diff --git a/lib/nghttp2_session.c b/lib/nghttp2_session.c
index adce16af..da5a6e55 100644
--- a/lib/nghttp2_session.c
+++ b/lib/nghttp2_session.c
@@ -2483,196 +2483,11 @@ static int session_after_frame_sent1(nghttp2_session *session) {
   nghttp2_outbound_item *item = aob->item;
   nghttp2_bufs *framebufs = &aob->framebufs;
   nghttp2_frame *frame;
+  nghttp2_stream *stream;
 
   frame = &item->frame;
 
-  if (frame->hd.type != NGHTTP2_DATA) {
-
-    if (frame->hd.type == NGHTTP2_HEADERS ||
-        frame->hd.type == NGHTTP2_PUSH_PROMISE) {
-
-      if (nghttp2_bufs_next_present(framebufs)) {
-        DEBUGF(fprintf(stderr, "send: CONTINUATION exists, just return\n"));
-        return 0;
-      }
-    }
-    rv = session_call_on_frame_send(session, frame);
-    if (nghttp2_is_fatal(rv)) {
-      return rv;
-    }
-    switch (frame->hd.type) {
-    case NGHTTP2_HEADERS: {
-      nghttp2_headers_aux_data *aux_data;
-      nghttp2_stream *stream;
-
-      stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
-      if (!stream) {
-        break;
-      }
-
-      switch (frame->headers.cat) {
-      case NGHTTP2_HCAT_REQUEST: {
-        stream->state = NGHTTP2_STREAM_OPENING;
-        if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
-          nghttp2_stream_shutdown(stream, NGHTTP2_SHUT_WR);
-        }
-        rv = nghttp2_session_close_stream_if_shut_rdwr(session, stream);
-        if (nghttp2_is_fatal(rv)) {
-          return rv;
-        }
-        /* We assume aux_data is a pointer to nghttp2_headers_aux_data */
-        aux_data = &item->aux_data.headers;
-        if (aux_data->data_prd.read_callback) {
-          /* nghttp2_submit_data() makes a copy of aux_data->data_prd */
-          rv = nghttp2_submit_data(session, NGHTTP2_FLAG_END_STREAM,
-                                   frame->hd.stream_id, &aux_data->data_prd);
-          if (nghttp2_is_fatal(rv)) {
-            return rv;
-          }
-          /* TODO nghttp2_submit_data() may fail if stream has already
-             DATA frame item.  We might have to handle it here. */
-        }
-        break;
-      }
-      case NGHTTP2_HCAT_PUSH_RESPONSE:
-        stream->flags = (uint8_t)(stream->flags & ~NGHTTP2_STREAM_FLAG_PUSH);
-        ++session->num_outgoing_streams;
-      /* Fall through */
-      case NGHTTP2_HCAT_RESPONSE:
-        stream->state = NGHTTP2_STREAM_OPENED;
-      /* Fall through */
-      case NGHTTP2_HCAT_HEADERS:
-        if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
-          nghttp2_stream_shutdown(stream, NGHTTP2_SHUT_WR);
-        }
-        rv = nghttp2_session_close_stream_if_shut_rdwr(session, stream);
-        if (nghttp2_is_fatal(rv)) {
-          return rv;
-        }
-        /* We assume aux_data is a pointer to nghttp2_headers_aux_data */
-        aux_data = &item->aux_data.headers;
-        if (aux_data->data_prd.read_callback) {
-          rv = nghttp2_submit_data(session, NGHTTP2_FLAG_END_STREAM,
-                                   frame->hd.stream_id, &aux_data->data_prd);
-          if (nghttp2_is_fatal(rv)) {
-            return rv;
-          }
-          /* TODO nghttp2_submit_data() may fail if stream has already
-             DATA frame item.  We might have to handle it here. */
-        }
-        break;
-      }
-      break;
-    }
-    case NGHTTP2_PRIORITY: {
-      nghttp2_stream *stream;
-
-      if (session->server) {
-        break;
-      }
-
-      stream = nghttp2_session_get_stream_raw(session, frame->hd.stream_id);
-
-      if (!stream) {
-        if (!session_detect_idle_stream(session, frame->hd.stream_id)) {
-          break;
-        }
-
-        stream = nghttp2_session_open_stream(
-            session, frame->hd.stream_id, NGHTTP2_FLAG_NONE,
-            &frame->priority.pri_spec, NGHTTP2_STREAM_IDLE, NULL);
-        if (!stream) {
-          return NGHTTP2_ERR_NOMEM;
-        }
-      } else {
-        rv = nghttp2_session_reprioritize_stream(session, stream,
-                                                 &frame->priority.pri_spec);
-        if (nghttp2_is_fatal(rv)) {
-          return rv;
-        }
-      }
-
-      rv = nghttp2_session_adjust_idle_stream(session);
-
-      if (nghttp2_is_fatal(rv)) {
-        return rv;
-      }
-
-      break;
-    }
-    case NGHTTP2_RST_STREAM:
-      rv = nghttp2_session_close_stream(session, frame->hd.stream_id,
-                                        frame->rst_stream.error_code);
-      if (nghttp2_is_fatal(rv)) {
-        return rv;
-      }
-      break;
-    case NGHTTP2_GOAWAY: {
-      nghttp2_goaway_aux_data *aux_data;
-
-      aux_data = &item->aux_data.goaway;
-
-      if ((aux_data->flags & NGHTTP2_GOAWAY_AUX_SHUTDOWN_NOTICE) == 0) {
-
-        if (aux_data->flags & NGHTTP2_GOAWAY_AUX_TERM_ON_SEND) {
-          session->goaway_flags |= NGHTTP2_GOAWAY_TERM_SENT;
-        }
-
-        session->goaway_flags |= NGHTTP2_GOAWAY_SENT;
-
-        rv = session_close_stream_on_goaway(session,
-                                            frame->goaway.last_stream_id, 1);
-
-        if (nghttp2_is_fatal(rv)) {
-          return rv;
-        }
-      }
-
-      break;
-    }
-    case NGHTTP2_WINDOW_UPDATE:
-      if (frame->hd.stream_id == 0) {
-        session->window_update_queued = 0;
-        if (session->opt_flags & NGHTTP2_OPTMASK_NO_AUTO_WINDOW_UPDATE) {
-          rv = session_update_connection_consumed_size(session, 0);
-        } else {
-          rv = session_update_recv_connection_window_size(session, 0);
-        }
-      } else {
-        nghttp2_stream *stream;
-
-        stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
-        if (!stream) {
-          break;
-        }
-
-        stream->window_update_queued = 0;
-
-        /* We don't have to send WINDOW_UPDATE if END_STREAM from peer
-           is seen. */
-        if (stream->shut_flags & NGHTTP2_SHUT_RD) {
-          break;
-        }
-
-        if (session->opt_flags & NGHTTP2_OPTMASK_NO_AUTO_WINDOW_UPDATE) {
-          rv = session_update_stream_consumed_size(session, stream, 0);
-        } else {
-          rv = session_update_recv_stream_window_size(session, stream, 0, 1);
-        }
-      }
-
-      if (nghttp2_is_fatal(rv)) {
-        return rv;
-      }
-
-      break;
-    default:
-      break;
-    }
-
-    return 0;
-  } else {
-    nghttp2_stream *stream;
+  if (frame->hd.type == NGHTTP2_DATA) {
     nghttp2_data_aux_data *aux_data;
 
     aux_data = &item->aux_data.data;
@@ -2688,7 +2503,6 @@ static int session_after_frame_sent1(nghttp2_session *session) {
 
     if (stream && aux_data->eof) {
       rv = nghttp2_stream_detach_item(stream);
-
       if (nghttp2_is_fatal(rv)) {
         return rv;
       }
@@ -2698,7 +2512,6 @@ static int session_after_frame_sent1(nghttp2_session *session) {
          nghttp2_submit_data() in the callback. */
       if (session->callbacks.on_frame_send_callback) {
         rv = session_call_on_frame_send(session, frame);
-
         if (nghttp2_is_fatal(rv)) {
           return rv;
         }
@@ -2726,6 +2539,149 @@ static int session_after_frame_sent1(nghttp2_session *session) {
 
     if (session->callbacks.on_frame_send_callback) {
       rv = session_call_on_frame_send(session, frame);
+      if (nghttp2_is_fatal(rv)) {
+        return rv;
+      }
+    }
+
+    return 0;
+  }
+
+  /* non-DATA frame */
+
+  if (frame->hd.type == NGHTTP2_HEADERS ||
+      frame->hd.type == NGHTTP2_PUSH_PROMISE) {
+    if (nghttp2_bufs_next_present(framebufs)) {
+      DEBUGF(fprintf(stderr, "send: CONTINUATION exists, just return\n"));
+      return 0;
+    }
+  }
+  rv = session_call_on_frame_send(session, frame);
+  if (nghttp2_is_fatal(rv)) {
+    return rv;
+  }
+  switch (frame->hd.type) {
+  case NGHTTP2_HEADERS: {
+    nghttp2_headers_aux_data *aux_data;
+
+    stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
+    if (!stream) {
+      return 0;
+    }
+
+    switch (frame->headers.cat) {
+    case NGHTTP2_HCAT_REQUEST: {
+      stream->state = NGHTTP2_STREAM_OPENING;
+      if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
+        nghttp2_stream_shutdown(stream, NGHTTP2_SHUT_WR);
+      }
+      rv = nghttp2_session_close_stream_if_shut_rdwr(session, stream);
+      if (nghttp2_is_fatal(rv)) {
+        return rv;
+      }
+      /* We assume aux_data is a pointer to nghttp2_headers_aux_data */
+      aux_data = &item->aux_data.headers;
+      if (aux_data->data_prd.read_callback) {
+        /* nghttp2_submit_data() makes a copy of aux_data->data_prd */
+        rv = nghttp2_submit_data(session, NGHTTP2_FLAG_END_STREAM,
+                                 frame->hd.stream_id, &aux_data->data_prd);
+        if (nghttp2_is_fatal(rv)) {
+          return rv;
+        }
+        /* TODO nghttp2_submit_data() may fail if stream has already
+           DATA frame item.  We might have to handle it here. */
+      }
+      return 0;
+    }
+    case NGHTTP2_HCAT_PUSH_RESPONSE:
+      stream->flags = (uint8_t)(stream->flags & ~NGHTTP2_STREAM_FLAG_PUSH);
+      ++session->num_outgoing_streams;
+    /* Fall through */
+    case NGHTTP2_HCAT_RESPONSE:
+      stream->state = NGHTTP2_STREAM_OPENED;
+    /* Fall through */
+    case NGHTTP2_HCAT_HEADERS:
+      if (frame->hd.flags & NGHTTP2_FLAG_END_STREAM) {
+        nghttp2_stream_shutdown(stream, NGHTTP2_SHUT_WR);
+      }
+      rv = nghttp2_session_close_stream_if_shut_rdwr(session, stream);
+      if (nghttp2_is_fatal(rv)) {
+        return rv;
+      }
+      /* We assume aux_data is a pointer to nghttp2_headers_aux_data */
+      aux_data = &item->aux_data.headers;
+      if (aux_data->data_prd.read_callback) {
+        rv = nghttp2_submit_data(session, NGHTTP2_FLAG_END_STREAM,
+                                 frame->hd.stream_id, &aux_data->data_prd);
+        if (nghttp2_is_fatal(rv)) {
+          return rv;
+        }
+        /* TODO nghttp2_submit_data() may fail if stream has already
+           DATA frame item.  We might have to handle it here. */
+      }
+      return 0;
+    default:
+      /* Unreachable */
+      assert(0);
+      return 0;
+    }
+  }
+  case NGHTTP2_PRIORITY:
+    if (session->server) {
+      return 0;
+      ;
+    }
+
+    stream = nghttp2_session_get_stream_raw(session, frame->hd.stream_id);
+
+    if (!stream) {
+      if (!session_detect_idle_stream(session, frame->hd.stream_id)) {
+        return 0;
+      }
+
+      stream = nghttp2_session_open_stream(
+          session, frame->hd.stream_id, NGHTTP2_FLAG_NONE,
+          &frame->priority.pri_spec, NGHTTP2_STREAM_IDLE, NULL);
+      if (!stream) {
+        return NGHTTP2_ERR_NOMEM;
+      }
+    } else {
+      rv = nghttp2_session_reprioritize_stream(session, stream,
+                                               &frame->priority.pri_spec);
+      if (nghttp2_is_fatal(rv)) {
+        return rv;
+      }
+    }
+
+    rv = nghttp2_session_adjust_idle_stream(session);
+
+    if (nghttp2_is_fatal(rv)) {
+      return rv;
+    }
+
+    return 0;
+  case NGHTTP2_RST_STREAM:
+    rv = nghttp2_session_close_stream(session, frame->hd.stream_id,
+                                      frame->rst_stream.error_code);
+    if (nghttp2_is_fatal(rv)) {
+      return rv;
+    }
+    return 0;
+  case NGHTTP2_GOAWAY: {
+    nghttp2_goaway_aux_data *aux_data;
+
+    aux_data = &item->aux_data.goaway;
+
+    if ((aux_data->flags & NGHTTP2_GOAWAY_AUX_SHUTDOWN_NOTICE) == 0) {
+
+      if (aux_data->flags & NGHTTP2_GOAWAY_AUX_TERM_ON_SEND) {
+        session->goaway_flags |= NGHTTP2_GOAWAY_TERM_SENT;
+      }
+
+      session->goaway_flags |= NGHTTP2_GOAWAY_SENT;
+
+      rv = session_close_stream_on_goaway(session, frame->goaway.last_stream_id,
+                                          1);
 
       if (nghttp2_is_fatal(rv)) {
         return rv;
@@ -2734,9 +2690,49 @@ static int session_after_frame_sent1(nghttp2_session *session) {
 
     return 0;
   }
-  /* Unreachable */
-  assert(0);
-  return 0;
+  case NGHTTP2_WINDOW_UPDATE:
+    if (frame->hd.stream_id == 0) {
+      session->window_update_queued = 0;
+      if (session->opt_flags & NGHTTP2_OPTMASK_NO_AUTO_WINDOW_UPDATE) {
+        rv = session_update_connection_consumed_size(session, 0);
+      } else {
+        rv = session_update_recv_connection_window_size(session, 0);
+      }
+
+      if (nghttp2_is_fatal(rv)) {
+        return rv;
+      }
+
+      return 0;
+    }
+
+    stream = nghttp2_session_get_stream(session, frame->hd.stream_id);
+    if (!stream) {
+      return 0;
+    }
+
+    stream->window_update_queued = 0;
+
+    /* We don't have to send WINDOW_UPDATE if END_STREAM from peer
+       is seen. */
+    if (stream->shut_flags & NGHTTP2_SHUT_RD) {
+      return 0;
+    }
+
+    if (session->opt_flags & NGHTTP2_OPTMASK_NO_AUTO_WINDOW_UPDATE) {
+      rv = session_update_stream_consumed_size(session, stream, 0);
+    } else {
+      rv = session_update_recv_stream_window_size(session, stream, 0, 1);
+    }
+
+    if (nghttp2_is_fatal(rv)) {
+      return rv;
+    }
+
+    return 0;
+  default:
+    return 0;
+  }
 }
 
 /*