Cope with screen==NULL in screen_appsink_new_sample()

I saw a crash with this once, in a long sequence of sharing from A to B
and then B to A testing screen sharing startup/teardown.

It looksl like a race condition when we change to the no_appsink_callbacks
but the callback is already in progress, and the cbdata gets set to NULL.

diff --git a/chime/chime-call-screen.c b/chime/chime-call-screen.c
index b038a432b6e5132abf9755b25d56c1df822554cd..939fc243751b412bcc8e086ad95cb25d5f4fef6e 100644 (file)
--- a/chime/chime-call-screen.c
+++ b/chime/chime-call-screen.c
@@ -379,6 +379,9 @@ static GstFlowReturn screen_appsink_new_sample(GstAppSink* self, gpointer data)
        if (!sample)
                return GST_FLOW_OK;
 
+       if (!screen)
+               return GST_FLOW_ERROR;
+
        if (screen->state == CHIME_SCREEN_STATE_SENDING && screen->viewer_present) {
                GstBuffer *buffer = gst_sample_get_buffer(sample);
                gsize len = gst_buffer_get_size(buffer);