A script that restart failed ssh connection automatically.

rautossh.rs

use std::os::windows::process::CommandExt;
use std::process::{self, Command, Stdio};
use std::time::{Duration, Instant};
use std::{env, thread};

fn main() {
    let mut args: Vec<_> = env::args().collect();
    if let Some(idx) = args.iter().position(|x| x == "--detach") {
        args.remove(idx);
        if let Err(e) = Command::new(&args[0])
            .args(&args[1..])
            .creation_flags(0x0000_0200 | 0x0000_0008 | 0x0400_0000)
            .spawn()
        {
            eprintln!("Failed to run in detach mode: {:?}", e);
        }
        return;
    }
    let mut timer = Instant::now();
    loop {
        let cmd = match Command::new("ssh")
            .arg("-NT")
            .args(&args[1..])
            .stderr(Stdio::piped())
            .creation_flags(0x0800_0000)
            .spawn()
        {
            Ok(c) => c,
            Err(e) => {
                eprintln!("Failed to spawn ssh {:?}: {}", args, e);
                process::exit(1);
            }
        };
        let output = match cmd.wait_with_output() {
            Ok(output) => output,
            Err(e) => {
                eprintln!("Failed to wait on ssh: {}", e);
                process::exit(1);
            }
        };
        if output.status.code() != Some(255) {
            return;
        }
        let elapsed = timer.elapsed();
        if elapsed < Duration::from_secs(5) {
            thread::sleep(Duration::from_secs(5) - elapsed);
        }
        timer = Instant::now();
    }
}