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/notify_both.rs

@@ -1,32 +1,27 @@
 #![cfg(unix)]
 
-extern crate futures;
 extern crate libc;
-extern crate tokio;
-extern crate tokio_core;
-extern crate tokio_signal;
 
-use futures::stream::Stream;
-use futures::Future;
-use tokio_core::reactor::Core;
-use tokio_signal::unix::Signal;
+pub mod support;
+use support::*;
 
 #[test]
 fn notify_both() {
     let mut lp = Core::new().unwrap();
     let handle = lp.handle();
-    let signal1 = lp.run(Signal::with_handle(
+
+    let signal1 = run_core_with_timeout(&mut lp, Signal::with_handle(
         libc::SIGUSR2,
         &handle.new_tokio_handle(),
-    )).unwrap();
-    let signal2 = lp.run(Signal::with_handle(
+    )).expect("failed to create signal1");
+
+    let signal2 = run_core_with_timeout(&mut lp, Signal::with_handle(
         libc::SIGUSR2,
         &handle.new_tokio_handle(),
-    )).unwrap();
-    unsafe {
-        assert_eq!(libc::kill(libc::getpid(), libc::SIGUSR2), 0);
-    }
-    lp.run(signal1.into_future().join(signal2.into_future()))
+    )).expect("failed to create signal2");
+
+    send_signal(libc::SIGUSR2);
+    run_core_with_timeout(&mut lp, signal1.into_future().join(signal2.into_future()))
         .ok()
-        .unwrap();
+        .expect("failed to create signal2");
 }