From a59b69758bc1dddada9fe0ff5114fcdf44325f48 Mon Sep 17 00:00:00 2001
From: Norman Feske <norman.feske@genode-labs.com>
Date: Fri, 14 Aug 2020 16:30:36 +0200
Subject: [PATCH] sculpt: remove deferred GUI initialization

The sculpt manager used to defer the initialization of the GUI until
nitpicker's first display report became ready. This way, Sculpt was able
to run headlessly even if the framebuffer driver failed to start up.
Thanks to #3827, nitpicker no longer depends on a working framebuffer
driver. So the sculpt manager is safe to rely on nitpicker in any case,
simplifying the code.

Issue #3827
---
 repos/gems/run/sculpt.run                 |  4 --
 repos/gems/run/sculpt/nitpicker.config    |  2 +-
 repos/gems/src/app/sculpt_manager/main.cc | 62 +++++------------------
 3 files changed, 14 insertions(+), 54 deletions(-)

diff --git a/repos/gems/run/sculpt.run b/repos/gems/run/sculpt.run
index ddbe5e97a8..091d9ed1bf 100644
--- a/repos/gems/run/sculpt.run
+++ b/repos/gems/run/sculpt.run
@@ -73,8 +73,6 @@ install_config {
 			<policy label="nit_focus -> hover" report="nitpicker -> hover"/>
 			<policy label="slides_gui_fb_config -> slides"
 			        report="global_keys_handler -> slides"/>
-			<policy label="leitzentrale -> manager -> displays"
-			        report="nitpicker -> displays"/>
 		</config>
 	</start>
 
@@ -416,8 +414,6 @@ install_config {
 				<child name="report_fs_rom"/> </service>
 			<service name="ROM" label_prefix="manager -> config -> ">
 				<child name="config_fs_rom"/> </service>
-			<service name="ROM" label_prefix="manager -> displays">
-				<child name="report_rom"/> </service>
 			<service name="ROM" label_prefix="config -> ">
 				<child name="config_fs_rom"/> </service>
 			<service name="ROM" label="manager -> nitpicker_hover">
diff --git a/repos/gems/run/sculpt/nitpicker.config b/repos/gems/run/sculpt/nitpicker.config
index 3225b159de..1ac91f9301 100644
--- a/repos/gems/run/sculpt/nitpicker.config
+++ b/repos/gems/run/sculpt/nitpicker.config
@@ -1,6 +1,6 @@
 <config focus="rom">
 	<capture/> <event/>
-	<report hover="yes" focus="yes" clicked="yes" keystate="no" displays="yes"/>
+	<report hover="yes" focus="yes" clicked="yes" keystate="no"/>
 	<background color="#000000"/>
 
 	<domain name="pointer"      layer="1" content="client" label="no" origin="pointer" />
diff --git a/repos/gems/src/app/sculpt_manager/main.cc b/repos/gems/src/app/sculpt_manager/main.cc
index 8b00fc276f..386f4e3f6b 100644
--- a/repos/gems/src/app/sculpt_manager/main.cc
+++ b/repos/gems/src/app/sculpt_manager/main.cc
@@ -68,14 +68,16 @@ struct Sculpt::Main : Input_event_handler,
 
 	Registry<Child_state> _child_states { };
 
-	Constructible<Gui::Connection> _gui { };
+	Gui::Connection _gui { _env, "input" };
+
+	Gui::Root _gui_root { _env, _heap, *this };
 
 	Signal_handler<Main> _input_handler {
 		_env.ep(), *this, &Main::_handle_input };
 
 	void _handle_input()
 	{
-		_gui->input()->for_each_event([&] (Input::Event const &ev) {
+		_gui.input()->for_each_event([&] (Input::Event const &ev) {
 			handle_input_event(ev); });
 	}
 
@@ -984,44 +986,6 @@ struct Sculpt::Main : Input_event_handler,
 		_fb_drv_config.try_generate_manually_managed();
 	}
 
-	Attached_rom_dataspace _gui_displays { _env, "displays" };
-
-	Signal_handler<Main> _gui_displays_handler {
-		_env.ep(), *this, &Main::_handle_gui_displays };
-
-	void _handle_gui_displays()
-	{
-		_gui_displays.update();
-
-		if (!_gui_displays.xml().has_sub_node("display"))
-			return;
-
-		if (_gui.constructed())
-			return;
-
-		/*
-		 * Since the nitpicker GUI server has successfully issued the first
-		 * 'displays' report, there is a good chance that the framebuffer
-		 * driver is running. This is a good time to activate the GUI.
-		 */
-		_gui.construct(_env, "input");
-		_gui->input()->sigh(_input_handler);
-		_gui->mode_sigh(_gui_mode_handler);
-
-		/*
-		 * Adjust GUI parameters to initial GUI mode
-		 */
-		_handle_gui_mode();
-
-		/*
-		 * Avoid 'Constructible<Gui::Root>' because it requires the definition
-		 * of 'Gui::Session_component'.
-		 */
-		static Gui::Root gui_nitpicker(_env, _heap, *this);
-
-		generate_runtime_config();
-	}
-
 	void _handle_window_layout();
 
 	template <size_t N, typename FN>
@@ -1065,7 +1029,8 @@ struct Sculpt::Main : Input_event_handler,
 		_manual_deploy_rom.sigh(_manual_deploy_handler);
 		_runtime_state_rom.sigh(_runtime_state_handler);
 		_runtime_config_rom.sigh(_runtime_config_handler);
-		_gui_displays.sigh(_gui_displays_handler);
+		_gui.input()->sigh(_input_handler);
+		_gui.mode_sigh(_gui_mode_handler);
 
 		/*
 		 * Subscribe to reports
@@ -1087,6 +1052,7 @@ struct Sculpt::Main : Input_event_handler,
 		/*
 		 * Import initial report content
 		 */
+		_handle_gui_mode();
 		_storage.handle_storage_devices_update();
 		_deploy.handle_deploy();
 		_handle_pci_devices();
@@ -1137,9 +1103,6 @@ void Sculpt::Main::_handle_window_layout()
 
 	unsigned const log_min_w = 400;
 
-	if (!_gui.constructed())
-		return;
-
 	typedef String<128> Label;
 	Label const
 		inspect_label          ("runtime -> leitzentrale -> inspect"),
@@ -1168,7 +1131,11 @@ void Sculpt::Main::_handle_window_layout()
 	if (panel_height == 0)
 		return;
 
-	Framebuffer::Mode const mode = _gui->mode();
+	Framebuffer::Mode const mode = _gui.mode();
+
+	/* suppress intermediate boot-time states before the framebuffer driver is up */
+	if (mode.area.count() <= 1)
+		return;
 
 	/* area reserved for the panel */
 	Rect const panel(Point(0, 0), Area(mode.area.w(), panel_height));
@@ -1334,10 +1301,7 @@ void Sculpt::Main::_handle_window_layout()
 
 void Sculpt::Main::_handle_gui_mode()
 {
-	if (!_gui.constructed())
-		return;
-
-	Framebuffer::Mode const mode = _gui->mode();
+	Framebuffer::Mode const mode = _gui.mode();
 
 	_handle_window_layout();