////////////////////////////////////////////////////////
namespace move_detail {
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_move_move_iterator(I f, I l, F r,
typename enable_if< is_movable<typename I::value_type> >::type* = 0)
{
return boost::interprocess::uninitialized_move(f, l, r);
}
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_move_move_iterator(I f, I l, F r,
typename disable_if< is_movable<typename I::value_type> >::type* = 0)
{
return std::uninitialized_copy(f.base(), l.base(), r);
}
} //namespace move_detail {
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_copy_or_move(I f, I l, F r,
typename enable_if< move_detail::is_move_iterator<I> >::type* = 0)
{
return boost::interprocess::move_detail::uninitialized_move_move_iterator(f, l, r);
}
/// @endcond
//! <b>Effects</b>:
//! \code
//! for (; first != last; ++result, ++first)
//! new (static_cast<void*>(&*result))
//! typename iterator_traits<ForwardIterator>::value_type(*first);
//! \endcode
//!
//! <b>Returns</b>: result
//!
//! <b>Note</b>: This function is provided because
//! <i>std::uninitialized_copy</i> from some STL implementations
//! is not compatible with <i>move_iterator</i>
template
<typename I, // I models InputIterator
typename F> // F models ForwardIterator
F uninitialized_copy_or_move(I f, I l, F r
/// @cond
,typename disable_if< move_detail::is_move_iterator<I> >::type* = 0
/// @endcond
)
{
return std::uninitialized_copy(f, l, r);
}
///has_trivial_destructor_after_move<> == true_type
///specialization for optimizations
template <class T>
struct has_trivial_destructor_after_move
: public boost::has_trivial_destructor<T>
{};
} //namespace interprocess {
} //namespace boost {
#endif //#ifndef BOOST_INTERPROCESS_MOVE_HPP