server fix

server/src/main.rs

@@ -2,7 +2,7 @@
 // sever/src/main.rs
 #![forbid(unsafe_code)]
 
-use std::{pin::Pin, sync::Arc, panic::AssertUnwindSafe};
+use std::{io::ErrorKind, pin::Pin, sync::Arc, panic::AssertUnwindSafe};
 use tokio::{fs::{File, OpenOptions}, io::AsyncWriteExt, sync::Mutex};
 use tokio_stream::{wrappers::ReceiverStream, Stream, StreamExt};
 use tonic::{transport::Server, Request, Response, Status};
@@ -54,8 +54,18 @@ impl Relay for Handler {
         tokio::spawn(async move {
             let mut s = req.into_inner();
             while let Some(pkt) = s.next().await.transpose()? {
-                ms.lock().await.write_all(&pkt.data).await?;
+                loop {
-                tx.send(Ok(pkt)).await;//.ok();
+                    match ms.lock().await.write_all(&pkt.data).await {
+                        Ok(()) => break,
+                        Err(e) if e.kind() == ErrorKind::WouldBlock => {
+                            // gadget FIFO full – give it a breath
+                            tokio::time::sleep(std::time::Duration::from_micros(500)).await;
+                            continue;
+                        }
+                        Err(e) => return Err(Status::internal(format!("hidg1: {e}"))),
+                    }
+                }
+                let _ = tx.send(Ok(pkt)).await;
             }
             Ok::<(), Status>(())
         });
@@ -88,14 +98,14 @@ async fn main() -> anyhow::Result<()> {
     let kb = OpenOptions::new()
         .write(true)
         // .read(true)
-        .custom_flags(libc::O_NONBLOCK)
+        // .custom_flags(libc::O_NONBLOCK)
         .open("/dev/hidg0")
         .await?;
 
     let ms = OpenOptions::new()
         .write(true)
         // .read(true)
-        .custom_flags(libc::O_NONBLOCK)
+        // .custom_flags(libc::O_NONBLOCK)
         .open("/dev/hidg1")
         .await?;