Files
rosenpass/util/src/mem.rs
2023-11-26 10:38:24 +01:00

34 lines
1.0 KiB
Rust

use std::borrow::{Borrow, BorrowMut};
use std::cmp::min;
/// Concatenate two byte arrays
// TODO: Zeroize result?
#[macro_export]
macro_rules! cat {
($len:expr; $($toks:expr),+) => {{
let mut buf = [0u8; $len];
let mut off = 0;
$({
let tok = $toks;
let tr = ::std::borrow::Borrow::<[u8]>::borrow(tok);
(&mut buf[off..(off + tr.len())]).copy_from_slice(tr);
off += tr.len();
})+
assert!(off == buf.len(), "Size mismatch in cat!()");
buf
}}
}
// TODO: consistent inout ordering
pub fn cpy<T: BorrowMut<[u8]> + ?Sized, F: Borrow<[u8]> + ?Sized>(src: &F, dst: &mut T) {
dst.borrow_mut().copy_from_slice(src.borrow());
}
/// Copy from `src` to `dst`. If `src` and `dst` are not of equal length, copy as many bytes as possible.
pub fn cpy_min<T: BorrowMut<[u8]> + ?Sized, F: Borrow<[u8]> + ?Sized>(src: &F, dst: &mut T) {
let src = src.borrow();
let dst = dst.borrow_mut();
let len = min(src.len(), dst.len());
dst[..len].copy_from_slice(&src[..len]);
}