Fix panic when flush_interval is set to 0 (#136)

* Fix panic when flush_interval is set to 0

Fixed #135

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

* Fix checking duration is zero

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

* Fix integration tests

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

* Revert previous commit

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

* Update src/tasks.rs

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>

* Test `flush_interval` set to 0

Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

---------

Signed-off-by: Jiahao XU <30436523+NobodyXu@users.noreply.github.com>
Signed-off-by: Jiahao XU <Jiahao_XU@outlook.com>

src/tasks.rs

@@ -65,8 +65,13 @@ pub(super) fn create_flush_task<W: AsyncWrite + Send + 'static>(
         write_end_buffer_size: NonZeroUsize,
         flush_interval: Duration,
     ) -> Result<(), Error> {
-        let mut interval = time::interval(flush_interval);
-        interval.set_missed_tick_behavior(time::MissedTickBehavior::Delay);
+        let mut interval = if !flush_interval.is_zero() {
+            let mut interval = time::interval(flush_interval);
+            interval.set_missed_tick_behavior(time::MissedTickBehavior::Delay);
+            Some(interval)
+        } else {
+            None
+        };
 
         let auxiliary = shared_data.get_auxiliary();
         let flush_end_notify = &auxiliary.flush_end_notify;
@@ -133,18 +138,20 @@ pub(super) fn create_flush_task<W: AsyncWrite + Send + 'static>(
 
             flush_end_notify.notified().await;
 
-            tokio::select! {
-                biased;
-
-                _ = interval.tick() => (),
-                // tokio::sync::Notify is cancel safe, however
-                // cancelling it would lose the place in the queue.
-                //
-                // However, since flush_task is the only one who
-                // calls `flush_immediately.notified()`, it
-                // is totally fine to cancel here.
-                _ = auxiliary.flush_immediately.notified() => (),
-            };
+            if let Some(interval) = interval.as_mut() {
+                tokio::select! {
+                    biased;
+
+                    _ = interval.tick() => (),
+                    // tokio::sync::Notify is cancel safe, however
+                    // cancelling it would lose the place in the queue.
+                    //
+                    // However, since flush_task is the only one who
+                    // calls `flush_immediately.notified()`, it
+                    // is totally fine to cancel here.
+                    _ = auxiliary.flush_immediately.notified() => (),
+                };
+            }
         }
     }
 

tests/highlevel.rs

@@ -58,7 +58,8 @@ async fn sftp_file_basics() {
 
     let content = b"HELLO, WORLD!\n".repeat(200);
 
-    let (mut child, sftp) = connect(Default::default()).await;
+    let (mut child, sftp) =
+        connect(SftpOptions::new().flush_interval(Duration::from_secs(0))).await;
 
     let content = &content[..min(sftp.max_write_len() as usize, content.len())];