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#[macro_use]
extern crate futures;
#[macro_use]
extern crate loom;
#[path = "../src/semaphore.rs"]
#[allow(warnings)]
mod semaphore;
use semaphore::*;
use futures::{future, Async, Future, Poll};
use loom::futures::block_on;
use loom::thread;
use std::sync::atomic::AtomicUsize;
use std::sync::atomic::Ordering::SeqCst;
use std::sync::Arc;
#[test]
fn basic_usage() {
const NUM: usize = 2;
struct Actor {
waiter: Permit,
shared: Arc<Shared>,
}
struct Shared {
semaphore: Semaphore,
active: AtomicUsize,
}
impl Future for Actor {
type Item = ();
type Error = ();
fn poll(&mut self) -> Poll<(), ()> {
try_ready!(self
.waiter
.poll_acquire(&self.shared.semaphore)
.map_err(|_| ()));
let actual = self.shared.active.fetch_add(1, SeqCst);
assert!(actual <= NUM - 1);
let actual = self.shared.active.fetch_sub(1, SeqCst);
assert!(actual <= NUM);
self.waiter.release(&self.shared.semaphore);
Ok(Async::Ready(()))
}
}
loom::fuzz(|| {
let shared = Arc::new(Shared {
semaphore: Semaphore::new(NUM),
active: AtomicUsize::new(0),
});
for _ in 0..NUM {
let shared = shared.clone();
thread::spawn(move || {
block_on(Actor {
waiter: Permit::new(),
shared,
})
.unwrap();
});
}
block_on(Actor {
waiter: Permit::new(),
shared,
})
.unwrap();
});
}
#[test]
fn release() {
loom::fuzz(|| {
let semaphore = Arc::new(Semaphore::new(1));
{
let semaphore = semaphore.clone();
thread::spawn(move || {
let mut permit = Permit::new();
block_on(future::lazy(|| {
permit.poll_acquire(&semaphore).unwrap();
Ok::<_, ()>(())
}))
.unwrap();
permit.release(&semaphore);
});
}
let mut permit = Permit::new();
block_on(future::poll_fn(|| permit.poll_acquire(&semaphore))).unwrap();
permit.release(&semaphore);
});
}
#[test]
fn basic_closing() {
const NUM: usize = 2;
loom::fuzz(|| {
let semaphore = Arc::new(Semaphore::new(1));
for _ in 0..NUM {
let semaphore = semaphore.clone();
thread::spawn(move || {
let mut permit = Permit::new();
for _ in 0..2 {
block_on(future::poll_fn(|| {
permit.poll_acquire(&semaphore).map_err(|_| ())
}))?;
permit.release(&semaphore);
}
Ok::<(), ()>(())
});
}
semaphore.close();
});
}
#[test]
fn concurrent_close() {
const NUM: usize = 3;
loom::fuzz(|| {
let semaphore = Arc::new(Semaphore::new(1));
for _ in 0..NUM {
let semaphore = semaphore.clone();
thread::spawn(move || {
let mut permit = Permit::new();
block_on(future::poll_fn(|| {
permit.poll_acquire(&semaphore).map_err(|_| ())
}))?;
permit.release(&semaphore);
semaphore.close();
Ok::<(), ()>(())
});
}
});
}
|
