[gnome-session] fail-whale-dialog: Make dialog visible in all monitors

[Ray Strode <halfline src gnome org>]

commit cc861459e77940b281dae16a75e109fd5d763848
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Tue Feb 12 01:55:44 2019 +0100

    fail-whale-dialog: Make dialog visible in all monitors
    
    In multi-monitor setups show the fail dialog in all visible monitors instead
    of only showing in the primary that might not work, or might allow the user
    to still interact with the Shell if the session stopped running at application
    level.

 gnome-session/gsm-fail-whale-dialog.c | 92 +++++++++++++++++++++++++++--------
 1 file changed, 73 insertions(+), 19 deletions(-)
---
diff --git a/gnome-session/gsm-fail-whale-dialog.c b/gnome-session/gsm-fail-whale-dialog.c
index 064935f9..bf517b85 100644
--- a/gnome-session/gsm-fail-whale-dialog.c
+++ b/gnome-session/gsm-fail-whale-dialog.c
@@ -43,6 +43,7 @@ struct _GsmFailWhaleDialog
         gboolean debug_mode;
         gboolean allow_logout;
         gboolean extensions;
+        GdkMonitor *monitor;
         GdkRectangle geometry;
 };
 
@@ -107,13 +108,7 @@ _window_move_resize_window (GsmFailWhaleDialog *window,
 static void
 update_geometry (GsmFailWhaleDialog *fail_dialog)
 {
-        GdkDisplay *display;
-        GdkMonitor *monitor;
-
-        display = gtk_widget_get_display (GTK_WIDGET (fail_dialog));
-        monitor = gdk_display_get_primary_monitor (display);
-
-        gdk_monitor_get_geometry (monitor, &fail_dialog->geometry);
+        gdk_monitor_get_geometry (fail_dialog->monitor, &fail_dialog->geometry);
 }
 
 static void
@@ -273,7 +268,9 @@ setup_window (GsmFailWhaleDialog *fail_dialog)
         GtkWidget *button_box;
         GtkWidget *button;
         GdkPixbuf *fail_icon;
+        GdkDisplay *display;
         char *markup;
+        int i;
 
         gtk_window_set_title (GTK_WINDOW (fail_dialog), "");
         gtk_window_set_icon_name (GTK_WINDOW (fail_dialog), GSM_ICON_COMPUTER_FAIL);
@@ -282,8 +279,19 @@ setup_window (GsmFailWhaleDialog *fail_dialog)
         gtk_window_set_keep_above (GTK_WINDOW (fail_dialog), TRUE);
         gtk_window_stick (GTK_WINDOW (fail_dialog));
         gtk_window_set_position (GTK_WINDOW (fail_dialog), GTK_WIN_POS_CENTER_ALWAYS);
+
         /* only works if there is a window manager which is unlikely */
-        gtk_window_fullscreen (GTK_WINDOW (fail_dialog));
+        display = gtk_widget_get_display (GTK_WIDGET (fail_dialog));
+        for (i = 0; i < gdk_display_get_n_monitors (display); i++) {
+                if (gdk_display_get_monitor (display, i) == fail_dialog->monitor) {
+                        GdkScreen *screen;
+
+                        screen = gtk_widget_get_screen (GTK_WIDGET (fail_dialog));
+                        gtk_window_fullscreen_on_monitor (GTK_WINDOW (fail_dialog),
+                                                          screen, i);
+                        break;
+                }
+        }
 
         box = gtk_box_new (GTK_ORIENTATION_VERTICAL, 10);
         gtk_widget_set_valign (box, GTK_ALIGN_CENTER);
@@ -347,6 +355,53 @@ gsm_fail_whale_dialog_init (GsmFailWhaleDialog *fail_dialog)
 static gboolean debug_mode = FALSE;
 static gboolean allow_logout = FALSE;
 static gboolean extensions = FALSE;
+static GList *dialogs = NULL;
+
+static void
+create_fail_dialog (GdkMonitor *monitor)
+{
+        GsmFailWhaleDialog *fail_dialog;
+
+        fail_dialog = g_object_new (GSM_TYPE_FAIL_WHALE_DIALOG, NULL);
+        fail_dialog->debug_mode = debug_mode;
+        fail_dialog->allow_logout = allow_logout;
+        fail_dialog->extensions = extensions;
+        fail_dialog->monitor = monitor;
+
+        setup_window (fail_dialog);
+
+        g_signal_connect (fail_dialog, "destroy",
+                          G_CALLBACK (gtk_main_quit), NULL);
+
+        gtk_widget_show (GTK_WIDGET (fail_dialog));
+
+        dialogs = g_list_prepend (dialogs, fail_dialog);
+}
+
+static void
+on_monitor_added (GdkDisplay  *display,
+                  GdkMonitor  *monitor)
+{
+        create_fail_dialog (monitor);
+}
+
+static void
+on_monitor_removed (GdkDisplay  *display,
+                    GdkMonitor  *monitor)
+{
+        GList *l;
+
+        for (l = dialogs; l;) {
+                GList *next = l->next;
+                GsmFailWhaleDialog *fail_dialog = l->data;
+
+                if (fail_dialog->monitor == monitor) {
+                        dialogs = g_list_delete_link (dialogs, l);
+                        gtk_widget_destroy (GTK_WIDGET (fail_dialog));
+                }
+                l = next;
+        }
+}
 
 int main (int argc, char *argv[])
 {
@@ -357,8 +412,9 @@ int main (int argc, char *argv[])
                 { NULL, 0, 0, 0, NULL, NULL, NULL }
         };
 
-        GsmFailWhaleDialog        *fail_dialog;
         GError *error = NULL;
+        GdkDisplay *display;
+        int i;
 
         bindtextdomain (GETTEXT_PACKAGE, LOCALE_DIR);
         bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
@@ -385,17 +441,15 @@ int main (int argc, char *argv[])
         if (g_strcmp0 (g_getenv ("RUNNING_UNDER_GDM"), "true") == 0)
                 allow_logout = FALSE;
 
-        fail_dialog = g_object_new (GSM_TYPE_FAIL_WHALE_DIALOG, NULL);
-        fail_dialog->debug_mode = debug_mode;
-        fail_dialog->allow_logout = allow_logout;
-        fail_dialog->extensions = extensions;
-
-        setup_window (fail_dialog);
-
-        g_signal_connect (fail_dialog, "destroy",
-                          G_CALLBACK (gtk_main_quit), NULL);
+        display = gdk_display_get_default ();
+        for (i = 0; i < gdk_display_get_n_monitors (display); i++) {
+                create_fail_dialog (gdk_display_get_monitor (display, i));
+        }
 
-        gtk_widget_show (GTK_WIDGET (fail_dialog));
+        g_signal_connect (display, "monitor-added",
+                          G_CALLBACK (on_monitor_added), &dialogs);
+        g_signal_connect (display, "monitor-removed",
+                          G_CALLBACK (on_monitor_removed), &dialogs);
 
         gtk_main ();