Merge pull request #1444 from nghttp2/fix-recv-window-flow-control-issue

Fix receiving stream data stall

lib/nghttp2_session.c

@@ -2494,14 +2494,6 @@ static int session_update_stream_consumed_size(nghttp2_session *session,
 static int session_update_connection_consumed_size(nghttp2_session *session,
                                                    size_t delta_size);
 
-static int session_update_recv_connection_window_size(nghttp2_session *session,
-                                                      size_t delta_size);
-
-static int session_update_recv_stream_window_size(nghttp2_session *session,
-                                                  nghttp2_stream *stream,
-                                                  size_t delta_size,
-                                                  int send_window_update);
-
 /*
  * Called after a frame is sent.  This function runs
  * on_frame_send_callback and handles stream closure upon END_STREAM
@@ -2735,7 +2727,7 @@ static int session_after_frame_sent1(nghttp2_session *session) {
       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);
+        rv = nghttp2_session_update_recv_connection_window_size(session, 0);
       }
 
       if (nghttp2_is_fatal(rv)) {
@@ -2761,7 +2753,8 @@ static int session_after_frame_sent1(nghttp2_session *session) {
     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);
+      rv =
+          nghttp2_session_update_recv_stream_window_size(session, stream, 0, 1);
     }
 
     if (nghttp2_is_fatal(rv)) {
@@ -5019,22 +5012,10 @@ static int adjust_recv_window_size(int32_t *recv_window_size_ptr, size_t delta,
   return 0;
 }
 
-/*
+int nghttp2_session_update_recv_stream_window_size(nghttp2_session *session,
- * Accumulates received bytes |delta_size| for stream-level flow
+                                                   nghttp2_stream *stream,
- * control and decides whether to send WINDOW_UPDATE to that stream.
+                                                   size_t delta_size,
- * If NGHTTP2_OPT_NO_AUTO_WINDOW_UPDATE is set, WINDOW_UPDATE will not
+                                                   int send_window_update) {
- * be sent.
- *
- * This function returns 0 if it succeeds, or one of the following
- * negative error codes:
- *
- * NGHTTP2_ERR_NOMEM
- *     Out of memory.
- */
-static int session_update_recv_stream_window_size(nghttp2_session *session,
-                                                  nghttp2_stream *stream,
-                                                  size_t delta_size,
-                                                  int send_window_update) {
   int rv;
   rv = adjust_recv_window_size(&stream->recv_window_size, delta_size,
                                stream->local_window_size);
@@ -5063,20 +5044,8 @@ static int session_update_recv_stream_window_size(nghttp2_session *session,
   return 0;
 }
 
-/*
+int nghttp2_session_update_recv_connection_window_size(nghttp2_session *session,
- * Accumulates received bytes |delta_size| for connection-level flow
+                                                       size_t delta_size) {
- * control and decides whether to send WINDOW_UPDATE to the
- * connection.  If NGHTTP2_OPT_NO_AUTO_WINDOW_UPDATE is set,
- * WINDOW_UPDATE will not be sent.
- *
- * This function returns 0 if it succeeds, or one of the following
- * negative error codes:
- *
- * NGHTTP2_ERR_NOMEM
- *     Out of memory.
- */
-static int session_update_recv_connection_window_size(nghttp2_session *session,
-                                                      size_t delta_size) {
   int rv;
   rv = adjust_recv_window_size(&session->recv_window_size, delta_size,
                                session->local_window_size);
@@ -6454,7 +6423,7 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session, const uint8_t *in,
       }
 
       /* Pad Length field is subject to flow control */
-      rv = session_update_recv_connection_window_size(session, readlen);
+      rv = nghttp2_session_update_recv_connection_window_size(session, readlen);
       if (nghttp2_is_fatal(rv)) {
         return rv;
       }
@@ -6477,7 +6446,7 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session, const uint8_t *in,
 
       stream = nghttp2_session_get_stream(session, iframe->frame.hd.stream_id);
       if (stream) {
-        rv = session_update_recv_stream_window_size(
+        rv = nghttp2_session_update_recv_stream_window_size(
             session, stream, readlen,
             iframe->payloadleft ||
                 (iframe->frame.hd.flags & NGHTTP2_FLAG_END_STREAM) == 0);
@@ -6524,7 +6493,8 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session, const uint8_t *in,
       if (readlen > 0) {
         ssize_t data_readlen;
 
-        rv = session_update_recv_connection_window_size(session, readlen);
+        rv = nghttp2_session_update_recv_connection_window_size(session,
+                                                                readlen);
         if (nghttp2_is_fatal(rv)) {
           return rv;
         }
@@ -6533,7 +6503,7 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session, const uint8_t *in,
           return (ssize_t)inlen;
         }
 
-        rv = session_update_recv_stream_window_size(
+        rv = nghttp2_session_update_recv_stream_window_size(
             session, stream, readlen,
             iframe->payloadleft ||
                 (iframe->frame.hd.flags & NGHTTP2_FLAG_END_STREAM) == 0);
@@ -6634,7 +6604,8 @@ ssize_t nghttp2_session_mem_recv(nghttp2_session *session, const uint8_t *in,
       if (readlen > 0) {
         /* Update connection-level flow control window for ignored
            DATA frame too */
-        rv = session_update_recv_connection_window_size(session, readlen);
+        rv = nghttp2_session_update_recv_connection_window_size(session,
+                                                                readlen);
         if (nghttp2_is_fatal(rv)) {
           return rv;
         }

lib/nghttp2_session.h

@@ -898,4 +898,36 @@ int nghttp2_session_terminate_session_with_reason(nghttp2_session *session,
                                                   uint32_t error_code,
                                                   const char *reason);
 
+/*
+ * Accumulates received bytes |delta_size| for connection-level flow
+ * control and decides whether to send WINDOW_UPDATE to the
+ * connection.  If NGHTTP2_OPT_NO_AUTO_WINDOW_UPDATE is set,
+ * WINDOW_UPDATE will not be sent.
+ *
+ * This function returns 0 if it succeeds, or one of the following
+ * negative error codes:
+ *
+ * NGHTTP2_ERR_NOMEM
+ *     Out of memory.
+ */
+int nghttp2_session_update_recv_connection_window_size(nghttp2_session *session,
+                                                       size_t delta_size);
+
+/*
+ * Accumulates received bytes |delta_size| for stream-level flow
+ * control and decides whether to send WINDOW_UPDATE to that stream.
+ * If NGHTTP2_OPT_NO_AUTO_WINDOW_UPDATE is set, WINDOW_UPDATE will not
+ * be sent.
+ *
+ * This function returns 0 if it succeeds, or one of the following
+ * negative error codes:
+ *
+ * NGHTTP2_ERR_NOMEM
+ *     Out of memory.
+ */
+int nghttp2_session_update_recv_stream_window_size(nghttp2_session *session,
+                                                   nghttp2_stream *stream,
+                                                   size_t delta_size,
+                                                   int send_window_update);
+
 #endif /* NGHTTP2_SESSION_H */

lib/nghttp2_submit.c

@@ -450,6 +450,13 @@ int nghttp2_session_set_local_window_size(nghttp2_session *session,
     if (rv != 0) {
       return rv;
     }
+
+    if (window_size_increment > 0) {
+      return nghttp2_session_add_window_update(session, 0, stream_id,
+                                               window_size_increment);
+    }
+
+    return nghttp2_session_update_recv_connection_window_size(session, 0);
   } else {
     stream = nghttp2_session_get_stream(session, stream_id);
 
@@ -476,11 +483,14 @@ int nghttp2_session_set_local_window_size(nghttp2_session *session,
     if (rv != 0) {
       return rv;
     }
-  }
 
-  if (window_size_increment > 0) {
+    if (window_size_increment > 0) {
-    return nghttp2_session_add_window_update(session, 0, stream_id,
+      return nghttp2_session_add_window_update(session, 0, stream_id,
-                                             window_size_increment);
+                                               window_size_increment);
+    }
+
+    return nghttp2_session_update_recv_stream_window_size(session, stream, 0,
+                                                          1);
   }
 
   return 0;

tests/nghttp2_session_test.c

@@ -10468,6 +10468,62 @@ void test_nghttp2_session_set_local_window_size(void) {
   CU_ASSERT(0 == nghttp2_session_send(session));
 
   nghttp2_session_del(session);
+
+  /* Make sure that nghttp2_session_set_local_window_size submits
+     WINDOW_UPDATE if necessary to increase stream-level window. */
+  nghttp2_session_client_new(&session, &callbacks, NULL);
+  stream = open_sent_stream(session, 1);
+  stream->recv_window_size = NGHTTP2_INITIAL_WINDOW_SIZE;
+
+  CU_ASSERT(0 == nghttp2_session_set_local_window_size(
+                     session, NGHTTP2_FLAG_NONE, 1, 0));
+  CU_ASSERT(0 == stream->recv_window_size);
+  CU_ASSERT(0 == nghttp2_session_get_stream_local_window_size(session, 1));
+  /* This should submit WINDOW_UPDATE frame because stream-level
+     receiving window is now full. */
+  CU_ASSERT(0 ==
+            nghttp2_session_set_local_window_size(session, NGHTTP2_FLAG_NONE, 1,
+                                                  NGHTTP2_INITIAL_WINDOW_SIZE));
+  CU_ASSERT(0 == stream->recv_window_size);
+  CU_ASSERT(NGHTTP2_INITIAL_WINDOW_SIZE ==
+            nghttp2_session_get_stream_local_window_size(session, 1));
+
+  item = nghttp2_session_get_next_ob_item(session);
+
+  CU_ASSERT(NGHTTP2_WINDOW_UPDATE == item->frame.hd.type);
+  CU_ASSERT(1 == item->frame.hd.stream_id);
+  CU_ASSERT(NGHTTP2_INITIAL_WINDOW_SIZE ==
+            item->frame.window_update.window_size_increment);
+
+  nghttp2_session_del(session);
+
+  /* Make sure that nghttp2_session_set_local_window_size submits
+     WINDOW_UPDATE if necessary to increase connection-level
+     window. */
+  nghttp2_session_client_new(&session, &callbacks, NULL);
+  session->recv_window_size = NGHTTP2_INITIAL_WINDOW_SIZE;
+
+  CU_ASSERT(0 == nghttp2_session_set_local_window_size(
+                     session, NGHTTP2_FLAG_NONE, 0, 0));
+  CU_ASSERT(0 == session->recv_window_size);
+  CU_ASSERT(0 == nghttp2_session_get_local_window_size(session));
+  /* This should submit WINDOW_UPDATE frame because connection-level
+     receiving window is now full. */
+  CU_ASSERT(0 ==
+            nghttp2_session_set_local_window_size(session, NGHTTP2_FLAG_NONE, 0,
+                                                  NGHTTP2_INITIAL_WINDOW_SIZE));
+  CU_ASSERT(0 == session->recv_window_size);
+  CU_ASSERT(NGHTTP2_INITIAL_WINDOW_SIZE ==
+            nghttp2_session_get_local_window_size(session));
+
+  item = nghttp2_session_get_next_ob_item(session);
+
+  CU_ASSERT(NGHTTP2_WINDOW_UPDATE == item->frame.hd.type);
+  CU_ASSERT(0 == item->frame.hd.stream_id);
+  CU_ASSERT(NGHTTP2_INITIAL_WINDOW_SIZE ==
+            item->frame.window_update.window_size_increment);
+
+  nghttp2_session_del(session);
 }
 
 void test_nghttp2_session_cancel_from_before_frame_send(void) {