Allocator.hpp

/*****************************************************************************
 * \file
 * \brief This header defines the concepts and type-traits relating to the
 *        Allocator concept
 *****************************************************************************/

/*
  The MIT License (MIT)

  Copyright (c) 2018 Matthew Rodusek

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  SOFTWARE.
*/
#ifndef BIT_MEMORY_CONCEPTS_ALLOCATOR_HPP
#define BIT_MEMORY_CONCEPTS_ALLOCATOR_HPP

#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)

#include "detail/identity.hpp"            // detail::identity
#include "detail/void_t.hpp"              // detail::void_t
#include "detail/allocator_utilities.hpp" // allocator_size_type

#include "../utilities/allocator_info.hpp" // allocator_info

#include <cstddef>     // std::maxalign_t
#include <type_traits> // std::declval

namespace bit {
  namespace memory {

#if __cplusplus >= 202000L
    // TODO(bitwize) replace 202000L with the correct __cplusplus when certified
    template<typename T>
    concept Allocator = requires( T a,
                                  allocator_pointer_t<T> p,
                                  allocator_size_type_t<T> size,
                                  allocator_size_type_t<T> align )
    {
      { a.try_allocate( size, align ) } -> allocator_pointer_t<T>;
      { a.deallocate( p, size ) };
    };
#endif

    namespace detail {

      //----------------------------------------------------------------------
      // Allocator traits
      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_allocate_impl : std::false_type{};

      template<typename T>
      struct allocator_has_allocate_impl<T,
        void_t<decltype(std::declval<allocator_pointer_t<T>&>()
          = std::declval<T&>().allocate( std::declval<allocator_size_type_t<T>>(),
                                         std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_allocate_hint_impl : std::false_type{};

      template<typename T>
      struct allocator_has_allocate_hint_impl<T,
        void_t<decltype(std::declval<allocator_pointer_t<T>&>()
          = std::declval<T&>().allocate( std::declval<allocator_const_pointer_t<T>>(),
                                         std::declval<allocator_size_type_t<T>>(),
                                         std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_try_allocate_impl : std::false_type{};

      template<typename T>
      struct allocator_has_try_allocate_impl<T,
        void_t<decltype(std::declval<allocator_pointer_t<T>&>()
          = std::declval<T&>().try_allocate( std::declval<allocator_size_type_t<T>>(),
                                             std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_try_allocate_hint_impl : std::false_type{};

      template<typename T>
      struct allocator_has_try_allocate_hint_impl<T,
        void_t<decltype(std::declval<allocator_pointer_t<T>&>()
          = std::declval<T&>().try_allocate( std::declval<allocator_const_pointer_t<T>>(),
                                             std::declval<allocator_size_type_t<T>>(),
                                             std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename...> struct allocator_type_list;

      //----------------------------------------------------------------------

      template<typename T, typename U, typename List, typename = void>
      struct allocator_has_construct_impl : std::false_type{};

      template<typename T, typename U, typename...Args>
      struct allocator_has_construct_impl<T,U,allocator_type_list<Args...>,
        void_t<
          decltype( std::declval<T&>().template construct<U>( std::declval<void*>(), std::declval<Args>()... ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename U, typename List, typename = void>
      struct allocator_has_make_impl : std::false_type{};

      template<typename T, typename U, typename...Args>
      struct allocator_has_make_impl<T,U,allocator_type_list<Args...>,
        void_t<
          decltype( std::declval<T&>().template make<U>( std::declval<Args>()... ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename U, typename List, typename = void>
      struct allocator_has_make_array_impl : std::false_type{};

      template<typename T, typename U, typename...Args>
      struct allocator_has_make_array_impl<T,U,allocator_type_list<Args...>,
        void_t<
          decltype( std::declval<T&>().template make_array<U>( std::declval<Args>()... ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_deallocate_impl : std::false_type{};

      template<typename T>
      struct allocator_has_deallocate_impl<T,
        void_t<decltype(std::declval<T&>().deallocate( std::declval<allocator_pointer_t<T>&>(),
                                                       std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_deallocate_all_impl : std::false_type{};

      template<typename T>
      struct allocator_has_deallocate_all_impl<T,
        void_t<decltype(std::declval<T&>().deallocate_all())>
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename, typename = void>
      struct allocator_has_destroy_impl : std::false_type{};

      template<typename T, typename U>
      struct allocator_has_destroy_impl<T,U,
        void_t<
          decltype( std::declval<T&>().dispose( std::declval<U>() ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename, typename = void>
      struct allocator_has_dispose_impl : std::false_type{};

      template<typename T, typename U>
      struct allocator_has_dispose_impl<T,U,
        void_t<
          decltype( std::declval<T&>().dispose( std::declval<U&>() ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename, typename = void>
      struct allocator_has_dispose_array_impl : std::false_type{};

      template<typename T, typename U>
      struct allocator_has_dispose_array_impl<T,U,
        void_t<
          decltype( std::declval<T&>().dispose_array( std::declval<U&>(), std::declval<allocator_size_type_t<T>>() ) )
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_recommended_allocation_size_impl : std::false_type{};

      template<typename T>
      struct allocator_has_recommended_allocation_size_impl<T,
        void_t<decltype(std::declval<allocator_size_type_t<T>&>()
          = std::declval<const T&>().recommended_allocation_size( std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_owns_impl : std::false_type{};

      template<typename T>
      struct allocator_has_owns_impl<T,
        void_t<decltype(std::declval<bool&>()
          = std::declval<const T&>().owns( std::declval<allocator_const_pointer_t<T>>() ))
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_info_impl : std::false_type{};

      template<typename T>
      struct allocator_has_info_impl<T,
        void_t<decltype( std::declval<allocator_info>() = std::declval<const T&>().info() )>
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_is_unbounded_impl : std::false_type{};

      template<typename T>
      struct allocator_has_is_unbounded_impl<T,
        void_t<decltype( std::declval<bool&>()
          = std::declval<const T&>().is_unbounded())
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_max_size_impl : std::false_type{};

      template<typename T>
      struct allocator_has_max_size_impl<T,
        void_t<decltype( std::declval<allocator_size_type_t<T>&>()
          = std::declval<const T&>().max_size())
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_min_size_impl : std::false_type{};

      template<typename T>
      struct allocator_has_min_size_impl<T,
        void_t<decltype( std::declval<allocator_size_type_t<T>&>()
          = std::declval<const T&>().min_size())
        >
      > : std::true_type{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_default_alignment_impl
        : std::integral_constant<allocator_size_type_t<T>,1>{};

      template<typename T>
      struct allocator_default_alignment_impl<T,
        void_t<decltype(T::default_alignment)>>
        : T::default_alignment{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_max_alignment_impl
        : std::integral_constant<allocator_size_type_t<T>,alignof(std::max_align_t)>{};

      template<typename T>
      struct allocator_max_alignment_impl<T,
        void_t<decltype(T::max_alignment)>>
        : std::integral_constant<allocator_size_type_t<T>,alignof(std::max_align_t)>{};

      //----------------------------------------------------------------------

      template<typename T, typename = void>
      struct allocator_has_expand : std::false_type{};

      template<typename T>
      struct allocator_has_expand<T,
        void_t<decltype(std::declval<bool&>()
          = std::declval<T&>().expand( std::declval<allocator_pointer_t<T>&>(),
                                       std::declval<allocator_size_type_t<T>>() ))
        >
      > : std::true_type{};

    } // namespace detail

    template<typename T>
    struct allocator_has_try_allocate_hint
      : detail::allocator_has_try_allocate_hint_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_try_allocate_hint_v
      = allocator_has_try_allocate_hint<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_allocate
      : detail::allocator_has_allocate_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_allocate_v
      = allocator_has_allocate<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_allocate_hint
      : detail::allocator_has_allocate_hint_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_allocate_hint_v
      = allocator_has_allocate_hint<T>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U, typename...Args>
    struct allocator_has_construct
      : detail::allocator_has_construct_impl<T,U,detail::allocator_type_list<Args...>>{};

    template<typename T, typename U, typename...Args>
    constexpr bool allocator_has_construct_v
      = allocator_has_construct<T,U,Args...>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U, typename...Args>
    struct allocator_has_make
      : detail::allocator_has_make_impl<T,U,detail::allocator_type_list<Args...>>{};

    template<typename T, typename U, typename...Args>
    constexpr bool allocator_has_make_v
      = allocator_has_make<T,U,Args...>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U, typename...Args>
    struct allocator_has_make_array
      : detail::allocator_has_make_array_impl<T,U,detail::allocator_type_list<Args...>>{};

    template<typename T, typename U, typename...Args>
    constexpr bool allocator_has_make_array_v
      = allocator_has_make_array<T,U,Args...>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_can_truncate_deallocations
      : detail::allocator_has_deallocate_all_impl<T>{};

    template<typename T>
    constexpr bool allocator_can_truncate_deallocations_v = allocator_can_truncate_deallocations<T>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U>
    struct allocator_has_destroy
      : detail::allocator_has_destroy_impl<T,U>{};

    template<typename T, typename U>
    constexpr bool allocator_has_destroy_v
      = allocator_has_destroy<T,U>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U>
    struct allocator_has_dispose
      : detail::allocator_has_dispose_impl<T,U>{};

    template<typename T, typename U>
    constexpr bool allocator_has_dispose_v
      = allocator_has_dispose<T,U>::value;

    //-------------------------------------------------------------------------

    template<typename T, typename U>
    struct allocator_has_dispose_array
      : detail::allocator_has_dispose_array_impl<T,U>{};

    template<typename T, typename U>
    constexpr bool allocator_has_dispose_array_v
      = allocator_has_dispose_array<T,U>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_recommended_allocation_size
      : detail::allocator_has_recommended_allocation_size_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_recommended_allocation_size_v
      = allocator_has_recommended_allocation_size<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_knows_ownership
      : detail::allocator_has_owns_impl<T>{};

    template<typename T>
    constexpr bool allocator_knows_ownership_v = allocator_knows_ownership<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_info
      : detail::allocator_has_info_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_info_v = allocator_has_info<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_is_unbounded
      : detail::allocator_has_is_unbounded_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_is_unbounded_v = allocator_has_is_unbounded<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_max_size
      : detail::allocator_has_max_size_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_max_size_v = allocator_has_max_size<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_min_size
      : detail::allocator_has_min_size_impl<T>{};

    template<typename T>
    constexpr bool allocator_has_min_size_v = allocator_has_min_size<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_default_alignment
      : detail::allocator_default_alignment_impl<T>{};

    template<typename T>
    constexpr allocator_size_type_t<T> allocator_default_alignment_v = allocator_default_alignment<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_max_alignment
      : detail::allocator_max_alignment_impl<T>{};

    template<typename T>
    constexpr allocator_size_type_t<T> allocator_max_alignment_v = allocator_max_alignment<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct allocator_has_expand
      : detail::allocator_has_expand<T>{};

    template<typename T>
    constexpr bool allocator_has_expand_v = allocator_has_expand<T>::value;

    //-------------------------------------------------------------------------

    template<typename T>
    struct is_allocator : std::integral_constant<bool,
      detail::allocator_has_try_allocate_impl<T>::value &&
      detail::allocator_has_deallocate_impl<T>::value
    >{};

    template<typename T>
    constexpr bool is_allocator_v = is_allocator<T>::value;

  } // namespace memory
} // namespace bit

#endif /* BIT_MEMORY_CONCEPTS_ALLOCATOR_HPP */