til: add til_get_module_names() helper

Composite modules that want to provide "all" aliases for modules
like rtv have to construct a comma-separated string of all module
names, usually filtered by some flags.

This helper does just that, but it does add yet another
open_memstream() user to revisit when those all get fixed up.

2 files changed, 31 insertions, 0 deletions

diff --git a/src/til.c b/src/til.c
index c680db8..ee42e68 100644
--- a/src/til.c
+++ b/src/til.c
@@ -4,6 +4,7 @@
 #include <fcntl.h>
 #include <inttypes.h>
 #include <pthread.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdint.h>
@@ -166,6 +167,35 @@ void til_get_modules(const til_module_t ***res_modules, size_t *res_n_modules)
 }
 
 
+char * til_get_module_names(unsigned flags_excluded)
+{
+	const til_module_t	**modules;
+	size_t			n_modules;
+	char			*buf;
+	size_t			bufsz;
+	FILE			*fp;
+
+	/* FIXME TODO: more unportable memstream! */
+	fp = open_memstream(&buf, &bufsz);
+	if (!fp)
+		return NULL;
+
+	til_get_modules(&modules, &n_modules);
+	for (size_t i = 0, j = 0; i < n_modules; i++) {
+		const til_module_t	*mod = modules[i];
+
+		if ((mod->flags & flags_excluded))
+			continue;
+
+		fprintf(fp, "%s%s", j ? "," : "", mod->name);
+		j++;
+	}
+	fclose(fp);
+
+	return buf;
+}
+
+
 static void module_render_fragment(til_module_context_t *context, til_stream_t *stream, til_threads_t *threads, unsigned ticks, til_fb_fragment_t **fragment_ptr)
 {
 	const til_module_t	*module;
diff --git a/src/til.h b/src/til.h
index 6388a32..0a0cd6d 100644
--- a/src/til.h
+++ b/src/til.h
@@ -42,6 +42,7 @@ void til_quiesce(void);
 void til_shutdown(void);
 const til_module_t * til_lookup_module(const char *name);
 void til_get_modules(const til_module_t ***res_modules, size_t *res_n_modules);
+char * til_get_module_names(unsigned flags_excluded);
 void til_module_render(til_module_context_t *context, til_stream_t *stream, unsigned ticks, til_fb_fragment_t **fragment_ptr);
 int til_module_create_context(const til_module_t *module, til_stream_t *stream, unsigned seed, unsigned ticks, unsigned n_cpus, til_setup_t *setup, til_module_context_t **res_context);
 til_module_context_t * til_module_destroy_context(til_module_context_t *context, til_stream_t *stream);