PIObject::deleteLater important fix

PIWaitEvent::sleep() method
PITimer thread imp wait optimization, migrate to interruptable sleeps

libs/main/core/piobject.cpp

@@ -839,7 +839,7 @@ PIObject::Deleter::Deleter() {
 	PRIVATE->thread.setSlot([this](){
 		PIVector<PIObject*> oq;
 		PRIVATE->thread.lock();
-		while(PRIVATE->obj_queue.isEmpty()) PRIVATE->cond_var.wait(PRIVATE->thread.mutex());
+		PRIVATE->cond_var.wait(PRIVATE->thread.mutex());
 		oq.swap(PRIVATE->obj_queue);
 		PRIVATE->thread.unlock();
 		for (PIObject * o : oq) deleteObject(o);
@@ -851,7 +851,9 @@ PIObject::Deleter::Deleter() {
 PIObject::Deleter::~Deleter() {
 	//piCout << "~Deleter ...";
 	PRIVATE->thread.stop();
+	PRIVATE->thread.mutex().lock();
 	PRIVATE->cond_var.notifyAll();
+	PRIVATE->thread.mutex().unlock();
 	PRIVATE->thread.waitForFinish();
 	for (PIObject * o : PRIVATE->obj_queue) deleteObject(o);
 	//piCout << "~Deleter ok";

libs/main/core/piwaitevent_p.cpp

@@ -95,6 +95,27 @@ bool PIWaitEvent::wait(int fd, CheckRole role) {
 }
 
 
+bool PIWaitEvent::sleep(int us) {
+	if (!isCreate()) return false;
+#ifdef WINDOWS
+	DWORD ret = WaitForSingleObjectEx(event, us / 1000, TRUE);
+	ResetEvent(event);
+	return ret == WAIT_TIMEOUT;
+#else
+	int nfds = pipe_fd[ReadEnd] + 1;
+	FD_ZERO(&(fds[CheckRead]));
+	FD_SET(pipe_fd[ReadEnd], &(fds[CheckRead]));
+	timeval timeout;
+	timeout.tv_sec  = us / 1000000;
+	timeout.tv_usec = us % 1000000;
+	int ret = ::select(nfds, &(fds[CheckRead]), nullptr, nullptr, &timeout);
+	int buf = 0;
+	while (::read(pipe_fd[ReadEnd], &buf, sizeof(buf)) > 0);
+	return ret == 0;
+#endif
+}
+
+
 void PIWaitEvent::interrupt() {
 	if (!isCreate()) return;
 #ifdef WINDOWS

libs/main/core/piwaitevent_p.h

@@ -31,7 +31,7 @@
 #endif
 
 
-class PIWaitEvent {
+class PIP_EXPORT PIWaitEvent {
 public:
 	~PIWaitEvent();
 
@@ -44,6 +44,7 @@ public:
 	void create();
 	void destroy();
 	bool wait(int fd = -1, CheckRole role = CheckRead);
+	bool sleep(int us); // return if sleep done
 	void interrupt();
 	bool isCreate() const;
 	void * getEvent() const; // WINDOWS only