signal: Refactor Signal tests

* Added timeouts to all tests that were missing them
 - any issue we have will likely result in deadlocks/starvation so its
   best if all tests quickly timeout rather than require getting killed
   or have the CI timeout itself
* Added a `support` module and put a bunch of helpers there to DRY the
tests

tests/simple.rs

@@ -1,20 +1,20 @@
 #![cfg(unix)]
 
-extern crate futures;
 extern crate libc;
-extern crate tokio_core;
-extern crate tokio_signal;
 
-use futures::stream::Stream;
-use tokio_core::reactor::Core;
-use tokio_signal::unix::Signal;
+pub mod support;
+use support::*;
 
 #[test]
 fn simple() {
     let mut lp = Core::new().unwrap();
-    let signal = lp.run(Signal::new(libc::SIGUSR1)).unwrap();
-    unsafe {
-        assert_eq!(libc::kill(libc::getpid(), libc::SIGUSR1), 0);
-    }
-    lp.run(signal.into_future()).ok().unwrap();
+
+    let signal = run_core_with_timeout(&mut lp, Signal::new(libc::SIGUSR1))
+        .expect("failed to create signal");
+
+    send_signal(libc::SIGUSR1);
+
+    run_core_with_timeout(&mut lp, signal.into_future())
+        .ok()
+        .expect("failed to get signal");
 }