From 8a04a38631479578520eef18363dd1161e3dcb2a Mon Sep 17 00:00:00 2001
From: Seungha Yang <seungha@centricular.com>
Date: Thu, 9 Nov 2023 01:45:51 +0900
Subject: [PATCH] fallbacksrc: Fix timeout scheduling

Other thread can schedule the timeout (e.g., unblock signal
or active pad change) while state lock is released

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1384>
---
 utils/fallbackswitch/src/fallbacksrc/imp.rs | 27 ++++++++++++---------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/utils/fallbackswitch/src/fallbacksrc/imp.rs b/utils/fallbackswitch/src/fallbacksrc/imp.rs
index 9b4a7c17..f1e51e13 100644
--- a/utils/fallbackswitch/src/fallbacksrc/imp.rs
+++ b/utils/fallbackswitch/src/fallbacksrc/imp.rs
@@ -3206,20 +3206,23 @@ impl FallbackSrc {
                         } else {
                             let mut state_guard = imp.state.lock();
                             let state = state_guard.as_mut().expect("no state");
-                            if fallback_source {
-                                assert!(state
-                                    .fallback_source
-                                    .as_ref()
-                                    .map(|s| s.restart_timeout.is_none())
-                                    .unwrap_or(true));
+                            let source = if fallback_source {
+                                if let Some(source) = &state.fallback_source {
+                                    source
+                                } else {
+                                    return;
+                                }
                             } else {
-                                assert!(state.source.restart_timeout.is_none());
+                                &state.source
+                            };
+
+                            if source.restart_timeout.is_none() {
+                                imp.schedule_source_restart_timeout(
+                                    state,
+                                    gst::ClockTime::ZERO,
+                                    fallback_source,
+                                );
                             }
-                            imp.schedule_source_restart_timeout(
-                                state,
-                                gst::ClockTime::ZERO,
-                                fallback_source,
-                            );
                         }
                     });
                 })