1 files changed, 439 insertions, 0 deletions
diff --git a/third_party/rust/hyper/src/proto/h1/encode.rs b/third_party/rust/hyper/src/proto/h1/encode.rs
new file mode 100644
index 0000000000..f0aa261a4f
--- /dev/null
+++ b/third_party/rust/hyper/src/proto/h1/encode.rs
@@ -0,0 +1,439 @@
+use std::fmt;
+use std::io::IoSlice;
+
+use bytes::buf::{Chain, Take};
+use bytes::Buf;
+use tracing::trace;
+
+use super::io::WriteBuf;
+
+type StaticBuf = &'static [u8];
+
+/// Encoders to handle different Transfer-Encodings.
+#[derive(Debug, Clone, PartialEq)]
+pub(crate) struct Encoder {
+    kind: Kind,
+    is_last: bool,
+}
+
+#[derive(Debug)]
+pub(crate) struct EncodedBuf<B> {
+    kind: BufKind<B>,
+}
+
+#[derive(Debug)]
+pub(crate) struct NotEof(u64);
+
+#[derive(Debug, PartialEq, Clone)]
+enum Kind {
+    /// An Encoder for when Transfer-Encoding includes `chunked`.
+    Chunked,
+    /// An Encoder for when Content-Length is set.
+    ///
+    /// Enforces that the body is not longer than the Content-Length header.
+    Length(u64),
+    /// An Encoder for when neither Content-Length nor Chunked encoding is set.
+    ///
+    /// This is mostly only used with HTTP/1.0 with a length. This kind requires
+    /// the connection to be closed when the body is finished.
+    #[cfg(feature = "server")]
+    CloseDelimited,
+}
+
+#[derive(Debug)]
+enum BufKind<B> {
+    Exact(B),
+    Limited(Take<B>),
+    Chunked(Chain<Chain<ChunkSize, B>, StaticBuf>),
+    ChunkedEnd(StaticBuf),
+}
+
+impl Encoder {
+    fn new(kind: Kind) -> Encoder {
+        Encoder {
+            kind,
+            is_last: false,
+        }
+    }
+    pub(crate) fn chunked() -> Encoder {
+        Encoder::new(Kind::Chunked)
+    }
+
+    pub(crate) fn length(len: u64) -> Encoder {
+        Encoder::new(Kind::Length(len))
+    }
+
+    #[cfg(feature = "server")]
+    pub(crate) fn close_delimited() -> Encoder {
+        Encoder::new(Kind::CloseDelimited)
+    }
+
+    pub(crate) fn is_eof(&self) -> bool {
+        matches!(self.kind, Kind::Length(0))
+    }
+
+    #[cfg(feature = "server")]
+    pub(crate) fn set_last(mut self, is_last: bool) -> Self {
+        self.is_last = is_last;
+        self
+    }
+
+    pub(crate) fn is_last(&self) -> bool {
+        self.is_last
+    }
+
+    pub(crate) fn is_close_delimited(&self) -> bool {
+        match self.kind {
+            #[cfg(feature = "server")]
+            Kind::CloseDelimited => true,
+            _ => false,
+        }
+    }
+
+    pub(crate) fn end<B>(&self) -> Result<Option<EncodedBuf<B>>, NotEof> {
+        match self.kind {
+            Kind::Length(0) => Ok(None),
+            Kind::Chunked => Ok(Some(EncodedBuf {
+                kind: BufKind::ChunkedEnd(b"0\r\n\r\n"),
+            })),
+            #[cfg(feature = "server")]
+            Kind::CloseDelimited => Ok(None),
+            Kind::Length(n) => Err(NotEof(n)),
+        }
+    }
+
+    pub(crate) fn encode<B>(&mut self, msg: B) -> EncodedBuf<B>
+    where
+        B: Buf,
+    {
+        let len = msg.remaining();
+        debug_assert!(len > 0, "encode() called with empty buf");
+
+        let kind = match self.kind {
+            Kind::Chunked => {
+                trace!("encoding chunked {}B", len);
+                let buf = ChunkSize::new(len)
+                    .chain(msg)
+                    .chain(b"\r\n" as &'static [u8]);
+                BufKind::Chunked(buf)
+            }
+            Kind::Length(ref mut remaining) => {
+                trace!("sized write, len = {}", len);
+                if len as u64 > *remaining {
+                    let limit = *remaining as usize;
+                    *remaining = 0;
+                    BufKind::Limited(msg.take(limit))
+                } else {
+                    *remaining -= len as u64;
+                    BufKind::Exact(msg)
+                }
+            }
+            #[cfg(feature = "server")]
+            Kind::CloseDelimited => {
+                trace!("close delimited write {}B", len);
+                BufKind::Exact(msg)
+            }
+        };
+        EncodedBuf { kind }
+    }
+
+    pub(super) fn encode_and_end<B>(&self, msg: B, dst: &mut WriteBuf<EncodedBuf<B>>) -> bool
+    where
+        B: Buf,
+    {
+        let len = msg.remaining();
+        debug_assert!(len > 0, "encode() called with empty buf");
+
+        match self.kind {
+            Kind::Chunked => {
+                trace!("encoding chunked {}B", len);
+                let buf = ChunkSize::new(len)
+                    .chain(msg)
+                    .chain(b"\r\n0\r\n\r\n" as &'static [u8]);
+                dst.buffer(buf);
+                !self.is_last
+            }
+            Kind::Length(remaining) => {
+                use std::cmp::Ordering;
+
+                trace!("sized write, len = {}", len);
+                match (len as u64).cmp(&remaining) {
+                    Ordering::Equal => {
+                        dst.buffer(msg);
+                        !self.is_last
+                    }
+                    Ordering::Greater => {
+                        dst.buffer(msg.take(remaining as usize));
+                        !self.is_last
+                    }
+                    Ordering::Less => {
+                        dst.buffer(msg);
+                        false
+                    }
+                }
+            }
+            #[cfg(feature = "server")]
+            Kind::CloseDelimited => {
+                trace!("close delimited write {}B", len);
+                dst.buffer(msg);
+                false
+            }
+        }
+    }
+
+    /// Encodes the full body, without verifying the remaining length matches.
+    ///
+    /// This is used in conjunction with HttpBody::__hyper_full_data(), which
+    /// means we can trust that the buf has the correct size (the buf itself
+    /// was checked to make the headers).
+    pub(super) fn danger_full_buf<B>(self, msg: B, dst: &mut WriteBuf<EncodedBuf<B>>)
+    where
+        B: Buf,
+    {
+        debug_assert!(msg.remaining() > 0, "encode() called with empty buf");
+        debug_assert!(
+            match self.kind {
+                Kind::Length(len) => len == msg.remaining() as u64,
+                _ => true,
+            },
+            "danger_full_buf length mismatches"
+        );
+
+        match self.kind {
+            Kind::Chunked => {
+                let len = msg.remaining();
+                trace!("encoding chunked {}B", len);
+                let buf = ChunkSize::new(len)
+                    .chain(msg)
+                    .chain(b"\r\n0\r\n\r\n" as &'static [u8]);
+                dst.buffer(buf);
+            }
+            _ => {
+                dst.buffer(msg);
+            }
+        }
+    }
+}
+
+impl<B> Buf for EncodedBuf<B>
+where
+    B: Buf,
+{
+    #[inline]
+    fn remaining(&self) -> usize {
+        match self.kind {
+            BufKind::Exact(ref b) => b.remaining(),
+            BufKind::Limited(ref b) => b.remaining(),
+            BufKind::Chunked(ref b) => b.remaining(),
+            BufKind::ChunkedEnd(ref b) => b.remaining(),
+        }
+    }
+
+    #[inline]
+    fn chunk(&self) -> &[u8] {
+        match self.kind {
+            BufKind::Exact(ref b) => b.chunk(),
+            BufKind::Limited(ref b) => b.chunk(),
+            BufKind::Chunked(ref b) => b.chunk(),
+            BufKind::ChunkedEnd(ref b) => b.chunk(),
+        }
+    }
+
+    #[inline]
+    fn advance(&mut self, cnt: usize) {
+        match self.kind {
+            BufKind::Exact(ref mut b) => b.advance(cnt),
+            BufKind::Limited(ref mut b) => b.advance(cnt),
+            BufKind::Chunked(ref mut b) => b.advance(cnt),
+            BufKind::ChunkedEnd(ref mut b) => b.advance(cnt),
+        }
+    }
+
+    #[inline]
+    fn chunks_vectored<'t>(&'t self, dst: &mut [IoSlice<'t>]) -> usize {
+        match self.kind {
+            BufKind::Exact(ref b) => b.chunks_vectored(dst),
+            BufKind::Limited(ref b) => b.chunks_vectored(dst),
+            BufKind::Chunked(ref b) => b.chunks_vectored(dst),
+            BufKind::ChunkedEnd(ref b) => b.chunks_vectored(dst),
+        }
+    }
+}
+
+#[cfg(target_pointer_width = "32")]
+const USIZE_BYTES: usize = 4;
+
+#[cfg(target_pointer_width = "64")]
+const USIZE_BYTES: usize = 8;
+
+// each byte will become 2 hex
+const CHUNK_SIZE_MAX_BYTES: usize = USIZE_BYTES * 2;
+
+#[derive(Clone, Copy)]
+struct ChunkSize {
+    bytes: [u8; CHUNK_SIZE_MAX_BYTES + 2],
+    pos: u8,
+    len: u8,
+}
+
+impl ChunkSize {
+    fn new(len: usize) -> ChunkSize {
+        use std::fmt::Write;
+        let mut size = ChunkSize {
+            bytes: [0; CHUNK_SIZE_MAX_BYTES + 2],
+            pos: 0,
+            len: 0,
+        };
+        write!(&mut size, "{:X}\r\n", len).expect("CHUNK_SIZE_MAX_BYTES should fit any usize");
+        size
+    }
+}
+
+impl Buf for ChunkSize {
+    #[inline]
+    fn remaining(&self) -> usize {
+        (self.len - self.pos).into()
+    }
+
+    #[inline]
+    fn chunk(&self) -> &[u8] {
+        &self.bytes[self.pos.into()..self.len.into()]
+    }
+
+    #[inline]
+    fn advance(&mut self, cnt: usize) {
+        assert!(cnt <= self.remaining());
+        self.pos += cnt as u8; // just asserted cnt fits in u8
+    }
+}
+
+impl fmt::Debug for ChunkSize {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("ChunkSize")
+            .field("bytes", &&self.bytes[..self.len.into()])
+            .field("pos", &self.pos)
+            .finish()
+    }
+}
+
+impl fmt::Write for ChunkSize {
+    fn write_str(&mut self, num: &str) -> fmt::Result {
+        use std::io::Write;
+        (&mut self.bytes[self.len.into()..])
+            .write_all(num.as_bytes())
+            .expect("&mut [u8].write() cannot error");
+        self.len += num.len() as u8; // safe because bytes is never bigger than 256
+        Ok(())
+    }
+}
+
+impl<B: Buf> From<B> for EncodedBuf<B> {
+    fn from(buf: B) -> Self {
+        EncodedBuf {
+            kind: BufKind::Exact(buf),
+        }
+    }
+}
+
+impl<B: Buf> From<Take<B>> for EncodedBuf<B> {
+    fn from(buf: Take<B>) -> Self {
+        EncodedBuf {
+            kind: BufKind::Limited(buf),
+        }
+    }
+}
+
+impl<B: Buf> From<Chain<Chain<ChunkSize, B>, StaticBuf>> for EncodedBuf<B> {
+    fn from(buf: Chain<Chain<ChunkSize, B>, StaticBuf>) -> Self {
+        EncodedBuf {
+            kind: BufKind::Chunked(buf),
+        }
+    }
+}
+
+impl fmt::Display for NotEof {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "early end, expected {} more bytes", self.0)
+    }
+}
+
+impl std::error::Error for NotEof {}
+
+#[cfg(test)]
+mod tests {
+    use bytes::BufMut;
+
+    use super::super::io::Cursor;
+    use super::Encoder;
+
+    #[test]
+    fn chunked() {
+        let mut encoder = Encoder::chunked();
+        let mut dst = Vec::new();
+
+        let msg1 = b"foo bar".as_ref();
+        let buf1 = encoder.encode(msg1);
+        dst.put(buf1);
+        assert_eq!(dst, b"7\r\nfoo bar\r\n");
+
+        let msg2 = b"baz quux herp".as_ref();
+        let buf2 = encoder.encode(msg2);
+        dst.put(buf2);
+
+        assert_eq!(dst, b"7\r\nfoo bar\r\nD\r\nbaz quux herp\r\n");
+
+        let end = encoder.end::<Cursor<Vec<u8>>>().unwrap().unwrap();
+        dst.put(end);
+
+        assert_eq!(
+            dst,
+            b"7\r\nfoo bar\r\nD\r\nbaz quux herp\r\n0\r\n\r\n".as_ref()
+        );
+    }
+
+    #[test]
+    fn length() {
+        let max_len = 8;
+        let mut encoder = Encoder::length(max_len as u64);
+        let mut dst = Vec::new();
+
+        let msg1 = b"foo bar".as_ref();
+        let buf1 = encoder.encode(msg1);
+        dst.put(buf1);
+
+        assert_eq!(dst, b"foo bar");
+        assert!(!encoder.is_eof());
+        encoder.end::<()>().unwrap_err();
+
+        let msg2 = b"baz".as_ref();
+        let buf2 = encoder.encode(msg2);
+        dst.put(buf2);
+
+        assert_eq!(dst.len(), max_len);
+        assert_eq!(dst, b"foo barb");
+        assert!(encoder.is_eof());
+        assert!(encoder.end::<()>().unwrap().is_none());
+    }
+
+    #[test]
+    fn eof() {
+        let mut encoder = Encoder::close_delimited();
+        let mut dst = Vec::new();
+
+        let msg1 = b"foo bar".as_ref();
+        let buf1 = encoder.encode(msg1);
+        dst.put(buf1);
+
+        assert_eq!(dst, b"foo bar");
+        assert!(!encoder.is_eof());
+        encoder.end::<()>().unwrap();
+
+        let msg2 = b"baz".as_ref();
+        let buf2 = encoder.encode(msg2);
+        dst.put(buf2);
+
+        assert_eq!(dst, b"foo barbaz");
+        assert!(!encoder.is_eof());
+        encoder.end::<()>().unwrap();
+    }
+}