Fixed a factory output cleanup race (#1685)

* Fixed a factory output cleanup race

* Restored back lock in onStopped

* Build fix

Author: aleksandr-voitenko

obs-studio-server/source/osn-output.cpp

@@ -35,9 +35,15 @@ osn::Output::~Output() {}
 
 void osn::Output::InitOutput(obs_output_t *output)
 {
+	{
+		std::unique_lock lock(m_mtxOutputStop);
+		m_outputStopped = false;
+	}
+
 	auto onStopped = [](void *data, calldata_t *) {
 		osn::Output *context = reinterpret_cast<osn::Output *>(data);
 		std::unique_lock lock(context->m_mtxOutputStop);
+		context->m_outputStopped = true;
 		context->m_cvStop.notify_one();
 	};
 
@@ -69,10 +75,16 @@ void osn::Output::DeleteOutput()
 
 	blog(LOG_INFO, "osn::Output::DeleteOutput");
 
-	if (obs_output_active(m_output)) {
+	bool shouldWaitForStop = false;
+	{
+		std::unique_lock lock(m_mtxOutputStop);
+		shouldWaitForStop = obs_output_active(m_output) && !m_outputStopped;
+	}
+
+	if (shouldWaitForStop) {
 		obs_output_stop(m_output);
 		std::unique_lock lock(m_mtxOutputStop);
-		m_cvStop.wait_for(lock, std::chrono::seconds(20));
+		m_cvStop.wait_for(lock, std::chrono::seconds(20), [this] { return m_outputStopped; });
 	}
 	obs_output_release(m_output);
 	m_output = nullptr;
@@ -116,6 +128,11 @@ void osn::Output::StartOutput()
 	if (!m_output)
 		return;
 
+	{
+		std::unique_lock lock(m_mtxOutputStop);
+		m_outputStopped = false;
+	}
+
 	outdated_driver_error::instance()->set_active(true);
 	bool result = obs_output_start(m_output);
 	outdated_driver_error::instance()->set_active(false);
@@ -179,4 +196,4 @@ obs_output_t *osn::Output::GetOutput()
 const obs_output_t *osn::Output::GetOutput() const
 {
 	return m_output;
-}
+}

obs-studio-server/source/osn-output.hpp

@@ -68,8 +68,9 @@ class Output {
 
 	std::condition_variable m_cvStop;
 	std::mutex m_mtxOutputStop;
+	bool m_outputStopped = false;
 
 	const std::vector<std::string> m_signals;
 };
 
-}
+}