bytes.inl
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#ifndef CRUCIBLE_PARSING_BYTES_INL
#define CRUCIBLE_PARSING_BYTES_INL
#include "crucible/parsing/bytes.hpp"
#include <climits>
namespace crucible::parsing::bytes {
template<UnsignedIntegerType T, Endianness E>
auto UnsignedInteger<T, E>::operator()(StateType const &initial_state) const -> ResultType {
auto const remaining_bytes { initial_state.get_remaining_input() };
if (remaining_bytes.size() < sizeof(T)) {
return errors::make_reject(initial_state, errors::InsufficientInput { sizeof(T) });
}
T total { 0 };
auto const shift_next_byte {
[](std::byte const next_byte, std::size_t const byte_index) {
std::size_t const bits_to_shift { byte_index * CHAR_BIT };
auto const byte_value { std::to_integer<T>(next_byte) };
return static_cast<T>(byte_value << bits_to_shift);
}
};
for (std::size_t i { 0 }; i < sizeof(T); ++i) {
if constexpr (E == Endianness::Le) {
total |= shift_next_byte(remaining_bytes[i], i);
} else {
total |= shift_next_byte(remaining_bytes[i], sizeof(T) - (i + 1));
}
}
auto const next_state { initial_state.advance(sizeof(T)) };
return errors::make_accept(next_state, total);
}
}
#endif // CRUCIBLE_PARSING_BYTES_INL