task -> thread

components/util/threadpool.rs

@@ -0,0 +1,55 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+//! A load-balancing thread pool.
+//!
+//! This differs in implementation from std::sync::ThreadPool in that each job is
+//! up for grabs by any of the child threads in the pool.
+//!
+
+//
+// This is based on the cargo thread pool.
+// https://github.com/rust-lang/cargo/blob/master/src/cargo/util/pool.rs
+//
+// The only difference is that a normal channel is used instead of a sync_channel.
+//
+
+use std::boxed::FnBox;
+use std::sync::mpsc::{Receiver, Sender, channel};
+use std::sync::{Arc, Mutex};
+use thread::spawn_named;
+
+pub struct ThreadPool {
+    tx: Sender<Box<FnBox() + Send + 'static>>,
+}
+
+impl ThreadPool {
+    pub fn new(threads: u32) -> ThreadPool {
+        assert!(threads > 0);
+        let (tx, rx) = channel();
+
+        let state = Arc::new(Mutex::new(rx));
+
+        for i in 0..threads {
+            let state = state.clone();
+            spawn_named(
+                format!("ThreadPoolWorker {}/{}", i + 1, threads),
+                move || worker(&*state));
+        }
+
+        return ThreadPool { tx: tx };
+
+        fn worker(rx: &Mutex<Receiver<Box<FnBox() + Send + 'static>>>) {
+            while let Ok(job) = rx.lock().unwrap().recv() {
+                job.call_box(());
+            }
+        }
+    }
+
+    pub fn execute<F>(&self, job: F)
+        where F: FnOnce() + Send + 'static
+    {
+        self.tx.send(Box::new(job)).unwrap();
+    }
+}