[PATCH 1/4] gstreamer: Fix reconfiguration condition check

[Jaslo Ziska]

gst_pad_peer_query_accept_caps() might only check if the caps are
acceptable with the peer element, but not recursively with all
downstream elements. If the reconfigure flag was set because the
pipeline downstream changed, gst_pad_peer_query_accept_caps() might still
return true, even though downstream can't handle the current caps, which
causes a not-negotiated error.

This commit fixes this issue by emitting a query event which
recursively checks with all downstream elements. Because at this point
we are only interested in whether the current caps are still acceptable,
use the currently used caps as a filter and then check if the query
returned empty caps.

Signed-off-by: Jaslo Ziska <jaslo at ziska.de>
---
 src/gstreamer/gstlibcamerasrc.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/gstreamer/gstlibcamerasrc.cpp b/src/gstreamer/gstlibcamerasrc.cpp
index 5e9e843d..12bf8de0 100644
--- a/src/gstreamer/gstlibcamerasrc.cpp
+++ b/src/gstreamer/gstlibcamerasrc.cpp
@@ -548,7 +548,7 @@ gst_libcamera_src_task_run(gpointer user_data)
 		if (gst_pad_check_reconfigure(srcpad)) {
 			/* Check if the caps even need changing. */
 			g_autoptr(GstCaps) caps = gst_pad_get_current_caps(srcpad);
-			if (!gst_pad_peer_query_accept_caps(srcpad, caps)) {
+			if (gst_caps_is_empty(gst_pad_peer_query_caps(srcpad, caps))) {
 				reconfigure = true;
 				break;
 			}
-- 
2.49.0