do not add error response if current response is in process

src/lib.rs

@@ -60,7 +60,7 @@ pub use context::HttpContext;
 pub use staticfiles::StaticFiles;
 
 // re-exports
-pub use http::{Method, StatusCode};
+pub use http::{Method, StatusCode, Version};
 pub use cookie::{Cookie, CookieBuilder};
 pub use cookie::{ParseError as CookieParseError};
 pub use http_range::{HttpRange, HttpRangeParseError};

src/server.rs

@@ -324,6 +324,7 @@ impl<T, A, H> Future for HttpChannel<T, A, H>
                         // tasks need to be completed
                         self.error = true;
 
+                        if self.items.is_empty() {
                             if let ReaderError::Error(err) = err {
                                 self.items.push_back(
                                     Entry {task: Task::reply(err),
@@ -333,6 +334,7 @@ impl<T, A, H> Future for HttpChannel<T, A, H>
                                            finished: false});
                             }
                         }
+                    }
                     Ok(Async::NotReady) => {
                         // start keep-alive timer, this is also slow request timeout
                         if self.items.is_empty() && self.inactive.is_empty() {

src/task.rs

@@ -412,7 +412,6 @@ impl Task {
                 fut.borrow_mut().set()
             }
             self.drain.clear();
-            // return self.poll_io(io, req);
         }
 
         // response is completed