multiboot2: rearrange project structure

9 files changed, 0 insertions, 956 deletions

diff --git a/libs/multiboot2/include/multiboot2/constants.hpp b/libs/multiboot2/include/multiboot2/constants.hpp
deleted file mode 100644
index 2198210..0000000
--- a/libs/multiboot2/include/multiboot2/constants.hpp
+++ /dev/null
@@ -1,15 +0,0 @@
-#ifndef MULTIBOOT2_CONSTANTS_HPP
-#define MULTIBOOT2_CONSTANTS_HPP
-
-#include "constants/architecture_id.hpp"  // IWYU pragma: export
-
-#include <cstdint>
-
-namespace multiboot2
-{
-
-  constexpr auto inline header_magic = std::uint32_t{0xe852'50d6};
-
-}  // namespace multiboot2
-
-#endif
diff --git a/libs/multiboot2/include/multiboot2/constants/architecture_id.hpp b/libs/multiboot2/include/multiboot2/constants/architecture_id.hpp
deleted file mode 100644
index e13c471..0000000
--- a/libs/multiboot2/include/multiboot2/constants/architecture_id.hpp
+++ /dev/null
@@ -1,22 +0,0 @@
-#ifndef MULTIBOOT2_CONSTANTS_ARCHITECTURE_ID_HPP
-#define MULTIBOOT2_CONSTANTS_ARCHITECTURE_ID_HPP
-
-// IWYU pragma: private, include <multiboot2/constants.hpp>
-
-#include <cstdint>
-
-namespace multiboot2
-{
-
-  //! The IDs of the supported system architectures.
-  enum struct architecture_id : std::uint32_t
-  {
-    //! 32-bit protected mode i386
-    i386 = 0,
-    //! 32-bit MIPS
-    mips32 = 4,
-  };
-
-}  // namespace multiboot2
-
-#endif
\ No newline at end of file
diff --git a/libs/multiboot2/include/multiboot2/constants/information_id.hpp b/libs/multiboot2/include/multiboot2/constants/information_id.hpp
deleted file mode 100644
index 27c5300..0000000
--- a/libs/multiboot2/include/multiboot2/constants/information_id.hpp
+++ /dev/null
@@ -1,86 +0,0 @@
-#ifndef MULTIBOOT2_CONSTANTS_INFORMATION_ID_HPP
-#define MULTIBOOT2_CONSTANTS_INFORMATION_ID_HPP
-
-// IWYU pragma: private, include <multiboot2/constants.hpp>
-
-#include <cstdint>
-
-namespace multiboot2
-{
-
-  //! The IDs of all Multiboot2 information tags.
-  //!
-  //! Each tag provided by the boot loader will be tagged with one of these IDs. A tags data format can thus be deduced
-  //! from it's ID.
-  enum struct information_id : std::uint32_t
-  {
-    //! Signals final tag for the multiboot2 information structure.
-    end,
-
-    //! The command line string.
-    command_line,
-
-    //! The name of the boot loader booting the kernel.
-    boot_loader_name,
-
-    //! Indicates the boot module which was loaded along the kernel image.
-    module,
-
-    //! The amount of lower and upper (above 1 MiB) memory.
-    basic_memory_information,
-
-    //! Indicates which BIOS disk device the hoot loader has loaded the OS image from.
-    boot_device,
-
-    //! Describes the memory layout of the system with individual areas and their flags.
-    memory_map,
-
-    //! Includes information to access and utilize the device GPU.
-    vbe_information,
-
-    //! VBE framebuffer information.
-    framebuferr_information,
-
-    //! Includes list of all section headers from the loaded ELF kernel.
-    elf_sections,
-
-    //! Advanced Power Management information.
-    apm_information,
-
-    //! The pointer to the EFI 32 bit system table.
-    efi32_system_table_pointer,
-
-    //! The pointer to the EFI 64 bit system table.
-    efi64_system_table_pointer,
-
-    //! A copy of all System Management BIOS tables.
-    smbios_tables,
-
-    //! A copy of RSDP as defined per ACPI 1.0 specification.
-    acpi_rsdp,
-
-    //! A copy of XSDP as defined per ACPI 2.0 or later specification.
-    acpi_xsdp,
-
-    //! The network information specified specified as per DHCP.
-    networking_information,
-
-    //! The memory map as provided by the EFI.
-    efi_memory_map,
-
-    //! Indicates ExitBootServices wasn't called.
-    boot_services_not_terminated,
-
-    //! EFI 32 bit image handle pointer.
-    efi32_image_handle_pointer,
-
-    //! EFI 64 bit image handle pointer.
-    efi64_image_handle_pointer,
-
-    //! The physical image load base address.
-    image_load_base_address
-  };
-
-}  // namespace multiboot2
-
-#endif
diff --git a/libs/multiboot2/include/multiboot2/constants/memory_type.hpp b/libs/multiboot2/include/multiboot2/constants/memory_type.hpp
deleted file mode 100644
index 6be94bd..0000000
--- a/libs/multiboot2/include/multiboot2/constants/memory_type.hpp
+++ /dev/null
@@ -1,33 +0,0 @@
-#ifndef MULTIBOOT2_CONSTANTS_MEMORY_TYPE_HPP
-#define MULTIBOOT2_CONSTANTS_MEMORY_TYPE_HPP
-
-// IWYU pragma: private, include <multiboot2/constants.hpp>
-
-#include <cstdint>
-
-namespace multiboot2
-{
-
-  //! The types of memory potentially present in the detailed memory map.
-  enum struct memory_type : std::uint32_t
-  {
-    //! The memory is available for general use by the operating system.
-    available = 1,
-
-    //! The memory is reserved for firmware or other purposes and must not be used for general purposes by the operating
-    //! system.
-    reserved,
-
-    //! The memory contains ACPI data and can be reclaimed when ACPI is not in use.
-    acpi_reclaimable,
-
-    //! The memory is reserved for non-volatile storage.
-    non_volatile_storage,
-
-    //! The memory range is occupied by defective RAM.
-    bad_ram,
-  };
-
-}  // namespace multiboot2
-
-#endif
\ No newline at end of file
diff --git a/libs/multiboot2/include/multiboot2/constants/tag_id.hpp b/libs/multiboot2/include/multiboot2/constants/tag_id.hpp
deleted file mode 100644
index 23d39cc..0000000
--- a/libs/multiboot2/include/multiboot2/constants/tag_id.hpp
+++ /dev/null
@@ -1,29 +0,0 @@
-#ifndef MULTIBOOT2_CONSTANTS_TAG_ID_HPP
-#define MULTIBOOT2_CONSTANTS_TAG_ID_HPP
-
-// IWYU pragma: private, include <multiboot2/constants.hpp>
-
-#include <cstdint>
-
-namespace multiboot2
-{
-
-  //! The IDs for tags to be used in the image header.
-  enum struct tag_id : std::uint32_t
-  {
-    end,
-    information_request,
-    addresses,
-    entry_address,
-    console_flags,
-    preferred_framebuffer_mode,
-    page_align_modules,
-    efi_boot_services_supported,
-    efi32_entry_address,
-    efi64_entry_address,
-    relocatable_image,
-  };
-
-}  // namespace multiboot2
-
-#endif
\ No newline at end of file
diff --git a/libs/multiboot2/include/multiboot2/information.hpp b/libs/multiboot2/include/multiboot2/information.hpp
deleted file mode 100644
index a2ded56..0000000
--- a/libs/multiboot2/include/multiboot2/information.hpp
+++ /dev/null
@@ -1,308 +0,0 @@
-#ifndef MULTIBOOT2_INFORMATION_HPP
-#define MULTIBOOT2_INFORMATION_HPP
-
-#include "information/data.hpp"      // IWYU pragma: export
-#include "information/iterator.hpp"  // IWYU pragma: export
-#include "information/tag.hpp"       // IWYU pragma: export
-
-#include <kstd/units>
-
-#include <elf/format.hpp>
-#include <elf/section_header.hpp>
-
-#include <algorithm>
-#include <cstddef>
-#include <cstdint>
-#include <cstdlib>
-#include <optional>
-#include <ranges>
-#include <span>
-#include <string_view>
-
-namespace multiboot2
-{
-
-  /**
-   * @copydoc multiboot2::data::basic_memory
-   */
-  struct basic_memory : tag<data::basic_memory>
-  {
-    using tag::tag;
-  };
-
-  /**
-   * @copydoc multiboot2::data::bios_boot_device
-   */
-  struct bios_boot_device : tag<data::bios_boot_device>
-  {
-    using tag::tag;
-  };
-
-  /**
-   * @copydoc multiboot2::data::command_line
-   */
-  struct command_line : vla_tag<data::command_line, char, std::basic_string_view>
-  {
-    using vla_tag::vla_tag;
-
-    /**
-     * @brief The command line string
-     */
-    [[nodiscard]] auto string() const noexcept -> range_type
-    {
-      return {data(), size()};
-    }
-  };
-
-  /**
-   * @copydoc multiboot2::data::elf_symbols
-   */
-  template<elf::format Format>
-  struct elf_symbols : vla_tag<data::elf_symbols, elf::section_header<Format> const, std::span>
-  {
-    using base = vla_tag<data::elf_symbols, elf::section_header<Format> const, std::span>;
-    using base::base;
-
-    [[nodiscard]] auto name(elf::section_header<Format> const & section) const noexcept -> std::string_view
-    {
-      if (!this->string_table_index)
-      {
-        std::abort();
-      }
-
-      auto string_table = this->begin()[this->string_table_index];
-      auto name_offset = section.name_offset;
-      auto name_array = std::bit_cast<char const *>(string_table.virtual_load_address);
-      return name_array + name_offset;
-    }
-  };
-
-  /**
-   * @copydoc multiboot2::data::loader_name
-   */
-  struct loader_name : vla_tag<data::loader_name, char, std::basic_string_view>
-  {
-    using vla_tag::vla_tag;
-
-    /**
-     * @brief The name of the bootloader
-     */
-    [[nodiscard]] auto string() const noexcept -> std::string_view
-    {
-      return {data(), size()};
-    }
-  };
-
-  /**
-   * @copydoc multiboot2::data::memory_map
-   */
-  struct memory_map : vla_tag<data::memory_map, data::memory_map::region, std::span>
-  {
-    using vla_tag::vla_tag;
-
-    /**
-     * @brief The available memory regions
-     */
-    [[nodiscard]] auto regions() const noexcept -> range_type
-    {
-      return {data(), size()};
-    }
-  };
-
-  /**
-   * @copydoc multiboot2::data::module
-   */
-  struct module : vla_tag<data::module, char, std::basic_string_view>
-  {
-    using vla_tag::vla_tag;
-
-    /**
-     * @brief The module command line or name.
-     */
-    [[nodiscard]] auto string() const noexcept -> std::string_view
-    {
-      return {data(), vla_tag::size()};
-    }
-
-    [[nodiscard]] constexpr auto size() const noexcept -> kstd::units::bytes
-    {
-      return kstd::units::bytes{end_address - start_address};
-    }
-  };
-  
-  struct acpi_rsdp : vla_tag<data::acpi_rsdp, std::byte, std::span>
-  {
-    using vla_tag::vla_tag;
-
-    [[nodiscard]] auto pointer() const noexcept -> range_type
-    {
-      return {data(), size()};
-    }
-  };
-
-  struct acpi_xsdp : vla_tag<data::acpi_xsdp, std::byte, std::span>
-  {
-    using vla_tag::vla_tag;
-
-    [[nodiscard]] auto pointer() const noexcept -> range_type
-    {
-      return {data(), size()};
-    }
-  };
-
-  struct information_view
-  {
-    using iterator = iterator;
-    using value_type = iterator::value_type;
-    using pointer = iterator::pointer;
-    using reference = iterator::reference;
-
-    [[nodiscard]] auto size() const noexcept -> kstd::units::bytes
-    {
-      return kstd::units::bytes{m_size};
-    }
-
-    // Range access
-
-    [[nodiscard]] auto begin() const noexcept -> iterator
-    {
-      return iterator{&m_tags};
-    }
-
-    [[nodiscard]] auto end() const noexcept -> iterator
-    {
-      return iterator{};
-    }
-
-    // Tag access
-
-    template<typename Tag>
-    [[nodiscard]] auto has() const noexcept -> bool
-    {
-      return get<Tag>().has_value();
-    }
-
-    [[nodiscard]] auto maybe_basic_memory() const noexcept -> std::optional<basic_memory>
-    {
-      return get<multiboot2::basic_memory>();
-    }
-
-    [[nodiscard]] auto basic_memory() const -> basic_memory
-    {
-      return maybe_basic_memory().value();
-    }
-
-    [[nodiscard]] auto maybe_bios_boot_device() const noexcept -> std::optional<bios_boot_device>
-    {
-      return get<multiboot2::bios_boot_device>();
-    }
-
-    [[nodiscard]] auto bios_boot_device() const -> bios_boot_device
-    {
-      return maybe_bios_boot_device().value();
-    }
-
-    [[nodiscard]] auto maybe_command_line() const noexcept -> std::optional<command_line>
-    {
-      return get<multiboot2::command_line>();
-    }
-
-    [[nodiscard]] auto command_line() const -> command_line
-    {
-      return maybe_command_line().value();
-    }
-
-    template<elf::format Format>
-    [[nodiscard]] auto maybe_elf_symbols() const noexcept -> std::optional<elf_symbols<Format>>
-    {
-      return get<multiboot2::elf_symbols<Format>>().and_then(
-          [](auto x) -> std::optional<multiboot2::elf_symbols<Format>> {
-            if (x.entry_size_in_B == elf::section_header_size<Format>)
-            {
-              return std::optional{x};
-            }
-            else
-            {
-              return std::nullopt;
-            }
-          });
-    }
-
-    template<elf::format Format>
-    [[nodiscard]] auto elf_symbols() const -> elf_symbols<Format>
-    {
-      return maybe_elf_symbols<Format>().value();
-    }
-
-    [[nodiscard]] auto maybe_loader_name() const noexcept -> std::optional<loader_name>
-    {
-      return get<multiboot2::loader_name>();
-    }
-
-    [[nodiscard]] auto loader_name() const -> loader_name
-    {
-      return maybe_loader_name().value();
-    }
-
-    [[nodiscard]] auto maybe_memory_map() const noexcept -> std::optional<memory_map>
-    {
-      return get<multiboot2::memory_map>();
-    }
-
-    [[nodiscard]] auto memory_map() const -> memory_map
-    {
-      return maybe_memory_map().value();
-    }
-
-    [[nodiscard]] auto modules() const noexcept
-    {
-      auto filter_modules = [](auto const & tag) {
-        return tag.information_id() == module::id;
-      };
-      auto transform_module = [](auto const & tag) {
-        return module{&tag};
-      };
-      return std::ranges::subrange(begin(), end()) | std::views::filter(filter_modules) |
-             std::views::transform(transform_module);
-    }
-
-    [[nodiscard]] auto maybe_acpi_rsdp() const noexcept -> std::optional<acpi_rsdp>
-    {
-      return get<multiboot2::acpi_rsdp>();
-    }
-
-    [[nodiscard]] auto acpi_rsdp() const noexcept -> acpi_rsdp
-    {
-      return maybe_acpi_rsdp().value();
-    }
-
-    [[nodiscard]] auto maybe_acpi_xsdp() const noexcept -> std::optional<acpi_xsdp>
-    {
-      return get<multiboot2::acpi_xsdp>();
-    }
-
-    [[nodiscard]] auto acpi_xsdp() const noexcept -> acpi_xsdp
-    {
-      return maybe_acpi_xsdp().value();
-    }
-
-  private:
-    template<typename Tag>
-    [[nodiscard]] constexpr auto get() const noexcept -> std::optional<Tag>
-    {
-      if (auto found = std::ranges::find_if(*this, [](auto tag) { return tag.information_id() == Tag::id; });
-          found != end())
-      {
-        return Tag{&*found};
-      }
-      return std::nullopt;
-    }
-
-    uint32_t m_size{};
-    uint32_t : 32;
-    tag_header m_tags{};
-  };
-
-}  // namespace multiboot2
-
-#endif
diff --git a/libs/multiboot2/include/multiboot2/information/data.hpp b/libs/multiboot2/include/multiboot2/information/data.hpp
deleted file mode 100644
index 315eb39..0000000
--- a/libs/multiboot2/include/multiboot2/information/data.hpp
+++ /dev/null
@@ -1,184 +0,0 @@
-#ifndef MULTIBOOT2_INFORMATION_DATA_HPP
-#define MULTIBOOT2_INFORMATION_DATA_HPP
-
-// IWYU pragma: private, include <multiboot2/information.hpp>
-
-#include "multiboot2/constants/information_id.hpp"
-#include "multiboot2/constants/memory_type.hpp"
-
-#include <kstd/units>
-
-#include <cstdint>
-
-namespace multiboot2
-{
-  //! A simple base mixin providing all data classes with an ID accessor.
-  template<auto Id>
-  struct tag_data
-  {
-    //! The ID of this data class.
-    constexpr auto static inline id = Id;
-  };
-
-  namespace data
-  {
-
-    //! Basic system memory information
-    //!
-    //! This tag contains the amount of lower memory and upper memory present in the system as detected by the boot
-    //! loader.
-    struct basic_memory : tag_data<information_id::basic_memory_information>
-    {
-      [[nodiscard]] constexpr auto lower() const noexcept -> kstd::units::bytes
-      {
-        return kstd::units::bytes{lower_KiB * 1024};
-      }
-
-      [[nodiscard]] constexpr auto upper() const noexcept -> kstd::units::bytes
-      {
-        return kstd::units::bytes{upper_KiB * 1024};
-      }
-
-      //! The amount of lower memory available to the system.
-      //!
-      //! Any memory below the 1 MiB address boundary is considered to be lower memory. The maximum possible value for
-      //! this field is 640 KiB.
-      std::uint32_t lower_KiB;
-
-      //! The amount of upper memory available to the system.
-      //!
-      //! Any memory above the 1 MiB address boundary is considered to be upper memory. The maximum possible value for
-      //! this field is the address of the first upper memory hole minus 1MiB.
-      std::uint32_t upper_KiB;
-    };
-
-    //! The BIOS disk the image got loaded from
-    //!
-    //! This tag is present iff. the image was loaded from a BIOS disk device.
-    struct bios_boot_device : tag_data<information_id::boot_device>
-    {
-      //! BIOS device number the image was loaded from, as understood by INT 13h.
-      //!
-      //! For example, the first floppy drive will receive id 0x00, while the first hard disk will receive id 0x80.
-      std::uint32_t device_number;
-
-      //! The partition number of the primary partition the image was loaded from.
-      std::uint32_t partition_number;
-
-      //! The sub-partition number of the primary partition the image was loaded from.
-      std::uint32_t sub_partition_number;
-    };
-
-    //! The command line supplied to the image during boot.
-    //!
-    //! @note This structure is intentionally left blank, since it is of variable size and the contained information
-    //! starts at the first byte of this structure.
-    struct command_line : tag_data<information_id::command_line>
-    {
-    };
-
-    //! The ELF sections of the image.
-    //!
-    //! @note The actual section header array is not part of this type's definition. The reason being that the size of
-    //! the array, in terms of entry count, as well as the size and format of each array element is unknown at compile
-    //! time. The array begins after the last member of this structure.
-    struct elf_symbols : tag_data<information_id::elf_sections>
-    {
-      [[nodiscard]] constexpr auto entry_size() const noexcept -> kstd::units::bytes
-      {
-        return kstd::units::bytes{entry_size_in_B};
-      }
-
-      //! The number of section header table entries.
-      std::uint32_t count;
-
-      //! The size of each section header table entry.
-      std::uint32_t entry_size_in_B;
-
-      //! The section number of the string table containing the section names.
-      std::uint32_t string_table_index;
-    };
-
-    //! The name of the boot loader that loaded the image.
-    //!
-    //! @note This structure is intentionally left blank, since it is of variable size and the contained information
-    //! starts at the first byte of this structure.
-    struct loader_name : tag_data<information_id::boot_loader_name>
-    {
-    };
-
-    //! The detailed memory map of this system.
-    struct memory_map : tag_data<information_id::memory_map>
-    {
-      //! A single region of memory
-      struct region
-      {
-        //! Check if the memory described by this region is available for use.
-        [[nodiscard]] constexpr auto available() const noexcept
-        {
-          return type == memory_type::available;
-        }
-
-        [[nodiscard]] constexpr auto size() const noexcept -> kstd::units::bytes
-        {
-          return kstd::units::bytes{size_in_B};
-        }
-
-        //! The physical start address of this region
-        std::uint64_t base;
-
-        //! The size of this region in bytes.
-        std::uint64_t size_in_B;
-
-        //! The type of this region.
-        //!
-        //! @see multiboot::memory_types
-        memory_type type;
-
-        //! This field is reserved for padding and use in future extensions.
-        std::uint32_t : 0;
-      };
-
-      [[nodiscard]] constexpr auto entry_size() const noexcept -> kstd::units::bytes
-      {
-        return kstd::units::bytes{entry_size_in_B};
-      }
-
-      //! The size of each entry present in the map.
-      //!
-      //! This field is present to allow for future extension of the entry format. Each entry's size is guaranteed to
-      //! always be an integer multiple of 8.
-      std::uint32_t entry_size_in_B;
-
-      //! The version of each entry present in the map
-      std::uint32_t entry_version;
-    };
-
-    //! A module loaded by the bootloader.
-    //!
-    //! @note the command line associated with this module is not part of this structure, since it is of variable size
-    //! and the contained information starts at the end of this structure.
-    struct module : tag_data<information_id::module>
-    {
-      //! The physical start address of this module.
-      std::uint32_t start_address;
-
-      //! The physical end address of this module.
-      std::uint32_t end_address;
-    };
-
-    //! A copy of the ACPI RSDP
-    struct acpi_rsdp : tag_data<information_id::acpi_rsdp>
-    {
-    };
-
-    //! A copy of the ACPI XSDP
-    struct acpi_xsdp : tag_data<information_id::acpi_xsdp>
-    {
-    };
-
-  }  // namespace data
-
-}  // namespace multiboot2
-
-#endif
diff --git a/libs/multiboot2/include/multiboot2/information/iterator.hpp b/libs/multiboot2/include/multiboot2/information/iterator.hpp
deleted file mode 100644
index 62c267d..0000000
--- a/libs/multiboot2/include/multiboot2/information/iterator.hpp
+++ /dev/null
@@ -1,73 +0,0 @@
-#ifndef MULTIBOOT2_INFORMATION_ITERATOR_HPP
-#define MULTIBOOT2_INFORMATION_ITERATOR_HPP
-
-// IWYU pragma: private, include <multiboot2/information.hpp>
-
-#include "multiboot2/constants/information_id.hpp"
-#include "tag.hpp"
-
-#include <cstddef>
-#include <iterator>
-#include <optional>
-
-namespace multiboot2
-{
-
-  struct iterator
-  {
-    using iterator_category = std::forward_iterator_tag;
-    using value_type = tag_header;
-    using pointer = value_type const *;
-    using reference = value_type const &;
-    using difference_type = std::ptrdiff_t;
-
-    constexpr iterator() = default;
-
-    constexpr explicit iterator(tag_header const * offset)
-        : m_current(offset)
-    {}
-
-    constexpr auto operator==(iterator const &) const noexcept -> bool = default;
-
-    constexpr auto operator*() const noexcept -> reference
-    {
-      return *(m_current.value());
-    }
-
-    constexpr auto operator->() const noexcept -> pointer
-    {
-      return m_current.value();
-    }
-
-    constexpr auto operator++() noexcept -> iterator &
-    {
-      if (m_current)
-      {
-        if (auto next = m_current.value()->next(); next->information_id() != information_id::end)
-        {
-          m_current = next;
-        }
-        else
-        {
-          m_current.reset();
-        }
-      }
-      return *this;
-    }
-
-    constexpr auto operator++(int) noexcept -> iterator
-    {
-      auto copy = *this;
-      ++(*this);
-      return copy;
-    }
-
-  private:
-    std::optional<tag_header const *> m_current{};
-  };
-
-  static_assert(std::input_or_output_iterator<iterator>);
-
-}  // namespace multiboot2
-
-#endif
\ No newline at end of file
diff --git a/libs/multiboot2/include/multiboot2/information/tag.hpp b/libs/multiboot2/include/multiboot2/information/tag.hpp
deleted file mode 100644
index 8d90790..0000000
--- a/libs/multiboot2/include/multiboot2/information/tag.hpp
+++ /dev/null
@@ -1,206 +0,0 @@
-#ifndef MULTIBOOT2_INFORMATION_TAG_HPP
-#define MULTIBOOT2_INFORMATION_TAG_HPP
-
-// IWYU pragma: private, include <multiboot2/information.hpp>
-
-#include "multiboot2/constants/information_id.hpp"
-
-#include <bit>
-#include <cstddef>
-#include <cstdint>
-#include <string_view>
-
-namespace multiboot2
-{
-
-  /**
-   * @brief Header data and functionality shared by all tags.
-   */
-  struct tag_header
-  {
-    tag_header()
-        : m_id{}
-        , m_size{}
-    {}
-
-    tag_header(tag_header const * data)
-        : tag_header{*data}
-    {}
-
-    [[nodiscard]] auto full_size() const noexcept -> std::size_t
-    {
-      return (m_size + 7) & (~7);
-    }
-
-    [[nodiscard]] auto information_id() const noexcept -> information_id const &
-    {
-      return m_id;
-    }
-
-    [[nodiscard]] auto next() const noexcept -> tag_header const *
-    {
-      return std::bit_cast<tag_header const *>(std::bit_cast<std::uintptr_t>(this) + full_size());
-    }
-
-    [[nodiscard]] auto unaligned_size() const noexcept -> std::uint32_t
-    {
-      return m_size;
-    }
-
-  private:
-    enum information_id m_id;
-    std::uint32_t m_size;
-  };
-
-  /**
-   * @brief A tag containing no variable length array data.
-   */
-  template<typename Data>
-  struct tag : tag_header, Data
-  {
-    tag()
-        : tag_header{}
-        , Data{}
-    {}
-
-    explicit tag(tag_header const * header)
-      requires(sizeof(tag) > sizeof(tag_header))
-        : tag_header{header}
-        , Data{*std::bit_cast<Data const *>(header + 1)}
-    {}
-
-    explicit tag(tag_header const * header)
-      requires(sizeof(tag) == sizeof(tag_header))
-        : tag_header{header}
-        , Data{}
-    {}
-  };
-
-  /**
-   * @brief A tag containing variable length array data.
-   */
-  template<typename Data, typename VlaData, template<typename> typename Range>
-  struct vla_tag : tag<Data>
-  {
-    using range_type = Range<VlaData const>;
-
-    using value_type = range_type::value_type;
-    using reference = range_type::const_reference;
-    using const_reference = range_type::const_reference;
-    using pointer = range_type::const_pointer;
-    using const_pointer = range_type::const_pointer;
-
-    using iterator = range_type::const_iterator;
-    using const_iterator = range_type::const_iterator;
-    using reverse_iterator = range_type::const_reverse_iterator;
-    using const_reverse_iterator = range_type::const_reverse_iterator;
-    using size_type = range_type::size_type;
-    using difference_type = range_type::difference_type;
-
-    vla_tag()
-        : tag<Data>{}
-        , m_vla{}
-    {}
-
-    explicit vla_tag(tag_header const * header)
-        : tag<Data>{header}
-        , m_vla{vla_start(header), vla_size(header)}
-    {}
-
-    [[nodiscard]] auto begin() const noexcept -> const_iterator
-    {
-      return m_vla.begin();
-    }
-
-    [[nodiscard]] auto end() const noexcept -> const_iterator
-    {
-      return m_vla.end();
-    }
-
-    [[nodiscard]] auto cbegin() const noexcept -> const_iterator
-    {
-      return begin();
-    }
-
-    [[nodiscard]] auto cend() const noexcept -> const_iterator
-    {
-      return end();
-    }
-
-    [[nodiscard]] auto rbegin() const noexcept -> const_reverse_iterator
-    {
-      return m_vla.rbegin();
-    }
-
-    [[nodiscard]] auto rend() const noexcept -> const_reverse_iterator
-    {
-      return m_vla.rend();
-    }
-
-    [[nodiscard]] auto crbegin() const noexcept -> const_reverse_iterator
-    {
-      return rbegin();
-    }
-
-    [[nodiscard]] auto crend() const noexcept -> const_reverse_iterator
-    {
-      return rend();
-    }
-
-    [[nodiscard]] auto front() const noexcept -> const_reference
-    {
-      return m_vla.front();
-    }
-
-    [[nodiscard]] auto back() const noexcept -> const_reference
-    {
-      return m_vla.back();
-    }
-
-    [[nodiscard]] auto size() const noexcept -> std::size_t
-    {
-      return m_vla.size();
-    }
-
-    [[nodiscard]] auto empty() const noexcept -> bool
-    {
-      return m_vla.empty();
-    }
-
-    [[nodiscard]] auto data() const noexcept -> const_pointer
-    {
-      return m_vla.data();
-    }
-
-    [[nodiscard]] auto at(std::size_t index) const -> const_reference
-    {
-      return m_vla.at(index);
-    }
-
-    [[nodiscard]] auto operator[](std::size_t index) const noexcept -> const_reference
-    {
-      return m_vla[index];
-    }
-
-  private:
-    auto static vla_start(tag_header const * header) noexcept -> VlaData *
-    {
-      auto raw = std::bit_cast<std::uintptr_t>(header);
-      auto start = raw + sizeof(tag<Data>);
-      return std::bit_cast<VlaData *>(start);
-    }
-
-    auto static vla_size(tag_header const * header) noexcept -> std::size_t
-    {
-      auto size = (header->unaligned_size() - sizeof(tag<Data>) -
-                   std::is_same_v<range_type, std::basic_string_view<VlaData>> * 1) /
-                  sizeof(VlaData);
-      return size;
-    }
-
-    range_type m_vla;
-  };
-
-}  // namespace multiboot2
-
-#endif
\ No newline at end of file