modules/*: instantiate and use setups

Now modules allocate and return an opaque setup pointer in
res_setup when they implement a setup method.

Defaults are utilized when ${module}_create_context() receives a
NULL setup.  The default setup used in this case should match the
defaults/preferred values emitted by the module's setup method.
But performing setup should always be optional, so a NULL setup
provided to create_context() is to be expected.

No cleanup of these setup instances is currently performed, so
it's a small memory leak for now.  Since these are opaque and may
contain nested references to other allocations, simply using
free() somewhere in the frontend is insufficient.  There will
probably need to be something like a til_module_t.setup_free()
method added in the future which modules may assign libc's free()
to when appropriate, or their own more elaborate version.

Lifecycle for the settings is very simple; the setup method
returns an instance, the caller is expected to free it when no
longer needed (once free is implemented).  The create_context
consumer of a given setup must make its own copy of the settings
if necessary, and may not keep a reference - it must assume the
setup will be freed immediately after create_context() returns.
This enables the ability to reuse a setup instance across
multiple create_context() calls if desired, one can imagine
something like running the same module with the same settings
multiple times across multiple displays for instance.  If the
module has significant entropy the output will differ despite
being configured identically...

With this commit one may change settings for any of the modules
*while* the modules are actively rendering a given context, and
the settings should *not* be visible.  They should only affect
the context they're supplied to.

1 files changed, 49 insertions, 24 deletions

diff --git a/src/modules/sparkler/sparkler.c b/src/modules/sparkler/sparkler.c
index 51184b1..272c0fd 100644
--- a/src/modules/sparkler/sparkler.c
+++ b/src/modules/sparkler/sparkler.c
@@ -16,20 +16,31 @@
 
 #define INIT_PARTS 100
 
+typedef struct sparkler_setup_t {
+	unsigned		show_bsp_leafs:1;
+	unsigned		show_bsp_matches:1;
+	unsigned		show_bsp_matches_affected_only:1;
+	unsigned		show_bsp_leafs_min_depth;
+} sparkler_setup_t;
+
 typedef struct sparkler_context_t {
-	particles_t	*particles;
-	unsigned	n_cpus;
+	particles_t		*particles;
+	unsigned		n_cpus;
+	sparkler_setup_t	setup;
 } sparkler_context_t;
 
 extern particle_ops_t	simple_ops;
 
-static particles_conf_t	sparkler_conf;
+static sparkler_setup_t sparkler_default_setup;
 
 static void * sparkler_create_context(unsigned ticks, unsigned num_cpus, void *setup)
 {
 	static int		initialized;
 	sparkler_context_t	*ctxt;
 
+	if (!setup)
+		setup = &sparkler_default_setup;
+
 	if (!initialized) {
 		srand(time(NULL) + getpid());
 		initialized = 1;
@@ -39,7 +50,14 @@ static void * sparkler_create_context(unsigned ticks, unsigned num_cpus, void *s
 	if (!ctxt)
 		return NULL;
 
-	ctxt->particles = particles_new(&sparkler_conf);
+	ctxt->setup = *(sparkler_setup_t *)setup;
+
+	ctxt->particles = particles_new(&(particles_conf_t){
+						.show_bsp_leafs = ((sparkler_setup_t *)setup)->show_bsp_leafs,
+						.show_bsp_matches = ((sparkler_setup_t *)setup)->show_bsp_matches,
+						.show_bsp_leafs_min_depth = ((sparkler_setup_t *)setup)->show_bsp_leafs_min_depth,
+						.show_bsp_matches_affected_only = ((sparkler_setup_t *)setup)->show_bsp_matches_affected_only,
+					});
 	if (!ctxt->particles) {
 		free(ctxt);
 		return NULL;
@@ -74,7 +92,7 @@ static void sparkler_prepare_frame(void *context, unsigned ticks, unsigned ncpus
 	*res_fragmenter = sparkler_fragmenter;
 	ctxt->n_cpus = ncpus;
 
-	if (sparkler_conf.show_bsp_matches)
+	if (ctxt->setup.show_bsp_matches)
 		til_fb_fragment_zero(fragment);
 
 	particles_sim(ctxt->particles, fragment);
@@ -88,7 +106,7 @@ static void sparkler_render_fragment(void *context, unsigned ticks, unsigned cpu
 {
 	sparkler_context_t	*ctxt = context;
 
-	if (!sparkler_conf.show_bsp_matches)
+	if (!ctxt->setup.show_bsp_matches)
 		til_fb_fragment_zero(fragment);
 
 	particles_draw(ctxt->particles, fragment);
@@ -99,7 +117,9 @@ static void sparkler_render_fragment(void *context, unsigned ticks, unsigned cpu
 static int sparkler_setup(const til_settings_t *settings, til_setting_t **res_setting, const til_setting_desc_t **res_desc, void **res_setup)
 {
 	const char	*show_bsp_leafs;
+	const char	*show_bsp_leafs_min_depth;
 	const char	*show_bsp_matches;
+	const char	*show_bsp_matches_affected_only;
 	const char	*values[] = {
 			       "off",
 			       "on",
@@ -131,9 +151,6 @@ static int sparkler_setup(const til_settings_t *settings, til_setting_t **res_se
 					"10",
 					NULL
 				};
-		const char	*show_bsp_leafs_min_depth;
-
-		sparkler_conf.show_bsp_leafs = 1;
 
 		r = til_settings_get_and_describe_value(settings,
 							&(til_setting_desc_t){
@@ -147,10 +164,6 @@ static int sparkler_setup(const til_settings_t *settings, til_setting_t **res_se
 							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;
 	}
 
 	r = til_settings_get_and_describe_value(settings,
@@ -166,14 +179,7 @@ static int sparkler_setup(const til_settings_t *settings, til_setting_t **res_se
 	if (r)
 		return r;
 
-	if (!strcasecmp(show_bsp_matches, "on"))
-		sparkler_conf.show_bsp_matches = 1;
-	else
-		sparkler_conf.show_bsp_matches = 0;
-
 	if (!strcasecmp(show_bsp_matches, "on")) {
-		const char	*show_bsp_matches_affected_only;
-
 		r = til_settings_get_and_describe_value(settings,
 							&(til_setting_desc_t){
 								.name = "Show only narrow-phase affected match results",
@@ -187,10 +193,29 @@ static int sparkler_setup(const til_settings_t *settings, til_setting_t **res_se
 		if (r)
 			return r;
 
-		if (!strcasecmp(show_bsp_matches_affected_only, "on"))
-			sparkler_conf.show_bsp_matches_affected_only = 1;
-		else
-			sparkler_conf.show_bsp_matches_affected_only = 0;
+	}
+
+	if (res_setup) {
+		sparkler_setup_t	*setup;
+
+		setup = calloc(1, sizeof(*setup));
+		if (!setup)
+			return -ENOMEM;
+
+		if (!strcasecmp(show_bsp_leafs, "on")) {
+			setup->show_bsp_leafs = 1;
+
+			sscanf(show_bsp_leafs_min_depth, "%u", &setup->show_bsp_leafs_min_depth);
+		}
+
+		if (!strcasecmp(show_bsp_matches, "on")) {
+			setup->show_bsp_matches = 1;
+
+			if (!strcasecmp(show_bsp_matches_affected_only, "on"))
+				setup->show_bsp_matches_affected_only = 1;
+		}
+
+		*res_setup = setup;
 	}
 
 	return 0;