wayland: safely handle session lock surface destruction during unlock/DPMS

Author: Luke458

src/wayland/session_lock.cpp

@@ -142,13 +142,14 @@ void WlSessionLock::realizeLockTarget(WlSessionLock* old) {
 void WlSessionLock::unlock() {
 	if (this->isLocked()) {
 		this->lockTarget = false;
+
+		this->manager->unlock();
+
 		for (auto* surface: this->surfaces) {
 			delete surface;
 		}
 		this->surfaces.clear();
 
-		this->manager->unlock();
-
 		emit this->lockStateChanged();
 	}
 }
@@ -209,6 +210,7 @@ WlSessionLockSurface::WlSessionLockSurface(QObject* parent)
 
 WlSessionLockSurface::~WlSessionLockSurface() {
 	if (this->window != nullptr) {
+		this->window->destroy();
 		this->window->deleteLater();
 	}
 }

src/wayland/session_lock/session_lock.hpp

@@ -4,6 +4,7 @@
 #include <qtclasshelpermacros.h>
 #include <qtmetamacros.h>
 #include <qwindow.h>
+#include <qpointer.h>
 
 class QSWaylandSessionLock;
 class QSWaylandSessionLockSurface;
@@ -87,7 +88,7 @@ class LockWindowExtension: public QObject {
 
 private:
 	QSWaylandSessionLockSurface* surface = nullptr;
-	QSWaylandSessionLock* lock = nullptr;
+	QPointer<QSWaylandSessionLock> lock = nullptr;
 	bool immediatelyVisible = false;
 
 	friend class QSWaylandSessionLockSurface;

src/wayland/session_lock/surface.cpp

@@ -8,6 +8,7 @@
 #include <qobject.h>
 #include <qtversionchecks.h>
 #include <qtypes.h>
+#include <wayland-client.h>
 
 #include "lock.hpp"
 #include "session_lock.hpp"
@@ -38,8 +39,31 @@ QSWaylandSessionLockSurface::QSWaylandSessionLockSurface(QtWaylandClient::QWayla
 }
 
 QSWaylandSessionLockSurface::~QSWaylandSessionLockSurface() {
-	if (this->ext != nullptr) this->ext->surface = nullptr;
-	this->destroy();
+	bool shouldDestroyOnServer = true;
+
+	if (this->ext != nullptr) {
+		this->ext->surface = nullptr;
+		if (this->ext->lock == nullptr || !this->ext->lock->active()) {
+			shouldDestroyOnServer = false;
+		} else {
+			auto* qwindow = this->window() ? this->window()->window() : nullptr;
+			auto* screen = qwindow ? qwindow->screen() : nullptr;
+			auto* waylandScreen = screen ? dynamic_cast<QtWaylandClient::QWaylandScreen*>(screen->handle()) : nullptr;
+			if (waylandScreen == nullptr || waylandScreen->isPlaceholder() || waylandScreen->output() == nullptr) {
+				shouldDestroyOnServer = false;
+			}
+		}
+	} else {
+		shouldDestroyOnServer = false;
+	}
+
+	if (shouldDestroyOnServer) {
+		this->destroy();
+	} else {
+		if (auto* obj = this->object()) {
+			wl_proxy_destroy(reinterpret_cast<wl_proxy*>(obj));
+		}
+	}
 }
 
 bool QSWaylandSessionLockSurface::isExposed() const { return this->configured; }