rustlings/exercises/threads/threads1.rs

// threads1.rs
//
// This program spawns multiple threads that each run for at least 250ms, and
// each thread returns how much time they took to complete. The program should
// wait until all the spawned threads have finished and should collect their
// return values into a vector.
//
// Execute `rustlings hint threads1` or use the `hint` watch subcommand for a
// hint.

use std::sync::{Arc, Mutex};
use std::thread;
use std::time::{Duration, Instant};

fn main() {
    // Introduce Mutex
    let status = Arc::new(Mutex::new(JobStatus { jobs_completed: 0 }));
    let status_shared = status.clone();
    thread::spawn(move || {
        for _ in 0..10 {
            thread::sleep(Duration::from_millis(250));
            // Lock mutex and make mutable
            let mut jobStatus = status_shared.lock().unwrap();
            jobStatus.jobs_completed += 1;
        }
    });
    // Not assigning should release lock before sleep
    while status.lock().unwrap().jobs_completed < 10 {
        println!("waiting... ");
        thread::sleep(Duration::from_millis(500));
    }
}