Http2: Don't skip checking flag for trailing HEADERS frame if PRIORITY

If the trailing frame just had PRIORITY we would early-return, though
this meant we didn't check if the frame had the END_STREAM flag set,
leading some requests to certain servers to hang.

Fixes: QTBUG-111417
Pick-to: 6.5 6.4 6.2
Change-Id: Iac174dc5aeca30d5d19fae35f303983de9841847
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
Reviewed-by: Konrad Kujawa <konrad.kujawa@qt.io>

1 files changed, 19 insertions, 3 deletions

diff --git a/tests/auto/network/access/http2/http2srv.cpp b/tests/auto/network/access/http2/http2srv.cpp
index bf2625876e..91d57a5caa 100644
--- a/tests/auto/network/access/http2/http2srv.cpp
+++ b/tests/auto/network/access/http2/http2srv.cpp
@@ -111,6 +111,11 @@ void Http2Server::setRedirect(const QByteArray &url, int count)
     redirectCount = count;
 }
 
+void Http2Server::setSendTrailingHEADERS(bool enable)
+{
+    sendTrailingHEADERS = enable;
+}
+
 void Http2Server::emulateGOAWAY(int timeout)
 {
     Q_ASSERT(timeout >= 0);
@@ -248,9 +253,20 @@ void Http2Server::sendDATA(quint32 streamID, quint32 windowSize)
         return;
 
     if (last) {
-        writer.start(FrameType::DATA, FrameFlag::END_STREAM, streamID);
-        writer.setPayloadSize(0);
-        writer.write(*socket);
+        if (sendTrailingHEADERS) {
+            writer.start(FrameType::HEADERS,
+                    FrameFlag::PRIORITY | FrameFlag::END_HEADERS | FrameFlag::END_STREAM, streamID);
+            const quint32 maxFrameSize(clientSetting(Settings::MAX_FRAME_SIZE_ID,
+                    Http2::maxPayloadSize));
+            // 5 bytes for PRIORITY data:
+            writer.append(quint32(0)); // streamID 0 (32-bit)
+            writer.append(quint8(0)); // + weight 0 (8-bit)
+            writer.writeHEADERS(*socket, maxFrameSize);
+        } else {
+            writer.start(FrameType::DATA, FrameFlag::END_STREAM, streamID);
+            writer.setPayloadSize(0);
+            writer.write(*socket);
+        }
         suspendedStreams.erase(it);
         activeRequests.erase(streamID);