A message looper can now have a death semaphore, ServerWindow now uses them.

ServerApp now waits up to 3 seconds for windows before killing them - it now
waits on the death semaphore, and only kills a window if it didn't quit fast
enough.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15147 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/MessageLooper.cpp

@@ -81,12 +81,28 @@ MessageLooper::Quit()
 	\brief Send a message to the looper without any attachments
 	\param code ID code of the message to post
 */
-void
+status_t
 MessageLooper::PostMessage(int32 code)
 {
 	BPrivate::LinkSender link(MessagePort());
 	link.StartMessage(code);
-	link.Flush();
+	return link.Flush();
+}
+
+
+/*static*/
+status_t
+MessageLooper::WaitForQuit(sem_id semaphore, bigtime_t timeout)
+{
+	status_t status;
+	do {
+		status = acquire_sem_etc(semaphore, 1, B_RELATIVE_TIMEOUT, timeout);
+	} while (status == B_INTERRUPTED);
+
+	if (status == B_TIMED_OUT)
+		return status;
+
+	return B_OK;
 }
 
 

src/servers/app/MessageLooper.h

@@ -22,12 +22,16 @@ class MessageLooper : public BLocker {
 		virtual	bool	Run();
 		virtual	void	Quit();
 
-		void			PostMessage(int32 code);
+		status_t		PostMessage(int32 code);
 		thread_id		Thread() const { return fThread; }
 		bool			IsQuitting() const { return fQuitting; }
+		sem_id			DeathSemaphore() const { return fDeathSemaphore; }
 
 		virtual port_id	MessagePort() const = 0;
 
+		static status_t	WaitForQuit(sem_id semaphore,
+							bigtime_t timeout = B_INFINITE_TIMEOUT);
+
 	private:
 		virtual void	_PrepareQuit();
 		virtual void	_GetLooperName(char* name, size_t length);
@@ -41,6 +45,7 @@ class MessageLooper : public BLocker {
 		thread_id		fThread;
 		BPrivate::PortLink fLink;
 		bool			fQuitting;
+		sem_id			fDeathSemaphore;
 };
 
 static const int32 kMsgQuitLooper = 'quit';

src/servers/app/ServerApp.cpp

@@ -146,51 +146,51 @@ ServerApp::~ServerApp(void)
 	if (!fQuitting)
 		CRITICAL("ServerApp: destructor called after Run()!\n");
 
-	fWindowListLock.Lock();
-
 	// quit all server windows
 
+	fWindowListLock.Lock();
 	for (int32 i = fWindowList.CountItems(); i-- > 0;) {
 		ServerWindow* window = fWindowList.ItemAt(i);
 		window->Quit();
 	}
-	int32 tries = fWindowList.CountItems() + 1;
-
 	fWindowListLock.Unlock();
 
 	// wait for the windows to quit
-	while (tries-- > 0) {
-		fWindowListLock.Lock();
-		if (fWindowList.CountItems() == 0) {
-			// we leave the list locked, doesn't matter anymore
-			break;
-		}
 
+	snooze(20000);
+
+	fWindowListLock.Lock();
+	for (int32 i = fWindowList.CountItems(); i-- > 0;) {
+		sem_id deathSemaphore = fWindowList.ItemAt(i)->DeathSemaphore();
 		fWindowListLock.Unlock();
-		snooze(10000);
-	}
 
-	if (tries < 0) {
-		// This really shouldn't happen, as it shows we're buggy
+		// wait 3 seconds for our window to quit - that's quite a long
+		// time, but killing it might have desastrous effects
+		if (MessageLooper::WaitForQuit(deathSemaphore, 3000000) != B_OK) {
+			// This really shouldn't happen, as it shows we're buggy
 #if __HAIKU__
-		syslog(LOG_ERR, "ServerApp %s needs to kill some server windows...\n", Signature());
+			syslog(LOG_ERR, "ServerApp %s needs to kill some server windows!\n",
+				Signature());
 #else
-		fprintf(stderr, "ServerApp %s needs to kill some server windows...\n", Signature());
+			printf("ServerApp %s needs to kill some server windows!\n",
+				Signature());
 #endif
 
-		// there still seem to be some windows left - kill them!
-		fWindowListLock.Lock();
+			// there still seem to be some windows left - kill them!
+			fWindowListLock.Lock();
 
-		for (int32 i = 0; i < fWindowList.CountItems(); i++) {
-			ServerWindow* window = fWindowList.ItemAt(i);
-			printf("kill window \"%s\"\n", window->Title());
+			for (int32 i = 0; i < fWindowList.CountItems(); i++) {
+				ServerWindow* window = fWindowList.ItemAt(i);
+				printf("kill window \"%s\"\n", window->Title());
 
-			kill_thread(window->Thread());
-			window->Hide();
-			delete window;
+				kill_thread(window->Thread());
+				window->Hide();
+				delete window;
+			}
+
+			fWindowListLock.Unlock();
 		}
-
-		fWindowListLock.Unlock();
+		fWindowListLock.Lock();
 	}
 
 	// first, make sure our monitor thread doesn't 

src/servers/app/ServerWindow.cpp

@@ -153,6 +153,8 @@ ServerWindow::ServerWindow(const char *title, ServerApp *app,
 		looperPort, B_PREFERRED_TOKEN);
 	BMessenger::Private(fHandlerMessenger).SetTo(fClientTeam,
 		looperPort, clientToken);
+
+	fDeathSemaphore = create_sem(0, "window death");
 }
 
 
@@ -173,6 +175,8 @@ ServerWindow::~ServerWindow()
 
 	delete fDirectWindowData;
 	STRACE(("#ServerWindow(%p) will exit NOW\n", this));
+
+	delete_sem(fDeathSemaphore);
 }