From 24d5f1a6249b08a8b21854ecf001be7e07e5bf23 Mon Sep 17 00:00:00 2001
From: Robin Gareus <robin@gareus.org>
Date: Thu, 11 May 2017 14:20:33 +0200
Subject: [PATCH] Tweak/fix splash screen event-loop

Prevent possible endless loop in Splash::display() and handle
some related edge-cases and race conditions WRT expose_done
and is_visible().
---
 gtk2_ardour/ardour_ui.cc |  4 ++--
 gtk2_ardour/splash.cc    | 28 +++++++++++++++++++++-------
 gtk2_ardour/splash.h     |  4 +++-
 3 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/gtk2_ardour/ardour_ui.cc b/gtk2_ardour/ardour_ui.cc
index d01a92ebf6..f48d4f527d 100644
--- a/gtk2_ardour/ardour_ui.cc
+++ b/gtk2_ardour/ardour_ui.cc
@@ -1282,7 +1282,7 @@ ARDOUR_UI::starting ()
 
 	BootMessage (string_compose (_("%1 is ready for use"), PROGRAM_NAME));
 
-	if (splash && splash->is_visible()) {
+	if (splash) {
 		// in 1 second, hide the splash screen
 		Glib::signal_timeout().connect (sigc::bind (sigc::ptr_fun (_hide_splash), this), 1000);
 	}
@@ -1927,7 +1927,7 @@ ARDOUR_UI::open_recent_session ()
 
 		can_return = false;
 	}
-	if (splash && splash->is_visible()) {
+	if (splash) {
 		// in 1 second, hide the splash screen
 		Glib::signal_timeout().connect (sigc::bind (sigc::ptr_fun (_hide_splash), this), 1000);
 	}
diff --git a/gtk2_ardour/splash.cc b/gtk2_ardour/splash.cc
index 744a49fa4f..756749c6e6 100644
--- a/gtk2_ardour/splash.cc
+++ b/gtk2_ardour/splash.cc
@@ -21,6 +21,7 @@
 
 #include "pbd/failed_constructor.h"
 #include "pbd/file_utils.h"
+#include "pbd/stacktrace.h"
 
 #include "ardour/ardour.h"
 #include "ardour/filesystem_paths.h"
@@ -99,6 +100,9 @@ Splash::Splash ()
 
 Splash::~Splash ()
 {
+	idle_connection.disconnect ();
+	expose_done = true;
+	hide ();
 	the_splash = 0;
 }
 
@@ -129,11 +133,19 @@ Splash::pop_back_for (Gtk::Window& win)
 void
 Splash::pop_front ()
 {
-#if defined  __APPLE__ || defined PLATFORM_WINDOWS
 	if (get_window()) {
+#if defined  __APPLE__ || defined PLATFORM_WINDOWS
 		show ();
-	}
+#else
+		gdk_window_restack(get_window()->gobj(), NULL, true);
 #endif
+	}
+}
+
+void
+Splash::hide ()
+{
+	Gtk::Window::hide();
 }
 
 void
@@ -182,8 +194,9 @@ Splash::expose (GdkEventExpose* ev)
 	 */
 
 	if (expose_is_the_one) {
-		Glib::signal_idle().connect (sigc::mem_fun (this, &Splash::idle_after_expose),
-					     GDK_PRIORITY_REDRAW+2);
+		idle_connection = Glib::signal_idle().connect (
+				sigc::mem_fun (this, &Splash::idle_after_expose),
+				GDK_PRIORITY_REDRAW+2);
 	}
 
 	return true;
@@ -216,7 +229,7 @@ Splash::display ()
 	present ();
 
 	if (!was_mapped) {
-		while (!expose_done) {
+		while (!expose_done && gtk_events_pending()) {
 			gtk_main_iteration ();
 		}
 		gdk_display_flush (gdk_display_get_default());
@@ -236,13 +249,14 @@ Splash::message (const string& msg)
 	Glib::RefPtr<Gdk::Window> win = darea.get_window();
 
 	if (win) {
-		expose_done = false;
-
 		if (win->is_visible ()) {
 			win->invalidate_rect (Gdk::Rectangle (0, darea.get_height() - 30, darea.get_width(), 30), true);
 		} else {
 			darea.queue_draw ();
 		}
+		if (expose_done) {
+			ARDOUR::GUIIdle ();
+		}
 	}
 }
 
diff --git a/gtk2_ardour/splash.h b/gtk2_ardour/splash.h
index d92c443cf0..109b68a8be 100644
--- a/gtk2_ardour/splash.h
+++ b/gtk2_ardour/splash.h
@@ -47,6 +47,7 @@ public:
 	void on_realize ();
 	bool on_map_event (GdkEventAny*);
 	void message (const std::string& msg);
+	void hide ();
 
 private:
 	static Splash* the_splash;
@@ -58,7 +59,8 @@ private:
 	void boot_message (std::string);
 	PBD::ScopedConnection msg_connection;
 
-	bool expose_done;
+	sigc::connection idle_connection;
+	volatile bool expose_done;
 	bool expose_is_the_one;
 	bool idle_after_expose ();
 };
-- 
2.30.2