1 files changed, 33 insertions, 0 deletions

diff --git a/crates/server/src/thread_watcher.rs b/crates/server/src/thread_watcher.rs
new file mode 100644
index 000000000..98bcdfd6c
--- /dev/null
+++ b/crates/server/src/thread_watcher.rs
@@ -0,0 +1,33 @@
+use std::thread;
+use drop_bomb::DropBomb;
+use Result;
+
+pub struct ThreadWatcher {
+    name: &'static str,
+    thread: thread::JoinHandle<()>,
+    bomb: DropBomb,
+}
+
+impl ThreadWatcher {
+    pub fn spawn(name: &'static str, f: impl FnOnce() + Send + 'static) -> ThreadWatcher {
+        let thread = thread::spawn(f);
+        ThreadWatcher {
+            name,
+            thread,
+            bomb: DropBomb::new(format!("ThreadWatcher {} was not stopped", name)),
+        }
+    }
+
+    pub fn stop(mut self) -> Result<()> {
+        info!("waiting for {} to finish ...", self.name);
+        let name = self.name;
+        self.bomb.defuse();
+        let res = self.thread.join()
+            .map_err(|_| format_err!("ThreadWatcher {} died", name));
+        match &res {
+            Ok(()) => info!("... {} terminated with ok", name),
+            Err(_) => error!("... {} terminated with err", name)
+        }
+        res
+    }
+}