media-session: improve cleanup of objects

Don't try to use the proxy destroy event to destroy the objects.
It is not called automatically anymore, only when we call
pw_proxy_destroy() ourselves.

Destroy the proxy objects when we destroy the session managed
object instead, either when the global is removed or when we
explicitly call _destroy()

Add an object free signal to clean up final resources after the
proxies have been destroyed, like closing libraries.

Track and destroy our link proxies.

src/examples/media-session/alsa-monitor.c

@@ -604,9 +604,27 @@ static void device_destroy(void *data)
 	struct node *node;
 
 	pw_log_debug("device %p destroy", device);
+	spa_list_remove(&device->link);
 
 	spa_list_consume(node, &device->node_list, link)
 		alsa_remove_node(device, node);
+
+	if (device->appeared)
+		spa_hook_remove(&device->device_listener);
+	if (device->seq != 0)
+		spa_hook_remove(&device->sync_listener);
+	if (device->reserve)
+		rd_device_destroy(device->reserve);
+}
+
+static void device_free(void *data)
+{
+	struct device *device = data;
+	pw_log_debug("device %p free", device);
+	spa_hook_remove(&device->listener);
+	pw_unload_spa_handle(device->handle);
+	pw_properties_free(device->props);
+	free(device);
 }
 
 static void device_update(void *data)
@@ -631,6 +649,7 @@ static void device_update(void *data)
 static const struct sm_object_events device_events = {
 	SM_VERSION_OBJECT_EVENTS,
 	.destroy = device_destroy,
+	.free = device_free,
 	.update = device_update,
 };
 
@@ -729,21 +748,9 @@ exit:
 
 static void alsa_remove_device(struct impl *impl, struct device *device)
 {
-	pw_log_debug("remove device %u", device->id);
+	pw_log_debug("%p: remove device %u", device, device->id);
-	spa_list_remove(&device->link);
+	if (device->sdevice)
-	if (device->appeared)
-		spa_hook_remove(&device->device_listener);
-	if (device->seq != 0)
-		spa_hook_remove(&device->sync_listener);
-	if (device->reserve)
-		rd_device_destroy(device->reserve);
-	if (device->sdevice) {
 		sm_object_destroy(&device->sdevice->obj);
-		spa_hook_remove(&device->listener);
-	}
-	pw_unload_spa_handle(device->handle);
-	pw_properties_free(device->props);
-	free(device);
 }
 
 static void alsa_udev_object_info(void *data, uint32_t id,

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

@@ -42,6 +42,7 @@
 #include <spa/monitor/device.h>
 
 #include "pipewire/pipewire.h"
+#include "pipewire/private.h"
 #include "extensions/session-manager.h"
 
 #include <dbus/dbus.h>
@@ -54,6 +55,7 @@
 
 #define sm_object_emit_update(s)		sm_object_emit(s, update, 0)
 #define sm_object_emit_destroy(s)		sm_object_emit(s, destroy, 0)
+#define sm_object_emit_free(s)			sm_object_emit(s, free, 0)
 
 #define sm_media_session_emit(s,m,v,...) spa_hook_list_call(&(s)->hooks, struct sm_media_session_events, m, v, ##__VA_ARGS__)
 
@@ -237,17 +239,56 @@ int sm_object_remove_data(struct sm_object *obj, const char *id)
 
 int sm_object_destroy(struct sm_object *obj)
 {
-	pw_log_debug(NAME" %p: object %d", obj->session, obj->id);
+	struct impl *impl = SPA_CONTAINER_OF(obj->session, struct impl, this);
-	if (obj->proxy) {
+	struct data *d;
-		pw_proxy_destroy(obj->proxy);
+	struct pw_proxy *p, *h;
-		if (obj->handle == obj->proxy)
+
-			obj->handle = NULL;
+	p = obj->proxy;
-		obj->proxy = NULL;
+	h = obj->handle;
+
+	pw_log_debug(NAME" %p: object %d proxy:%p handle:%p", obj->session,
+			obj->id, p, h);
+
+	sm_object_emit_destroy(obj);
+
+	if (SPA_FLAG_IS_SET(obj->mask, SM_OBJECT_CHANGE_MASK_LISTENER)) {
+		SPA_FLAG_CLEAR(obj->mask, SM_OBJECT_CHANGE_MASK_LISTENER);
+		spa_hook_remove(&obj->object_listener);
 	}
-	if (obj->handle) {
+
-		pw_proxy_destroy(obj->handle);
+	if (obj->id != SPA_ID_INVALID)
-		obj->handle = NULL;
+		remove_object(impl, obj);
+
+	if (obj->destroy)
+		obj->destroy(obj);
+
+	if (p) {
+		pw_proxy_ref(p);
+		spa_hook_remove(&obj->proxy_listener);
 	}
+	if (h) {
+		pw_proxy_ref(h);
+		spa_hook_remove(&obj->handle_listener);
+	}
+	if (p)
+		pw_proxy_destroy(p);
+	if (h != p)
+		pw_proxy_destroy(h);
+
+	sm_object_emit_free(obj);
+
+	if (obj->props)
+		pw_properties_free(obj->props);
+	obj->props = NULL;
+
+	spa_list_consume(d, &obj->data, link) {
+		spa_list_remove(&d->link);
+		free(d);
+	}
+	if (p)
+		pw_proxy_unref(p);
+	if (h)
+		pw_proxy_unref(h);
 	return 0;
 }
 
@@ -911,46 +952,6 @@ static const struct object_info endpoint_link_info = {
 /**
  * Proxy
  */
-static void
-destroy_proxy(void *data)
-{
-	struct sm_object *obj = data;
-	struct impl *impl = SPA_CONTAINER_OF(obj->session, struct impl, this);
-	struct data *d;
-
-	pw_log_debug("object %p: proxy:%p id:%d", obj, obj->proxy, obj->id);
-
-	if (SPA_FLAG_IS_SET(obj->mask, SM_OBJECT_CHANGE_MASK_LISTENER)) {
-		SPA_FLAG_CLEAR(obj->mask, SM_OBJECT_CHANGE_MASK_LISTENER);
-		spa_hook_remove(&obj->object_listener);
-	}
-
-	if (obj->id != SPA_ID_INVALID)
-		remove_object(impl, obj);
-
-	sm_object_emit_destroy(obj);
-
-	if (obj->destroy)
-		obj->destroy(obj);
-
-	if (obj->proxy) {
-		spa_hook_remove(&obj->proxy_listener);
-		obj->proxy = NULL;
-	}
-	if (obj->handle) {
-		spa_hook_remove(&obj->handle_listener);
-		obj->handle = NULL;
-	}
-	if (obj->props)
-		pw_properties_free(obj->props);
-	obj->props = NULL;
-
-	spa_list_consume(d, &obj->data, link) {
-		spa_list_remove(&d->link);
-		free(d);
-	}
-}
-
 static void done_proxy(void *data, int seq)
 {
 	struct sm_object *obj = data;
@@ -980,7 +981,6 @@ static void bound_proxy(void *data, uint32_t id)
 
 static const struct pw_proxy_events proxy_events = {
 	PW_VERSION_PROXY_EVENTS,
-	.destroy = destroy_proxy,
 	.done = done_proxy,
 	.bound = bound_proxy,
 };
@@ -1074,7 +1074,8 @@ create_object(struct impl *impl, struct pw_proxy *proxy, struct pw_proxy *handle
 	}
 	obj = init_object(impl, info, proxy, handle, SPA_ID_INVALID, props);
 
-	pw_log_debug(NAME" %p: created new object %p proxy %p", impl, obj, obj->proxy);
+	pw_log_debug(NAME" %p: created new object %p proxy:%p handle:%p", impl,
+			obj, obj->proxy, obj->handle);
 
 	return obj;
 }
@@ -1271,7 +1272,7 @@ registry_global_remove(void *data, uint32_t id)
 	if ((obj = find_object(impl, id)) == NULL)
 		return;
 
-	remove_object(impl, obj);
+	sm_object_destroy(obj);
 }
 
 static const struct pw_registry_events registry_events = {
@@ -1391,6 +1392,12 @@ static void check_endpoint_link(struct endpoint_link *link)
 	}
 }
 
+static void proxy_link_removed(void *data)
+{
+	struct link *l = data;
+	pw_proxy_destroy(l->proxy);
+}
+
 static void proxy_link_destroy(void *data)
 {
 	struct link *l = data;
@@ -1404,6 +1411,7 @@ static void proxy_link_destroy(void *data)
 
 static const struct pw_proxy_events proxy_link_events = {
 	PW_VERSION_PROXY_EVENTS,
+	.removed = proxy_link_removed,
 	.destroy = proxy_link_destroy
 };
 
@@ -1695,8 +1703,8 @@ static void session_shutdown(struct impl *impl)
 
 	pw_log_info(NAME" %p", impl);
 
-	spa_list_for_each(obj, &impl->global_list, link)
+	spa_list_consume(obj, &impl->global_list, link)
-		sm_media_session_emit_remove(impl, obj);
+		sm_object_destroy(obj);
 
 	sm_media_session_emit_destroy(impl);
 
@@ -1887,6 +1895,7 @@ exit:
 
 	pw_map_clear(&impl.endpoint_links);
 	pw_map_clear(&impl.globals);
+	pw_properties_free(impl.this.props);
 
 	pw_deinit();
 

src/examples/media-session/media-session.h

@@ -43,6 +43,7 @@ struct sm_object_events {
 
 	void (*update) (void *data);
 	void (*destroy) (void *data);
+	void (*free) (void *data);
 };
 
 struct sm_object_methods {

src/examples/media-session/v4l2-monitor.c

@@ -295,9 +295,23 @@ static void device_destroy(void *data)
 	struct node *node;
 
 	pw_log_debug("device %p destroy", device);
+	spa_list_remove(&device->link);
 
 	spa_list_consume(node, &device->node_list, link)
 		v4l2_remove_node(device, node);
+
+	if (device->appeared)
+		spa_hook_remove(&device->device_listener);
+}
+
+static void device_free(void *data)
+{
+	struct device *device = data;
+	pw_log_debug("device %p free", device);
+	spa_hook_remove(&device->listener);
+	pw_unload_spa_handle(device->handle);
+	pw_properties_free(device->props);
+	free(device);
 }
 
 static void device_update(void *data)
@@ -323,10 +337,10 @@ static void device_update(void *data)
 static const struct sm_object_events device_events = {
 	SM_VERSION_OBJECT_EVENTS,
 	.destroy = device_destroy,
+	.free = device_free,
 	.update = device_update,
 };
 
-
 static struct device *v4l2_create_device(struct impl *impl, uint32_t id,
 		const struct spa_device_object_info *info)
 {
@@ -401,15 +415,8 @@ exit:
 static void v4l2_remove_device(struct impl *impl, struct device *dev)
 {
 	pw_log_debug("remove device %u", dev->id);
-	spa_list_remove(&dev->link);
-	if (dev->appeared)
-		spa_hook_remove(&dev->device_listener);
 	if (dev->sdevice)
 		sm_object_destroy(&dev->sdevice->obj);
-	spa_hook_remove(&dev->listener);
-	pw_unload_spa_handle(dev->handle);
-	pw_properties_free(dev->props);
-	free(dev);
 }
 
 static void v4l2_udev_object_info(void *data, uint32_t id,