[libcamera-devel] [PATCH 04/12] libcamera: thread: Ensure deferred deletion of all objects before stopping

[Laurent Pinchart]

Objects can be scheduled for deletion with Object::deleteLater(), which
queues a deferred deletion to the thread's event loop. As the
deleteLater() function is meant to be called from a different thread,
this may race with thread termination, and deferred deletions queued
just before calling Thread::exit() may not be processed by the event
loop. Make sure they get processed when finishing the thread, before
stopping.

This fixes a failure in the object-delete unit test.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 src/libcamera/base/thread.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/libcamera/base/thread.cpp b/src/libcamera/base/thread.cpp
index 75693c92a0b1..4ac72036aa69 100644
--- a/src/libcamera/base/thread.cpp
+++ b/src/libcamera/base/thread.cpp
@@ -371,6 +371,12 @@ void Thread::run()
 
 void Thread::finishThread()
 {
+	/*
+	 * Objects may have been scheduled for deletion right before the thread
+	 * exited. Ensure they get deleted now, before the thread stops.
+	 */
+	dispatchMessages(Message::Type::DeferredDelete);
+
 	data_->mutex_.lock();
 	data_->running_ = false;
 	data_->mutex_.unlock();
-- 
Regards,

Laurent Pinchart