add support for tokio & improve net crate api

3 files changed, 380 insertions, 0 deletions

diff --git a/net/src/stream/buffer.rs b/net/src/stream/buffer.rs
new file mode 100644
index 0000000..f211600
--- /dev/null
+++ b/net/src/stream/buffer.rs
@@ -0,0 +1,82 @@
+#[derive(Debug)]
+pub struct Buffer<B> {
+    inner: B,
+    len: usize,
+    cap: usize,
+}
+
+impl<B> Buffer<B>
+where
+    B: AsMut<[u8]> + AsRef<[u8]>,
+{
+    /// Constructs a new, empty Buffer<B>.
+    pub fn new(b: B) -> Self {
+        Self {
+            cap: b.as_ref().len(),
+            inner: b,
+            len: 0,
+        }
+    }
+
+    /// Returns the number of elements in the buffer.
+    #[allow(dead_code)]
+    pub fn len(&self) -> usize {
+        self.len
+    }
+
+    /// Resizes the buffer in-place so that `len` is equal to `new_size`.
+    pub fn resize(&mut self, new_size: usize) {
+        assert!(self.cap > new_size);
+        self.len = new_size;
+    }
+
+    /// Appends all elements in a slice to the buffer.
+    pub fn extend_from_slice(&mut self, bytes: &[u8]) {
+        let old_len = self.len;
+        self.resize(self.len + bytes.len());
+        self.inner.as_mut()[old_len..bytes.len() + old_len].copy_from_slice(bytes);
+    }
+
+    /// Shortens the buffer, dropping the first `cnt` bytes and keeping the
+    /// rest.
+    pub fn advance(&mut self, cnt: usize) {
+        assert!(self.len >= cnt);
+        self.inner.as_mut().rotate_left(cnt);
+        self.resize(self.len - cnt);
+    }
+
+    /// Returns `true` if the buffer contains no elements.
+    pub fn is_empty(&self) -> bool {
+        self.len == 0
+    }
+}
+
+impl<B> AsMut<[u8]> for Buffer<B>
+where
+    B: AsMut<[u8]> + AsRef<[u8]>,
+{
+    fn as_mut(&mut self) -> &mut [u8] {
+        &mut self.inner.as_mut()[..self.len]
+    }
+}
+
+impl<B> AsRef<[u8]> for Buffer<B>
+where
+    B: AsMut<[u8]> + AsRef<[u8]>,
+{
+    fn as_ref(&self) -> &[u8] {
+        &self.inner.as_ref()[..self.len]
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_buffer_advance() {
+        let mut buf = Buffer::new([0u8; 32]);
+        buf.extend_from_slice(&[1, 2, 3]);
+        assert_eq!([1, 2, 3], buf.as_ref());
+    }
+}
diff --git a/net/src/stream/mod.rs b/net/src/stream/mod.rs
new file mode 100644
index 0000000..9493b29
--- /dev/null
+++ b/net/src/stream/mod.rs
@@ -0,0 +1,191 @@
+mod buffer;
+mod websocket;
+
+pub use websocket::WsStream;
+
+use std::{
+    io::ErrorKind,
+    pin::Pin,
+    task::{Context, Poll},
+};
+
+use futures_util::{
+    ready,
+    stream::{Stream, StreamExt},
+    Sink,
+};
+use pin_project_lite::pin_project;
+
+use karyon_core::async_runtime::io::{AsyncRead, AsyncWrite};
+
+use crate::{
+    codec::{Decoder, Encoder},
+    Error, Result,
+};
+
+use buffer::Buffer;
+
+const BUFFER_SIZE: usize = 2048 * 2024; // 4MB
+const INITIAL_BUFFER_SIZE: usize = 1024 * 1024; // 1MB
+
+pub struct ReadStream<T, C> {
+    inner: T,
+    decoder: C,
+    buffer: Buffer<[u8; BUFFER_SIZE]>,
+}
+
+impl<T, C> ReadStream<T, C>
+where
+    T: AsyncRead + Unpin,
+    C: Decoder + Unpin,
+{
+    pub fn new(inner: T, decoder: C) -> Self {
+        Self {
+            inner,
+            decoder,
+            buffer: Buffer::new([0u8; BUFFER_SIZE]),
+        }
+    }
+
+    pub async fn recv(&mut self) -> Result<C::DeItem> {
+        match self.next().await {
+            Some(m) => m,
+            None => Err(Error::IO(std::io::ErrorKind::ConnectionAborted.into())),
+        }
+    }
+}
+
+pin_project! {
+    pub struct WriteStream<T, C> {
+        #[pin]
+        inner: T,
+        encoder: C,
+        high_water_mark: usize,
+        buffer: Buffer<[u8; BUFFER_SIZE]>,
+    }
+}
+
+impl<T, C> WriteStream<T, C>
+where
+    T: AsyncWrite + Unpin,
+    C: Encoder + Unpin,
+{
+    pub fn new(inner: T, encoder: C) -> Self {
+        Self {
+            inner,
+            encoder,
+            high_water_mark: 131072,
+            buffer: Buffer::new([0u8; BUFFER_SIZE]),
+        }
+    }
+}
+
+impl<T, C> Stream for ReadStream<T, C>
+where
+    T: AsyncRead + Unpin,
+    C: Decoder + Unpin,
+{
+    type Item = Result<C::DeItem>;
+
+    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        let this = &mut *self;
+
+        if let Some((n, item)) = this.decoder.decode(this.buffer.as_mut())? {
+            this.buffer.advance(n);
+            return Poll::Ready(Some(Ok(item)));
+        }
+
+        let mut buf = [0u8; INITIAL_BUFFER_SIZE];
+        #[cfg(feature = "tokio")]
+        let mut buf = tokio::io::ReadBuf::new(&mut buf);
+
+        loop {
+            #[cfg(feature = "smol")]
+            let n = ready!(Pin::new(&mut this.inner).poll_read(cx, &mut buf))?;
+            #[cfg(feature = "smol")]
+            let bytes = &buf[..n];
+
+            #[cfg(feature = "tokio")]
+            ready!(Pin::new(&mut this.inner).poll_read(cx, &mut buf))?;
+            #[cfg(feature = "tokio")]
+            let bytes = buf.filled();
+            #[cfg(feature = "tokio")]
+            let n = bytes.len();
+
+            this.buffer.extend_from_slice(bytes);
+
+            match this.decoder.decode(this.buffer.as_mut())? {
+                Some((cn, item)) => {
+                    this.buffer.advance(cn);
+                    return Poll::Ready(Some(Ok(item)));
+                }
+                None if n == 0 => {
+                    if this.buffer.is_empty() {
+                        return Poll::Ready(None);
+                    } else {
+                        return Poll::Ready(Some(Err(std::io::Error::new(
+                            std::io::ErrorKind::UnexpectedEof,
+                            "bytes remaining in read stream",
+                        )
+                        .into())));
+                    }
+                }
+                _ => continue,
+            }
+        }
+    }
+}
+
+impl<T, C> Sink<C::EnItem> for WriteStream<T, C>
+where
+    T: AsyncWrite + Unpin,
+    C: Encoder + Unpin,
+{
+    type Error = Error;
+
+    fn poll_ready(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>> {
+        let this = &mut *self;
+        while !this.buffer.is_empty() {
+            let n = ready!(Pin::new(&mut this.inner).poll_write(cx, this.buffer.as_ref()))?;
+
+            if n == 0 {
+                return Poll::Ready(Err(std::io::Error::new(
+                    ErrorKind::UnexpectedEof,
+                    "End of file",
+                )
+                .into()));
+            }
+
+            this.buffer.advance(n);
+        }
+
+        Poll::Ready(Ok(()))
+    }
+
+    fn start_send(mut self: Pin<&mut Self>, item: C::EnItem) -> Result<()> {
+        let this = &mut *self;
+        let mut buf = [0u8; INITIAL_BUFFER_SIZE];
+        let n = this.encoder.encode(&item, &mut buf)?;
+        this.buffer.extend_from_slice(&buf[..n]);
+        Ok(())
+    }
+
+    fn poll_flush(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context,
+    ) -> Poll<std::result::Result<(), Self::Error>> {
+        ready!(self.as_mut().poll_ready(cx))?;
+        self.project().inner.poll_flush(cx).map_err(Into::into)
+    }
+
+    fn poll_close(
+        mut self: Pin<&mut Self>,
+        cx: &mut Context,
+    ) -> Poll<std::result::Result<(), Self::Error>> {
+        ready!(self.as_mut().poll_flush(cx))?;
+        #[cfg(feature = "smol")]
+        return self.project().inner.poll_close(cx).map_err(Error::from);
+        #[cfg(feature = "tokio")]
+        return self.project().inner.poll_shutdown(cx).map_err(Error::from);
+    }
+}
diff --git a/net/src/stream/websocket.rs b/net/src/stream/websocket.rs
new file mode 100644
index 0000000..2552eaf
--- /dev/null
+++ b/net/src/stream/websocket.rs
@@ -0,0 +1,107 @@
+use std::{
+    pin::Pin,
+    task::{Context, Poll},
+};
+
+use async_tungstenite::tungstenite::Message;
+use futures_util::{Sink, SinkExt, Stream, StreamExt};
+
+#[cfg(feature = "smol")]
+use futures_rustls::TlsStream;
+#[cfg(feature = "tokio")]
+use tokio_rustls::TlsStream;
+
+use karyon_core::async_runtime::net::TcpStream;
+
+use crate::{codec::WebSocketCodec, Error, Result};
+
+#[cfg(feature = "tokio")]
+type WebSocketStream<T> =
+    async_tungstenite::WebSocketStream<async_tungstenite::tokio::TokioAdapter<T>>;
+#[cfg(feature = "smol")]
+use async_tungstenite::WebSocketStream;
+
+pub struct WsStream<C> {
+    inner: InnerWSConn,
+    codec: C,
+}
+
+impl<C> WsStream<C>
+where
+    C: WebSocketCodec,
+{
+    pub fn new_ws(conn: WebSocketStream<TcpStream>, codec: C) -> Self {
+        Self {
+            inner: InnerWSConn::Plain(conn),
+            codec,
+        }
+    }
+
+    pub fn new_wss(conn: WebSocketStream<TlsStream<TcpStream>>, codec: C) -> Self {
+        Self {
+            inner: InnerWSConn::Tls(conn),
+            codec,
+        }
+    }
+
+    pub async fn recv(&mut self) -> Result<C::Item> {
+        match self.inner.next().await {
+            Some(msg) => self.codec.decode(&msg?),
+            None => Err(Error::IO(std::io::ErrorKind::ConnectionAborted.into())),
+        }
+    }
+
+    pub async fn send(&mut self, msg: C::Item) -> Result<()> {
+        let ws_msg = self.codec.encode(&msg)?;
+        self.inner.send(ws_msg).await
+    }
+}
+
+enum InnerWSConn {
+    Plain(WebSocketStream<TcpStream>),
+    Tls(WebSocketStream<TlsStream<TcpStream>>),
+}
+
+impl Sink<Message> for InnerWSConn {
+    type Error = Error;
+
+    fn poll_ready(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+        match &mut *self {
+            InnerWSConn::Plain(s) => Pin::new(s).poll_ready(cx).map_err(Error::from),
+            InnerWSConn::Tls(s) => Pin::new(s).poll_ready(cx).map_err(Error::from),
+        }
+    }
+
+    fn start_send(mut self: Pin<&mut Self>, item: Message) -> Result<()> {
+        match &mut *self {
+            InnerWSConn::Plain(s) => Pin::new(s).start_send(item).map_err(Error::from),
+            InnerWSConn::Tls(s) => Pin::new(s).start_send(item).map_err(Error::from),
+        }
+    }
+
+    fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+        match &mut *self {
+            InnerWSConn::Plain(s) => Pin::new(s).poll_flush(cx).map_err(Error::from),
+            InnerWSConn::Tls(s) => Pin::new(s).poll_flush(cx).map_err(Error::from),
+        }
+    }
+
+    fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+        match &mut *self {
+            InnerWSConn::Plain(s) => Pin::new(s).poll_close(cx).map_err(Error::from),
+            InnerWSConn::Tls(s) => Pin::new(s).poll_close(cx).map_err(Error::from),
+        }
+        .map_err(Error::from)
+    }
+}
+
+impl Stream for InnerWSConn {
+    type Item = Result<Message>;
+
+    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        match &mut *self {
+            InnerWSConn::Plain(s) => Pin::new(s).poll_next(cx).map_err(Error::from),
+            InnerWSConn::Tls(s) => Pin::new(s).poll_next(cx).map_err(Error::from),
+        }
+    }
+}