kconfig/lxdialog: let <ESC><ESC> behave as expected

<ESC><ESC> is used to step one back in the dialogs.
When lxdialog became built-in pressing <ESC> once would cause one step back
and pressing <ESC><ESC> would cause two steps back.
This patch - based on concept from Roman Zippel <zippel@linux-m68k.org> -
makes one <ESC> a noop and pressing <ESC><ESC> will cause one step backward.

In addition the final yes/no dialog now has the option to go back to the
the kernel configuration. So if you get too far out you can now go back
to configuring the kernel without saving and starting all over again.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

1 files changed, 14 insertions, 11 deletions

diff --git a/scripts/kconfig/mconf.c b/scripts/kconfig/mconf.c
index b1ad9a00ab19..ef75d6c3d3e5 100644
--- a/scripts/kconfig/mconf.c
+++ b/scripts/kconfig/mconf.c
@@ -608,7 +608,7 @@ static void conf(struct menu *menu)
                                   _(menu_instructions),
                                   rows, cols, rows - 10,
                                   active_menu, &s_scroll);
-                if (res == 1 || res == 255)
+                if (res == 1 || res == KEY_ESC)
                         break;
                 if (!item_activate_selected())
                         continue;
@@ -754,7 +754,7 @@ static void conf_choice(struct menu *menu)
                         } else
                                 show_help(menu);
                         break;
-                case 255:
+                case KEY_ESC:
                         return;
                 }
         }
@@ -794,7 +794,7 @@ static void conf_string(struct menu *menu)
                 case 1:
                         show_help(menu);
                         break;
-                case 255:
+                case KEY_ESC:
                         return;
                 }
         }
@@ -819,7 +819,7 @@ static void conf_load(void)
                 case 1:
                         show_helptext(_("Load Alternate Configuration"), load_config_help);
                         break;
-                case 255:
+                case KEY_ESC:
                         return;
                 }
         }
@@ -843,7 +843,7 @@ static void conf_save(void)
                 case 1:
                         show_helptext(_("Save Alternate Configuration"), save_config_help);
                         break;
-                case 255:
+                case KEY_ESC:
                         return;
                 }
         }
@@ -883,12 +883,15 @@ int main(int ac, char **av)
         init_wsize();
         reset_dialog();
         init_dialog(menu_backtitle);
-        conf(&rootmenu);
-        reset_dialog();
-        res = dialog_yesno(NULL,
-                           _("Do you wish to save your "
-                             "new kernel configuration?"),
-                           5, 60);
+        do {
+                conf(&rootmenu);
+                reset_dialog();
+                res = dialog_yesno(NULL,
+                                   _("Do you wish to save your "
+                                     "new kernel configuration?\n"
+                                     "<ESC><ESC> to continue."),
+                                   6, 60);
+        } while (res == KEY_ESC);
         end_dialog();
         if (res == 0) {
                 if (conf_write(NULL)) {