[Modify] Polish it

websocket-sharp/Ext.cs

@@ -712,14 +712,24 @@ namespace WebSocketSharp
     {
       using (var dest = new MemoryStream ()) {
         var buff = new byte[bufferLength];
+        var retry = 0;
         var nread = 0;
+
         while (length > 0) {
           if (length < bufferLength)
             bufferLength = (int) length;
 
           nread = stream.Read (buff, 0, bufferLength);
-          if (nread == 0)
+          if (nread <= 0) {
+            if (retry < _retry) {
+              retry++;
+              continue;
+            }
+
             break;
+          }
+
+          retry = 0;
 
           dest.Write (buff, 0, nread);
           length -= nread;