boost/log/detail/light_function.hpp
/*
* Copyright Andrey Semashev 2007 - 2015.
* 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)
*/
/*!
* \file light_function.hpp
* \author Andrey Semashev
* \date 20.06.2010
*
* \brief This header is the Boost.Log library impl, see the library documentation
* at http://www.boost.org/doc/libs/release/libs/log/doc/html/index.html.
*
* The file contains a lightweight alternative of Boost.Function. It does not provide all
* features of Boost.Function but doesn't introduce dependency on Boost.Bind.
*/
#ifndef BOOST_LOG_DETAIL_LIGHT_FUNCTION_HPP_INCLUDED_
#define BOOST_LOG_DETAIL_LIGHT_FUNCTION_HPP_INCLUDED_
#include <cstddef>
#include <boost/move/core.hpp>
#include <boost/move/utility_core.hpp>
#include <boost/core/explicit_operator_bool.hpp>
#include <boost/log/detail/config.hpp>
#include <boost/type_traits/remove_cv.hpp>
#if defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
#include <boost/preprocessor/iteration/iterate.hpp>
#include <boost/preprocessor/repetition/enum_params.hpp>
#include <boost/preprocessor/repetition/enum_binary_params.hpp>
#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
#include <boost/preprocessor/repetition/enum_trailing_binary_params.hpp>
#endif
#if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
#include <boost/log/detail/sfinae_tools.hpp>
#else
#include <boost/type_traits/remove_reference.hpp>
#endif
#if defined(BOOST_NO_CXX11_NULLPTR)
#include <boost/assert.hpp>
#endif
#include <boost/log/detail/header.hpp>
#ifdef BOOST_HAS_PRAGMA_ONCE
#pragma once
#endif
#ifndef BOOST_LOG_LIGHT_FUNCTION_LIMIT
#define BOOST_LOG_LIGHT_FUNCTION_LIMIT 2
#endif
namespace boost {
BOOST_LOG_OPEN_NAMESPACE
namespace aux {
#if defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
template< typename T, typename ThisT >
struct is_cv_same { enum _ { value = false }; };
template< typename T >
struct is_cv_same< T, T > { enum _ { value = true }; };
template< typename T >
struct is_cv_same< T, const T > { enum _ { value = true }; };
template< typename T >
struct is_cv_same< T, volatile T > { enum _ { value = true }; };
template< typename T >
struct is_cv_same< T, const volatile T > { enum _ { value = true }; };
template< typename T, typename ThisT >
struct is_rv_or_same { enum _ { value = false }; };
template< typename T >
struct is_rv_or_same< T, T > { enum _ { value = true }; };
template< typename T, typename ThisT >
struct is_rv_or_same< boost::rv< T >, ThisT > { enum _ { value = true }; };
#endif
template< typename SignatureT >
class light_function;
#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
template< typename ResultT, typename... ArgsT >
class light_function< ResultT (ArgsT...) >
{
typedef light_function this_type;
BOOST_COPYABLE_AND_MOVABLE(this_type)
public:
typedef ResultT result_type;
private:
struct impl_base
{
typedef result_type (*invoke_type)(void*, ArgsT...);
const invoke_type invoke;
typedef impl_base* (*clone_type)(const void*);
const clone_type clone;
typedef void (*destroy_type)(void*);
const destroy_type destroy;
impl_base(invoke_type inv, clone_type cl, destroy_type dstr) : invoke(inv), clone(cl), destroy(dstr)
{
}
BOOST_DELETED_FUNCTION(impl_base(impl_base const&))
BOOST_DELETED_FUNCTION(impl_base& operator= (impl_base const&))
};
#if !defined(BOOST_LOG_NO_MEMBER_TEMPLATE_FRIENDS)
template< typename FunT >
class impl;
template< typename FunT >
friend class impl;
#endif
template< typename FunT >
class impl :
public impl_base
{
typedef impl< FunT > this_type;
FunT m_Function;
public:
explicit impl(FunT const& fun) :
impl_base(&this_type::invoke_impl, &this_type::clone_impl, &this_type::destroy_impl),
m_Function(fun)
{
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
explicit impl(FunT&& fun) :
impl_base(&this_type::invoke_impl, &this_type::clone_impl, &this_type::destroy_impl),
m_Function(boost::move(fun))
{
}
#endif // !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
static void destroy_impl(void* self)
{
delete static_cast< impl* >(static_cast< impl_base* >(self));
}
static impl_base* clone_impl(const void* self)
{
return new impl(static_cast< const impl* >(static_cast< const impl_base* >(self))->m_Function);
}
static result_type invoke_impl(void* self, ArgsT... args)
{
return static_cast< impl* >(static_cast< impl_base* >(self))->m_Function(args...);
}
BOOST_DELETED_FUNCTION(impl(impl const&))
BOOST_DELETED_FUNCTION(impl& operator= (impl const&))
};
private:
impl_base* m_pImpl;
public:
BOOST_CONSTEXPR light_function() BOOST_NOEXCEPT : m_pImpl(NULL)
{
}
light_function(this_type const& that)
{
if (that.m_pImpl)
m_pImpl = that.m_pImpl->clone(that.m_pImpl);
else
m_pImpl = NULL;
}
light_function(BOOST_RV_REF(this_type) that) BOOST_NOEXCEPT
{
m_pImpl = that.m_pImpl;
that.m_pImpl = NULL;
}
light_function(BOOST_RV_REF(const this_type) that) BOOST_NOEXCEPT
{
m_pImpl = that.m_pImpl;
((this_type&)that).m_pImpl = NULL;
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
template< typename FunT >
light_function(FunT&& fun) :
m_pImpl(new impl< typename remove_cv< typename remove_reference< FunT >::type >::type >(boost::forward< FunT >(fun)))
{
}
#else
template< typename FunT >
light_function(FunT const& fun, typename boost::disable_if_c< is_rv_or_same< FunT, this_type >::value, boost::log::aux::sfinae_dummy >::type = boost::log::aux::sfinae_dummy()) :
m_pImpl(new impl< FunT >(fun))
{
}
template< typename FunT >
light_function(BOOST_RV_REF(FunT) fun, typename boost::disable_if_c< is_cv_same< FunT, this_type >::value, boost::log::aux::sfinae_dummy >::type = boost::log::aux::sfinae_dummy()) :
m_pImpl(new impl< typename remove_cv< FunT >::type >(fun))
{
}
#endif
//! Constructor from NULL
#if !defined(BOOST_NO_CXX11_NULLPTR)
BOOST_CONSTEXPR light_function(std::nullptr_t) BOOST_NOEXCEPT
#else
BOOST_CONSTEXPR light_function(int p) BOOST_NOEXCEPT
#endif
: m_pImpl(NULL)
{
#if defined(BOOST_NO_CXX11_NULLPTR)
BOOST_ASSERT(p == 0);
#endif
}
~light_function()
{
clear();
}
light_function& operator= (BOOST_RV_REF(this_type) that) BOOST_NOEXCEPT
{
this->swap(that);
return *this;
}
light_function& operator= (BOOST_COPY_ASSIGN_REF(this_type) that)
{
light_function tmp = static_cast< this_type const& >(that);
this->swap(tmp);
return *this;
}
//! Assignment of NULL
#if !defined(BOOST_NO_CXX11_NULLPTR)
light_function& operator= (std::nullptr_t)
#else
light_function& operator= (int p)
#endif
{
#if defined(BOOST_NO_CXX11_NULLPTR)
BOOST_ASSERT(p == 0);
#endif
clear();
return *this;
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
template< typename FunT >
light_function& operator= (FunT&& fun)
{
light_function tmp(boost::forward< FunT >(fun));
this->swap(tmp);
return *this;
}
#else
template< typename FunT >
typename boost::disable_if_c< is_rv_or_same< FunT, this_type >::value, this_type& >::type
operator= (FunT const& fun)
{
light_function tmp(fun);
this->swap(tmp);
return *this;
}
#endif
result_type operator() (ArgsT... args) const
{
return m_pImpl->invoke(m_pImpl, args...);
}
BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()
bool operator! () const BOOST_NOEXCEPT { return (m_pImpl == NULL); }
bool empty() const BOOST_NOEXCEPT { return (m_pImpl == NULL); }
void clear() BOOST_NOEXCEPT
{
if (m_pImpl)
{
m_pImpl->destroy(m_pImpl);
m_pImpl = NULL;
}
}
void swap(this_type& that) BOOST_NOEXCEPT
{
impl_base* p = m_pImpl;
m_pImpl = that.m_pImpl;
that.m_pImpl = p;
}
};
template< typename... ArgsT >
class light_function< void (ArgsT...) >
{
typedef light_function this_type;
BOOST_COPYABLE_AND_MOVABLE(this_type)
public:
typedef void result_type;
private:
struct impl_base
{
typedef void (*invoke_type)(void*, ArgsT...);
const invoke_type invoke;
typedef impl_base* (*clone_type)(const void*);
const clone_type clone;
typedef void (*destroy_type)(void*);
const destroy_type destroy;
impl_base(invoke_type inv, clone_type cl, destroy_type dstr) : invoke(inv), clone(cl), destroy(dstr)
{
}
BOOST_DELETED_FUNCTION(impl_base(impl_base const&))
BOOST_DELETED_FUNCTION(impl_base& operator= (impl_base const&))
};
#if !defined(BOOST_LOG_NO_MEMBER_TEMPLATE_FRIENDS)
template< typename FunT >
class impl;
template< typename FunT >
friend class impl;
#endif
template< typename FunT >
class impl :
public impl_base
{
typedef impl< FunT > this_type;
FunT m_Function;
public:
explicit impl(FunT const& fun) :
impl_base(&this_type::invoke_impl, &this_type::clone_impl, &this_type::destroy_impl),
m_Function(fun)
{
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
explicit impl(FunT&& fun) :
impl_base(&this_type::invoke_impl, &this_type::clone_impl, &this_type::destroy_impl),
m_Function(boost::move(fun))
{
}
#endif // !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
static void destroy_impl(void* self)
{
delete static_cast< impl* >(static_cast< impl_base* >(self));
}
static impl_base* clone_impl(const void* self)
{
return new impl(static_cast< const impl* >(static_cast< const impl_base* >(self))->m_Function);
}
static result_type invoke_impl(void* self, ArgsT... args)
{
static_cast< impl* >(static_cast< impl_base* >(self))->m_Function(args...);
}
BOOST_DELETED_FUNCTION(impl(impl const&))
BOOST_DELETED_FUNCTION(impl& operator= (impl const&))
};
private:
impl_base* m_pImpl;
public:
BOOST_CONSTEXPR light_function() BOOST_NOEXCEPT : m_pImpl(NULL)
{
}
light_function(this_type const& that)
{
if (that.m_pImpl)
m_pImpl = that.m_pImpl->clone(that.m_pImpl);
else
m_pImpl = NULL;
}
light_function(BOOST_RV_REF(this_type) that) BOOST_NOEXCEPT
{
m_pImpl = that.m_pImpl;
that.m_pImpl = NULL;
}
light_function(BOOST_RV_REF(const this_type) that) BOOST_NOEXCEPT
{
m_pImpl = that.m_pImpl;
((this_type&)that).m_pImpl = NULL;
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
template< typename FunT >
light_function(FunT&& fun) :
m_pImpl(new impl< typename remove_cv< typename remove_reference< FunT >::type >::type >(boost::forward< FunT >(fun)))
{
}
#else
template< typename FunT >
light_function(FunT const& fun, typename boost::disable_if_c< is_rv_or_same< FunT, this_type >::value, boost::log::aux::sfinae_dummy >::type = boost::log::aux::sfinae_dummy()) :
m_pImpl(new impl< FunT >(fun))
{
}
template< typename FunT >
light_function(BOOST_RV_REF(FunT) fun, typename boost::disable_if_c< is_cv_same< FunT, this_type >::value, boost::log::aux::sfinae_dummy >::type = boost::log::aux::sfinae_dummy()) :
m_pImpl(new impl< typename remove_cv< FunT >::type >(fun))
{
}
#endif
//! Constructor from NULL
#if !defined(BOOST_NO_CXX11_NULLPTR)
BOOST_CONSTEXPR light_function(std::nullptr_t) BOOST_NOEXCEPT
#else
BOOST_CONSTEXPR light_function(int p) BOOST_NOEXCEPT
#endif
: m_pImpl(NULL)
{
#if defined(BOOST_NO_CXX11_NULLPTR)
BOOST_ASSERT(p == 0);
#endif
}
~light_function()
{
clear();
}
light_function& operator= (BOOST_RV_REF(this_type) that) BOOST_NOEXCEPT
{
this->swap(that);
return *this;
}
light_function& operator= (BOOST_COPY_ASSIGN_REF(this_type) that)
{
light_function tmp = static_cast< this_type const& >(that);
this->swap(tmp);
return *this;
}
//! Assignment of NULL
#if !defined(BOOST_NO_CXX11_NULLPTR)
light_function& operator= (std::nullptr_t)
#else
light_function& operator= (int p)
#endif
{
#if defined(BOOST_NO_CXX11_NULLPTR)
BOOST_ASSERT(p == 0);
#endif
clear();
return *this;
}
#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
template< typename FunT >
light_function& operator= (FunT&& fun)
{
light_function tmp(boost::forward< FunT >(fun));
this->swap(tmp);
return *this;
}
#else
template< typename FunT >
typename boost::disable_if_c< is_rv_or_same< FunT, this_type >::value, this_type& >::type
operator= (FunT const& fun)
{
light_function tmp(fun);
this->swap(tmp);
return *this;
}
#endif
result_type operator() (ArgsT... args) const
{
m_pImpl->invoke(m_pImpl, args...);
}
BOOST_EXPLICIT_OPERATOR_BOOL_NOEXCEPT()
bool operator! () const BOOST_NOEXCEPT { return (m_pImpl == NULL); }
bool empty() const BOOST_NOEXCEPT { return (m_pImpl == NULL); }
void clear() BOOST_NOEXCEPT
{
if (m_pImpl)
{
m_pImpl->destroy(m_pImpl);
m_pImpl = NULL;
}
}
void swap(this_type& that) BOOST_NOEXCEPT
{
impl_base* p = m_pImpl;
m_pImpl = that.m_pImpl;
that.m_pImpl = p;
}
};
#else // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
#define BOOST_PP_FILENAME_1 <boost/log/detail/light_function_pp.hpp>
#define BOOST_PP_ITERATION_LIMITS (0, BOOST_LOG_LIGHT_FUNCTION_LIMIT)
#include BOOST_PP_ITERATE()
#endif // !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
template< typename SignatureT >
inline void swap(light_function< SignatureT >& left, light_function< SignatureT >& right)
{
left.swap(right);
}
} // namespace aux
BOOST_LOG_CLOSE_NAMESPACE // namespace log
} // namespace boost
#include <boost/log/detail/footer.hpp>
#endif // BOOST_LOG_DETAIL_LIGHT_FUNCTION_HPP_INCLUDED_