link: listen for permission changes

Destroy the link when the ports or nodes are no longer visible
to the other side of the link.

1 files changed, 26 insertions, 8 deletions

diff --git a/src/pipewire/link.c b/src/pipewire/link.c
index 1e39da58..86c639d9 100644
--- a/src/pipewire/link.c
+++ b/src/pipewire/link.c
@@ -62,8 +62,10 @@ struct impl {
 
 	struct spa_hook input_port_listener;
 	struct spa_hook input_node_listener;
+	struct spa_hook input_global_listener;
 	struct spa_hook output_port_listener;
 	struct spa_hook output_node_listener;
+	struct spa_hook output_global_listener;
 
 	struct spa_io_buffers io;
 
@@ -872,6 +874,7 @@ static void input_remove(struct pw_link *this, struct pw_port *port)
 	pw_log_debug("link %p: remove input port %p", this, port);
 	spa_hook_remove(&impl->input_port_listener);
 	spa_hook_remove(&impl->input_node_listener);
+	spa_hook_remove(&impl->input_global_listener);
 
 	spa_list_remove(&this->input_link);
 	pw_port_emit_link_removed(this->input, this);
@@ -891,6 +894,7 @@ static void output_remove(struct pw_link *this, struct pw_port *port)
 	pw_log_debug("link %p: remove output port %p", this, port);
 	spa_hook_remove(&impl->output_port_listener);
 	spa_hook_remove(&impl->output_node_listener);
+	spa_hook_remove(&impl->output_global_listener);
 
 	spa_list_remove(&this->output_link);
 	pw_port_emit_link_removed(this->output, this);
@@ -1177,22 +1181,34 @@ check_permission(struct pw_core *core,
 		 struct pw_port *input,
 		 struct pw_properties *properties)
 {
-	struct pw_node *input_node, *output_node;
 	struct pw_client *client;
 
-	input_node = input->node;
-	output_node = output->node;
-
-	if ((client = output_node->global->owner) != NULL &&
-	    !PW_PERM_IS_R(pw_global_get_permissions(input_node->global, client)))
+	if ((client = output->global->owner) != NULL &&
+	    !PW_PERM_IS_R(pw_global_get_permissions(input->global, client)))
 		return -EPERM;
 
-	if ((client = input_node->global->owner) != NULL &&
-	    !PW_PERM_IS_R(pw_global_get_permissions(output_node->global, client)))
+	if ((client = input->global->owner) != NULL &&
+	    !PW_PERM_IS_R(pw_global_get_permissions(output->global, client)))
 		return -EPERM;
+
 	return 0;
 }
 
+static void global_permissions_changed(void *data,
+		struct pw_client *client, uint32_t old, uint32_t new)
+{
+	struct pw_link *this = data;
+
+	pw_log_debug("link %p: permissions changed", this);
+	if (check_permission(this->core, this->output, this->input, this->properties) < 0)
+		pw_link_destroy(this);
+}
+
+static const struct pw_global_events global_node_events = {
+	PW_VERSION_GLOBAL_EVENTS,
+	.permissions_changed = global_permissions_changed,
+};
+
 SPA_EXPORT
 struct pw_link *pw_link_new(struct pw_core *core,
 			    struct pw_port *output,
@@ -1254,8 +1270,10 @@ struct pw_link *pw_link_new(struct pw_core *core,
 
 	pw_port_add_listener(input, &impl->input_port_listener, &input_port_events, impl);
 	pw_node_add_listener(input_node, &impl->input_node_listener, &input_node_events, impl);
+	pw_global_add_listener(input_node->global, &impl->input_global_listener, &global_node_events, impl);
 	pw_port_add_listener(output, &impl->output_port_listener, &output_port_events, impl);
 	pw_node_add_listener(output_node, &impl->output_node_listener, &output_node_events, impl);
+	pw_global_add_listener(output_node->global, &impl->output_global_listener, &global_node_events, impl);
 
 	input_node->live = output_node->live;