Convert servers to cooperative multitasking

4 files changed, 97 insertions, 66 deletions

diff --git a/clients/tde/src/app/remotemdi.cpp b/clients/tde/src/app/remotemdi.cpp
index 11ab75e..3ecf181 100644
--- a/clients/tde/src/app/remotemdi.cpp
+++ b/clients/tde/src/app/remotemdi.cpp
@@ -343,7 +343,12 @@ void RemoteMDI::childWindowCloseRequest(KMdiChildView *pWnd) {
 		// Give the child a chance to finish what it was doing and exit cleanly (i.e. without crashing!)
 		iview->closeConnections();
 		iview->hide();
-		KMdiMainFrm::childWindowCloseRequest(pWnd);
+
+		// RAJA FIXME
+		// Executing KMdiMainFrm::childWindowCloseRequest(pWnd) here will probably cause a crash
+		// We need to call this AFTER control has been returned to the main event loop at least once
+		// This is related to my lack of proper returning to the event loop, which MUST BE FIXED
+// 		KMdiMainFrm::childWindowCloseRequest(pWnd);	// RAJA UNCOMMENT ME
 	}
 }
 
@@ -363,11 +368,11 @@ void RemoteMDI::closeSpecifiedWindow(KMdiChildView *window) {
 	if (window) {
 		// Notify the status bar of the removal of the window
 		statusBar()->message(i18n("%1 removed").arg(window->tabCaption()));
-	
+
 		// We could also call removeWindowFromMdi, but it doesn't delete the
 		// pointer. This way, we're sure that the view will get deleted.
 		closeWindow(window);
-	
+
 		// Synchronize combo box
 		if (m_pCurrentWindow) {
 			currentChanged(m_pCurrentWindow);
diff --git a/clients/tde/src/app/views/instrumentview.cpp b/clients/tde/src/app/views/instrumentview.cpp
index 68b469a..ca3c853 100644
--- a/clients/tde/src/app/views/instrumentview.cpp
+++ b/clients/tde/src/app/views/instrumentview.cpp
@@ -15,6 +15,7 @@ InstrumentView::InstrumentView(const TQString &library, TQWidget *parentWidget,
 	: KMdiChildView(parentWidget, name, f)
 	, m_libraryName(library)
 	, m_instrumentPart( 0 )
+	, m_canary( NULL )
 {
 	init();
 }
@@ -23,12 +24,15 @@ InstrumentView::InstrumentView(const TQString &library, const TQString &caption,
 	: KMdiChildView(caption, parentWidget, name, f)
 	, m_libraryName(library)
 	, m_instrumentPart( 0 )
+	, m_canary( NULL )
 {
 	init();
 }
 
 InstrumentView::~InstrumentView() {
-	//
+	if (m_canary) {
+		*m_canary = true;
+	}
 }
 
 void InstrumentView::init() {
@@ -44,10 +48,13 @@ void InstrumentView::init() {
 }
 
 bool InstrumentView::queryExit() {
-	if( !m_instrumentPart )	//apparently std::exit() still calls this function, and abort() causes a crash..
+	if (!m_instrumentPart) {	// apparently std::exit() still calls this function, and abort() causes a crash..
 		return true;
+	}
 
+printf("[RAJA DEBUG 700.0] In InstrumentView::queryExit\n\r"); fflush(stdout);
 	m_instrumentPart->closeURL();
+printf("[RAJA DEBUG 700.1] In InstrumentView::queryExit\n\r"); fflush(stdout);
 
 	return true;
 }
@@ -57,11 +64,24 @@ void InstrumentView::closeConnections() {
 }
 
 void InstrumentView::connectServer(TQString server) {
+	if (!m_canary) {
+		m_canary = new bool;
+		*m_canary = false;
+	}
+	bool* canary = m_canary;
+
 	if (m_instrumentPart) {
-		if (m_instrumentPart->openURL(KURL(server))) {
-			close();
+		if (m_instrumentPart->openURL(KURL(server))) {		// This can call processEvents, therefore this object may not exist when it returns!
+			if (*canary == true) {
+				delete canary;
+				return;
+			}
+			TQTimer::singleShot(0, this, SLOT(close()));
 		}
 	}
+
+	delete m_canary;
+	m_canary = NULL;
 }
 
 /**********************************************
diff --git a/clients/tde/src/app/views/instrumentview.h b/clients/tde/src/app/views/instrumentview.h
index c9df8d2..64d4d5d 100644
--- a/clients/tde/src/app/views/instrumentview.h
+++ b/clients/tde/src/app/views/instrumentview.h
@@ -26,14 +26,15 @@ class InstrumentView : public KMdiChildView
 		void closeConnections();
 	
 	protected:
-		virtual void saveProperties( KConfig * );
-		virtual void readProperties( KConfig * );
+		virtual void saveProperties(KConfig *);
+		virtual void readProperties(KConfig *);
 		virtual bool queryExit();
 	
 	private:
 		void init();
 		TQString m_libraryName;
 		RemoteLab::InstrumentPart *m_instrumentPart;
+		bool* m_canary;
 };
 
 } // namespace RemoteLab
diff --git a/clients/tde/src/part/fpgaview/part.cpp b/clients/tde/src/part/fpgaview/part.cpp
index 4eae27d..52a1d92 100644
--- a/clients/tde/src/part/fpgaview/part.cpp
+++ b/clients/tde/src/part/fpgaview/part.cpp
@@ -46,12 +46,6 @@
 #include "floatspinbox.h"
 #include "layout.h"
 
-/* exception handling */
-struct exit_exception {
-	int c;
-	exit_exception(int c):c(c) { }
-};
-
 namespace RemoteLab {
 
 typedef KParts::GenericFactory<RemoteLab::FPGAViewPart> Factory;
@@ -82,7 +76,7 @@ FPGAViewPart::FPGAViewPart(TQWidget *parentWidget, const char *widgetName, TQObj
 
 FPGAViewPart::~FPGAViewPart() {
 	if (m_connectionMutex->locked()) {
-		throw exit_exception(-1);
+		printf("[WARNING] Exiting when data transfer still in progress!\n\r"); fflush(stdout);
 	}
 
 	if (m_socket) {
@@ -95,11 +89,14 @@ FPGAViewPart::~FPGAViewPart() {
 }
 
 void FPGAViewPart::processLockouts() {
-	if ((m_socket) && (m_socket->state() == TQSocket::Connected)) {
-		widget()->setEnabled(true);
-	}
-	else {
-		widget()->setEnabled(false);
+	TQWidget* mainWidget = widget();
+	if (mainWidget) {
+		if ((m_socket) && (m_socket->state() == TQSocket::Connected)) {
+			mainWidget->setEnabled(true);
+		}
+		else {
+			mainWidget->setEnabled(false);
+		}
 	}
 }
 
@@ -114,22 +111,27 @@ void FPGAViewPart::postInit() {
 bool FPGAViewPart::openURL(const KURL &url) {
 	int ret;
 	ret = connectToServer(url.url());
+	// RAJA FIXME
+	// Need canary?
 	processLockouts();
 	return (ret != 0);
 }
 
 bool FPGAViewPart::closeURL() {
-	if (m_connectionMutex->locked()) {
-		throw exit_exception(-1);
-	}
-
+printf("[RAJA DEBUG 710.0] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
+printf("[RAJA DEBUG 710.1] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
 	if (m_socket) {
 		m_socket->clearPendingData();
+printf("[RAJA DEBUG 710.2] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
 		m_socket->close();
-		delete m_socket;
+printf("[RAJA DEBUG 710.3] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
+		m_socket->deleteLater();
+printf("[RAJA DEBUG 710.4] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
 		m_socket = NULL;
+printf("[RAJA DEBUG 710.5] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
 	}
 
+printf("[RAJA DEBUG 710.6] In FPGAViewPart::closeURL\n\r"); fflush(stdout);
 	processLockouts();
 
 	m_url = KURL();
@@ -138,6 +140,11 @@ bool FPGAViewPart::closeURL() {
 }
 
 int FPGAViewPart::connectToServer(TQString server) {
+printf("[RAJA DEBUG 200.0] In FPGAViewPart::connectToServer\n\r"); fflush(stdout);
+	if (m_socket) {
+printf("[RAJA DEBUG 200.1] In FPGAViewPart::connectToServer TRIED TO CONNECT TWICE!!!\n\r"); fflush(stdout);
+		return -1;
+	}
 	if (!m_socket) {
 		m_socket = new TDEKerberosClientSocket(this);
 	}
@@ -146,63 +153,61 @@ int FPGAViewPart::connectToServer(TQString server) {
 	m_socket->connectToHost(server, 4004);
 	while ((m_socket->state() != TQSocket::Connected) && (m_socket->state() != TQSocket::Idle)) {
 		tqApp->eventLoop()->processEvents(TQEventLoop::AllEvents);
+		if (!m_socket) return -1; 	// Any entry into the event loop could end up deleting the socket object depending on user interaction
 	}
 	if (m_socket->state() != TQSocket::Connected) {
 		return -1;
 	}
 	if (m_socket->setUsingKerberos(true) != 0) {
+		if (!m_socket) return -1; 	// Any entry into the event loop could end up deleting the socket object depending on user interaction
 		m_socket->close();
 		KMessageBox::error(0, i18n("<qt>Unable to establish Kerberos protocol with remote server<p>Please verify that you currently hold a valid Kerberos ticket</qt>"), i18n("Connection Failed"));
 		return -1;
 	}
 	connect(m_socket, SIGNAL(connectionClosed()), this, SLOT(connectionClosed()));
-	try {
-		m_connectionMutex->lock();
-		TQString response;
-		TQDataStream ds(m_socket);
-		// Read magic number and proto version from server
-		TQ_UINT32 magicnum;
-		TQ_UINT32 protover;
-		ds >> magicnum;
-		ds >> protover;
-		printf("[DEBUG] Got magic number %d and protocol version %d\n\r", magicnum, protover); fflush(stdout);
-		// Request connection to backend server
-		ds << TQString("SERV");
-		ds << TQString(CLIENT_LIBRARY);
-		ds >> response;
-printf("[RAJA DEBUG 400.0] Got '%s' from the server\n\r", response.ascii()); fflush(stdout);
-		if (response == "OK") {
-			m_connectionMutex->unlock();
-			return 0;
-		}
-		else if (response == "ERRNOCONN") {
-			KMessageBox::error(0, i18n("<qt>Unable to establish connection with backend server<p>Please verify that you are currently connected to a workspace</qt>"), i18n("Connection Failed"));
-			m_connectionMutex->unlock();
-			return -1;
-		}
-		else if (response == "ERRNOTAVL") {
-			KMessageBox::error(0, i18n("<qt>The backend server is not available at this time<p>Please try a different workspace, or try again later</qt>"), i18n("Connection Failed"));
-			m_connectionMutex->unlock();
-			return -1;
-		}
-		else if (response == "ERRNOSERV") {
-			KMessageBox::error(0, i18n("<qt>The active laboratory workspace does not support the requested service</qt>"), i18n("Service Unavailable"));
-			m_connectionMutex->unlock();
-			return -1;
-		}
-		else {
-			KMessageBox::error(0, i18n("<qt>Unable to establish connection with remote server</qt>"), i18n("Connection Failed"));
-			m_connectionMutex->unlock();
-			return -1;
-		}
 
+	// Kerberos connection established!
+	m_connectionMutex->lock();
+	TQString response;
+	TQDataStream ds(m_socket);
+	// Read magic number and proto version from server
+	TQ_UINT32 magicnum;
+	TQ_UINT32 protover;
+	ds >> magicnum;
+	ds >> protover;
+	printf("[DEBUG] Got magic number %d and protocol version %d\n\r", magicnum, protover); fflush(stdout);
+	// Request connection to backend server
+	ds << TQString("SERV");
+	ds << TQString(CLIENT_LIBRARY);
+	ds >> response;
+printf("[RAJA DEBUG 400.0] Got '%s' from the server\n\r", response.ascii()); fflush(stdout);
+	if (response == "OK") {
 		m_connectionMutex->unlock();
 		return 0;
 	}
-	catch (exit_exception& e) {
+	else if (response == "ERRNOCONN") {
+		KMessageBox::error(0, i18n("<qt>Unable to establish connection with backend server<p>Please verify that you are currently connected to a workspace</qt>"), i18n("Connection Failed"));
+		m_connectionMutex->unlock();
+		return -1;
+	}
+	else if (response == "ERRNOTAVL") {
+		KMessageBox::error(0, i18n("<qt>The backend server is not available at this time<p>Please try a different workspace, or try again later</qt>"), i18n("Connection Failed"));
 		m_connectionMutex->unlock();
 		return -1;
 	}
+	else if (response == "ERRNOSERV") {
+		KMessageBox::error(0, i18n("<qt>The active laboratory workspace does not support the requested service</qt>"), i18n("Service Unavailable"));
+		m_connectionMutex->unlock();
+		return -1;
+	}
+	else {
+		KMessageBox::error(0, i18n("<qt>Unable to establish connection with remote server</qt>"), i18n("Connection Failed"));
+		m_connectionMutex->unlock();
+		return -1;
+	}
+
+	m_connectionMutex->unlock();
+	return 0;
 }
 
 void FPGAViewPart::updateDisplay() {