first pass at no close/open/new when disconnected from JACK, including noting that JACK is disconnected from the shutdown callback

git-svn-id: svn://localhost/ardour2/trunk@1757 d708f5d6-7413-0410-9779-e7cbd77b26cf

gtk2_ardour/ardour_ui.cc

@@ -947,9 +947,30 @@ ARDOUR_UI::filter_ardour_session_dirs (const FileFilter::Info& info)
 	return S_ISREG (statbuf.st_mode);
 }
 
+bool
+ARDOUR_UI::check_audioengine ()
+{
+	if (engine) {
+		if (!engine->connected()) {
+			MessageDialog msg (_("Ardour is not connected to JACK\n"
+					     "You cannot open or close sessions in this condition"));
+			msg.run ();
+			return false;
+		}
+		return true;
+	} else {
+		return false;
+	}
+}
+
 void
 ARDOUR_UI::open_session ()
 {
+	if (!check_audioengine()) {
+		return;
+		
+	}
+
 	/* popup selector window */
 
 	if (open_session_selector == 0) {
@@ -1751,9 +1772,7 @@ ARDOUR_UI::new_session (std::string predetermined_path)
 	string session_name;
 	string session_path;
 
-	if (!engine->connected()) {
-		MessageDialog msg (_("Ardour is not connected to JACK at this time. Creating new sessions is not possible."));
-		msg.run ();
+	if (!check_audioengine()) {
 		return false;
 	}
 
@@ -1768,10 +1787,8 @@ ARDOUR_UI::new_session (std::string predetermined_path)
 	do {
 	        response = new_session_dialog->run ();
 
-		if (!engine->connected()) {
+		if (!check_audioengine()) {
 			new_session_dialog->hide ();
-			MessageDialog msg (_("Ardour is not connected to JACK at this time. Creating new sessions is not possible."));
-			msg.run ();
 			return false;
 		}
 		
@@ -1964,6 +1981,10 @@ ARDOUR_UI::new_session (std::string predetermined_path)
 void
 ARDOUR_UI::close_session()
 {
+	if (!check_audioengine()) {
+		return;
+	}
+
 	unload_session();
 	new_session ();
 }
@@ -1975,6 +1996,10 @@ ARDOUR_UI::load_session (const string & path, const string & snap_name, string*
 	int x;
 	session_loaded = false;
 	
+	if (!check_audioengine()) {
+		return -1;
+	}
+
 	x = unload_session ();
 
 	if (x < 0) {
@@ -2031,8 +2056,14 @@ ARDOUR_UI::build_session (const string & path, const string & snap_name,
 	Session *new_session;
 	int x;
 
+	if (!check_audioengine()) {
+		return -1;
+	}
+
 	session_loaded = false;
+
 	x = unload_session ();
+
 	if (x < 0) {
 		return -1;
 	} else if (x > 0) {

gtk2_ardour/ardour_ui.h

@@ -257,6 +257,8 @@ class ARDOUR_UI : public Gtkmm2ext::UI
 	ARDOUR::AudioEngine                 *engine;
 	ARDOUR::Session                     *session;
 
+	bool check_audioengine();
+
 	Gtk::Tooltips          _tooltips;
 
 	void                     goto_editor_window ();

libs/ardour/audioengine.cc

@@ -762,6 +762,7 @@ AudioEngine::halted (void *arg)
 	ae->_running = false;
 	ae->_buffer_size = 0;
 	ae->_frame_rate = 0;
+	ae->_jack = 0;
 
 	ae->Halted(); /* EMIT SIGNAL */
 }