4 files changed, 26 insertions, 0 deletions
diff --git a/src/libelogind/libelogind.sym b/src/libelogind/libelogind.sym
index 9dd25c738..916dfcf83 100644
--- a/src/libelogind/libelogind.sym
+++ b/src/libelogind/libelogind.sym
@@ -569,6 +569,8 @@ global:
         sd_bus_open_system_with_description;
         sd_bus_slot_get_floating;
         sd_bus_slot_set_floating;
+        sd_bus_slot_get_destroy_callback;
+        sd_bus_slot_set_destroy_callback;
         sd_event_add_inotify;
         sd_event_source_get_inotify_mask;
 } LIBSYSTEMD_238;
diff --git a/src/libelogind/sd-bus/bus-internal.h b/src/libelogind/sd-bus/bus-internal.h
index 8f3460ce2..cfe299e01 100644
--- a/src/libelogind/sd-bus/bus-internal.h
+++ b/src/libelogind/sd-bus/bus-internal.h
@@ -127,6 +127,7 @@ struct sd_bus_slot {
         unsigned n_ref;
         sd_bus *bus;
         void *userdata;
+        sd_bus_destroy_t destroy_callback;
         BusSlotType type:5;
 
         /* Slots can be "floating" or not. If they are not floating (the usual case) then they reference the bus object
diff --git a/src/libelogind/sd-bus/bus-slot.c b/src/libelogind/sd-bus/bus-slot.c
index 34cfdd29e..db9af9a97 100644
--- a/src/libelogind/sd-bus/bus-slot.c
+++ b/src/libelogind/sd-bus/bus-slot.c
@@ -203,6 +203,10 @@ _public_ sd_bus_slot* sd_bus_slot_unref(sd_bus_slot *slot) {
         }
 
         bus_slot_disconnect(slot);
+
+        if (slot->destroy_callback)
+                slot->destroy_callback(slot->userdata);
+
         free(slot->description);
         return mfree(slot);
 }
@@ -230,6 +234,22 @@ _public_ void *sd_bus_slot_set_userdata(sd_bus_slot *slot, void *userdata) {
         return ret;
 }
 
+_public_ int sd_bus_slot_set_destroy_callback(sd_bus_slot *slot, sd_bus_destroy_t callback) {
+        assert_return(slot, -EINVAL);
+
+        slot->destroy_callback = callback;
+        return 0;
+}
+
+_public_ int sd_bus_slot_get_destroy_callback(sd_bus_slot *slot, sd_bus_destroy_t *callback) {
+        assert_return(slot, -EINVAL);
+
+        if (callback)
+                *callback = slot->destroy_callback;
+
+        return !!slot->destroy_callback;
+}
+
 _public_ sd_bus_message *sd_bus_slot_get_current_message(sd_bus_slot *slot) {
         assert_return(slot, NULL);
         assert_return(slot->type >= 0, NULL);
diff --git a/src/systemd/sd-bus.h b/src/systemd/sd-bus.h
index cf38e4c63..6a9e361fe 100644
--- a/src/systemd/sd-bus.h
+++ b/src/systemd/sd-bus.h
@@ -111,6 +111,7 @@ typedef int (*sd_bus_property_set_t) (sd_bus *bus, const char *path, const char
 typedef int (*sd_bus_object_find_t) (sd_bus *bus, const char *path, const char *interface, void *userdata, void **ret_found, sd_bus_error *ret_error);
 typedef int (*sd_bus_node_enumerator_t) (sd_bus *bus, const char *prefix, void *userdata, char ***ret_nodes, sd_bus_error *ret_error);
 typedef int (*sd_bus_track_handler_t) (sd_bus_track *track, void *userdata);
+typedef void (*sd_bus_destroy_t)(void *userdata);
 
 #include "sd-bus-protocol.h"
 #include "sd-bus-vtable.h"
@@ -230,6 +231,8 @@ int sd_bus_slot_set_description(sd_bus_slot *slot, const char *description);
 int sd_bus_slot_get_description(sd_bus_slot *slot, const char **description);
 int sd_bus_slot_get_floating(sd_bus_slot *slot);
 int sd_bus_slot_set_floating(sd_bus_slot *slot, int b);
+int sd_bus_slot_set_destroy_callback(sd_bus_slot *s, sd_bus_destroy_t callback);
+int sd_bus_slot_get_destroy_callback(sd_bus_slot *s, sd_bus_destroy_t *callback);
 
 sd_bus_message* sd_bus_slot_get_current_message(sd_bus_slot *slot);
 sd_bus_message_handler_t sd_bus_slot_get_current_handler(sd_bus_slot *bus);