til_settings: always describe relevant settings

The existing iterative *_setup() interface only described
settings not found, quietly accepting usable settings already
present in the til_settings_t.

This worked fine for the existing interactive text setup thing,
but it's especially problematic for providing a GUI setup
frontend.

This commit makes it so the *_setup() methods always describe
undescribed settings they recognize, leaving the setup frontend
loop calling into the *_setup() methods to both apply the
description validation if wanted and actually tie the description
to respective setting returned by the _setup() methods as being
related to the returned description.

A new helper called til_settings_get_and_describe_value() has
been introduced primarily for use of module setup methods to
simplify this nonsense, replacing the til_settings_get_value()
calls and surrounding logic, but retaining the til_setting_desc_t
definitions largely verbatim.

This also results in discarding of some ad-hoc
til_setting_desc_check() calls, now that there's a centralized
place where settings become "described" (setup_interactively in
the case of rototiller).

Now a GUI frontend (like glimmer) would just provide its own
setup_interactively() equivalent for constructing its widgets for
a given *_setup() method's chain of returned descs.  Whereas in
the past this wasn't really feasible unless there was never going
to be pre-supplied settings.

I suspect the til_setting_desc_check() integration into
setup_interactively() needs more work, but I think this is good
enough for now and I'm out of spare time for the moment.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/til_fb.h b/src/til_fb.h
index 792c6e3..186324d 100644
--- a/src/til_fb.h
+++ b/src/til_fb.h
@@ -35,7 +35,7 @@ typedef struct til_fb_t til_fb_t;
 
 /* Supply this struct to fb_new() with the appropriate context */
 typedef struct til_fb_ops_t {
-	int	(*setup)(const til_settings_t *settings, til_setting_desc_t **next);
+	int	(*setup)(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc);
 	int	(*init)(const til_settings_t *settings, void **res_context);
 	void	(*shutdown)(til_fb_t *fb, void *context);
 	int	(*acquire)(til_fb_t *fb, void *context, void *page);