Add test to submit DATA frame twice

This commit adds test to submit DATA frame twice and fixes the bug
that 2nd DATA is not sent.

lib/nghttp2_session.c

@@ -2160,12 +2160,21 @@ static int session_after_frame_sent(nghttp2_session *session)
       }
     }
 
+    /* On EOF, we have already detached data if stream is not NULL.
+       If stream is NULL, we cannot detach data.  Please note that
+       application may issue nghttp2_submit_data() in
+       on_frame_send_callback, which attach data to stream.  We don't
+       want to detach it. */
+    if(data_frame->eof) {
+      active_outbound_item_reset(aob);
+
+      return 0;
+    }
+
     /* If session is closed or RST_STREAM was queued, we won't send
        further data. */
-    if(data_frame->eof ||
-       nghttp2_session_predicate_data_send(session,
+    if(nghttp2_session_predicate_data_send(session,
                                            data_frame->hd.stream_id) != 0) {
-
       if(stream) {
         rv = nghttp2_stream_detach_data(stream, &session->ob_pq,
                                         session->last_cycle);

tests/main.c

@@ -144,6 +144,8 @@ int main(int argc, char* argv[])
       !CU_add_test(pSuite, "submit_data", test_nghttp2_submit_data) ||
       !CU_add_test(pSuite, "submit_data_read_length_too_large",
                    test_nghttp2_submit_data_read_length_too_large) ||
+      !CU_add_test(pSuite, "submit_data_twice",
+                   test_nghttp2_submit_data_twice) ||
       !CU_add_test(pSuite, "submit_request_with_data",
                    test_nghttp2_submit_request_with_data) ||
       !CU_add_test(pSuite, "submit_request_without_data",

tests/nghttp2_session_test.c

@@ -3207,6 +3207,72 @@ void test_nghttp2_submit_data_read_length_smallest(void)
   nghttp2_session_del(session);
 }
 
+static ssize_t submit_data_twice_data_source_read_callback
+(nghttp2_session *session, int32_t stream_id,
+ uint8_t *buf, size_t len, uint32_t *data_flags,
+ nghttp2_data_source *source, void *user_data)
+{
+  *data_flags |= NGHTTP2_DATA_FLAG_EOF;
+  return nghttp2_min(len, 16);
+}
+
+static int submit_data_twice_on_frame_send_callback(nghttp2_session *session,
+                                                    const nghttp2_frame *frame,
+                                                    void *user_data)
+{
+  static int called = 0;
+  int rv;
+  nghttp2_data_provider data_prd;
+
+  if(called == 0) {
+    called = 1;
+
+    data_prd.read_callback = submit_data_twice_data_source_read_callback;
+
+    rv = nghttp2_submit_data(session, NGHTTP2_FLAG_END_STREAM,
+                             frame->hd.stream_id, &data_prd);
+    CU_ASSERT(0 == rv);
+  }
+
+  return 0;
+}
+
+void test_nghttp2_submit_data_twice(void)
+{
+  nghttp2_session *session;
+  nghttp2_session_callbacks callbacks;
+  nghttp2_data_provider data_prd;
+  my_user_data ud;
+  accumulator acc;
+
+  memset(&callbacks, 0, sizeof(nghttp2_session_callbacks));
+  callbacks.send_callback = accumulator_send_callback;
+  callbacks.on_frame_send_callback = submit_data_twice_on_frame_send_callback;
+
+  data_prd.read_callback = submit_data_twice_data_source_read_callback;
+
+  acc.length = 0;
+  ud.acc = &acc;
+
+  CU_ASSERT(0 == nghttp2_session_client_new(&session, &callbacks, &ud));
+
+  nghttp2_session_open_stream(session, 1, NGHTTP2_STREAM_FLAG_NONE,
+                              &pri_spec_default, NGHTTP2_STREAM_OPENING,
+                              NULL);
+
+  CU_ASSERT(0 == nghttp2_submit_data(session,
+                                     NGHTTP2_FLAG_NONE, 1, &data_prd));
+
+  CU_ASSERT(0 == nghttp2_session_send(session));
+
+  fprintf(stderr, "acc.length=%zu\n", acc.length);
+
+  /* We should have sent 2 DATA frame with 16 bytes payload each */
+  CU_ASSERT(NGHTTP2_FRAME_HDLEN * 2 + 16 * 2 == acc.length);
+
+  nghttp2_session_del(session);
+}
+
 void test_nghttp2_submit_request_with_data(void)
 {
   nghttp2_session *session;

tests/nghttp2_session_test.h

@@ -64,6 +64,7 @@ void test_nghttp2_session_reprioritize_stream(void);
 void test_nghttp2_submit_data(void);
 void test_nghttp2_submit_data_read_length_too_large(void);
 void test_nghttp2_submit_data_read_length_smallest(void);
+void test_nghttp2_submit_data_twice(void);
 void test_nghttp2_submit_request_with_data(void);
 void test_nghttp2_submit_request_without_data(void);
 void test_nghttp2_submit_response_with_data(void);