rust-based-os-comp2022/guide-code/ch1-3mini-rt-usrland/src/console.rs

use core::fmt::{Write, Arguments, Result};
use crate::sys_write;

struct Stdout;

impl Write for Stdout {
    fn write_str(&mut self, s: &str) -> Result {
        sys_write(1, s.as_bytes());
        Ok(())
    }
}

pub fn print(args: Arguments) {
    Stdout.write_fmt(args).unwrap();
}

macro_rules! print {
    ($fmt: literal $(, $($arg: tt)+)?) => {
        $crate::console::print(format_args!($fmt $(, $($arg)+)?));
    }
}

macro_rules! println {
    ($fmt: literal $(, $($arg: tt)+)?) => {
        $crate::console::print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?));
    }
}