flash/flash.hpp

#pragma once

#include <cstddef>

#include <avr/pgmspace.h>

#define F(str) (reinterpret_cast<const ::detail::FlashString *>(PSTR(str)))
#define GF(name, str) \
	const char __##name[] PROGMEM = str; \
	const auto *name = reinterpret_cast<const ::detail::FlashString *>(__##name)

namespace detail {

// Only used for C++ type safety, because otherwise a PSTR would be indistinguishable from a normal c-string
struct FlashString;

} // namespace detail

namespace flash {

template <typename T>
static T load(const T &object)
{
	auto buffer = T{};
	auto rawBuffer = reinterpret_cast<std::byte *>(&buffer);
	for (auto i = std::size_t{0}; i < sizeof(T); ++i) {
		rawBuffer[i] = static_cast<std::byte>(pgm_read_byte(&reinterpret_cast<const std::byte *>(&object)[i]));
	}
	return buffer;
}

} // namespace flash