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//
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//
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// Copyright (c) 2025 Vinnie Falco (vinnie dot falco at gmail dot com)
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// Copyright (c) 2025 Vinnie Falco (vinnie dot falco at gmail dot com)
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//
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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//
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// Official repository: https://github.com/cppalliance/capy
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// Official repository: https://github.com/cppalliance/capy
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//
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//
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#ifndef BOOST_CAPY_DETAIL_FRAME_MEMORY_RESOURCE_HPP
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#ifndef BOOST_CAPY_DETAIL_FRAME_MEMORY_RESOURCE_HPP
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#define BOOST_CAPY_DETAIL_FRAME_MEMORY_RESOURCE_HPP
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#define BOOST_CAPY_DETAIL_FRAME_MEMORY_RESOURCE_HPP
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#include <boost/capy/detail/config.hpp>
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#include <boost/capy/detail/config.hpp>
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#include <cstddef>
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#include <cstddef>
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#include <memory>
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#include <memory>
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#include <memory_resource>
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#include <memory_resource>
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#include <type_traits>
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#include <type_traits>
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namespace boost {
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namespace boost {
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namespace capy {
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namespace capy {
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namespace detail {
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namespace detail {
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/** Wrapper that adapts a standard Allocator to memory_resource.
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/** Wrapper that adapts a standard Allocator to memory_resource.
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    This wrapper is used to store value-type allocators in the
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    This wrapper is used to store value-type allocators in the
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    execution context or trampoline frame. It rebinds the allocator
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    execution context or trampoline frame. It rebinds the allocator
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    to std::byte for raw memory allocation.
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    to std::byte for raw memory allocation.
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    @tparam Alloc The standard allocator type.
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    @tparam Alloc The standard allocator type.
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*/
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*/
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template<class Alloc>
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template<class Alloc>
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class frame_memory_resource : public std::pmr::memory_resource
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class frame_memory_resource : public std::pmr::memory_resource
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{
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{
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    using traits = std::allocator_traits<Alloc>;
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    using traits = std::allocator_traits<Alloc>;
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    using byte_alloc = typename traits::template rebind_alloc<std::byte>;
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    using byte_alloc = typename traits::template rebind_alloc<std::byte>;
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    using byte_traits = std::allocator_traits<byte_alloc>;
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    using byte_traits = std::allocator_traits<byte_alloc>;
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    static_assert(
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    static_assert(
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        requires { typename traits::value_type; },
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        requires { typename traits::value_type; },
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        "Alloc must satisfy allocator requirements");
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        "Alloc must satisfy allocator requirements");
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    static_assert(
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    static_assert(
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        std::is_copy_constructible_v<Alloc>,
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        std::is_copy_constructible_v<Alloc>,
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        "Alloc must be copy constructible");
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        "Alloc must be copy constructible");
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    byte_alloc alloc_;
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    byte_alloc alloc_;
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public:
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public:
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    /** Construct from an allocator.
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    /** Construct from an allocator.
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        The allocator is rebind-copied to std::byte.
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        The allocator is rebind-copied to std::byte.
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        @param a The allocator to adapt.
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        @param a The allocator to adapt.
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    */
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    */
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    explicit
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    explicit
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    frame_memory_resource(Alloc const& a)
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    frame_memory_resource(Alloc const& a)
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        : alloc_(a)
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        : alloc_(a)
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    {
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    {
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    }
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    }
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    /** Get the memory resource pointer.
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    /** Get the memory resource pointer.
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        @return Pointer to this memory resource.
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        @return Pointer to this memory resource.
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    */
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    */
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    std::pmr::memory_resource* get() noexcept { return this; }
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    std::pmr::memory_resource* get() noexcept { return this; }
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protected:
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protected:
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    void*
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    void*
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    do_allocate(std::size_t bytes, std::size_t) override
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    do_allocate(std::size_t bytes, std::size_t) override
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    {
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    {
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        return byte_traits::allocate(alloc_, bytes);
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        return byte_traits::allocate(alloc_, bytes);
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    }
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    }
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    void
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    void
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    do_deallocate(void* p, std::size_t bytes, std::size_t) override
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    do_deallocate(void* p, std::size_t bytes, std::size_t) override
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    {
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    {
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        byte_traits::deallocate(alloc_, static_cast<std::byte*>(p), bytes);
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        byte_traits::deallocate(alloc_, static_cast<std::byte*>(p), bytes);
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    }
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    }
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    bool
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    bool
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    do_is_equal(const memory_resource& other) const noexcept override
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    do_is_equal(const memory_resource& other) const noexcept override
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    {
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    {
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        return this == &other;
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        return this == &other;
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    }
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    }
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};
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};
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} // namespace detail
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} // namespace detail
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} // namespace capy
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} // namespace capy
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} // namespace boost
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} // namespace boost
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#endif
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#endif