lockfree/detail/parameter.hpp

0001 // boost lockfree
0002 //
0003 // Copyright (C) 2011, 2016 Tim Blechmann
0004 //
0005 // Distributed under the Boost Software License, Version 1.0. (See
0006 // accompanying file LICENSE_1_0.txt or copy at
0007 // http://www.boost.org/LICENSE_1_0.txt)
0008
0009 #ifndef BOOST_LOCKFREE_DETAIL_PARAMETER_HPP
0010 #define BOOST_LOCKFREE_DETAIL_PARAMETER_HPP
0011
0012 #include <boost/align/aligned_allocator.hpp>
0013 #include <boost/core/allocator_access.hpp>
0014 #include <boost/lockfree/detail/prefix.hpp>
0015 #include <boost/lockfree/policies.hpp>
0016 #include <boost/parameter/binding.hpp>
0017 #include <boost/parameter/parameters.hpp>
0018
0019 #include <boost/mpl/void.hpp>
0020
0021
0022
0023 namespace boost {
0024 namespace lockfree {
0025 namespace detail {
0026
0027 namespace mpl = boost::mpl;
0028
0029 template <typename bound_args, typename tag_type>
0030 struct has_arg
0031 {
0032     typedef typename parameter::binding<bound_args, tag_type, mpl::void_>::type type;
0033     static const bool value = mpl::is_not_void_<type>::type::value;
0034 };
0035
0036
0037 template <typename bound_args>
0038 struct extract_capacity
0039 {
0040     static const bool has_capacity = has_arg<bound_args, tag::capacity>::value;
0041
0042     typedef typename mpl::if_c<has_capacity,
0043                                typename has_arg<bound_args, tag::capacity>::type,
0044                                mpl::size_t< 0 >
0045                               >::type capacity_t;
0046
0047     static const std::size_t capacity = capacity_t::value;
0048 };
0049
0050
0051 template <typename bound_args, typename T>
0052 struct extract_allocator
0053 {
0054     static const bool has_allocator = has_arg<bound_args, tag::allocator>::value;
0055
0056     typedef typename mpl::if_c<has_allocator,
0057                                typename has_arg<bound_args, tag::allocator>::type,
0058                                boost::alignment::aligned_allocator<T, BOOST_LOCKFREE_CACHELINE_BYTES>
0059                               >::type allocator_arg;
0060
0061     typedef typename boost::allocator_rebind<allocator_arg, T>::type type;
0062 };
0063
0064 template <typename bound_args, bool default_ = false>
0065 struct extract_fixed_sized
0066 {
0067     static const bool has_fixed_sized = has_arg<bound_args, tag::fixed_sized>::value;
0068
0069     typedef typename mpl::if_c<has_fixed_sized,
0070                                typename has_arg<bound_args, tag::fixed_sized>::type,
0071                                mpl::bool_<default_>
0072                               >::type type;
0073
0074     static const bool value = type::value;
0075 };
0076
0077
0078 } /* namespace detail */
0079 } /* namespace lockfree */
0080 } /* namespace boost */
0081
0082 #endif /* BOOST_LOCKFREE_DETAIL_PARAMETER_HPP */