Replace `InputBuffer` with a faster alternative

We're also deprecating the usage of `input_buffer` crate, see:
https://github.com/snapview/input_buffer/issues/6#issuecomment-870548303

Cargo.toml

@@ -27,7 +27,6 @@ byteorder = "1.3.2"
 bytes = "1.0"
 http = "0.2"
 httparse = "1.3.4"
-input_buffer = "0.4.0"
 log = "0.4.8"
 rand = "0.8.0"
 sha-1 = "0.9"
@@ -53,5 +52,6 @@ optional = true
 version = "0.5.0"
 
 [dev-dependencies]
+input_buffer = "0.5.0"
 env_logger = "0.8.1"
 net2 = "0.2.33"

src/buffer.rs

@@ -0,0 +1,111 @@
+//! A buffer for reading data from the network.
+//!
+//! The `ReadBuffer` is a buffer of bytes similar to a first-in, first-out queue.
+//! It is filled by reading from a stream supporting `Read` and is then
+//! accessible as a cursor for reading bytes.
+
+use std::io::{Cursor, Read, Result as IoResult};
+
+use bytes::Buf;
+
+/// A FIFO buffer for reading packets from the network.
+#[derive(Debug)]
+pub struct ReadBuffer<const CHUNK_SIZE: usize> {
+    storage: Cursor<Vec<u8>>,
+    chunk: [u8; CHUNK_SIZE],
+}
+
+impl<const CHUNK_SIZE: usize> ReadBuffer<CHUNK_SIZE> {
+    /// Create a new empty input buffer.
+    pub fn new() -> Self {
+        Self::with_capacity(CHUNK_SIZE)
+    }
+
+    /// Create a new empty input buffer with a given `capacity`.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self::from_partially_read(Vec::with_capacity(capacity))
+    }
+
+    /// Create a input buffer filled with previously read data.
+    pub fn from_partially_read(part: Vec<u8>) -> Self {
+        Self { storage: Cursor::new(part), chunk: [0; CHUNK_SIZE] }
+    }
+
+    /// Get a cursor to the data storage.
+    pub fn as_cursor(&self) -> &Cursor<Vec<u8>> {
+        &self.storage
+    }
+
+    /// Get a cursor to the mutable data storage.
+    pub fn as_cursor_mut(&mut self) -> &mut Cursor<Vec<u8>> {
+        &mut self.storage
+    }
+
+    /// Consume the `ReadBuffer` and get the internal storage.
+    pub fn into_vec(mut self) -> Vec<u8> {
+        // Current implementation of `tungstenite-rs` expects that the `into_vec()` drains
+        // the data from the container that has already been read by the cursor.
+        let pos = self.storage.position() as usize;
+        self.storage.get_mut().drain(0..pos).count();
+        self.storage.set_position(0);
+
+        // Now we can safely return the internal container.
+        self.storage.into_inner()
+    }
+
+    /// Read next portion of data from the given input stream.
+    pub fn read_from<S: Read>(&mut self, stream: &mut S) -> IoResult<usize> {
+        let size = stream.read(&mut self.chunk)?;
+        self.storage.get_mut().extend_from_slice(&self.chunk[..size]);
+        Ok(size)
+    }
+}
+
+impl<const CHUNK_SIZE: usize> Buf for ReadBuffer<CHUNK_SIZE> {
+    fn remaining(&self) -> usize {
+        Buf::remaining(self.as_cursor())
+    }
+
+    fn chunk(&self) -> &[u8] {
+        Buf::chunk(self.as_cursor())
+    }
+
+    fn advance(&mut self, cnt: usize) {
+        Buf::advance(self.as_cursor_mut(), cnt)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn simple_reading() {
+        let mut input = Cursor::new(b"Hello World!".to_vec());
+        let mut buffer = ReadBuffer::<4096>::new();
+        let size = buffer.read_from(&mut input).unwrap();
+        assert_eq!(size, 12);
+        assert_eq!(buffer.chunk(), b"Hello World!");
+    }
+
+    #[test]
+    fn reading_in_chunks() {
+        let mut inp = Cursor::new(b"Hello World!".to_vec());
+        let mut buf = ReadBuffer::<4>::new();
+
+        let size = buf.read_from(&mut inp).unwrap();
+        assert_eq!(size, 4);
+        assert_eq!(buf.chunk(), b"Hell");
+
+        buf.advance(2);
+        assert_eq!(buf.chunk(), b"ll");
+
+        let size = buf.read_from(&mut inp).unwrap();
+        assert_eq!(size, 4);
+        assert_eq!(buf.chunk(), b"llo Wo");
+
+        let size = buf.read_from(&mut inp).unwrap();
+        assert_eq!(size, 4);
+        assert_eq!(buf.chunk(), b"llo World!");
+    }
+}

src/client.rs

@@ -72,7 +72,8 @@ mod encryption {
             Mode::Tls => {
                 let config = {
                     let mut config = ClientConfig::new();
-                    config.root_store = rustls_native_certs::load_native_certs().map_err(|(_, err)| err)?;
+                    config.root_store =
+                        rustls_native_certs::load_native_certs().map_err(|(_, err)| err)?;
 
                     Arc::new(config)
                 };

src/error.rs

@@ -127,8 +127,6 @@ pub enum CapacityError {
     #[error("Too many headers")]
     TooManyHeaders,
     /// Received header is too long.
-    #[error("Header too long")]
-    HeaderTooLong,
     /// Message is bigger than the maximum allowed size.
     #[error("Message too long: {size} > {max_size}")]
     MessageTooLong {
@@ -137,9 +135,6 @@ pub enum CapacityError {
         /// The maximum allowed message size.
         max_size: usize,
     },
-    /// TCP buffer is full.
-    #[error("Incoming TCP buffer is full")]
-    TcpBufferFull,
 }
 
 /// Indicates the specific type/cause of a protocol error.

src/handshake/machine.rs

@@ -3,10 +3,10 @@ use log::*;
 use std::io::{Cursor, Read, Write};
 
 use crate::{
-    error::{CapacityError, Error, ProtocolError, Result},
+    error::{Error, ProtocolError, Result},
     util::NonBlockingResult,
+    ReadBuffer,
 };
-use input_buffer::{InputBuffer, MIN_READ};
 
 /// A generic handshake state machine.
 #[derive(Debug)]
@@ -18,10 +18,7 @@ pub struct HandshakeMachine<Stream> {
 impl<Stream> HandshakeMachine<Stream> {
     /// Start reading data from the peer.
     pub fn start_read(stream: Stream) -> Self {
-        HandshakeMachine {
-            stream,
-            state: HandshakeState::Reading(InputBuffer::with_capacity(MIN_READ)),
-        }
+        HandshakeMachine { stream, state: HandshakeState::Reading(ReadBuffer::new()) }
     }
     /// Start writing data to the peer.
     pub fn start_write<D: Into<Vec<u8>>>(stream: Stream, data: D) -> Self {
@@ -43,12 +40,7 @@ impl<Stream: Read + Write> HandshakeMachine<Stream> {
         trace!("Doing handshake round.");
         match self.state {
             HandshakeState::Reading(mut buf) => {
-                let read = buf
-                    .prepare_reserve(MIN_READ)
-                    .with_limit(usize::max_value()) // TODO limit size
-                    .map_err(|_| Error::Capacity(CapacityError::HeaderTooLong))?
-                    .read_from(&mut self.stream)
-                    .no_block()?;
+                let read = buf.read_from(&mut self.stream).no_block()?;
                 match read {
                     Some(0) => Err(Error::Protocol(ProtocolError::HandshakeIncomplete)),
                     Some(_) => Ok(if let Some((size, obj)) = Obj::try_parse(Buf::chunk(&buf))? {
@@ -124,7 +116,7 @@ pub trait TryParse: Sized {
 #[derive(Debug)]
 enum HandshakeState {
     /// Reading data from the peer.
-    Reading(InputBuffer),
+    Reading(ReadBuffer),
     /// Sending data to the peer.
     Writing(Cursor<Vec<u8>>),
 }

src/handshake/mod.rs

@@ -131,9 +131,6 @@ mod tests {
     #[test]
     fn key_conversion() {
         // example from RFC 6455
-        assert_eq!(
-            derive_accept_key(b"dGhlIHNhbXBsZSBub25jZQ=="),
-            "s3pPLMBiTxaQ9kYGzzhZRbK+xOo="
-        );
+        assert_eq!(derive_accept_key(b"dGhlIHNhbXBsZSBub25jZQ=="), "s3pPLMBiTxaQ9kYGzzhZRbK+xOo=");
     }
 }

src/lib.rs

@@ -14,6 +14,7 @@
 
 pub use http;
 
+mod buffer;
 pub mod client;
 pub mod error;
 pub mod handshake;
@@ -22,6 +23,9 @@ pub mod server;
 pub mod stream;
 pub mod util;
 
+const READ_BUFFER_CHUNK_SIZE: usize = 4096;
+type ReadBuffer = buffer::ReadBuffer<READ_BUFFER_CHUNK_SIZE>;
+
 pub use crate::{
     client::{client, connect},
     error::{Error, Result},

src/protocol/frame/mod.rs

@@ -6,12 +6,15 @@ pub mod coding;
 mod frame;
 mod mask;
 
-pub use self::frame::{CloseFrame, Frame, FrameHeader};
+use std::io::{Error as IoError, ErrorKind as IoErrorKind, Read, Write};
 
-use crate::error::{CapacityError, Error, Result};
-use input_buffer::{InputBuffer, MIN_READ};
 use log::*;
-use std::io::{Error as IoError, ErrorKind as IoErrorKind, Read, Write};
+
+pub use self::frame::{CloseFrame, Frame, FrameHeader};
+use crate::{
+    error::{CapacityError, Error, Result},
+    ReadBuffer,
+};
 
 /// A reader and writer for WebSocket frames.
 #[derive(Debug)]
@@ -82,7 +85,7 @@ where
 #[derive(Debug)]
 pub(super) struct FrameCodec {
     /// Buffer to read data from the stream.
-    in_buffer: InputBuffer,
+    in_buffer: ReadBuffer,
     /// Buffer to send packets to the network.
     out_buffer: Vec<u8>,
     /// Header and remaining size of the incoming packet being processed.
@@ -92,17 +95,13 @@ pub(super) struct FrameCodec {
 impl FrameCodec {
     /// Create a new frame codec.
     pub(super) fn new() -> Self {
-        Self {
-            in_buffer: InputBuffer::with_capacity(MIN_READ),
-            out_buffer: Vec::new(),
-            header: None,
-        }
+        Self { in_buffer: ReadBuffer::new(), out_buffer: Vec::new(), header: None }
     }
 
     /// Create a new frame codec from partially read data.
     pub(super) fn from_partially_read(part: Vec<u8>) -> Self {
         Self {
-            in_buffer: InputBuffer::from_partially_read(part),
+            in_buffer: ReadBuffer::from_partially_read(part),
             out_buffer: Vec::new(),
             header: None,
         }
@@ -152,12 +151,7 @@ impl FrameCodec {
             }
 
             // Not enough data in buffer.
-            let size = self
-                .in_buffer
-                .prepare_reserve(MIN_READ)
-                .with_limit(usize::max_value())
-                .map_err(|_| Error::Capacity(CapacityError::TcpBufferFull))?
-                .read_from(stream)?;
+            let size = self.in_buffer.read_from(stream)?;
             if size == 0 {
                 trace!("no frame received");
                 return Ok(None);