serve_rs/
lib.rs

1use std::{
2    sync::{
3        mpsc::{self, Receiver, Sender},
4        Arc, Mutex,
5    },
6    thread,
7};
8
9pub struct ThreadPool {
10    workers: Vec<Worker>,
11    sender: Sender<Message>,
12}
13
14type Job = Box<dyn FnOnce() + Send + 'static>;
15enum Message {
16    NewJob(Job),
17    Terminate,
18}
19
20impl ThreadPool {
21    pub fn new(size: usize) -> ThreadPool {
22        assert!(size > 0);
23        let mut workers = Vec::with_capacity(size);
24        let (sender, receiver) = mpsc::channel();
25        let receiver = Arc::new(Mutex::new(receiver));
26        for id in 0..size {
27            workers.push(Worker::new(id, Arc::clone(&receiver)))
28        }
29        ThreadPool { workers, sender }
30    }
31    pub fn execute<F>(&self, f: F)
32    where
33        F: FnOnce() + Send + 'static,
34    {
35        let job = Box::new(f);
36        self.sender.send(Message::NewJob(job)).unwrap();
37    }
38}
39
40impl Drop for ThreadPool {
41    fn drop(&mut self) {
42        println!("Sending terminate message to all workers.");
43
44        for _ in &mut self.workers {
45            self.sender.send(Message::Terminate).unwrap();
46        }
47        for worker in &mut self.workers {
48            println!("Shutting down worker {}", worker.id);
49            if let Some(thread) = worker.thread.take() {
50                thread.join().unwrap();
51            }
52        }
53    }
54}
55
56type WorkerReceiver = Arc<Mutex<Receiver<Message>>>;
57
58struct Worker {
59    id: usize,
60    thread: Option<thread::JoinHandle<()>>,
61}
62
63impl Worker {
64    fn new(id: usize, receiver: WorkerReceiver) -> Worker {
65        let thread = thread::spawn(move || loop {
66            let message = receiver.lock().unwrap().recv().unwrap();
67            match message {
68                Message::NewJob(job) => {
69                    println!("thread {} consume a job", id);
70                    job()
71                }
72                Message::Terminate => {
73                    println!("Worker {} was told to terminate.", id);
74                    break;
75                }
76            }
77        });
78        Worker {
79            id,
80            thread: Some(thread),
81        }
82    }
83}
serve_rs/lib.rs

serve_rs/
lib.rs
