sd-bus: introduce sd_bus_slot objects encapsulating callbacks or vtables attached to a bus connection

This makes callback behaviour more like sd-event or sd-resolve, and
creates proper object for unregistering callbacks.

Taking the refernce to the slot is optional. If not taken life time of
the slot will be bound to the underlying bus object (or in the case of
an async call until the reply has been recieved).

1 files changed, 55 insertions, 9 deletions

diff --git a/src/libsystemd/sd-bus/bus-internal.h b/src/libsystemd/sd-bus/bus-internal.h
index 3dceb8a5d..042d35226 100644
--- a/src/libsystemd/sd-bus/bus-internal.h
+++ b/src/libsystemd/sd-bus/bus-internal.h
@@ -40,7 +40,6 @@
 
 struct reply_callback {
         sd_bus_message_handler_t callback;
-        void *userdata;
         usec_t timeout;
         uint64_t cookie;
         unsigned prioq_idx;
@@ -48,13 +47,23 @@ struct reply_callback {
 
 struct filter_callback {
         sd_bus_message_handler_t callback;
-        void *userdata;
 
         unsigned last_iteration;
 
         LIST_FIELDS(struct filter_callback, callbacks);
 };
 
+struct match_callback {
+        sd_bus_message_handler_t callback;
+
+        uint64_t cookie;
+        unsigned last_iteration;
+
+        char *match_string;
+
+        struct bus_match_node *match_node;
+};
+
 struct node {
         char *path;
         struct node *parent;
@@ -64,8 +73,7 @@ struct node {
         LIST_HEAD(struct node_callback, callbacks);
         LIST_HEAD(struct node_vtable, vtables);
         LIST_HEAD(struct node_enumerator, enumerators);
-
-        bool object_manager;
+        LIST_HEAD(struct node_object_manager, object_managers);
 };
 
 struct node_callback {
@@ -73,7 +81,6 @@ struct node_callback {
 
         bool is_fallback;
         sd_bus_message_handler_t callback;
-        void *userdata;
 
         unsigned last_iteration;
 
@@ -84,20 +91,24 @@ struct node_enumerator {
         struct node *node;
 
         sd_bus_node_enumerator_t callback;
-        void *userdata;
 
         unsigned last_iteration;
 
         LIST_FIELDS(struct node_enumerator, enumerators);
 };
 
+struct node_object_manager {
+        struct node *node;
+
+        LIST_FIELDS(struct node_object_manager, object_managers);
+};
+
 struct node_vtable {
         struct node *node;
 
         char *interface;
         bool is_fallback;
         const sd_bus_vtable *vtable;
-        void *userdata;
         sd_bus_object_find_t find;
 
         unsigned last_iteration;
@@ -114,6 +125,37 @@ struct vtable_member {
         const sd_bus_vtable *vtable;
 };
 
+typedef enum BusSlotType {
+        _BUS_SLOT_DISCONNECTED,
+        BUS_REPLY_CALLBACK,
+        BUS_FILTER_CALLBACK,
+        BUS_MATCH_CALLBACK,
+        BUS_NODE_CALLBACK,
+        BUS_NODE_ENUMERATOR,
+        BUS_NODE_VTABLE,
+        BUS_NODE_OBJECT_MANAGER,
+} BusSlotType;
+
+struct sd_bus_slot {
+        unsigned n_ref;
+        sd_bus *bus;
+        void *userdata;
+        BusSlotType type;
+        bool floating;
+
+        LIST_FIELDS(sd_bus_slot, slots);
+
+        union {
+                struct reply_callback reply_callback;
+                struct filter_callback filter_callback;
+                struct match_callback match_callback;
+                struct node_callback node_callback;
+                struct node_enumerator node_enumerator;
+                struct node_object_manager node_object_manager;
+                struct node_vtable node_vtable;
+        };
+};
+
 enum bus_state {
         BUS_UNSET,
         BUS_OPENING,
@@ -231,7 +273,6 @@ struct sd_bus {
         char *exec_path;
         char **exec_argv;
 
-        uint64_t hello_cookie;
         unsigned iteration_counter;
 
         void *kdbus_buffer;
@@ -260,7 +301,8 @@ struct sd_bus {
         sd_event *event;
         int event_priority;
 
-        sd_bus_message *current;
+        sd_bus_message *current_message;
+        sd_bus_slot *current_slot;
 
         sd_bus **default_bus_ptr;
         pid_t tid;
@@ -276,6 +318,8 @@ struct sd_bus {
         unsigned bloom_n_hash;
 
         sd_bus_track *track_queue;
+
+        LIST_HEAD(sd_bus_slot, slots);
 };
 
 #define BUS_DEFAULT_TIMEOUT ((usec_t) (25 * USEC_PER_SEC))
@@ -340,3 +384,5 @@ int bus_set_address_system(sd_bus *bus);
 int bus_set_address_user(sd_bus *bus);
 int bus_set_address_system_remote(sd_bus *b, const char *host);
 int bus_set_address_system_container(sd_bus *b, const char *machine);
+
+int bus_remove_match_by_string(sd_bus *bus, const char *match, sd_bus_message_handler_t callback, void *userdata);