1 files changed, 86 insertions, 0 deletions
diff --git a/src/codec/bytes_codec.rs b/src/codec/bytes_codec.rs
new file mode 100644
index 0000000..ceab228
--- /dev/null
+++ b/src/codec/bytes_codec.rs
@@ -0,0 +1,86 @@
+use crate::codec::decoder::Decoder;
+use crate::codec::encoder::Encoder;
+
+use bytes::{BufMut, Bytes, BytesMut};
+use std::io;
+
+/// A simple [`Decoder`] and [`Encoder`] implementation that just ships bytes around.
+///
+/// [`Decoder`]: crate::codec::Decoder
+/// [`Encoder`]: crate::codec::Encoder
+///
+/// # Example
+///
+/// Turn an [`AsyncRead`] into a stream of `Result<`[`BytesMut`]`, `[`Error`]`>`.
+///
+/// [`AsyncRead`]: tokio::io::AsyncRead
+/// [`BytesMut`]: bytes::BytesMut
+/// [`Error`]: std::io::Error
+///
+/// ```
+/// # mod hidden {
+/// # #[allow(unused_imports)]
+/// use tokio::fs::File;
+/// # }
+/// use tokio::io::AsyncRead;
+/// use tokio_util::codec::{FramedRead, BytesCodec};
+///
+/// # enum File {}
+/// # impl File {
+/// #     async fn open(_name: &str) -> Result<impl AsyncRead, std::io::Error> {
+/// #         use std::io::Cursor;
+/// #         Ok(Cursor::new(vec![0, 1, 2, 3, 4, 5]))
+/// #     }
+/// # }
+/// #
+/// # #[tokio::main(flavor = "current_thread")]
+/// # async fn main() -> Result<(), std::io::Error> {
+/// let my_async_read = File::open("filename.txt").await?;
+/// let my_stream_of_bytes = FramedRead::new(my_async_read, BytesCodec::new());
+/// # Ok(())
+/// # }
+/// ```
+///
+#[derive(Copy, Clone, Debug, Eq, PartialEq, Ord, PartialOrd, Hash, Default)]
+pub struct BytesCodec(());
+
+impl BytesCodec {
+    /// Creates a new `BytesCodec` for shipping around raw bytes.
+    pub fn new() -> BytesCodec {
+        BytesCodec(())
+    }
+}
+
+impl Decoder for BytesCodec {
+    type Item = BytesMut;
+    type Error = io::Error;
+
+    fn decode(&mut self, buf: &mut BytesMut) -> Result<Option<BytesMut>, io::Error> {
+        if !buf.is_empty() {
+            let len = buf.len();
+            Ok(Some(buf.split_to(len)))
+        } else {
+            Ok(None)
+        }
+    }
+}
+
+impl Encoder<Bytes> for BytesCodec {
+    type Error = io::Error;
+
+    fn encode(&mut self, data: Bytes, buf: &mut BytesMut) -> Result<(), io::Error> {
+        buf.reserve(data.len());
+        buf.put(data);
+        Ok(())
+    }
+}
+
+impl Encoder<BytesMut> for BytesCodec {
+    type Error = io::Error;
+
+    fn encode(&mut self, data: BytesMut, buf: &mut BytesMut) -> Result<(), io::Error> {
+        buf.reserve(data.len());
+        buf.put(data);
+        Ok(())
+    }
+}