1 // The Computer Language Benchmarks Game
2 // http://benchmarksgame.alioth.debian.org/
4 // contributed by the Rust Project Developers
6 // Copyright (c) 2012-2014 The Rust Project Developers
8 // All rights reserved.
10 // Redistribution and use in source and binary forms, with or without
11 // modification, are permitted provided that the following conditions
14 // - Redistributions of source code must retain the above copyright
15 // notice, this list of conditions and the following disclaimer.
17 // - Redistributions in binary form must reproduce the above copyright
18 // notice, this list of conditions and the following disclaimer in
19 // the documentation and/or other materials provided with the
22 // - Neither the name of "The Computer Language Benchmarks Game" nor
23 // the name of "The Computer Language Shootout Benchmarks" nor the
24 // names of its contributors may be used to endorse or promote
25 // products derived from this software without specific prior
26 // written permission.
28 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
31 // FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
32 // COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
33 // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
34 // (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
35 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 // HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
37 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
38 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
39 // OF THE POSSIBILITY OF SUCH DAMAGE.
41 use std::sync::mpsc::{channel, Sender, Receiver};
44 fn start(n_tasks: i32, token: i32) {
45 let (tx, mut rx) = channel();
46 tx.send(token).unwrap();
47 let mut guards = Vec::with_capacity(n_tasks as usize);
48 for i in 2 .. n_tasks + 1 {
49 let (tx, next_rx) = channel();
50 let cur_rx = std::mem::replace(&mut rx, next_rx);
51 guards.push(thread::spawn(move|| roundtrip(i, tx, cur_rx)));
53 let guard = thread::spawn(move|| roundtrip(1, tx, rx));
56 fn roundtrip(id: i32, tx: Sender<i32>, rx: Receiver<i32>) {
57 for token in rx.iter() {
62 tx.send(token - 1).unwrap();
67 let mut args = std::env::args();
68 let token = if std::env::var_os("RUST_BENCH").is_some() {
71 args.nth(1).and_then(|arg| arg.parse().ok()).unwrap_or(1000)
73 let n_tasks = args.next()
74 .and_then(|arg| arg.parse().ok())
77 start(n_tasks, token);