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.

7 files changed, 268 insertions, 314 deletions

diff --git a/src/modules/compose/compose.c b/src/modules/compose/compose.c
index bf3f125..81406c1 100644
--- a/src/modules/compose/compose.c
+++ b/src/modules/compose/compose.c
@@ -39,7 +39,7 @@ typedef struct compose_context_t {
 static void * compose_create_context(unsigned ticks, unsigned num_cpus);
 static void compose_destroy_context(void *context);
 static void compose_prepare_frame(void *context, unsigned ticks, unsigned n_cpus, til_fb_fragment_t *fragment, til_fragmenter_t *res_fragmenter);
-static int compose_setup(const til_settings_t *settings, til_setting_desc_t **next_setting);
+static int compose_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc);
 
 static char	*compose_default_layers[] = { "drizzle", "stars", "spiro", "plato", NULL };
 static char	**compose_layers;
@@ -111,32 +111,30 @@ static void compose_prepare_frame(void *context, unsigned ticks, unsigned n_cpus
 }
 
 
-static int compose_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int compose_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
 	const char	*layers;
-
-	layers = til_settings_get_value(settings, "layers");
-	if (!layers) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Colon-Separated List Of Module Layers, In Draw Order",
-						.key = "layers",
-						.preferred = "drizzle:stars:spiro:plato",
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Colon-Separated List Of Module Layers, In Draw Order",
+							.key = "layers",
+							.preferred = "drizzle:stars:spiro:plato",
+							.annotations = NULL
+						},
+						&layers,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	/* turn layers colon-separated list into a null-terminated array of strings */
 	{
 		const til_module_t	**modules;
-		size_t				n_modules;
-		char				*toklayers, *layer;
-		int				n = 2;
+		size_t			n_modules;
+		char			*toklayers, *layer;
+		int			n = 2;
 
 		til_get_modules(&modules, &n_modules);
 
diff --git a/src/modules/drizzle/drizzle.c b/src/modules/drizzle/drizzle.c
index a637368..b634a5e 100644
--- a/src/modules/drizzle/drizzle.c
+++ b/src/modules/drizzle/drizzle.c
@@ -153,7 +153,7 @@ static void drizzle_render_fragment(void *context, unsigned ticks, unsigned cpu,
 }
 
 
-static int drizzle_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int drizzle_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
 	const char	*viscosity;
 	const char	*values[] = {
@@ -163,24 +163,22 @@ static int drizzle_setup(const til_settings_t *settings, til_setting_desc_t **ne
 				".05",
 				NULL
 			};
-
-	viscosity = til_settings_get_value(settings, "viscosity");
-	if (!viscosity) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Puddle Viscosity",
-						.key = "viscosity",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(DEFAULT_VISCOSITY),
-						.values = values,
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Puddle Viscosity",
+							.key = "viscosity",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(DEFAULT_VISCOSITY),
+							.values = values,
+							.annotations = NULL
+						},
+						&viscosity,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	sscanf(viscosity, "%f", &drizzle_viscosity);
 
diff --git a/src/modules/flui2d/flui2d.c b/src/modules/flui2d/flui2d.c
index 5fb6087..ff0b6a4 100644
--- a/src/modules/flui2d/flui2d.c
+++ b/src/modules/flui2d/flui2d.c
@@ -283,7 +283,7 @@ static void flui2d_render_fragment(void *context, unsigned ticks, unsigned cpu,
 
 
 /* Settings hooks for configurable variables */
-static int flui2d_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int flui2d_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
 	const char	*viscosity;
 	const char	*diffusion;
@@ -307,61 +307,52 @@ static int flui2d_setup(const til_settings_t *settings, til_setting_desc_t **nex
 				".01",
 				NULL
 			};
-
-
-	viscosity = til_settings_get_value(settings, "viscosity");
-	if (!viscosity) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Fluid Viscosity",
-						.key = "viscosity",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(DEFAULT_VISCOSITY),
-						.values = values,
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	diffusion = til_settings_get_value(settings, "diffusion");
-	if (!diffusion) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Fluid Diffusion",
-						.key = "diffusion",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(DEFAULT_DIFFUSION),
-						.values = values,
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	decay = til_settings_get_value(settings, "decay");
-	if (!decay) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Fluid Decay",
-						.key = "decay",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(DEFAULT_DECAY),
-						.values = decay_values,
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Fluid Viscosity",
+							.key = "viscosity",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(DEFAULT_VISCOSITY),
+							.values = values,
+							.annotations = NULL
+						},
+						&viscosity,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Fluid Diffusion",
+							.key = "diffusion",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(DEFAULT_DIFFUSION),
+							.values = values,
+							.annotations = NULL
+						},
+						&diffusion,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Fluid Decay",
+							.key = "decay",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(DEFAULT_DECAY),
+							.values = decay_values,
+							.annotations = NULL
+						},
+						&decay,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	/* TODO: return -EINVAL on parse errors? */
 	sscanf(viscosity, "%f", &flui2d_viscosity);
diff --git a/src/modules/rtv/rtv.c b/src/modules/rtv/rtv.c
index a517e8c..91da0a5 100644
--- a/src/modules/rtv/rtv.c
+++ b/src/modules/rtv/rtv.c
@@ -48,7 +48,7 @@ static void * rtv_create_context(unsigned ticks, unsigned num_cpus);
 static void rtv_destroy_context(void *context);
 static void rtv_prepare_frame(void *context, unsigned ticks, unsigned n_cpus, til_fb_fragment_t *fragment, til_fragmenter_t *res_fragmenter);
 static void rtv_finish_frame(void *context, unsigned ticks, til_fb_fragment_t *fragment);
-static int rtv_setup(const til_settings_t *settings, til_setting_desc_t **next_setting);
+static int rtv_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc);
 
 static unsigned rtv_duration = RTV_DURATION_SECS;
 static unsigned rtv_context_duration = RTV_CONTEXT_DURATION_SECS;
@@ -94,9 +94,10 @@ static void randomize_channels(rtv_context_t *ctxt)
 
 static char * randomize_module_setup(const til_module_t *module)
 {
-	til_settings_t		*settings;
-	til_setting_desc_t	*desc;
-	char			*arg;
+	til_settings_t			*settings;
+	const til_setting_t		*setting;
+	const til_setting_desc_t	*desc;
+	char				*arg;
 
 	if (!module->setup)
 		return NULL;
@@ -105,12 +106,12 @@ static char * randomize_module_setup(const til_module_t *module)
 	if (!settings)
 		return NULL;
 
-	while (module->setup(settings, &desc) > 0) {
+	while (module->setup(settings, &setting, &desc) > 0) {
 		if (desc->random) {
 			char	*value;
 
 			value = desc->random();
-			til_settings_add_value(settings, desc->key, value);
+			til_settings_add_value(settings, desc->key, value, desc);
 			free(value);
 		} else if (desc->values) {
 			int	n;
@@ -119,12 +120,10 @@ static char * randomize_module_setup(const til_module_t *module)
 
 			n = rand() % n;
 
-			til_settings_add_value(settings, desc->key, desc->values[n]);
+			til_settings_add_value(settings, desc->key, desc->values[n], desc);
 		} else {
-			til_settings_add_value(settings, desc->key, desc->preferred);
+			til_settings_add_value(settings, desc->key, desc->preferred, desc);
 		}
-
-		til_setting_desc_free(desc);
 	}
 
 	arg = til_settings_as_arg(settings);
@@ -313,114 +312,97 @@ static void rtv_finish_frame(void *context, unsigned ticks, til_fb_fragment_t *f
 }
 
 
-static int rtv_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int rtv_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
+	const char	*channels;
 	const char	*duration;
 	const char	*context_duration;
 	const char	*caption_duration;
 	const char	*snow_duration;
-	const char	*channels;
 	const char	*snow_module;
-
-	channels = til_settings_get_value(settings, "channels");
-	if (!channels) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Colon-Separated List Of Channel Modules",
-						.key = "channels",
-						.preferred = "all",
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	duration = til_settings_get_value(settings, "duration");
-	if (!duration) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Channel Duration In Seconds",
-						.key = "duration",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(RTV_DURATION_SECS),
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	context_duration = til_settings_get_value(settings, "context_duration");
-	if (!context_duration) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Context Duration In Seconds",
-						.key = "context_duration",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(RTV_CONTEXT_DURATION_SECS),
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	caption_duration = til_settings_get_value(settings, "caption_duration");
-	if (!caption_duration) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Caption Duration In Seconds",
-						.key = "caption_duration",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(RTV_CAPTION_DURATION_SECS),
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	snow_duration = til_settings_get_value(settings, "snow_duration");
-	if (!snow_duration) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Snow On Channel Switch Duration In Seconds",
-						.key = "snow_duration",
-						.regex = "\\.[0-9]+",
-						.preferred = TIL_SETTINGS_STR(RTV_SNOW_DURATION_SECS),
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
-
-	snow_module = til_settings_get_value(settings, "snow_module");
-	if (!snow_module) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Module To Use For Snow (\"none\" To Blank)",
-						.key = "snow_module",
-						.preferred = "snow",
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Colon-Separated List Of Channel Modules",
+							.key = "channels",
+							.preferred = "all",
+							.annotations = NULL
+						},
+						&channels,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Channel Duration In Seconds",
+							.key = "duration",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(RTV_DURATION_SECS),
+							.annotations = NULL
+						},
+						&duration,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Context Duration In Seconds",
+							.key = "context_duration",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(RTV_CONTEXT_DURATION_SECS),
+							.annotations = NULL
+						},
+						&context_duration,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Caption Duration In Seconds",
+							.key = "caption_duration",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(RTV_CAPTION_DURATION_SECS),
+							.annotations = NULL
+						},
+						&caption_duration,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Snow On Channel Switch Duration In Seconds",
+							.key = "snow_duration",
+							.regex = "\\.[0-9]+",
+							.preferred = TIL_SETTINGS_STR(RTV_SNOW_DURATION_SECS),
+							.annotations = NULL
+						},
+						&snow_duration,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Module To Use For Snow (\"none\" To Blank)",
+							.key = "snow_module",
+							.preferred = "snow",
+							.annotations = NULL
+						},
+						&snow_module,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	/* turn channels colon-separated list into a null-terminated array of strings */
 	if (strcmp(channels, "all")) {
diff --git a/src/modules/sparkler/sparkler.c b/src/modules/sparkler/sparkler.c
index 8b8681f..6a4b604 100644
--- a/src/modules/sparkler/sparkler.c
+++ b/src/modules/sparkler/sparkler.c
@@ -96,83 +96,75 @@ static void sparkler_render_fragment(void *context, unsigned ticks, unsigned cpu
 
 
 /* Settings hooks for configurable variables */
-static int sparkler_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int sparkler_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
 	const char	*show_bsp_leafs;
 	const char	*show_bsp_matches;
 	const char	*values[] = {
-				"off",
-				"on",
-				NULL
+			       "off",
+			       "on",
+			       NULL
 			};
+	int		r;
 
 	/* TODO: return -EINVAL on parse errors? */
 
-	show_bsp_leafs = til_settings_get_value(settings, "show_bsp_leafs");
-	if (!show_bsp_leafs) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Show BSP Leaf Node Bounding Boxes",
-						.key = "show_bsp_leafs",
-						.preferred = "off",
-						.values = values,
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Show BSP Leaf Node Bounding Boxes",
+							.key = "show_bsp_leafs",
+							.preferred = "off",
+							.values = values
+						},
+						&show_bsp_leafs,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	if (!strcasecmp(show_bsp_leafs, "on")) {
+		const char	*depth_values[] = {
+					"0",
+					"4",
+					"6",
+					"8",
+					"10",
+					NULL
+				};
 		const char	*show_bsp_leafs_min_depth;
 
 		sparkler_conf.show_bsp_leafs = 1;
 
-		show_bsp_leafs_min_depth = til_settings_get_value(settings, "show_bsp_leafs_min_depth");
-		if (!show_bsp_leafs_min_depth) {
-			const char	*depth_values[] = {
-						"0",
-						"4",
-						"6",
-						"8",
-						"10",
-						NULL
-					};
-			int	r;
-
-			r = til_setting_desc_clone(&(til_setting_desc_t){
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
 							.name = "Show BSP Leaf Node Bounding Boxes Minimum Depth",
 							.key = "show_bsp_leafs_min_depth",
 							.preferred = "8",
-							.values = depth_values,
-						}, next_setting);
-			if (r < 0)
-				return r;
-
-			return 1;
-		}
+							.values = depth_values
+						},
+						&show_bsp_leafs_min_depth,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 		sscanf(show_bsp_leafs_min_depth, "%u", &sparkler_conf.show_bsp_leafs_min_depth);
 	} else {
 		sparkler_conf.show_bsp_leafs = 0;
 	}
 
-	show_bsp_matches = til_settings_get_value(settings, "show_bsp_matches");
-	if (!show_bsp_matches) {
-		int	r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Show BSP Search Matches",
-						.key = "show_bsp_matches",
-						.preferred = "off",
-						.values = values,
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Show BSP Search Matches",
+							.key = "show_bsp_matches",
+							.preferred = "off",
+							.values = values
+						},
+						&show_bsp_matches,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	if (!strcasecmp(show_bsp_matches, "on"))
 		sparkler_conf.show_bsp_matches = 1;
@@ -182,21 +174,18 @@ static int sparkler_setup(const til_settings_t *settings, til_setting_desc_t **n
 	if (!strcasecmp(show_bsp_matches, "on")) {
 		const char	*show_bsp_matches_affected_only;
 
-		show_bsp_matches_affected_only = til_settings_get_value(settings, "show_bsp_matches_affected_only");
-		if (!show_bsp_matches_affected_only) {
-			int	r;
-
-			r = til_setting_desc_clone(&(til_setting_desc_t){
-							.name = "Show Only Affected BSP Search Matches",
-							.key = "show_bsp_matches_affected_only",
-							.preferred = "off",
-							.values = values,
-						}, next_setting);
-			if (r < 0)
-				return r;
-
-			return 1;
-		}
+		r = til_settings_get_and_describe_value(settings,
+							&(til_setting_desc_t){
+								.name = "Show Only Affected BSP Search Matches",
+								.key = "show_bsp_matches_affected_only",
+								.preferred = "off",
+								.values = values
+							},
+							&show_bsp_matches_affected_only,
+							res_setting,
+							res_desc);
+		if (r)
+			return r;
 
 		if (!strcasecmp(show_bsp_matches_affected_only, "on"))
 			sparkler_conf.show_bsp_matches_affected_only = 1;
diff --git a/src/modules/stars/stars.c b/src/modules/stars/stars.c
index 9a0d2a9..c762043 100644
--- a/src/modules/stars/stars.c
+++ b/src/modules/stars/stars.c
@@ -201,10 +201,10 @@ static void stars_render_fragment(void *context, unsigned ticks, unsigned cpu, t
 	ctxt->offset_y = tmp_y;
 }
 
-int stars_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+int stars_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
 	const char	*rot_adj;
-	const char      *rot_adj_values[] = {
+	const char	*rot_adj_values[] = {
 				".0",
 				".00001",
 				".00003",
@@ -213,24 +213,22 @@ int stars_setup(const til_settings_t *settings, til_setting_desc_t **next_settin
 				".001",
 				NULL
 			};
+	int		r;
 
-	rot_adj = til_settings_get_value(settings, "rot_adj");
-	if(!rot_adj) {
-		int ret_val;
-
-		ret_val = til_setting_desc_clone(&(til_setting_desc_t){
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
 							.name = "Rotation Rate",
 							.key = "rot_adj",
 							.regex = "\\.[0-9]+",
 							.preferred = TIL_SETTINGS_STR(DEFAULT_ROT_ADJ),
 							.values = rot_adj_values,
 							.annotations = NULL
-						}, next_setting);
-		if(ret_val<0)
-			return ret_val;
-
-		return 1;
-	}
+						},
+						&rot_adj,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	sscanf(rot_adj, "%f", &stars_rot_adj);
 
diff --git a/src/modules/submit/submit.c b/src/modules/submit/submit.c
index 288a69a..d643a2c 100644
--- a/src/modules/submit/submit.c
+++ b/src/modules/submit/submit.c
@@ -322,32 +322,30 @@ static void submit_render_fragment(void *context, unsigned ticks, unsigned cpu,
 }
 
 
-static int submit_setup(const til_settings_t *settings, til_setting_desc_t **next_setting)
+static int submit_setup(const til_settings_t *settings, const til_setting_t **res_setting, const til_setting_desc_t **res_desc)
 {
+	const char	*values[] = {
+				"off",
+				"on",
+				NULL
+			};
 	const char	*bilerp;
-
-	bilerp = til_settings_get_value(settings, "bilerp");
-	if (!bilerp) {
-		const char	*values[] = {
-					"off",
-					"on",
-					NULL
-				};
-		int		r;
-
-		r = til_setting_desc_clone(&(til_setting_desc_t){
-						.name = "Bilinear Interpolation of Cell Colors",
-						.key = "bilerp",
-						.regex = NULL,
-						.preferred = values[0],
-						.values = values,
-						.annotations = NULL
-					}, next_setting);
-		if (r < 0)
-			return r;
-
-		return 1;
-	}
+	int		r;
+
+	r = til_settings_get_and_describe_value(settings,
+						&(til_setting_desc_t){
+							.name = "Bilinear Interpolation of Cell Colors",
+							.key = "bilerp",
+							.regex = NULL,
+							.preferred = values[0],
+							.values = values,
+							.annotations = NULL
+						},
+						&bilerp,
+						res_setting,
+						res_desc);
+	if (r)
+		return r;
 
 	if (!strcasecmp(bilerp, "on"))
 		bilerp_setting = 1;