Create tokio-codec (#360)

Create a new tokio-codec crate with many of the contents of
`tokio_io::codec`.

tokio-codec/tests/codecs.rs

@@ -0,0 +1,76 @@
+extern crate tokio_codec;
+extern crate bytes;
+
+use bytes::{BytesMut, Bytes, BufMut};
+use tokio_codec::{BytesCodec, LinesCodec, Decoder, Encoder};
+
+#[test]
+fn bytes_decoder() {
+    let mut codec = BytesCodec::new();
+    let buf = &mut BytesMut::new();
+    buf.put_slice(b"abc");
+    assert_eq!("abc", codec.decode(buf).unwrap().unwrap());
+    assert_eq!(None, codec.decode(buf).unwrap());
+    assert_eq!(None, codec.decode(buf).unwrap());
+    buf.put_slice(b"a");
+    assert_eq!("a", codec.decode(buf).unwrap().unwrap());
+}
+
+#[test]
+fn bytes_encoder() {
+    let mut codec = BytesCodec::new();
+
+    // Default capacity of BytesMut
+    #[cfg(target_pointer_width = "64")]
+    const INLINE_CAP: usize = 4 * 8 - 1;
+    #[cfg(target_pointer_width = "32")]
+    const INLINE_CAP: usize = 4 * 4 - 1;
+
+    let mut buf = BytesMut::new();
+    codec.encode(Bytes::from_static(&[0; INLINE_CAP + 1]), &mut buf).unwrap();
+
+    // Default capacity of Framed Read
+    const INITIAL_CAPACITY: usize = 8 * 1024;
+
+    let mut buf = BytesMut::with_capacity(INITIAL_CAPACITY);
+    codec.encode(Bytes::from_static(&[0; INITIAL_CAPACITY + 1]), &mut buf).unwrap();
+}
+
+#[test]
+fn lines_decoder() {
+    let mut codec = LinesCodec::new();
+    let buf = &mut BytesMut::new();
+    buf.reserve(200);
+    buf.put("line 1\nline 2\r\nline 3\n\r\n\r");
+    assert_eq!("line 1", codec.decode(buf).unwrap().unwrap());
+    assert_eq!("line 2", codec.decode(buf).unwrap().unwrap());
+    assert_eq!("line 3", codec.decode(buf).unwrap().unwrap());
+    assert_eq!("", codec.decode(buf).unwrap().unwrap());
+    assert_eq!(None, codec.decode(buf).unwrap());
+    assert_eq!(None, codec.decode_eof(buf).unwrap());
+    buf.put("k");
+    assert_eq!(None, codec.decode(buf).unwrap());
+    assert_eq!("\rk", codec.decode_eof(buf).unwrap().unwrap());
+    assert_eq!(None, codec.decode(buf).unwrap());
+    assert_eq!(None, codec.decode_eof(buf).unwrap());
+}
+
+#[test]
+fn lines_encoder() {
+    let mut codec = BytesCodec::new();
+
+    // Default capacity of BytesMut
+    #[cfg(target_pointer_width = "64")]
+    const INLINE_CAP: usize = 4 * 8 - 1;
+    #[cfg(target_pointer_width = "32")]
+    const INLINE_CAP: usize = 4 * 4 - 1;
+
+    let mut buf = BytesMut::new();
+    codec.encode(Bytes::from_static(&[b'a'; INLINE_CAP + 1]), &mut buf).unwrap();
+
+    // Default capacity of Framed Read
+    const INITIAL_CAPACITY: usize = 8 * 1024;
+
+    let mut buf = BytesMut::with_capacity(INITIAL_CAPACITY);
+    codec.encode(Bytes::from_static(&[b'a'; INITIAL_CAPACITY + 1]), &mut buf).unwrap();
+}

tokio-codec/tests/framed.rs

@@ -0,0 +1,97 @@
+extern crate tokio_codec;
+extern crate tokio_io;
+extern crate bytes;
+extern crate futures;
+
+use futures::{Stream, Future};
+use std::io::{self, Read};
+use tokio_codec::{Framed, FramedParts, Decoder, Encoder};
+use tokio_io::AsyncRead;
+use bytes::{BytesMut, Buf, BufMut, IntoBuf, BigEndian};
+
+const INITIAL_CAPACITY: usize = 8 * 1024;
+
+struct U32Codec;
+
+impl Decoder for U32Codec {
+    type Item = u32;
+    type Error = io::Error;
+
+    fn decode(&mut self, buf: &mut BytesMut) -> io::Result<Option<u32>> {
+        if buf.len() < 4 {
+            return Ok(None);
+        }
+
+        let n = buf.split_to(4).into_buf().get_u32_be();
+        Ok(Some(n))
+    }
+}
+
+impl Encoder for U32Codec {
+    type Item = u32;
+    type Error = io::Error;
+
+    fn encode(&mut self, item: u32, dst: &mut BytesMut) -> io::Result<()> {
+        // Reserve space
+        dst.reserve(4);
+        dst.put_u32_be(item);
+        Ok(())
+    }
+}
+
+struct DontReadIntoThis;
+
+impl Read for DontReadIntoThis {
+    fn read(&mut self, _: &mut [u8]) -> io::Result<usize> {
+        Err(io::Error::new(io::ErrorKind::Other,
+                           "Read into something you weren't supposed to."))
+    }
+}
+
+impl AsyncRead for DontReadIntoThis {}
+
+#[test]
+fn can_read_from_existing_buf() {
+    let parts = FramedParts {
+        inner: DontReadIntoThis,
+        readbuf: vec![0, 0, 0, 42].into(),
+        writebuf: BytesMut::with_capacity(0),
+    };
+    let framed = Framed::from_parts(parts, U32Codec);
+
+    let num = framed
+        .into_future()
+        .map(|(first_num, _)| {
+            first_num.unwrap()
+        })
+        .wait()
+        .map_err(|e| e.0)
+        .unwrap();
+    assert_eq!(num, 42);
+}
+
+#[test]
+fn external_buf_grows_to_init() {
+    let parts = FramedParts {
+        inner: DontReadIntoThis,
+        readbuf: vec![0, 0, 0, 42].into(),
+        writebuf: BytesMut::with_capacity(0),
+    };
+    let framed = Framed::from_parts(parts, U32Codec);
+    let FramedParts { readbuf, .. } = framed.into_parts();
+
+    assert_eq!(readbuf.capacity(), INITIAL_CAPACITY);
+}
+
+#[test]
+fn external_buf_does_not_shrink() {
+    let parts = FramedParts {
+        inner: DontReadIntoThis,
+        readbuf: vec![0; INITIAL_CAPACITY * 2].into(),
+        writebuf: BytesMut::with_capacity(0),
+    };
+    let framed = Framed::from_parts(parts, U32Codec);
+    let FramedParts { readbuf, .. } = framed.into_parts();
+
+    assert_eq!(readbuf.capacity(), INITIAL_CAPACITY * 2);
+}

tokio-codec/tests/framed_read.rs

@@ -0,0 +1,216 @@
+extern crate tokio_codec;
+extern crate tokio_io;
+extern crate bytes;
+extern crate futures;
+
+use tokio_io::AsyncRead;
+use tokio_codec::{FramedRead, Decoder};
+
+use bytes::{BytesMut, Buf, IntoBuf, BigEndian};
+use futures::Stream;
+use futures::Async::{Ready, NotReady};
+
+use std::io::{self, Read};
+use std::collections::VecDeque;
+
+macro_rules! mock {
+    ($($x:expr,)*) => {{
+        let mut v = VecDeque::new();
+        v.extend(vec![$($x),*]);
+        Mock { calls: v }
+    }};
+}
+
+struct U32Decoder;
+
+impl Decoder for U32Decoder {
+    type Item = u32;
+    type Error = io::Error;
+
+    fn decode(&mut self, buf: &mut BytesMut) -> io::Result<Option<u32>> {
+        if buf.len() < 4 {
+            return Ok(None);
+        }
+
+        let n = buf.split_to(4).into_buf().get_u32::<BigEndian>();
+        Ok(Some(n))
+    }
+}
+
+#[test]
+fn read_multi_frame_in_packet() {
+    let mock = mock! {
+        Ok(b"\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02".to_vec()),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(1)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(2)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+}
+
+#[test]
+fn read_multi_frame_across_packets() {
+    let mock = mock! {
+        Ok(b"\x00\x00\x00\x00".to_vec()),
+        Ok(b"\x00\x00\x00\x01".to_vec()),
+        Ok(b"\x00\x00\x00\x02".to_vec()),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(1)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(2)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+}
+
+#[test]
+fn read_not_ready() {
+    let mock = mock! {
+        Err(io::Error::new(io::ErrorKind::WouldBlock, "")),
+        Ok(b"\x00\x00\x00\x00".to_vec()),
+        Ok(b"\x00\x00\x00\x01".to_vec()),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(NotReady, framed.poll().unwrap());
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(1)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+}
+
+#[test]
+fn read_partial_then_not_ready() {
+    let mock = mock! {
+        Ok(b"\x00\x00".to_vec()),
+        Err(io::Error::new(io::ErrorKind::WouldBlock, "")),
+        Ok(b"\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02".to_vec()),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(NotReady, framed.poll().unwrap());
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(1)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(2)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+}
+
+#[test]
+fn read_err() {
+    let mock = mock! {
+        Err(io::Error::new(io::ErrorKind::Other, "")),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(io::ErrorKind::Other, framed.poll().unwrap_err().kind());
+}
+
+#[test]
+fn read_partial_then_err() {
+    let mock = mock! {
+        Ok(b"\x00\x00".to_vec()),
+        Err(io::Error::new(io::ErrorKind::Other, "")),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(io::ErrorKind::Other, framed.poll().unwrap_err().kind());
+}
+
+#[test]
+fn read_partial_would_block_then_err() {
+    let mock = mock! {
+        Ok(b"\x00\x00".to_vec()),
+        Err(io::Error::new(io::ErrorKind::WouldBlock, "")),
+        Err(io::Error::new(io::ErrorKind::Other, "")),
+    };
+
+    let mut framed = FramedRead::new(mock, U32Decoder);
+    assert_eq!(NotReady, framed.poll().unwrap());
+    assert_eq!(io::ErrorKind::Other, framed.poll().unwrap_err().kind());
+}
+
+#[test]
+fn huge_size() {
+    let data = [0; 32 * 1024];
+
+    let mut framed = FramedRead::new(&data[..], BigDecoder);
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+
+    struct BigDecoder;
+
+    impl Decoder for BigDecoder {
+        type Item = u32;
+        type Error = io::Error;
+
+        fn decode(&mut self, buf: &mut BytesMut) -> io::Result<Option<u32>> {
+            if buf.len() < 32 * 1024 {
+                return Ok(None);
+            }
+            buf.split_to(32 * 1024);
+            Ok(Some(0))
+        }
+    }
+}
+
+#[test]
+fn data_remaining_is_error() {
+    let data = [0; 5];
+
+    let mut framed = FramedRead::new(&data[..], U32Decoder);
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert!(framed.poll().is_err());
+}
+
+#[test]
+fn multi_frames_on_eof() {
+    struct MyDecoder(Vec<u32>);
+
+    impl Decoder for MyDecoder {
+        type Item = u32;
+        type Error = io::Error;
+
+        fn decode(&mut self, _buf: &mut BytesMut) -> io::Result<Option<u32>> {
+            unreachable!();
+        }
+
+        fn decode_eof(&mut self, _buf: &mut BytesMut) -> io::Result<Option<u32>> {
+            if self.0.is_empty() {
+                return Ok(None);
+            }
+
+            Ok(Some(self.0.remove(0)))
+        }
+    }
+
+    let mut framed = FramedRead::new(mock!(), MyDecoder(vec![0, 1, 2, 3]));
+    assert_eq!(Ready(Some(0)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(1)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(2)), framed.poll().unwrap());
+    assert_eq!(Ready(Some(3)), framed.poll().unwrap());
+    assert_eq!(Ready(None), framed.poll().unwrap());
+}
+
+// ===== Mock ======
+
+struct Mock {
+    calls: VecDeque<io::Result<Vec<u8>>>,
+}
+
+impl Read for Mock {
+    fn read(&mut self, dst: &mut [u8]) -> io::Result<usize> {
+        match self.calls.pop_front() {
+            Some(Ok(data)) => {
+                debug_assert!(dst.len() >= data.len());
+                dst[..data.len()].copy_from_slice(&data[..]);
+                Ok(data.len())
+            }
+            Some(Err(e)) => Err(e),
+            None => Ok(0),
+        }
+    }
+}
+
+impl AsyncRead for Mock {
+}

tokio-codec/tests/framed_write.rs

@@ -0,0 +1,134 @@
+extern crate tokio_codec;
+extern crate tokio_io;
+extern crate bytes;
+extern crate futures;
+
+use tokio_io::AsyncWrite;
+use tokio_codec::{Encoder, FramedWrite};
+
+use futures::{Sink, Poll};
+use bytes::{BytesMut, BufMut, BigEndian};
+
+use std::io::{self, Write};
+use std::collections::VecDeque;
+
+macro_rules! mock {
+    ($($x:expr,)*) => {{
+        let mut v = VecDeque::new();
+        v.extend(vec![$($x),*]);
+        Mock { calls: v }
+    }};
+}
+
+struct U32Encoder;
+
+impl Encoder for U32Encoder {
+    type Item = u32;
+    type Error = io::Error;
+
+    fn encode(&mut self, item: u32, dst: &mut BytesMut) -> io::Result<()> {
+        // Reserve space
+        dst.reserve(4);
+        dst.put_u32_be(item);
+        Ok(())
+    }
+}
+
+#[test]
+fn write_multi_frame_in_packet() {
+    let mock = mock! {
+        Ok(b"\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02".to_vec()),
+    };
+
+    let mut framed = FramedWrite::new(mock, U32Encoder);
+    assert!(framed.start_send(0).unwrap().is_ready());
+    assert!(framed.start_send(1).unwrap().is_ready());
+    assert!(framed.start_send(2).unwrap().is_ready());
+
+    // Nothing written yet
+    assert_eq!(1, framed.get_ref().calls.len());
+
+    // Flush the writes
+    assert!(framed.poll_complete().unwrap().is_ready());
+
+    assert_eq!(0, framed.get_ref().calls.len());
+}
+
+#[test]
+fn write_hits_backpressure() {
+    const ITER: usize = 2 * 1024;
+
+    let mut mock = mock! {
+        // Block the `ITER`th write
+        Err(io::Error::new(io::ErrorKind::WouldBlock, "not ready")),
+        Ok(b"".to_vec()),
+    };
+
+    for i in 0..(ITER + 1) {
+        let mut b = BytesMut::with_capacity(4);
+        b.put_u32_be(i as u32);
+
+        // Append to the end
+        match mock.calls.back_mut().unwrap() {
+            &mut Ok(ref mut data) => {
+                // Write in 2kb chunks
+                if data.len() < ITER {
+                    data.extend_from_slice(&b[..]);
+                    continue;
+                }
+            }
+            _ => unreachable!(),
+        }
+
+        // Push a new new chunk
+        mock.calls.push_back(Ok(b[..].to_vec()));
+    }
+
+    let mut framed = FramedWrite::new(mock, U32Encoder);
+
+    for i in 0..ITER {
+        assert!(framed.start_send(i as u32).unwrap().is_ready());
+    }
+
+    // This should reject
+    assert!(!framed.start_send(ITER as u32).unwrap().is_ready());
+
+    // This should succeed and start flushing the buffer.
+    assert!(framed.start_send(ITER as u32).unwrap().is_ready());
+
+    // Flush the rest of the buffer
+    assert!(framed.poll_complete().unwrap().is_ready());
+
+    // Ensure the mock is empty
+    assert_eq!(0, framed.get_ref().calls.len());
+}
+
+// ===== Mock ======
+
+struct Mock {
+    calls: VecDeque<io::Result<Vec<u8>>>,
+}
+
+impl Write for Mock {
+    fn write(&mut self, src: &[u8]) -> io::Result<usize> {
+        match self.calls.pop_front() {
+            Some(Ok(data)) => {
+                assert!(src.len() >= data.len());
+                assert_eq!(&data[..], &src[..data.len()]);
+                Ok(data.len())
+            }
+            Some(Err(e)) => Err(e),
+            None => panic!("unexpected write; {:?}", src),
+        }
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+impl AsyncWrite for Mock {
+    fn shutdown(&mut self) -> Poll<(), io::Error> {
+        Ok(().into())
+    }
+}