3 files changed, 150 insertions, 0 deletions
diff --git a/third_party/rust/tokio-threadpool/src/park/boxed.rs b/third_party/rust/tokio-threadpool/src/park/boxed.rs
new file mode 100644
index 0000000000..030866450d
--- /dev/null
+++ b/third_party/rust/tokio-threadpool/src/park/boxed.rs
@@ -0,0 +1,45 @@
+use tokio_executor::park::{Park, Unpark};
+
+use std::error::Error;
+use std::time::Duration;
+
+pub(crate) type BoxPark = Box<dyn Park<Unpark = BoxUnpark, Error = ()> + Send>;
+pub(crate) type BoxUnpark = Box<dyn Unpark>;
+
+pub(crate) struct BoxedPark<T>(T);
+
+impl<T> BoxedPark<T> {
+    pub fn new(inner: T) -> Self {
+        BoxedPark(inner)
+    }
+}
+
+impl<T: Park + Send> Park for BoxedPark<T>
+where
+    T::Error: Error,
+{
+    type Unpark = BoxUnpark;
+    type Error = ();
+
+    fn unpark(&self) -> Self::Unpark {
+        Box::new(self.0.unpark())
+    }
+
+    fn park(&mut self) -> Result<(), Self::Error> {
+        self.0.park().map_err(|e| {
+            warn!(
+                "calling `park` on worker thread errored -- shutting down thread: {}",
+                e
+            );
+        })
+    }
+
+    fn park_timeout(&mut self, duration: Duration) -> Result<(), Self::Error> {
+        self.0.park_timeout(duration).map_err(|e| {
+            warn!(
+                "calling `park` on worker thread errored -- shutting down thread: {}",
+                e
+            );
+        })
+    }
+}
diff --git a/third_party/rust/tokio-threadpool/src/park/default_park.rs b/third_party/rust/tokio-threadpool/src/park/default_park.rs
new file mode 100644
index 0000000000..ecc22350f0
--- /dev/null
+++ b/third_party/rust/tokio-threadpool/src/park/default_park.rs
@@ -0,0 +1,97 @@
+use tokio_executor::park::{Park, Unpark};
+
+use std::error::Error;
+use std::fmt;
+use std::time::Duration;
+
+use crossbeam_utils::sync::{Parker, Unparker};
+
+/// Parks the thread.
+#[derive(Debug)]
+pub struct DefaultPark {
+    inner: Parker,
+}
+
+/// Unparks threads that were parked by `DefaultPark`.
+#[derive(Debug)]
+pub struct DefaultUnpark {
+    inner: Unparker,
+}
+
+/// Error returned by [`ParkThread`]
+///
+/// This currently is never returned, but might at some point in the future.
+///
+/// [`ParkThread`]: struct.ParkThread.html
+#[derive(Debug)]
+pub struct ParkError {
+    _p: (),
+}
+
+// ===== impl DefaultPark =====
+
+impl DefaultPark {
+    /// Creates a new `DefaultPark` instance.
+    pub fn new() -> DefaultPark {
+        DefaultPark {
+            inner: Parker::new(),
+        }
+    }
+
+    /// Unpark the thread without having to clone the unpark handle.
+    ///
+    /// Named `notify` to avoid conflicting with the `unpark` fn.
+    pub(crate) fn notify(&self) {
+        self.inner.unparker().unpark();
+    }
+
+    pub(crate) fn park_sync(&self, duration: Option<Duration>) {
+        match duration {
+            None => self.inner.park(),
+            Some(duration) => self.inner.park_timeout(duration),
+        }
+    }
+}
+
+impl Park for DefaultPark {
+    type Unpark = DefaultUnpark;
+    type Error = ParkError;
+
+    fn unpark(&self) -> Self::Unpark {
+        DefaultUnpark {
+            inner: self.inner.unparker().clone(),
+        }
+    }
+
+    fn park(&mut self) -> Result<(), Self::Error> {
+        self.inner.park();
+        Ok(())
+    }
+
+    fn park_timeout(&mut self, duration: Duration) -> Result<(), Self::Error> {
+        self.inner.park_timeout(duration);
+        Ok(())
+    }
+}
+
+// ===== impl DefaultUnpark =====
+
+impl Unpark for DefaultUnpark {
+    fn unpark(&self) {
+        self.inner.unpark();
+    }
+}
+
+// ===== impl ParkError =====
+
+impl fmt::Display for ParkError {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        self.description().fmt(fmt)
+    }
+}
+
+impl Error for ParkError {
+    fn description(&self) -> &str {
+        "unknown park error"
+    }
+}
diff --git a/third_party/rust/tokio-threadpool/src/park/mod.rs b/third_party/rust/tokio-threadpool/src/park/mod.rs
new file mode 100644
index 0000000000..e7c5f40d36
--- /dev/null
+++ b/third_party/rust/tokio-threadpool/src/park/mod.rs
@@ -0,0 +1,8 @@
+//! Thread parking utilities.
+
+mod boxed;
+mod default_park;
+
+pub use self::default_park::{DefaultPark, DefaultUnpark, ParkError};
+
+pub(crate) use self::boxed::{BoxPark, BoxUnpark, BoxedPark};