ui/ncurses: Improve update handling in nested screens

Several screens in petitboot-nc require an update if a config or sysinfo
update is received. However if those screens exist but are not the
current screen they will incorrectly try to draw to the screen.

Where the currently active screen is a textscreen (eg. a help screen)
the update is delayed until after the screen is exited.

In the particular case of nc-config where the current screen can be an
nc-subset screen, the nc-subset screen is exited immediately so the
update can be performed, since the nc-subset screen depends on the
information in the previous screen.

Signed-off-by: Samuel Mendoza-Jonas <sam.mj@au1.ibm.com>

1 files changed, 30 insertions, 15 deletions

diff --git a/ui/ncurses/nc-config.c b/ui/ncurses/nc-config.c
index b257076..7c02250 100644
--- a/ui/ncurses/nc-config.c
+++ b/ui/ncurses/nc-config.c
@@ -53,6 +53,7 @@ struct config_screen {
 	bool			show_help;
 	bool			show_subset;
 	bool			need_redraw;
+	bool			need_update;
 
 	void			(*on_exit)(struct cui *);
 
@@ -170,21 +171,6 @@ static void config_screen_resize(struct nc_scr *scr)
 	(void)screen;
 }
 
-static int config_screen_post(struct nc_scr *scr)
-{
-	struct config_screen *screen = config_screen_from_scr(scr);
-	screen->show_subset = false;
-	widgetset_post(screen->widgetset);
-	nc_scr_frame_draw(scr);
-	if (screen->need_redraw) {
-		redrawwin(scr->main_ncw);
-		screen->need_redraw = false;
-	}
-	wrefresh(screen->scr.main_ncw);
-	pad_refresh(screen);
-	return 0;
-}
-
 static int config_screen_unpost(struct nc_scr *scr)
 {
 	struct config_screen *screen = config_screen_from_scr(scr);
@@ -1014,10 +1000,38 @@ void config_screen_update(struct config_screen *screen,
 		const struct config *config,
 		const struct system_info *sysinfo)
 {
+	if (screen->cui->current != config_screen_scr(screen)) {
+		screen->need_update = true;
+		return;
+	}
+
 	config_screen_draw(screen, config, sysinfo);
 	pad_refresh(screen);
 }
 
+static int config_screen_post(struct nc_scr *scr)
+{
+	struct config_screen *screen = config_screen_from_scr(scr);
+	screen->show_subset = false;
+
+	if (screen->need_update) {
+		config_screen_draw(screen, screen->cui->config,
+				   screen->cui->sysinfo);
+		screen->need_update = false;
+	} else {
+		widgetset_post(screen->widgetset);
+	}
+
+	nc_scr_frame_draw(scr);
+	if (screen->need_redraw) {
+		redrawwin(scr->main_ncw);
+		screen->need_redraw = false;
+	}
+	wrefresh(screen->scr.main_ncw);
+	pad_refresh(screen);
+	return 0;
+}
+
 static int config_screen_destroy(void *arg)
 {
 	struct config_screen *screen = arg;
@@ -1043,6 +1057,7 @@ struct config_screen *config_screen_init(struct cui *cui,
 	screen->cui = cui;
 	screen->on_exit = on_exit;
 	screen->need_redraw = false;
+	screen->need_update = false;
 	screen->label_x = 2;
 	screen->field_x = 17;