From 7dccc512771614d0e54f593edfe77b94bfa5550b Mon Sep 17 00:00:00 2001
From: Alexey Galakhov <agalakhov@snapview.de>
Date: Tue, 31 Jan 2017 19:22:28 +0100
Subject: [PATCH] server: implement server

---
 examples/autobahn-server.rs | 36 +++++++++++++++++++
 src/handshake/server.rs     | 71 ++++++++++++++++++++++++++++++++++++-
 src/lib.rs                  |  1 +
 src/server.rs               |  8 +++++
 4 files changed, 115 insertions(+), 1 deletion(-)
 create mode 100644 examples/autobahn-server.rs
 create mode 100644 src/server.rs

diff --git a/examples/autobahn-server.rs b/examples/autobahn-server.rs
new file mode 100644
index 0000000..8d0ac03
--- /dev/null
+++ b/examples/autobahn-server.rs
@@ -0,0 +1,36 @@
+#[macro_use] extern crate log;
+extern crate env_logger;
+extern crate ws2;
+
+use std::net::{TcpListener, TcpStream};
+use std::thread::spawn;
+
+use ws2::server::accept;
+use ws2::error::Result;
+use ws2::handshake::Handshake;
+
+fn handle_client(stream: TcpStream) -> Result<()> {
+    let mut socket = accept(stream).handshake_wait()?;
+    loop {
+        let msg = socket.read_message()?;
+        socket.write_message(msg)?;
+    }
+}
+
+fn main() {
+    env_logger::init().unwrap();
+
+    let server = TcpListener::bind("127.0.0.1:9001").unwrap();
+
+    for stream in server.incoming() {
+        spawn(move || {
+            match stream {
+                Ok(stream) => match handle_client(stream) {
+                    Ok(_) => (),
+                    Err(e) => warn!("Error in client: {}", e),
+                },
+                Err(e) => warn!("Error accepting stream: {}", e),
+            }
+        });
+    }
+}
diff --git a/src/handshake/server.rs b/src/handshake/server.rs
index 3b3bc7b..dcab055 100644
--- a/src/handshake/server.rs
+++ b/src/handshake/server.rs
@@ -1,9 +1,20 @@
+use std::io::{Cursor, Read, Write};
 use bytes::Buf;
 use httparse;
 use httparse::Status;
 
+use input_buffer::{InputBuffer, MIN_READ};
 use error::{Error, Result};
-use super::{Headers, Httparse, FromHttparse, convert_key, MAX_HEADERS};
+use super::{
+    Handshake,
+    HandshakeResult,
+    Headers,
+    Httparse,
+    FromHttparse,
+    convert_key,
+    MAX_HEADERS
+};
+use protocol::{WebSocket, Role};
 
 /// Request from the client.
 pub struct Request {
@@ -56,6 +67,64 @@ impl<'h, 'b: 'h> FromHttparse<httparse::Request<'h, 'b>> for Request {
     }
 }
 
+/// Server handshake
+pub struct ServerHandshake<Stream> {
+    stream: Stream,
+    state: HandshakeState,
+}
+
+impl<Stream: Read + Write> ServerHandshake<Stream> {
+    /// Start a new server handshake on top of given stream.
+    pub fn new(stream: Stream) -> Self {
+        ServerHandshake {
+            stream: stream,
+            state: HandshakeState::ReceivingRequest(InputBuffer::with_capacity(MIN_READ)),
+        }
+    }
+}
+
+impl<Stream: Read + Write> Handshake for ServerHandshake<Stream> {
+    type Stream = WebSocket<Stream>;
+    fn handshake(mut self) -> Result<HandshakeResult<Self>> {
+        debug!("Performing server handshake...");
+        match self.state {
+            HandshakeState::ReceivingRequest(mut req_buf) => {
+                req_buf.reserve(MIN_READ, usize::max_value())
+                    .map_err(|_| Error::Capacity("Header too long".into()))?;
+                req_buf.read_from(&mut self.stream)?;
+                let state = if let Some(req) = Request::parse(&mut req_buf)? {
+                    let resp = req.reply()?;
+                    HandshakeState::SendingResponse(Cursor::new(resp))
+                } else {
+                    HandshakeState::ReceivingRequest(req_buf)
+                };
+                Ok(HandshakeResult::Incomplete(ServerHandshake {
+                    state: state,
+                    ..self
+                }))
+            }
+            HandshakeState::SendingResponse(mut resp) => {
+                let size = self.stream.write(Buf::bytes(&resp))?;
+                Buf::advance(&mut resp, size);
+                if resp.has_remaining() {
+                    Ok(HandshakeResult::Incomplete(ServerHandshake {
+                        state: HandshakeState::SendingResponse(resp),
+                        ..self
+                    }))
+                } else {
+                    let ws = WebSocket::from_raw_socket(self.stream, Role::Server);
+                    Ok(HandshakeResult::Done(ws))
+                }
+            }
+        }
+    }
+}
+
+enum HandshakeState {
+    ReceivingRequest(InputBuffer),
+    SendingResponse(Cursor<Vec<u8>>),
+}
+
 #[cfg(test)]
 mod tests {
 
diff --git a/src/lib.rs b/src/lib.rs
index fbd9281..d6185a1 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -22,6 +22,7 @@ extern crate utf8;
 pub mod error;
 pub mod protocol;
 pub mod client;
+pub mod server;
 pub mod handshake;
 
 mod input_buffer;
diff --git a/src/server.rs b/src/server.rs
new file mode 100644
index 0000000..fca1368
--- /dev/null
+++ b/src/server.rs
@@ -0,0 +1,8 @@
+use std::net::TcpStream;
+
+use handshake::server::ServerHandshake;
+
+/// Accept the given TcpStream as a WebSocket.
+pub fn accept(stream: TcpStream) -> ServerHandshake<TcpStream> {
+    ServerHandshake::new(stream)
+}