core: introduce `resource.read_return` (#14331)

4 files changed, 25 insertions, 16 deletions

diff --git a/ext/fetch/lib.rs b/ext/fetch/lib.rs
index c216d53fa..def823d8f 100644
--- a/ext/fetch/lib.rs
+++ b/ext/fetch/lib.rs
@@ -485,12 +485,15 @@ impl Resource for FetchResponseBodyResource {
     "fetchResponseBody".into()
   }
 
-  fn read(self: Rc<Self>, mut buf: ZeroCopyBuf) -> AsyncResult<usize> {
+  fn read_return(
+    self: Rc<Self>,
+    mut buf: ZeroCopyBuf,
+  ) -> AsyncResult<(usize, ZeroCopyBuf)> {
     Box::pin(async move {
       let mut reader = RcRef::map(&self, |r| &r.reader).borrow_mut().await;
       let cancel = RcRef::map(self, |r| &r.cancel);
       let read = reader.read(&mut buf).try_or_cancel(cancel).await?;
-      Ok(read)
+      Ok((read, buf))
     })
   }
 
diff --git a/ext/http/lib.rs b/ext/http/lib.rs
index dff5c14cb..b85dcc473 100644
--- a/ext/http/lib.rs
+++ b/ext/http/lib.rs
@@ -688,16 +688,13 @@ async fn op_http_write_resource(
       }
     };
 
-    let mut vec = vec![0u8; 64 * 1024];
-    let vec_ptr = vec.as_mut_ptr();
+    let vec = vec![0u8; 64 * 1024]; // 64KB
     let buf = ZeroCopyBuf::new_temp(vec);
-    let nread = resource.clone().read(buf).await?;
+    let (nread, buf) = resource.clone().read_return(buf).await?;
     if nread == 0 {
       break;
     }
-    // SAFETY: ZeroCopyBuf keeps the Vec<u8> alive.
-    let bytes =
-      Bytes::from_static(unsafe { std::slice::from_raw_parts(vec_ptr, nread) });
+    let bytes = Bytes::from(buf.to_temp());
     match body_tx.send_data(bytes).await {
       Ok(_) => {}
       Err(err) => {
diff --git a/ext/net/io.rs b/ext/net/io.rs
index 17b86af17..02caf7473 100644
--- a/ext/net/io.rs
+++ b/ext/net/io.rs
@@ -70,13 +70,13 @@ where
   pub async fn read(
     self: Rc<Self>,
     mut buf: ZeroCopyBuf,
-  ) -> Result<usize, AnyError> {
+  ) -> Result<(usize, ZeroCopyBuf), AnyError> {
     let mut rd = self.rd_borrow_mut().await;
     let nread = rd
       .read(&mut buf)
       .try_or_cancel(self.cancel_handle())
       .await?;
-    Ok(nread)
+    Ok((nread, buf))
   }
 
   pub async fn write(
@@ -103,7 +103,10 @@ impl Resource for TcpStreamResource {
     "tcpStream".into()
   }
 
-  fn read(self: Rc<Self>, buf: ZeroCopyBuf) -> AsyncResult<usize> {
+  fn read_return(
+    self: Rc<Self>,
+    buf: ZeroCopyBuf,
+  ) -> AsyncResult<(usize, ZeroCopyBuf)> {
     Box::pin(self.read(buf))
   }
 
@@ -160,7 +163,7 @@ impl UnixStreamResource {
   pub async fn read(
     self: Rc<Self>,
     _buf: ZeroCopyBuf,
-  ) -> Result<usize, AnyError> {
+  ) -> Result<(usize, ZeroCopyBuf), AnyError> {
     unreachable!()
   }
   pub async fn write(
@@ -182,7 +185,10 @@ impl Resource for UnixStreamResource {
     "unixStream".into()
   }
 
-  fn read(self: Rc<Self>, buf: ZeroCopyBuf) -> AsyncResult<usize> {
+  fn read_return(
+    self: Rc<Self>,
+    buf: ZeroCopyBuf,
+  ) -> AsyncResult<(usize, ZeroCopyBuf)> {
     Box::pin(self.read(buf))
   }
 
diff --git a/ext/net/ops_tls.rs b/ext/net/ops_tls.rs
index d6b83e6e8..ca922203c 100644
--- a/ext/net/ops_tls.rs
+++ b/ext/net/ops_tls.rs
@@ -674,11 +674,11 @@ impl TlsStreamResource {
   pub async fn read(
     self: Rc<Self>,
     mut buf: ZeroCopyBuf,
-  ) -> Result<usize, AnyError> {
+  ) -> Result<(usize, ZeroCopyBuf), AnyError> {
     let mut rd = RcRef::map(&self, |r| &r.rd).borrow_mut().await;
     let cancel_handle = RcRef::map(&self, |r| &r.cancel_handle);
     let nread = rd.read(&mut buf).try_or_cancel(cancel_handle).await?;
-    Ok(nread)
+    Ok((nread, buf))
   }
 
   pub async fn write(
@@ -722,7 +722,10 @@ impl Resource for TlsStreamResource {
     "tlsStream".into()
   }
 
-  fn read(self: Rc<Self>, buf: ZeroCopyBuf) -> AsyncResult<usize> {
+  fn read_return(
+    self: Rc<Self>,
+    buf: ZeroCopyBuf,
+  ) -> AsyncResult<(usize, ZeroCopyBuf)> {
     Box::pin(self.read(buf))
   }