Ensure kdesktop signal handlers execute in the main GUI thread

(cherry picked from commit 755776b6c4)

kdesktop/CMakeLists.txt

@@ -95,7 +95,7 @@ set( ${target}_SRCS
 tde_add_tdeinit_executable( ${target} AUTOMOC
   SOURCES ${${target}_SRCS}
   LINK
-    kdesktopsettings-static bgnd-static dmctl-static
+    pthread kdesktopsettings-static bgnd-static dmctl-static
     konq-shared tdeutils-shared
     ${XRENDER_LIBRARIES} ${XCURSOR_LIBRARIES} Xext ${DL_LIBRARIES}
     ${XSS_LIBRARIES} ${DBUS_1_TQT_LIBRARIES}

kdesktop/krootwm.cc

@@ -77,10 +77,12 @@ KRootWm::KRootWm(KDesktop* _desktop) : TQObject(_desktop), startup(FALSE)
   m_helperThread->start();
   m_threadHelperObject = new KRootWmThreadHelperObject;
   m_threadHelperObject->moveToThread(m_helperThread);
+  connect(this, TQT_SIGNAL(initializeHelperThread()), m_threadHelperObject, TQT_SLOT(initializeThread()));
   connect(this, TQT_SIGNAL(terminateHelperThread()), m_threadHelperObject, TQT_SLOT(terminateThread()));
   connect(this, TQT_SIGNAL(asyncLock()), m_threadHelperObject, TQT_SLOT(slotLock()));
   connect(this, TQT_SIGNAL(asyncLockAndDoNewSession()), m_threadHelperObject, TQT_SLOT(lockAndDoNewSession()));
   connect(this, TQT_SIGNAL(asyncSlotSessionActivated(int)), m_threadHelperObject, TQT_SLOT(slotSessionActivated(int)));
+  initializeHelperThread();
 
   s_rootWm = this;
   m_actionCollection = new TDEActionCollection(_desktop, this, "KRootWm::m_actionCollection");
@@ -880,6 +882,16 @@ void KRootWm::slotPopulateSessions()
         }
 }
 
+void KRootWmThreadHelperObject::initializeThread() {
+	// Prevent kdesktop_lock signals from being handled by the wrong (non-GUI) thread
+	sigset_t set;
+	sigemptyset(&set);
+	sigaddset(&set, SIGUSR1);
+	sigaddset(&set, SIGUSR2);
+	sigaddset(&set, SIGTTIN);
+	pthread_sigmask(SIG_BLOCK, &set, NULL);
+}
+
 void KRootWmThreadHelperObject::terminateThread() {
 	TQEventLoop* eventLoop = TQApplication::eventLoop();
 	if (eventLoop) {

kdesktop/krootwm.h

@@ -127,6 +127,7 @@ public slots:
   void slotLockNNewSession();
 
 signals:
+  void initializeHelperThread();
   void terminateHelperThread();
   void asyncLock();
   void asyncLockAndDoNewSession();
@@ -192,6 +193,7 @@ class KRootWmThreadHelperObject : public TQObject
 	TQ_OBJECT
 
 	public slots:
+		void initializeThread();
 		void terminateThread();
 		void slotLock();
 		void lockAndDoNewSession();