Check Content-Length loosely.

Author: cloudwebrtc

lib/src/sanity_check.dart

@@ -104,8 +104,10 @@ bool rfc3261_18_3_request() {
   int len = Utils.str_utf8_length(message.body);
   dynamic contentLength = message.getHeader('content-length');
 
-  if (contentLength is String) {
+  if (contentLength != null && contentLength is String) {
     contentLength = int.tryParse(contentLength) ?? 0;
+  } else {
+    contentLength = 0;
   }
 
   if (len < contentLength) {
@@ -192,8 +194,10 @@ bool rfc3261_18_3_response() {
   // ignore: always_specify_types
   var contentLength = message.getHeader('content-length');
 
-  if (contentLength is String) {
+  if (contentLength != null && contentLength is String) {
     contentLength = int.tryParse(contentLength) ?? 0;
+  } else {
+    contentLength = 0;
   }
 
   if (len < contentLength) {

lib/src/transports/websocket_web_impl.dart

@@ -23,25 +23,25 @@ class WebSocketImpl {
     try {
       _socket = WebSocket(_url, 'sip');
       _socket.onOpen.listen((Event e) {
-        this?.onOpen();
+        onOpen?.call();
       });
 
       _socket.onMessage.listen((MessageEvent e) async {
         if (e.data is Blob) {
           dynamic arrayBuffer = await JSUtils.promiseToFuture(
               JSUtils.callMethod(e.data, 'arrayBuffer', <Object>[]));
           String message = String.fromCharCodes(arrayBuffer.asUint8List());
-          this?.onMessage(message);
+          onMessage?.call(message);
         } else {
-          this?.onMessage(e.data);
+          onMessage?.call(e.data);
         }
       });
 
       _socket.onClose.listen((CloseEvent e) {
-        this?.onClose(e.code, e.reason);
+        onClose?.call(e.code, e.reason);
       });
     } catch (e) {
-      this?.onClose(e.code, e.reason);
+      onClose?.call(e.code, e.reason);
     }
   }