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, 31 insertions, 28 deletions

diff --git a/src/libsystemd/sd-bus/bus-track.c b/src/libsystemd/sd-bus/bus-track.c
index 0f6a2eafbd..ffa2cf3d75 100644
--- a/src/libsystemd/sd-bus/bus-track.c
+++ b/src/libsystemd/sd-bus/bus-track.c
@@ -21,6 +21,7 @@
 
 #include "sd-bus.h"
 #include "set.h"
+#include "bus-util.h"
 #include "bus-internal.h"
 #include "bus-track.h"
 
@@ -29,7 +30,7 @@ struct sd_bus_track {
         sd_bus *bus;
         sd_bus_track_handler_t handler;
         void *userdata;
-        Set *names;
+        Hashmap *names;
         LIST_FIELDS(sd_bus_track, queue);
         Iterator iterator;
         bool in_queue;
@@ -128,11 +129,11 @@ _public_ sd_bus_track* sd_bus_track_unref(sd_bus_track *track) {
                 return NULL;
         }
 
-        while ((n = set_first(track->names)))
+        while ((n = hashmap_first_key(track->names)))
                 sd_bus_track_remove_name(track, n);
 
         bus_track_remove_from_queue(track);
-        set_free(track->names);
+        hashmap_free(track->names);
         sd_bus_unref(track->bus);
         free(track);
 
@@ -157,6 +158,7 @@ static int on_name_owner_changed(sd_bus *bus, sd_bus_message *message, void *use
 }
 
 _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) {
+        _cleanup_bus_slot_unref_ sd_bus_slot *slot = NULL;
         _cleanup_free_ char *n = NULL;
         const char *match;
         int r;
@@ -164,7 +166,7 @@ _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) {
         assert_return(track, -EINVAL);
         assert_return(service_name_is_valid(name), -EINVAL);
 
-        r = set_ensure_allocated(&track->names, string_hash_func, string_compare_func);
+        r = hashmap_ensure_allocated(&track->names, string_hash_func, string_compare_func);
         if (r < 0)
                 return r;
 
@@ -172,30 +174,28 @@ _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) {
         if (!n)
                 return -ENOMEM;
 
-        r = set_put(track->names, n);
+        /* First, subscribe to this name */
+        match = MATCH_FOR_NAME(n);
+        r = sd_bus_add_match(track->bus, &slot, match, on_name_owner_changed, track);
+        if (r < 0)
+                return r;
+
+        r = hashmap_put(track->names, n, slot);
         if (r == -EEXIST)
                 return 0;
         if (r < 0)
                 return r;
 
-        /* First, subscribe to this name */
-        match = MATCH_FOR_NAME(name);
-        r = sd_bus_add_match(track->bus, match, on_name_owner_changed, track);
-        if (r < 0) {
-                set_remove(track->names, n);
-                return r;
-        }
-
         /* Second, check if it is currently existing, or maybe
          * doesn't, or maybe disappeared already. */
-        r = sd_bus_get_owner(track->bus, name, 0, NULL);
+        r = sd_bus_get_owner(track->bus, n, 0, NULL);
         if (r < 0) {
-                set_remove(track->names, n);
-                sd_bus_remove_match(track->bus, match, on_name_owner_changed, track);
+                hashmap_remove(track->names, n);
                 return r;
         }
 
         n = NULL;
+        slot = NULL;
 
         bus_track_remove_from_queue(track);
         track->modified = true;
@@ -204,22 +204,19 @@ _public_ int sd_bus_track_add_name(sd_bus_track *track, const char *name) {
 }
 
 _public_ int sd_bus_track_remove_name(sd_bus_track *track, const char *name) {
-        const char *match;
-        _cleanup_free_ char *n = NULL;;
+        _cleanup_bus_slot_unref_ sd_bus_slot *slot = NULL;
+        _cleanup_free_ char *n = NULL;
 
         assert_return(name, -EINVAL);
 
         if (!track)
                 return 0;
 
-        n = set_remove(track->names, (char*) name);
-        if (!n)
+        slot = hashmap_remove2(track->names, (char*) name, (void**) &n);
+        if (!slot)
                 return 0;
 
-        match = MATCH_FOR_NAME(n);
-        sd_bus_remove_match(track->bus, match, on_name_owner_changed, track);
-
-        if (set_isempty(track->names))
+        if (hashmap_isempty(track->names))
                 bus_track_add_to_queue(track);
 
         track->modified = true;
@@ -231,34 +228,40 @@ _public_ unsigned sd_bus_track_count(sd_bus_track *track) {
         if (!track)
                 return 0;
 
-        return set_size(track->names);
+        return hashmap_size(track->names);
 }
 
 _public_ const char* sd_bus_track_contains(sd_bus_track *track, const char *name) {
         assert_return(track, NULL);
         assert_return(name, NULL);
 
-        return set_get(track->names, (void*) name);
+        return hashmap_get(track->names, (void*) name) ? name : NULL;
 }
 
 _public_ const char* sd_bus_track_first(sd_bus_track *track) {
+        const char *n = NULL;
+
         if (!track)
                 return NULL;
 
         track->modified = false;
         track->iterator = NULL;
 
-        return set_iterate(track->names, &track->iterator);
+        hashmap_iterate(track->names, &track->iterator, (const void**) &n);
+        return n;
 }
 
 _public_ const char* sd_bus_track_next(sd_bus_track *track) {
+        const char *n = NULL;
+
         if (!track)
                 return NULL;
 
         if (track->modified)
                 return NULL;
 
-        return set_iterate(track->names, &track->iterator);
+        hashmap_iterate(track->names, &track->iterator, (const void**) &n);
+        return n;
 }
 
 _public_ int sd_bus_track_add_sender(sd_bus_track *track, sd_bus_message *m) {