register.hpp

#ifndef SYSD_REGISTER_HPP
#define SYSD_REGISTER_HPP

#pragma once

#include <cstdint>
#include <type_traits>

#include "sysd/utility.hpp"

namespace sysd {
    template <typename T>
    using add_vptr_t = std::add_pointer_t<std::add_volatile_t<T>>;
    
    template <typename T,
              sysd::add_vptr_t<std::decay_t<T>> addr>
    struct reg {
        constexpr void set(T value) const noexcept {
            (*addr) = value;
        }

        constexpr T& get() const noexcept {
            return *addr;
        }

        template <std::uint8_t... bits>
        constexpr void set_bits() const noexcept {
            ((*addr |= bits), ...);
        }

        template <std::uint8_t... bits>
        constexpr void unset_bits() const noexcept {
            ((*addr &= ~bits), ...);
        }

        template <std::uint8_t... bits>
        constexpr void toggle_bits() const noexcept {
            ((*addr ^= bits), ...);
        }
    };

    // register aliases
    template <volatile std::uint8_t *addr>
    using register8 = reg<std::uint8_t, addr>;

    template <volatile std::uint_fast16_t *addr>
    using register16 = reg<std::uint_fast16_t, addr>;

    template <volatile std::uint_fast32_t *addr>
    using register32 = reg<std::uint_fast32_t, addr>;

    // register definitions
    constexpr sysd::register8<&P1IN>    port1_in{};
    constexpr sysd::register8<&P1OUT>   port1_out{};
    constexpr sysd::register8<&P1DIR>   port1_dir{};
    constexpr sysd::register16<&WDTCTL> watchdog_ctrl{};
   // ... continued definitions of memory-mapped registers
}

#endif /* SYSD_REGISTER_HPP */