Impl BufRead for ReadableRx

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

src/helpers/readable_rx.rs

@@ -1,5 +1,5 @@
 use std::cmp::min;
-use std::io::{self, Read};
+use std::io::{self, BufRead, Read};
 
 use bytes::{Buf, Bytes};
 use tokio::sync::mpsc::Receiver;
@@ -27,17 +27,12 @@ impl Read for ReadableRx<'_> {
             return Ok(0);
         }
 
-        let bytes = &mut self.bytes;
-        if !bytes.has_remaining() {
-            match self.rx.blocking_recv() {
-                Some(Content::Data(new_bytes)) => *bytes = new_bytes,
-                Some(Content::Abort) => {
-                    return Err(io::Error::new(io::ErrorKind::Other, "Aborted"))
-                }
-                None => return Ok(0),
-            }
+        if self.fill_buf()?.is_empty() {
+            return Ok(0);
         }
 
+        let bytes = &mut self.bytes;
+
         // copy_to_slice requires the bytes to have enough remaining bytes
         // to fill buf.
         let n = min(buf.len(), bytes.remaining());
@@ -47,3 +42,23 @@ impl Read for ReadableRx<'_> {
         Ok(n)
     }
 }
+
+impl BufRead for ReadableRx<'_> {
+    fn fill_buf(&mut self) -> io::Result<&[u8]> {
+        let bytes = &mut self.bytes;
+        if !bytes.has_remaining() {
+            match self.rx.blocking_recv() {
+                Some(Content::Data(new_bytes)) => *bytes = new_bytes,
+                Some(Content::Abort) => {
+                    return Err(io::Error::new(io::ErrorKind::Other, "Aborted"))
+                }
+                None => (),
+            }
+        }
+        Ok(&*bytes)
+    }
+
+    fn consume(&mut self, amt: usize) {
+        self.bytes.advance(amt);
+    }
+}