Rust hex dumping

hex_dump.rs

const CHUNK_SIZE: usize = 0x10;
const NUMBERING_HEX: &str = "00 01 02 03 04 05 06 07  08 09 0A 0B 0C 0D 0E 0F ";
const NUMBERING_SEP: &str = "│";
const NUMBERING_ASCII: &str = " 0123456789ABCDEF";

fn hex_num_len(val: usize) -> usize {
    ((val as f64).log2() / (0x10 as f64).log2()) as usize + 1
}

fn to_ascii_dots(x: u8) -> char {
    match x {
        0..=0x1F | 0x7F..=0xA0 | 0xAD => '.',
        x => x as char,
    }
}

fn dump_hex_line((line, addr): (&[u8], usize)) {
    print!("{:08X}", addr);
    line.chunks(8)
        .for_each(|half|{
            print!(" ");
            half.iter()
                .for_each(|x| print!("{:02X} ", x))
        });
    print!("│ ");
    line.iter().for_each(|&x| print!("{}", to_ascii_dots(x)));
    println!();
}

fn hex_dump<T>(addr: *const T) {
    let addr = addr as usize;
    let aligned_addr = addr & !0xF;
    let start = aligned_addr.saturating_sub(CHUNK_SIZE * 3);
    let byte_slice = unsafe { core::slice::from_raw_parts(start as *const u8, CHUNK_SIZE * 7) };
    let num_spaces = hex_num_len(start.saturating_add(CHUNK_SIZE * 6)) + 1;
    (0..num_spaces).for_each(|_| print!(" "));
    println!("{}{}{}", NUMBERING_HEX, NUMBERING_SEP, NUMBERING_ASCII);
    (0..num_spaces).for_each(|_| print!(" "));
    (0..NUMBERING_HEX.len()).for_each(|_| print!("─"));
    print!("┼");
    (0..NUMBERING_ASCII.len()).for_each(|_| print!("─"));
    println!();
    byte_slice
        .chunks(CHUNK_SIZE)
        .zip((0..).map(|x| (x * CHUNK_SIZE) + start))
        .for_each(dump_hex_line)
}

fn main() {
    let x = b"AAA TEST \0\x01\x02\x03\x04";
    let x = x.as_ptr();
    
    println!("{:?}", x);
    hex_dump(x);
}

Try it: https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=b45bdbd28721e16a562f9eb976f17f0c