finish BufRead

src/io/read/chain.rs

@@ -139,28 +139,26 @@ impl<T: Read + Unpin, U: Read + Unpin> Read for Chain<T, U> {
 }
 
 impl<T: BufRead + Unpin, U: BufRead + Unpin> BufRead for Chain<T, U> {
-    fn poll_fill_buf(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
-        // FIXME: how to make this compile?
-
-        // let Self {
-        //     first,
-        //     second,
-        //     done_first
-        // } = &mut *self;
-
-        // if !*done_first {
-        //     let rd = Pin::new(first);
-
-        //     match futures_core::ready!(rd.poll_fill_buf(cx)) {
-        //         Ok(buf) if buf.is_empty() => { *done_first = true; }
-        //         Ok(buf) => return Poll::Ready(Ok(buf)),
-        //         Err(err) => return Poll::Ready(Err(err)),
-        //     }
-        // }
-
-        // let rd = Pin::new(second);
-        // rd.poll_fill_buf(cx)
-        unimplemented!()
+    fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
+        let Self {
+            first,
+            second,
+            done_first,
+        } = unsafe { self.get_unchecked_mut() };
+
+        if !*done_first {
+            let first = unsafe { Pin::new_unchecked(first) };
+            match futures_core::ready!(first.poll_fill_buf(cx)) {
+                Ok(buf) if buf.is_empty() => {
+                    *done_first = true;
+                }
+                Ok(buf) => return Poll::Ready(Ok(buf)),
+                Err(err) => return Poll::Ready(Err(err)),
+            }
+        }
+
+        let second = unsafe { Pin::new_unchecked(second) };
+        second.poll_fill_buf(cx)
     }
 
     fn consume(mut self: Pin<&mut Self>, amt: usize) {

src/io/read/take.rs

@@ -187,28 +187,21 @@ pub fn take_read_internal<R: Read + ?Sized>(
 }
 
 impl<T: BufRead + Unpin> BufRead for Take<T> {
-    fn poll_fill_buf(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
-        // FIXME: how to get this to compile?
-        unimplemented!();
-
-        // let Self {
-        //     inner,
-        //     limit,
-        // } = &mut *self;
-
-        // if *limit == 0 {
-        //     return Poll::Ready(Ok(&[]));
-        // }
-
-        // let rd = Pin::new(inner);
-
-        // match futures_core::ready!(rd.poll_fill_buf(cx)) {
-        //     Ok(buf) => {
-        //         let cap = cmp::min(buf.len() as u64, *limit) as usize;
-        //         Poll::Ready(Ok(&buf[..cap]))
-        //     }
-        //     Err(e) => Poll::Ready(Err(e)),
-        // }
+    fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
+        let Self { inner, limit } = unsafe { self.get_unchecked_mut() };
+        let inner = unsafe { Pin::new_unchecked(inner) };
+
+        if *limit == 0 {
+            return Poll::Ready(Ok(&[]));
+        }
+
+        match futures_core::ready!(inner.poll_fill_buf(cx)) {
+            Ok(buf) => {
+                let cap = cmp::min(buf.len() as u64, *limit) as usize;
+                Poll::Ready(Ok(&buf[..cap]))
+            }
+            Err(e) => Poll::Ready(Err(e)),
+        }
     }
 
     fn consume(mut self: Pin<&mut Self>, amt: usize) {