Make event-handlers edge-triggered and move socket-state to Dart.

sdk/lib/io/websocket_impl.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 const String _webSocketGUID = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
 
 // Matches _WebSocketOpcode.
 class _WebSocketMessageType {
@@ skipping 763 matching lines @@
   int _readyState = WebSocket.CONNECTING;
   bool _writeClosed = false;
   int _closeCode;
   String _closeReason;
   Duration _pingInterval;
   Timer _pingTimer;
   _WebSocketConsumer _consumer;
 
   int _outCloseCode;
   String _outCloseReason;
+  Timer _closeTimer;
 
   static final HttpClient _httpClient = new HttpClient();
 
   static Future<WebSocket> connect(String url, List<String> protocols) {
     Uri uri = Uri.parse(url);
     if (uri.scheme != "ws" && uri.scheme != "wss") {
       throw new WebSocketException("Unsupported URL scheme '${uri.scheme}'");
     }
     if (uri.userInfo != "") {
       throw new WebSocketException("Unsupported user info '${uri.userInfo}'");
@@ skipping 78 matching lines @@
           if (data is _WebSocketPing) {
             if (!_writeClosed) _consumer.add(new _WebSocketPong(data.payload));
           } else if (data is _WebSocketPong) {
             // Simply set pingInterval, as it'll cancel any timers.
             pingInterval = _pingInterval;
           } else {
             _controller.add(data);
           }
         },
         onError: (error) {
+          if (_closeTimer != null) _closeTimer.cancel();
           if (error is FormatException) {
             _close(WebSocketStatus.INVALID_FRAME_PAYLOAD_DATA);
           } else {
             _close(WebSocketStatus.PROTOCOL_ERROR);
           }
           _controller.close();
         },
         onDone: () {
+          if (_closeTimer != null) _closeTimer.cancel();
           if (_readyState == WebSocket.OPEN) {
             _readyState = WebSocket.CLOSING;
             if (!_isReservedStatusCode(transformer.closeCode)) {
               _close(transformer.closeCode);
             } else {
               _close();
             }
             _readyState = WebSocket.CLOSED;
           }
           _closeCode = transformer.closeCode;
@@ skipping 50 matching lines @@
   Future get done => _sink.done;
 
   Future close([int code, String reason]) {
     if (_isReservedStatusCode(code)) {
       throw new WebSocketException("Reserved status code $code");
     }
     if (_outCloseCode == null) {
       _outCloseCode = code;
       _outCloseReason = reason;
     }
+    if (_closeTimer == null && !_controller.isClosed) {
+      // When closing the web-socket, we no longer accept data.
+      _closeTimer = new Timer(const Duration(seconds: 5), () {
+        _subscription.cancel();
+        _controller.close();
+      });
+    }
     return _sink.close();
   }
 
   void _close([int code, String reason]) {
     if (_writeClosed) return;
     if (_outCloseCode == null) {
       _outCloseCode = code;
       _outCloseReason = reason;
     }
     _writeClosed = true;
     _consumer.closeSocket();
   }
 
   static bool _isReservedStatusCode(int code) {
     return code != null &&
            (code < WebSocketStatus.NORMAL_CLOSURE ||
             code == WebSocketStatus.RESERVED_1004 ||
             code == WebSocketStatus.NO_STATUS_RECEIVED ||
             code == WebSocketStatus.ABNORMAL_CLOSURE ||
             (code > WebSocketStatus.INTERNAL_SERVER_ERROR &&
              code < WebSocketStatus.RESERVED_1015) ||
             (code >= WebSocketStatus.RESERVED_1015 &&
              code < 3000));
   }
 }