metadata: store default-nodes as JSON

Don't just store the id in the metadata but a JSON object with
the node name. This makes it possible to easily introspect the
metadata and also extend the metadata with more fields later.

Instead of matching the metadata id to the global ids we now
have to match it against the name.

pipewire-alsa/alsa-plugins/ctl_pipewire.c

@@ -26,6 +26,7 @@
 #include <alsa/control_external.h>
 
 #include <spa/utils/result.h>
+#include <spa/utils/json.h>
 #include <spa/param/props.h>
 #include <spa/param/audio/format-utils.h>
 
@@ -62,11 +63,11 @@ typedef struct {
 	int pending_seq;
 	int error;
 
-	uint32_t sink;
+	char default_sink[1024];
 	int sink_muted;
 	struct volume sink_volume;
 
-	uint32_t source;
+	char default_source[1024];
 	int source_muted;
 	struct volume source_volume;
 
@@ -153,16 +154,25 @@ static int wait_resync(snd_ctl_pipewire_t *ctl)
 	return 0;
 }
 
-static struct global *find_global(snd_ctl_pipewire_t *ctl, uint32_t id, const char *type)
+static struct global *find_global(snd_ctl_pipewire_t *ctl, uint32_t id,
+		const char *name, const char *type)
 {
 	struct global *g;
+	uint32_t name_id = name ? (uint32_t)atoi(name) : SPA_ID_INVALID;
+	const char *str;
+
 	spa_list_for_each(g, &ctl->globals, link) {
-		if (g->id == id &&
+		if ((g->id == id || g->id == name_id) &&
 		    (type == NULL || strcmp(g->ginfo->type, type) == 0))
 			return g;
+		if (name != NULL && name[0] != '\0' &&
+		    (str = pw_properties_get(g->props, PW_KEY_NODE_NAME)) != NULL &&
+		    strcmp(name, str) == 0)
+			return g;
 	}
 	return NULL;
 }
+
 static struct global *find_best_node(snd_ctl_pipewire_t *ctl, uint32_t flags)
 {
 	struct global *g, *best = NULL;
@@ -202,13 +212,13 @@ static int pipewire_update_volume(snd_ctl_pipewire_t * ctl)
 	bool changed = false;
 	struct global *g;
 
-	if (ctl->sink == 0)
+	if (ctl->default_sink[0] == '\0')
 		g = find_best_node(ctl, NODE_FLAG_SINK);
 	else
-		g = find_global(ctl, ctl->sink, PW_TYPE_INTERFACE_Node);
+		g = find_global(ctl, SPA_ID_INVALID, ctl->default_sink,
+				PW_TYPE_INTERFACE_Node);
 
 	if (g) {
-		ctl->sink = g->id;
 		if (!!ctl->sink_muted != !!g->node.mute) {
 			ctl->sink_muted = g->node.mute;
 			ctl->updated |= UPDATE_SINK_MUTE;
@@ -221,13 +231,13 @@ static int pipewire_update_volume(snd_ctl_pipewire_t * ctl)
 		}
 	}
 
-	if (ctl->source == 0)
+	if (ctl->default_source[0] == '\0')
 		g = find_best_node(ctl, NODE_FLAG_SOURCE);
 	else
-		g = find_global(ctl, ctl->source, PW_TYPE_INTERFACE_Node);
+		g = find_global(ctl, SPA_ID_INVALID, ctl->default_source,
+				PW_TYPE_INTERFACE_Node);
 
 	if (g) {
-		ctl->source = g->id;
 		if (!!ctl->source_muted != !!g->node.mute) {
 			ctl->source_muted = g->node.mute;
 			ctl->updated |= UPDATE_SOURCE_MUTE;
@@ -270,9 +280,9 @@ static int pipewire_elem_count(snd_ctl_ext_t * ext)
 		goto finish;
 	}
 
-	if (ctl->source)
+	if (ctl->default_source[0] != '\0')
 		count += 2;
-	if (ctl->sink)
+	if (ctl->default_sink[0] != '\0')
 		count += 2;
 
 finish:
@@ -300,7 +310,7 @@ static int pipewire_elem_list(snd_ctl_ext_t * ext, unsigned int offset,
 	if (err < 0)
 		goto finish;
 
-	if (ctl->source) {
+	if (ctl->default_source[0] != '\0') {
 		if (offset == 0)
 			snd_ctl_elem_id_set_name(id, SOURCE_VOL_NAME);
 		else if (offset == 1)
@@ -479,7 +489,7 @@ static struct spa_pod *build_volume_mute(struct spa_pod_builder *b, struct volum
 	return spa_pod_builder_pop(b, &f[0]);
 }
 
-static int set_volume_mute(snd_ctl_pipewire_t *ctl, uint32_t node, struct volume *volume, int *mute)
+static int set_volume_mute(snd_ctl_pipewire_t *ctl, const char *name, struct volume *volume, int *mute)
 {
 	struct global *g, *dg;
 	uint32_t id = SPA_ID_INVALID, device_id = SPA_ID_INVALID;
@@ -488,12 +498,12 @@ static int set_volume_mute(snd_ctl_pipewire_t *ctl, uint32_t node, struct volume
 	struct spa_pod_frame f[2];
 	struct spa_pod *param;
 
-	g = find_global(ctl, node, PW_TYPE_INTERFACE_Node);
+	g = find_global(ctl, SPA_ID_INVALID, name, PW_TYPE_INTERFACE_Node);
 	if (g == NULL)
 		return -EINVAL;
 
 	if (SPA_FLAG_IS_SET(g->node.flags, NODE_FLAG_DEVICE_VOLUME) &&
-	    (dg = find_global(ctl, g->node.device_id, PW_TYPE_INTERFACE_Device)) != NULL) {
+	    (dg = find_global(ctl, g->node.device_id, NULL, PW_TYPE_INTERFACE_Device)) != NULL) {
 		if (g->node.flags & NODE_FLAG_SINK)
 			id = dg->device.active_route_output;
 		else if (g->node.flags & NODE_FLAG_SOURCE)
@@ -589,14 +599,14 @@ static int pipewire_write_integer(snd_ctl_ext_t * ext, snd_ctl_ext_key_t key,
 			vol->values[i] = value[i];
 
 		if (key == 0)
-			set_volume_mute(ctl, ctl->source, vol, NULL);
+			set_volume_mute(ctl, ctl->default_source, vol, NULL);
 		else
-			set_volume_mute(ctl, ctl->sink, vol, NULL);
+			set_volume_mute(ctl, ctl->default_sink, vol, NULL);
 	} else {
 		if (key == 1)
-			set_volume_mute(ctl, ctl->source, NULL, &ctl->source_muted);
+			set_volume_mute(ctl, ctl->default_source, NULL, &ctl->source_muted);
 		else
-			set_volume_mute(ctl, ctl->sink, NULL, &ctl->sink_muted);
+			set_volume_mute(ctl, ctl->default_sink, NULL, &ctl->sink_muted);
 	}
 
 	wait_resync(ctl);
@@ -651,7 +661,7 @@ static int pipewire_read_event(snd_ctl_ext_t * ext, snd_ctl_elem_id_t * id,
 		goto finish;
 	}
 
-	if (ctl->source)
+	if (ctl->default_source[0] != '\0')
 		offset = 2;
 	else
 		offset = 0;
@@ -968,6 +978,29 @@ struct global_info node_info = {
 };
 
 /** metadata */
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
+{
+	struct spa_json it[2];
+	const char *v;
+	char k[128];
+
+	spa_json_init(&it[0], obj, strlen(obj));
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
+
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
+		if (strcmp(k, key) == 0) {
+			if (spa_json_get_string(&it[1], value, len) <= 0)
+				continue;
+			return 0;
+		} else {
+			if (spa_json_next(&it[1], &v) <= 0)
+				break;
+		}
+	}
+	return -ENOENT;
+}
+
 static int metadata_property(void *object,
                         uint32_t subject,
                         const char *key,
@@ -978,11 +1011,20 @@ static int metadata_property(void *object,
 	snd_ctl_pipewire_t *ctl = g->ctl;
 
 	if (subject == PW_ID_CORE) {
-		uint32_t val = (key && value) ? (uint32_t)atoi(value) : 0;
+		if (key == NULL || strcmp(key, "default.audio.sink") == 0) {
-		if (key == NULL || strcmp(key, "default.audio.sink") == 0)
+			if (value == NULL ||
-			ctl->sink = val;
+			    json_object_find(value, "name",
-		if (key == NULL || strcmp(key, "default.audio.source") == 0)
+					ctl->default_sink, sizeof(ctl->default_sink)) < 0)
-			ctl->source = val;
+				ctl->default_sink[0] = '\0';
+			pw_log_debug("found default sink: %s", ctl->default_sink);
+		}
+		if (key == NULL || strcmp(key, "default.audio.source") == 0) {
+			if (value == NULL ||
+			    json_object_find(value, "name",
+					ctl->default_source, sizeof(ctl->default_source)) < 0)
+				ctl->default_source[0] = '\0';
+			pw_log_debug("found default source: %s", ctl->default_source);
+		}
         }
         return 0;
 }
@@ -1094,10 +1136,18 @@ static void registry_event_global(void *data, uint32_t id,
 static void registry_event_global_remove(void *data, uint32_t id)
 {
 	snd_ctl_pipewire_t *ctl = data;
-	if (ctl->sink == id)
+	struct global *g;
-		ctl->sink = 0;
+	const char *name;
-	if (ctl->source == id)
+
-		ctl->source = 0;
+	if ((g = find_global(ctl, id, NULL, PW_TYPE_INTERFACE_Node)) == NULL)
+		return;
+	if ((name = pw_properties_get(g->props, PW_KEY_NODE_NAME)) == NULL)
+		return;
+
+	if (strcmp(name, ctl->default_sink) == 0)
+		ctl->default_sink[0] = '\0';
+	if (strcmp(name, ctl->default_source) == 0)
+		ctl->default_source[0] = '\0';
 }
 
 static const struct pw_registry_events registry_events = {
@@ -1229,25 +1279,16 @@ SND_CTL_PLUGIN_DEFINE_FUNC(pipewire)
 
 	spa_list_init(&ctl->globals);
 
-	if (source)
+	if (source == NULL)
-		ctl->source = atoi(source);
+		source = device;
-	else if (device)
+	if (source != NULL)
-		ctl->source = atoi(device);
+		snprintf(ctl->default_source, sizeof(ctl->default_source),
-
+				"%s", source);
-	if ((source || device) && !ctl->source) {
+	if (sink == NULL)
-		err = -EINVAL;
+		sink = device;
-		goto error;
+	if (sink != NULL)
-	}
+		snprintf(ctl->default_sink, sizeof(ctl->default_sink),
-
+				"%s", sink);
-	if (sink)
-		ctl->sink = atoi(sink);
-	else if (device)
-		ctl->sink = atoi(device);
-
-	if ((sink || device) && !ctl->sink) {
-		err = -EINVAL;
-		goto error;
-	}
 
 	ctl->mainloop = pw_thread_loop_new("alsa-pipewire", NULL);
 	if (ctl->mainloop == NULL) {

pipewire-jack/src/pipewire-jack.c

@@ -44,6 +44,7 @@
 #include <spa/param/video/format-utils.h>
 #include <spa/debug/types.h>
 #include <spa/debug/pod.h>
+#include <spa/utils/json.h>
 
 #include <pipewire/pipewire.h>
 #include <pipewire/private.h>
@@ -110,6 +111,7 @@ struct object {
 	union {
 		struct {
 			char name[JACK_CLIENT_NAME_SIZE+1];
+			char node_name[512];
 			int32_t priority;
 			uint32_t client_id;
 		} node;
@@ -132,6 +134,7 @@ struct object {
 			int32_t priority;
 			struct port *port;
 			bool is_monitor;
+			struct object *node;
 		} port;
 	};
 };
@@ -241,8 +244,8 @@ struct metadata {
 	struct pw_metadata *proxy;
 	struct spa_hook listener;
 
-	uint32_t default_audio_sink;
+	char default_audio_sink[1024];
-	uint32_t default_audio_source;
+	char default_audio_source[1024];
 };
 
 struct client {
@@ -548,6 +551,21 @@ static struct object *find_node(struct client *c, const char *name)
 	return NULL;
 }
 
+static bool is_port_default(struct client *c, struct object *o)
+{
+	struct object *ot;
+
+	if (c->metadata == NULL)
+		return false;
+
+	if ((ot = o->port.node) != NULL &&
+	    (strcmp(ot->node.node_name, c->metadata->default_audio_source) == 0 ||
+	     strcmp(ot->node.node_name, c->metadata->default_audio_sink) == 0))
+		return true;
+
+	return false;
+}
+
 static struct object *find_port(struct client *c, const char *name)
 {
 	struct object *o;
@@ -557,10 +575,7 @@ static struct object *find_port(struct client *c, const char *name)
 		    strcmp(o->port.alias1, name) == 0 ||
 		    strcmp(o->port.alias2, name) == 0)
 			return o;
-		if (c->metadata &&
+		if (is_port_default(c, o) && strcmp(o->port.system, name) == 0)
-		    (o->port.node_id == c->metadata->default_audio_source ||
-		     o->port.node_id == c->metadata->default_audio_sink) &&
-		    strcmp(o->port.system, name) == 0)
 			return o;
 	}
 	return NULL;
@@ -2037,6 +2052,29 @@ static jack_uuid_t client_make_uuid(uint32_t id)
 	return uuid;
 }
 
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
+{
+	struct spa_json it[2];
+	const char *v;
+	char k[128];
+
+	spa_json_init(&it[0], obj, strlen(obj));
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
+
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
+		if (strcmp(k, key) == 0) {
+			if (spa_json_get_string(&it[1], value, len) <= 0)
+				continue;
+			return 0;
+		} else {
+			if (spa_json_next(&it[1], &v) <= 0)
+				break;
+		}
+	}
+	return -ENOENT;
+}
+
 static int metadata_property(void *object, uint32_t id,
 		const char *key, const char *type, const char *value)
 {
@@ -2047,11 +2085,26 @@ static int metadata_property(void *object, uint32_t id,
 	pw_log_info("set id:%u key:'%s' value:'%s' type:'%s'", id, key, value, type);
 
 	if (id == PW_ID_CORE) {
-		uint32_t val = (key && value) ? (uint32_t)atoi(value) : SPA_ID_INVALID;
+		if (key == NULL || strcmp(key, "default.audio.sink") == 0) {
-		if (key == NULL || strcmp(key, "default.audio.sink") == 0)
+			if (value != NULL) {
-			c->metadata->default_audio_sink = val;
+				if (json_object_find(value, "name",
-		if (key == NULL || strcmp(key, "default.audio.source") == 0)
+						c->metadata->default_audio_sink,
-			c->metadata->default_audio_source = val;
+						sizeof(c->metadata->default_audio_sink)) < 0)
+					value = NULL;
+			}
+			if (value == NULL)
+				c->metadata->default_audio_sink[0] = '\0';
+		}
+		if (key == NULL || strcmp(key, "default.audio.source") == 0) {
+			if (value != NULL) {
+				if (json_object_find(value, "name",
+						c->metadata->default_audio_source,
+						sizeof(c->metadata->default_audio_source)) < 0)
+					value = NULL;
+			}
+			if (value == NULL)
+				c->metadata->default_audio_source[0] = '\0';
+		}
 	} else {
 		pthread_mutex_lock(&c->context.lock);
 		o = pw_map_lookup(&c->context.globals, id);
@@ -2122,6 +2175,8 @@ static void registry_event_global(void *data, uint32_t id,
 			if (node_name != NULL)
 				snprintf(c->name, sizeof(c->name), "%s", node_name);
 		}
+		snprintf(o->node.node_name, sizeof(o->node.node_name),
+				"%s", node_name);
 
 		app = spa_dict_lookup(props, PW_KEY_APP_NAME);
 
@@ -2245,6 +2300,7 @@ static void registry_event_global(void *data, uint32_t id,
 
 			o->port.port_id = SPA_ID_INVALID;
 			o->port.priority = ot->node.priority;
+			o->port.node = ot;
 		}
 
 		if ((str = spa_dict_lookup(props, PW_KEY_OBJECT_PATH)) != NULL)
@@ -2303,8 +2359,8 @@ static void registry_event_global(void *data, uint32_t id,
 
 		c->metadata = pw_proxy_get_user_data(proxy);
 		c->metadata->proxy = (struct pw_metadata*)proxy;
-		c->metadata->default_audio_sink = SPA_ID_INVALID;
+		c->metadata->default_audio_sink[0] = '\0';
-		c->metadata->default_audio_source = SPA_ID_INVALID;
+		c->metadata->default_audio_source[0] = '\0';
 
 		pw_metadata_add_listener(proxy,
 				&c->metadata->listener,
@@ -2359,13 +2415,6 @@ static void registry_event_global_remove(void *object, uint32_t id)
 
 	pw_log_debug(NAME" %p: removed: %u", c, id);
 
-	if (c->metadata) {
-		if (id == c->metadata->default_audio_sink)
-			c->metadata->default_audio_sink = SPA_ID_INVALID;
-		if (id == c->metadata->default_audio_source)
-			c->metadata->default_audio_source = SPA_ID_INVALID;
-	}
-
 	pthread_mutex_lock(&c->context.lock);
 	o = pw_map_lookup(&c->context.globals, id);
 	pthread_mutex_unlock(&c->context.lock);
@@ -2376,6 +2425,12 @@ static void registry_event_global_remove(void *object, uint32_t id)
 
 	switch (o->type) {
 	case INTERFACE_Node:
+		if (c->metadata) {
+			if (strcmp(o->node.node_name, c->metadata->default_audio_sink) == 0)
+				c->metadata->default_audio_sink[0] = '\0';
+			if (strcmp(o->node.node_name, c->metadata->default_audio_source) == 0)
+				c->metadata->default_audio_source[0] = '\0';
+		}
 		if (c->registration_callback)
 			c->registration_callback(o->node.name, 0, c->registration_arg);
 		break;
@@ -4255,15 +4310,24 @@ static int port_compare_func(const void *v1, const void *v2)
 		!(*o2)->port.is_monitor;
 
 	if (c->metadata) {
+		struct object *ot1, *ot2;
+
+		ot1 = (*o1)->port.node;
+
 		if (is_cap1)
-			is_def1 = (*o1)->port.node_id == c->metadata->default_audio_source;
+			is_def1 = ot1 != NULL && strcmp(ot1->node.node_name,
+					c->metadata->default_audio_source) == 0;
 		else if (!is_cap1)
-			is_def1 = (*o1)->port.node_id == c->metadata->default_audio_sink;
+			is_def1 = ot1 != NULL && strcmp(ot1->node.node_name,
+					c->metadata->default_audio_sink) == 0;
+		ot2 = (*o2)->port.node;
 
 		if (is_cap2)
-			is_def2 = (*o2)->port.node_id == c->metadata->default_audio_source;
+			is_def2 = ot2 != NULL && strcmp(ot2->node.node_name,
+					c->metadata->default_audio_source) == 0;
 		else if (!is_cap2)
-			is_def2 = (*o2)->port.node_id == c->metadata->default_audio_sink;
+			is_def2 = ot2 != NULL && strcmp(ot2->node.node_name,
+					c->metadata->default_audio_sink) == 0;
 	}
 	if ((*o1)->port.type_id != (*o2)->port.type_id)
 		res = (*o1)->port.type_id - (*o2)->port.type_id;

src/examples/media-session/default-nodes.c

@@ -71,8 +71,20 @@ struct impl {
 	struct default_node defaults[4];
 
 	struct pw_properties *properties;
+
+	unsigned int sync:1;
 };
 
+static struct default_node *find_default(struct impl *impl, const char *key)
+{
+	struct default_node *def;
+	/* Check that the item key is a valid default key */
+	for (def = impl->defaults; def->key != NULL; ++def)
+		if (strcmp(key, def->key) == 0)
+			return def;
+	return NULL;
+}
+
 struct find_data {
 	struct impl *impl;
 	const char *name;
@@ -94,32 +106,34 @@ static int find_name(void *data, struct sm_object *object)
 	return 0;
 }
 
-#if 0
 static uint32_t find_id_for_name(struct impl *impl, const char *name)
 {
 	struct find_data d = { impl, name, SPA_ID_INVALID };
 	sm_media_session_for_each_object(impl->session, find_name, &d);
 	return d.id;
 }
-#endif
 
-static const char *find_name_for_id(struct impl *impl, uint32_t id)
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
 {
-	struct sm_object *obj;
+	struct spa_json it[2];
-	const char *str;
+	const char *v;
+	char k[128];
 
-	if (id == SPA_ID_INVALID)
+	spa_json_init(&it[0], obj, strlen(obj));
-		return NULL;
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
 
-	obj = sm_media_session_find_object(impl->session, id);
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
-	if (obj == NULL)
+		if (strcmp(k, key) == 0) {
-		return NULL;
+			if (spa_json_get_string(&it[1], value, len) <= 0)
-
+				continue;
-	if (strcmp(obj->type, PW_TYPE_INTERFACE_Node) == 0 &&
+			return 0;
-	    obj->props &&
+		} else {
-	    (str = pw_properties_get(obj->props, PW_KEY_NODE_NAME)) != NULL)
+			if (spa_json_next(&it[1], &v) <= 0)
-		return str;
+				break;
-	return NULL;
+		}
+	}
+	return -ENOENT;
 }
 
 static void remove_idle_timeout(struct impl *impl)
@@ -160,27 +174,41 @@ static int metadata_property(void *object, uint32_t subject,
 		const char *key, const char *type, const char *value)
 {
 	struct impl *impl = object;
-	uint32_t val;
+	int changed = 0;
-	bool changed = false;
+
+	if (impl->sync)
+		return 0;
 
 	if (subject == PW_ID_CORE) {
-		struct default_node *def;
+		if (key == NULL) {
-		val = (key && value) ? (uint32_t)atoi(value) : SPA_ID_INVALID;
+			pw_properties_clear(impl->properties);
-		for (def = impl->defaults; def->key != NULL; ++def) {
+			changed++;
-			if (key == NULL || strcmp(key, def->key) == 0) {
+		} else {
-				changed = (def->value != val);
+			uint32_t id;
-				def->value = val;
+			struct default_node *def;
+			char name[1024];
+
+			if ((def = find_default(impl, key)) == NULL)
+				return 0;
+
+			if (value == NULL) {
+				def->value = SPA_ID_INVALID;
+			} else {
+				if (json_object_find(value, "name", name, sizeof(name)) < 0)
+					return 0;
+
+				if ((id = find_id_for_name(impl, name)) == SPA_ID_INVALID)
+					return 0;
+
+				def->value = id;
+				changed += pw_properties_set(impl->properties,
+							key, value);
 			}
 		}
 	}
-	if (changed) {
+	if (changed)
-		const char *name = find_name_for_id(impl, val);
-		if (key == NULL)
-			pw_properties_clear(impl->properties);
-		else
-			pw_properties_setf(impl->properties, key, "{ \"name\": \"%s\" }", name);
 		add_idle_timeout(impl);
-	}
+
 	return 0;
 }
 
@@ -198,42 +226,22 @@ static void session_create(void *data, struct sm_object *object)
 		return;
 
 	spa_dict_for_each(item, &impl->properties->dict) {
-		struct spa_json it[2];
+		char name [1024] = "\0";
-		const char *value;
-		char name [1024] = "\0", key[128];
 		struct find_data d;
 
-		spa_json_init(&it[0], item->value, strlen(item->value));
+		if (find_default(impl, item->key) == NULL)
-		if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+			continue;
+
+		if (json_object_find(item->value, "name", name, sizeof(name)) < 0)
 			continue;
 
-		while (spa_json_get_string(&it[1], key, sizeof(key)-1) > 0) {
-			if (strcmp(key, "name") == 0) {
-				if (spa_json_get_string(&it[1], name, sizeof(name)) <= 0)
-					continue;
-			} else {
-				if (spa_json_next(&it[1], &value) <= 0)
-					break;
-			}
-		}
 		d = (struct find_data){ impl, name, SPA_ID_INVALID };
 		if (find_name(&d, object)) {
-			const struct default_node *def;
-
-			/* Check that the item key is a valid default key */
-			for (def = impl->defaults; def->key != NULL; ++def)
-				if (item->key != NULL && strcmp(item->key, def->key) == 0)
-					break;
-			if (def->key == NULL)
-				continue;
-
 			if (impl->session->metadata != NULL) {
-				char val[16];
+				pw_log_info("found %s with id:%u restore as %s",
-				snprintf(val, sizeof(val), "%u", d.id);
+						name, d.id, item->key);
-				pw_log_info("found %s with id:%s restore as %s",
-						name, val, item->key);
 				pw_metadata_set_property(impl->session->metadata,
-					PW_ID_CORE, item->key, SPA_TYPE_INFO_BASE"Id", val);
+					PW_ID_CORE, item->key, "Spa:String:JSON", item->value);
 			}
 		}
 	}
@@ -288,10 +296,10 @@ int sm_default_nodes_start(struct sm_media_session *session)
 	impl->session = session;
 	impl->context = session->context;
 
-	impl->defaults[0] = (struct default_node){ DEFAULT_CONFIG_AUDIO_SINK_KEY, SPA_ID_INVALID };
+	impl->defaults[0] = (struct default_node){ DEFAULT_CONFIG_AUDIO_SINK_KEY, };
-	impl->defaults[1] = (struct default_node){ DEFAULT_CONFIG_AUDIO_SOURCE_KEY, SPA_ID_INVALID };
+	impl->defaults[1] = (struct default_node){ DEFAULT_CONFIG_AUDIO_SOURCE_KEY, };
-	impl->defaults[2] = (struct default_node){ DEFAULT_CONFIG_VIDEO_SOURCE_KEY, SPA_ID_INVALID };
+	impl->defaults[2] = (struct default_node){ DEFAULT_CONFIG_VIDEO_SOURCE_KEY, };
-	impl->defaults[3] = (struct default_node){ NULL, SPA_ID_INVALID };
+	impl->defaults[3] = (struct default_node){ NULL, };
 
 	impl->properties = pw_properties_new(NULL, NULL);
 	if (impl->properties == NULL) {

src/examples/media-session/policy-node.c

@@ -35,6 +35,7 @@
 #include <spa/param/audio/format-utils.h>
 #include <spa/param/props.h>
 #include <spa/debug/pod.h>
+#include <spa/utils/json.h>
 
 #include "pipewire/pipewire.h"
 #include "extensions/metadata.h"
@@ -60,8 +61,8 @@
 struct default_node {
 	char *key;
 	char *key_config;
-	uint32_t value;
+	char *value;
-	uint32_t config;
+	char *config;
 };
 
 struct impl {
@@ -362,11 +363,56 @@ static void destroy_node(struct impl *impl, struct node *node)
 	sm_object_remove_data((struct sm_object*)node->obj, SESSION_KEY);
 }
 
-static struct node *find_node_by_id(struct impl *impl, uint32_t id)
+static inline int strzcmp(const char *s1, const char *s2)
+{
+	if (s1 == s2)
+		return 0;
+	if (s1 == NULL || s2 == NULL)
+		return 1;
+	return strcmp(s1, s2);
+}
+
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
+{
+	struct spa_json it[2];
+	const char *v;
+	char k[128];
+
+	spa_json_init(&it[0], obj, strlen(obj));
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
+
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
+		if (strcmp(k, key) == 0) {
+			if (spa_json_get_string(&it[1], value, len) <= 0)
+				continue;
+			return 0;
+		} else {
+			if (spa_json_next(&it[1], &v) <= 0)
+				break;
+		}
+	}
+	return -ENOENT;
+}
+
+static bool check_node_name(struct node *node, const char *name)
+{
+	const char *str;
+	if ((str = pw_properties_get(node->obj->obj.props, PW_KEY_NODE_NAME)) != NULL &&
+	    name != NULL && strcmp(str, name) == 0)
+		return true;
+	return false;
+}
+
+static struct node *find_node_by_id_name(struct impl *impl, uint32_t id, const char *name)
 {
 	struct node *node;
+	uint32_t name_id = name ? atoi(name) : SPA_ID_INVALID;
+
 	spa_list_for_each(node, &impl->node_list, link) {
-		if (node->id == id)
+		if (node->id == id || node->id == name_id)
+			return node;
+		if (check_node_name(node, name))
 			return node;
 	}
 	return NULL;
@@ -417,7 +463,6 @@ static void session_create(void *data, struct sm_object *object)
 
 static void session_remove(void *data, struct sm_object *object)
 {
-	struct default_node *def;
 	struct impl *impl = data;
 	pw_log_debug(NAME " %p: remove global '%d'", impl, object->id);
 
@@ -431,12 +476,7 @@ static void session_remove(void *data, struct sm_object *object)
 			if (n->peer == node)
 				n->peer = NULL;
 		}
-
-		for (def = impl->defaults; def->key != NULL; ++def)
-			if (def->config == object->id)
-				def->config = SPA_ID_INVALID;
 	}
-
 	sm_media_session_schedule_rescan(impl->session);
 }
 
@@ -491,14 +531,18 @@ static int find_node(void *data, struct node *node)
 
 	if (node->media) {
 		bool is_default = false;
+
 		if (strcmp(node->media, "Audio") == 0) {
 			if (node->direction == PW_DIRECTION_INPUT)
-				is_default = impl->defaults[DEFAULT_AUDIO_SINK].config == node->id;
+				is_default = check_node_name(node,
+						impl->defaults[DEFAULT_AUDIO_SINK].config);
 			else if (node->direction == PW_DIRECTION_OUTPUT)
-				is_default = impl->defaults[DEFAULT_AUDIO_SOURCE].config == node->id;
+				is_default = check_node_name(node,
+						impl->defaults[DEFAULT_AUDIO_SOURCE].config);
 		} else if (strcmp(node->media, "Video") == 0) {
 			if (node->direction == PW_DIRECTION_OUTPUT)
-				is_default = impl->defaults[DEFAULT_VIDEO_SOURCE].config == node->id;
+				is_default = check_node_name(node,
+						impl->defaults[DEFAULT_VIDEO_SOURCE].config);
 		}
 		if (is_default)
 			priority += 10000;
@@ -813,19 +857,30 @@ static void refresh_auto_default_nodes(struct impl *impl)
 	if (impl->session->metadata == NULL)
 		return;
 
+	pw_log_debug(NAME" %p: refresh", impl);
+
 	/* Auto set default nodes */
 	for (def = impl->defaults; def->key != NULL; ++def) {
 		struct node *node;
 		node = find_auto_default_node(impl, def);
-		if (node == NULL && def->value != SPA_ID_INVALID) {
+		if (node == NULL && def->value != NULL) {
-			def->value = SPA_ID_INVALID;
+			def->value = NULL;
-			pw_metadata_set_property(impl->session->metadata, PW_ID_CORE, def->key, NULL, NULL);
+			pw_metadata_set_property(impl->session->metadata,
-		} else if (node != NULL && def->value != node->id) {
+					PW_ID_CORE, def->key, NULL, NULL);
-			char buf[64];
+		} else if (node != NULL) {
-			def->value = node->id;
+			const char *name = pw_properties_get(node->obj->obj.props, PW_KEY_NODE_NAME);
-			snprintf(buf, sizeof(buf), "%d", node->id);
+			char buf[1024];
-			pw_metadata_set_property(impl->session->metadata, PW_ID_CORE, def->key,
+
-			                         SPA_TYPE_INFO_BASE"Id", buf);
+			if (strzcmp(name, def->value) == 0)
+				continue;
+
+			free(def->value);
+			def->value = strdup(name);
+
+			snprintf(buf, sizeof(buf), "{ \"name\": \"%s\" }", name);
+			pw_metadata_set_property(impl->session->metadata,
+					PW_ID_CORE, def->key,
+					"Spa:String:JSON", buf);
 		}
 	}
 }
@@ -905,21 +960,32 @@ static int metadata_property(void *object, uint32_t subject,
 		const char *key, const char *type, const char *value)
 {
 	struct impl *impl = object;
-	uint32_t val = (key && value) ? (uint32_t)atoi(value) : SPA_ID_INVALID;
 
 	if (subject == PW_ID_CORE) {
 		struct default_node *def;
 		bool changed = false;
+		char *val = NULL;
 
+		if (key != NULL && value != NULL) {
+			char name[1024];
+
+			pw_log_info("meta %s: %s", key, value);
+			if (json_object_find(value, "name", name, sizeof(name)) < 0)
+				return 0;
+			pw_log_info("meta name: %s", name);
+			val = name;
+		}
 		for (def = impl->defaults; def->key != NULL; ++def) {
 			if (key == NULL || strcmp(key, def->key_config) == 0) {
-				if (def->config != val)
+				if (strzcmp(def->config, val) != 0)
 					changed = true;
-				def->config = val;
+				free(def->config);
+				def->config = val ? strdup(val) : NULL;
 			}
 			if (key == NULL || strcmp(key, def->key) == 0) {
-				bool eff_changed = (def->value != val);
+				bool eff_changed = strzcmp(def->value, val) != 0;
-				def->value = val;
+				free(def->value);
+				def->value = val ? strdup(val) : NULL;
 
 				/* The effective value was changed. In case it was changed by
 				 * someone else than us, reset the value to avoid confusion. */
@@ -927,23 +993,21 @@ static int metadata_property(void *object, uint32_t subject,
 					refresh_auto_default_nodes(impl);
 			}
 		}
-
 		if (changed)
 			sm_media_session_schedule_rescan(impl->session);
-	} else {
+	} else if (key != NULL && strcmp(key, "target.node") == 0) {
-		if (val != SPA_ID_INVALID && strcmp(key, "target.node") == 0) {
+		if (value != NULL) {
 			struct node *src_node, *dst_node;
 
-			dst_node = find_node_by_id(impl, val);
+			dst_node = find_node_by_id_name(impl, SPA_ID_INVALID, value);
-			src_node = dst_node ? find_node_by_id(impl, subject) : NULL;
+			src_node = dst_node ? find_node_by_id_name(impl, subject, NULL) : NULL;
 
 			if (dst_node && src_node)
 				handle_move(impl, src_node, dst_node);
-		} else if (val == SPA_ID_INVALID && key != NULL &&
+		} else {
-				strcmp(key, "target.node") == 0) {
 			/* Unset target node. Schedule rescan to re-link, if needed. */
 			struct node *src_node;
-			src_node = find_node_by_id(impl, subject);
+			src_node = find_node_by_id_name(impl, subject, NULL);
 			if (src_node) {
 				free(src_node->obj->target_node);
 				src_node->obj->target_node = NULL;
@@ -974,15 +1038,15 @@ int sm_policy_node_start(struct sm_media_session *session)
 	impl->sample_rate = 48000;
 
 	impl->defaults[DEFAULT_AUDIO_SINK] = (struct default_node){
-		DEFAULT_AUDIO_SINK_KEY, DEFAULT_CONFIG_AUDIO_SINK_KEY, SPA_ID_INVALID, SPA_ID_INVALID
+		DEFAULT_AUDIO_SINK_KEY, DEFAULT_CONFIG_AUDIO_SINK_KEY, NULL, NULL
 	};
 	impl->defaults[DEFAULT_AUDIO_SOURCE] = (struct default_node){
-		DEFAULT_AUDIO_SOURCE_KEY, DEFAULT_CONFIG_AUDIO_SOURCE_KEY, SPA_ID_INVALID, SPA_ID_INVALID
+		DEFAULT_AUDIO_SOURCE_KEY, DEFAULT_CONFIG_AUDIO_SOURCE_KEY, NULL, NULL
 	};
 	impl->defaults[DEFAULT_VIDEO_SOURCE] = (struct default_node){
-		DEFAULT_VIDEO_SOURCE_KEY, DEFAULT_CONFIG_VIDEO_SOURCE_KEY, SPA_ID_INVALID, SPA_ID_INVALID
+		DEFAULT_VIDEO_SOURCE_KEY, DEFAULT_CONFIG_VIDEO_SOURCE_KEY, NULL, NULL
 	};
-	impl->defaults[3] = (struct default_node){ NULL, NULL, SPA_ID_INVALID, SPA_ID_INVALID };
+	impl->defaults[3] = (struct default_node){ NULL, NULL, NULL, NULL };
 
 	flag = pw_properties_get(session->props, NAME ".streams-follow-default");
 	impl->streams_follow_default = (flag != NULL && pw_properties_parse_bool(flag));

src/modules/module-protocol-pulse/pulse-server.c

@@ -139,8 +139,8 @@ struct client {
 	uint32_t subscribed;
 
 	struct pw_manager_object *metadata_default;
-	uint32_t default_sink;
+	char *default_sink;
-	uint32_t default_source;
+	char *default_source;
 	struct pw_manager_object *metadata_routes;
 	struct pw_properties *routes;
 
@@ -899,25 +899,75 @@ static void manager_removed(void *data, struct pw_manager_object *o)
 	send_default_change_subscribe_event(client, object_is_sink(o), object_is_source_or_monitor(o));
 }
 
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
+{
+	struct spa_json it[2];
+	const char *v;
+	char k[128];
+
+	spa_json_init(&it[0], obj, strlen(obj));
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
+
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
+		if (strcmp(k, key) == 0) {
+			if (spa_json_get_string(&it[1], value, len) <= 0)
+				continue;
+			return 0;
+		} else {
+			if (spa_json_next(&it[1], &v) <= 0)
+				break;
+		}
+	}
+	return -ENOENT;
+}
+
+static inline int strzcmp(const char *s1, const char *s2)
+{
+	if (s1 == s2)
+		return 0;
+	if (s1 == NULL || s2 == NULL)
+		return 1;
+	return strcmp(s1, s2);
+}
+
 static void manager_metadata(void *data, struct pw_manager_object *o,
 		uint32_t subject, const char *key, const char *type, const char *value)
 {
 	struct client *client = data;
-	uint32_t val;
 	bool changed = false;
 
 	pw_log_debug("meta id:%d subject:%d key:%s type:%s value:%s",
 			o->id, subject, key, type, value);
 
 	if (subject == PW_ID_CORE && o == client->metadata_default) {
-		val = (key && value) ? (uint32_t)atoi(value) : SPA_ID_INVALID;
+		char name[1024];
+
 		if (key == NULL || strcmp(key, "default.audio.sink") == 0) {
-			changed = client->default_sink != val;
+			if (value != NULL) {
-			client->default_sink = val;
+				if (json_object_find(value,
+						"name", name, sizeof(name)) < 0)
+					value = NULL;
+				else
+					value = name;
+			}
+			if ((changed = strzcmp(client->default_sink, value))) {
+				free(client->default_sink);
+				client->default_sink = strdup(value);
+			}
 		}
 		if (key == NULL || strcmp(key, "default.audio.source") == 0) {
-			changed = client->default_source != val;
+			if (value != NULL) {
-			client->default_source = val;
+				if (json_object_find(value,
+						"name", name, sizeof(name)) < 0)
+					value = NULL;
+				else
+					value = name;
+			}
+			if ((changed = strzcmp(client->default_source, value))) {
+				free(client->default_source);
+				client->default_source = strdup(value);
+			}
 		}
 		if (changed)
 			send_default_change_subscribe_event(client, true, true);
@@ -2594,11 +2644,13 @@ static const char *get_default(struct client *client, bool sink)
 	spa_zero(sel);
 	if (sink) {
 		sel.type = object_is_sink;
-		sel.id = client->default_sink;
+		sel.key = PW_KEY_NODE_NAME;
+		sel.value = client->default_sink;
 		def = DEFAULT_SINK;
 	} else {
 		sel.type = object_is_source_or_monitor;
-		sel.id = client->default_source;
+		sel.key = PW_KEY_NODE_NAME;
+		sel.value = client->default_source;
 		def = DEFAULT_SOURCE;
 	}
 	sel.accumulate = select_best;
@@ -4801,7 +4853,7 @@ static int do_set_default(struct client *client, uint32_t command, uint32_t tag,
 	if ((res = pw_manager_set_metadata(manager, client->metadata_default,
 			PW_ID_CORE,
 			sink ? METADATA_CONFIG_DEFAULT_SINK : METADATA_CONFIG_DEFAULT_SOURCE,
-			SPA_TYPE_INFO_BASE"Id", "%d", o->id)) < 0)
+			"Spa:String:JSON", "{ \"name\": \"%s\" }", name)) < 0)
 		return res;
 
 	return reply_simple_ack(client, tag);
@@ -5280,6 +5332,8 @@ static void client_free(struct client *client)
 		client->disconnecting = true;
 		pw_core_disconnect(client->core);
 	}
+	free(client->default_sink);
+	free(client->default_source);
 	if (client->props)
 		pw_properties_free(client->props);
 	if (client->routes)

src/tools/pw-cat.c

@@ -42,6 +42,7 @@
 #include <spa/param/audio/type-info.h>
 #include <spa/param/props.h>
 #include <spa/utils/result.h>
+#include <spa/utils/json.h>
 #include <spa/debug/types.h>
 
 #include <pipewire/pipewire.h>
@@ -105,8 +106,8 @@ struct data {
 	struct spa_hook registry_listener;
 	struct pw_metadata *metadata;
 	struct spa_hook metadata_listener;
-	uint32_t default_sink;
+	char default_sink[1024];
-	uint32_t default_source;
+	char default_source[1024];
 
 	struct pw_stream *stream;
 	struct spa_hook stream_listener;
@@ -647,17 +648,47 @@ static const struct pw_core_events core_events = {
 	.error = on_core_error,
 };
 
+static int json_object_find(const char *obj, const char *key, char *value, size_t len)
+{
+	struct spa_json it[2];
+	const char *v;
+	char k[128];
+
+	spa_json_init(&it[0], obj, strlen(obj));
+	if (spa_json_enter_object(&it[0], &it[1]) <= 0)
+		return -EINVAL;
+
+	while (spa_json_get_string(&it[1], k, sizeof(k)-1) > 0) {
+		if (strcmp(k, key) == 0) {
+			if (spa_json_get_string(&it[1], value, len) <= 0)
+				continue;
+			return 0;
+		} else {
+			if (spa_json_next(&it[1], &v) <= 0)
+				break;
+		}
+	}
+	return -ENOENT;
+}
+
 static int metadata_property(void *object,
 		uint32_t subject, const char *key, const char *type, const char *value)
 {
 	struct data *data = object;
 
 	if (subject == PW_ID_CORE) {
-		uint32_t val = (key && value) ? (uint32_t)atoi(value) : SPA_ID_INVALID;
+		if (key == NULL || strcmp(key, "default.audio.sink") == 0) {
-		if (key == NULL || strcmp(key, "default.audio.sink") == 0)
+			if (value == NULL ||
-			data->default_sink = val;
+			    json_object_find(value, "name",
-		if (key == NULL || strcmp(key, "default.audio.source") == 0)
+					data->default_sink, sizeof(data->default_sink)) < 0)
-			data->default_source = val;
+				data->default_sink[0] = '\0';
+		}
+		if (key == NULL || strcmp(key, "default.audio.source") == 0) {
+			if (value == NULL ||
+			    json_object_find(value, "name",
+					data->default_source, sizeof(data->default_source)) < 0)
+				data->default_source[0] = '\0';
+		}
 	}
 	return 0;
 }
@@ -1326,7 +1357,6 @@ int main(int argc, char *argv[])
 	struct spa_pod_builder b = SPA_POD_BUILDER_INIT(buffer, sizeof(buffer));
 	const char *prog;
 	int exit_code = EXIT_FAILURE, c, ret;
-	struct target *target, *target_default;
 	enum pw_stream_flags flags = 0;
 
 	pw_init(&argc, &argv);
@@ -1339,9 +1369,6 @@ int main(int argc, char *argv[])
 	else
 		prog = argv[0];
 
-	data.default_source = SPA_ID_INVALID;
-	data.default_sink = SPA_ID_INVALID;
-
 	/* prime the mode from the program name */
 	if (!strcmp(prog, "pw-play"))
 		data.mode = mode_playback;
@@ -1676,9 +1703,10 @@ int main(int argc, char *argv[])
 			exit_code = EXIT_SUCCESS;
 	} else {
 		if (data.targets_listed) {
-			uint32_t default_id;
+			struct target *target, *target_default;
+			char *default_name;
 
-			default_id = (data.mode == mode_record) ?
+			default_name = (data.mode == mode_record) ?
 				data.default_source : data.default_sink;
 
 			exit_code = EXIT_SUCCESS;
@@ -1687,12 +1715,12 @@ int main(int argc, char *argv[])
 			target_default = NULL;
 			spa_list_for_each(target, &data.targets, link) {
 				if (target_default == NULL ||
-				    default_id == target->id ||
+				    strcmp(default_name, target->name) == 0 ||
-				    (default_id == SPA_ID_INVALID &&
+				    (default_name[0] == '\0' &&
 				     target->prio > target_default->prio))
 					target_default = target;
 			}
-			printf("Available targets (\"*\" denotes default): %d\n", default_id);
+			printf("Available targets (\"*\" denotes default): %s\n", default_name);
 			spa_list_for_each(target, &data.targets, link) {
 				printf("%s\t%"PRIu32": description=\"%s\" prio=%d\n",
 				       target == target_default ? "*" : "",
@@ -1703,6 +1731,7 @@ int main(int argc, char *argv[])
 
 	/* destroy targets */
 	while (!spa_list_is_empty(&data.targets)) {
+		struct target *target;
 		target = spa_list_last(&data.targets, struct target, link);
 		spa_list_remove(&target->link);
 		target_destroy(target);