Add the possibility to pass extra request headers.

Closes: #5

Suggestions for a more convenient API are welcome.

Signed-off-by: Alexey Galakhov <agalakhov@snapview.de>

src/client.rs

@@ -119,6 +119,6 @@ pub fn url_mode(url: &Url) -> Result<Mode> {
 pub fn client<Stream: Read + Write>(url: Url, stream: Stream)
     -> StdResult<WebSocket<Stream>, HandshakeError<Stream, ClientHandshake>>
 {
-    let request = Request { url: url };
+    let request = Request { url: url, extra_headers: None };
     ClientHandshake::start(stream, request).handshake()
 }

src/handshake/client.rs

@@ -13,12 +13,12 @@ use super::{MidHandshake, HandshakeRole, ProcessingResult, convert_key};
 use super::machine::{HandshakeMachine, StageResult, TryParse};
 
 /// Client request.
-pub struct Request {
+pub struct Request<'t> {
     pub url: Url,
-    // TODO extra headers
+    pub extra_headers: Option<&'t [(&'t str, &'t str)]>,
 }
 
-impl Request {
+impl<'t> Request<'t> {
     /// The GET part of the request.
     fn get_path(&self) -> String {
         if let Some(query) = self.url.query() {
@@ -56,9 +56,14 @@ impl ClientHandshake {
                 Connection: upgrade\r\n\
                 Upgrade: websocket\r\n\
                 Sec-WebSocket-Version: 13\r\n\
-                Sec-WebSocket-Key: {key}\r\n\
-                \r\n", host = request.get_host(), path = request.get_path(), key = key)
-                .unwrap();
+                Sec-WebSocket-Key: {key}\r\n",
+                host = request.get_host(), path = request.get_path(), key = key).unwrap();
+            if let Some(eh) = request.extra_headers {
+                for &(k, v) in eh {
+                    write!(req, "{}: {}\r\n", k, v).unwrap();
+                }
+            }
+            write!(req, "\r\n").unwrap();
             HandshakeMachine::start_write(stream, req)
         };