pulse-server: support latency_msec in module-raop-discover

See #3247

src/modules/module-protocol-pulse/modules/module-raop-discover.c

@@ -19,6 +19,8 @@ struct module_raop_discover_data {
 
 	struct spa_hook mod_listener;
 	struct pw_impl_module *mod;
+
+	uint32_t latency_msec;
 };
 
 static void module_destroy(void *data)
@@ -37,10 +39,25 @@ static const struct pw_impl_module_events module_events = {
 static int module_raop_discover_load(struct module *module)
 {
 	struct module_raop_discover_data *data = module->user_data;
+	FILE *f;
+	char *args;
+	size_t size;
+
+	if ((f = open_memstream(&args, &size)) == NULL)
+		return -errno;
+
+	fprintf(f, "{");
+	if (data->latency_msec > 0)
+		fprintf(f, " raop.latency.ms = %u ", data->latency_msec);
+	fprintf(f, "}");
+	fclose(f);
 
 	data->mod = pw_context_load_module(module->impl->context,
 			"libpipewire-module-raop-discover",
-			NULL, NULL);
+			args, NULL);
+
+	free(args);
+
 	if (data->mod == NULL)
 		return -errno;
 
@@ -75,9 +92,12 @@ static int module_raop_discover_prepare(struct module * const module)
 {
 	PW_LOG_TOPIC_INIT(mod_topic);
 
+	struct pw_properties * const props = module->props;
 	struct module_raop_discover_data * const data = module->user_data;
 	data->module = module;
 
+	pw_properties_fetch_uint32(props, "latency_msec", &data->latency_msec);
+
 	return 0;
 }
 

src/modules/module-raop-discover.c

@@ -41,6 +41,8 @@
  *
  * Options specific to the behavior of this module
  *
+ * - `raop.latency.ms` = latency for all streams in microseconds. This
+ *    can be overwritten in the stream rules.
  * - `stream.rules` = <rules>: match rules, use create-stream actions. See
  *   \ref page_module_raop_sink for module properties.
  *
@@ -50,6 +52,7 @@
  * context.modules = [
  * {   name = libpipewire-raop-discover
  *     args = {
+ *         #raop.latency.ms = 1000
  *         stream.rules = [
  *             {   matches = [
  *                     {    raop.ip = "~.*"
@@ -410,6 +413,9 @@ static void resolver_cb(AvahiServiceResolver *r, AvahiIfIndex interface, AvahiPr
 		avahi_free(value);
 	}
 
+	if ((str = pw_properties_get(impl->properties, "raop.latency.ms")) != NULL)
+		pw_properties_set(props, "raop.latency.ms", str);
+
 	if ((str = pw_properties_get(impl->properties, "stream.rules")) == NULL)
 		str = DEFAULT_CREATE_RULES;
 	if (str != NULL) {