tools: add tokio::main() replacement

to deal with block_on() not allowing blocking()

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

src/tools.rs

@@ -22,6 +22,7 @@ pub mod borrow;
 pub mod daemon;
 pub mod fs;
 pub mod futures;
+pub mod runtime;
 pub mod ticket;
 pub mod timer;
 pub mod tty;

src/tools/runtime.rs

@@ -0,0 +1,20 @@
+//! Helpers for quirks of the current tokio runtime.
+
+use std::future::Future;
+
+pub fn main<F, T>(fut: F) -> T
+where
+    F: Future<Output = T> + Send + 'static,
+    T: std::fmt::Debug + Send + 'static,
+{
+    let rt = tokio::runtime::Runtime::new().unwrap();
+    rt.block_on(async {
+        let (tx, rx) = tokio::sync::oneshot::channel();
+
+        tokio::spawn(async move {
+            tx.send(fut.await).unwrap()
+        });
+
+        rx.await.unwrap()
+    })
+}

src/tools/wrapped_reader_stream.rs

@@ -52,16 +52,10 @@ mod test {
 
     #[test]
     fn test_wrapped_stream_reader() -> Result<(), Error> {
-        let rt = tokio::runtime::Runtime::new()?;
-
         // This cannot be used currently, because it doesn't permit blocking() annotations:
-        //rt.block_on(run_wrapped_stream_reader_test());
-
-        rt.spawn(async {
-            run_wrapped_stream_reader_test().await.unwrap();
-        });
-        rt.shutdown_on_idle();
-        Ok(())
+        crate::tools::runtime::main(async {
+            run_wrapped_stream_reader_test().await
+        })
     }
 
     struct DummyReader(usize);