golang에서는 비트 구조체 안되던것 같은데 러스트에서는 된다고 하니 관심이 증가중 ㅋㅋ
머 리눅스 커널에서도 쓰려고 하는데 설마 없겠어? 싶기도 하네
use bit_struct::*;
enums! {
// 2 bits, i.e., 0b00, 0b01, 0b10
pub HouseKind { Urban, Suburban, Rural}
}
bit_struct! {
// u8 is the base storage type. This can be any multiple of 8
pub struct HouseConfig(u8) {
// 2 bits
kind: HouseKind,
// two's compliment 3-bit signed number
lowest_floor: i3,
// 2 bit unsigned number
highest_floor: u2,
}
}
// We can create a new `HouseConfig` like such:
// where all numbers are statically checked to be in bounds.
let config = HouseConfig::new(HouseKind::Suburban, i3!(-2), u2!(1));
// We can get the raw `u8` which represents `config`:
let raw: u8 = config.raw();
assert_eq!(114_u8, raw);
// or we can get a `HouseConfig` from a `u8` like:
let mut config: HouseConfig = HouseConfig::try_from(114_u8).unwrap();
assert_eq!(config, HouseConfig::new(HouseKind::Suburban, i3!(-2), u2!(1)));
// We need to unwrap because `HouseConfig` is not valid for all numbers. For instance, if the
// most significant bits are `0b11`, it encodes an invalid `HouseKind`. However,
// if all elements of a struct are always valid (suppose we removed the `kind` field), the struct will
// auto implement a trait which allows calling the non-panicking:
// let config: HouseConfig = HouseConfig::exact_from(123_u8);
// We can access values of `config` like so:
let kind: HouseKind = config.kind().get();
// And we can set values like so:
config.lowest_floor().set(i3!(0));
// We can also convert the new numeric types for alternate bit-widths into the
// numeric types provided by the standard library:
let lowest_floor: i3 = config.lowest_floor().get();
let lowest_floor_std: i8 = lowest_floor.value();
assert_eq!(lowest_floor_std, 0_i8);
[링크 : https://docs.rs/bit-struct/latest/bit_struct/]
