Решение на упр.13 задача 1 от Георги Стоянов
Код
use std::sync::{mpsc, Arc, Mutex};
use std::thread;
pub trait Job: Send + 'static {
type Output: Send + 'static;
type Error: Send + 'static;
fn run(self) -> Result<Self::Output, Self::Error>;
}
enum Message {
Run(Box<dyn FnOnce() + Send>),
Shutdown,
}
pub struct ThreadPool {
workers: Vec<thread::JoinHandle<()>>,
sender: mpsc::Sender<Message>,
}
impl ThreadPool {
pub fn new(worker_count: usize) -> Self {
let (sender, receiver) = mpsc::channel::<Message>();
let receiver = Arc::new(Mutex::new(receiver));
let mut workers = Vec::with_capacity(worker_count);
for _ in 0..worker_count {
let thread_receiver = Arc::clone(&receiver);
let handle = thread::spawn(move || {
loop {
let msg = thread_receiver
.lock()
.expect("receiver mutex poisoned")
.recv();
match msg {
Ok(Message::Run(f)) => {
f();
}
Ok(Message::Shutdown) => break,
Err(_) => break,
}
}
});
workers.push(handle);
}
Self { workers, sender }
}
pub fn submit<J>(&self, job: J) -> mpsc::Receiver<Result<J::Output, J::Error>>
where
J: Job,
{
let (result_sender, result_receiver) = mpsc::channel();
let task = Message::Run(Box::new(move || {
let res = job.run();
let _ = result_sender.send(res);
}));
let _ = self.sender.send(task);
result_receiver
}
}
impl Drop for ThreadPool {
fn drop(&mut self) {
for _ in 0..self.workers.len() {
let _ = self.sender.send(Message::Shutdown);
}
for handle in self.workers.drain(..) {
let _ = handle.join();
}
}
}