web: Use single-threaded shared ownership for body stream

web/src/navigator.rs

@@ -13,8 +13,10 @@ use ruffle_core::indexmap::IndexMap;
 use ruffle_core::loader::Error;
 use ruffle_core::socket::{ConnectionState, SocketAction, SocketHandle};
 use std::borrow::Cow;
+use std::cell::RefCell;
+use std::rc::Rc;
 use std::sync::mpsc::Sender;
-use std::sync::{Arc, Mutex};
+use std::sync::Arc;
 use std::time::Duration;
 use tracing_subscriber::layer::Layered;
 use tracing_subscriber::Registry;
@@ -447,7 +449,7 @@ impl NavigatorBackend for WebNavigatorBackend {
 
 struct WebResponseWrapper {
     response: WebResponse,
-    body_stream: Option<Arc<Mutex<ReadableStream>>>,
+    body_stream: Option<Rc<RefCell<ReadableStream>>>,
 }
 
 impl SuccessResponse for WebResponseWrapper {
@@ -484,7 +486,7 @@ impl SuccessResponse for WebResponseWrapper {
         self.response.redirected()
     }
 
-    #[allow(clippy::await_holding_lock)]
+    #[allow(clippy::await_holding_refcell_ref)]
     fn next_chunk(&mut self) -> OwnedFuture<Option<Vec<u8>>, Error> {
         if self.body_stream.is_none() {
             let body = self.response.body();
@@ -492,15 +494,15 @@ impl SuccessResponse for WebResponseWrapper {
                 return Box::pin(async move { Ok(None) });
             }
 
-            self.body_stream = Some(Arc::new(Mutex::new(ReadableStream::from_raw(
+            self.body_stream = Some(Rc::new(RefCell::new(ReadableStream::from_raw(
                 body.expect("body").unchecked_into(),
             ))));
         }
 
         let body_stream = self.body_stream.clone().expect("web body stream");
         Box::pin(async move {
-            let read_lock = body_stream.try_lock();
-            if matches!(read_lock, Err(std::sync::TryLockError::WouldBlock)) {
+            let read_lock = body_stream.try_borrow_mut();
+            if read_lock.is_err() {
                 return Err(Error::FetchError(
                     "Concurrent read operations on the same stream are not supported.".to_string(),
                 ));