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, 244 insertions, 0 deletions

diff --git a/src/libsystemd/sd-bus/bus-slot.c b/src/libsystemd/sd-bus/bus-slot.c
new file mode 100644
index 0000000000..8e38992ec4
--- /dev/null
+++ b/src/libsystemd/sd-bus/bus-slot.c
@@ -0,0 +1,244 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "sd-bus.h"
+#include "bus-control.h"
+#include "bus-objects.h"
+#include "bus-slot.h"
+
+sd_bus_slot *bus_slot_allocate(
+                sd_bus *bus,
+                bool floating,
+                BusSlotType type,
+                size_t extra,
+                void *userdata) {
+
+        sd_bus_slot *slot;
+
+        assert(bus);
+
+        slot = malloc0(offsetof(sd_bus_slot, reply_callback) + extra);
+        if (!slot)
+                return NULL;
+
+        slot->n_ref = 1;
+        slot->type = type;
+        slot->bus = bus;
+        slot->floating = floating;
+        slot->userdata = userdata;
+
+        if (!floating)
+                sd_bus_ref(bus);
+
+        LIST_PREPEND(slots, bus->slots, slot);
+
+        return slot;
+}
+
+_public_ sd_bus_slot* sd_bus_slot_ref(sd_bus_slot *slot) {
+        assert_return(slot, NULL);
+
+        assert(slot->n_ref > 0);
+
+        slot->n_ref++;
+        return slot;
+}
+
+void bus_slot_disconnect(sd_bus_slot *slot) {
+        sd_bus *bus;
+
+        assert(slot);
+
+        switch (slot->type) {
+
+        case _BUS_SLOT_DISCONNECTED:
+                /* Already disconnected... */
+                return;
+
+        case BUS_REPLY_CALLBACK:
+
+                if (slot->reply_callback.cookie != 0)
+                        hashmap_remove(slot->bus->reply_callbacks, &slot->reply_callback.cookie);
+
+                if (slot->reply_callback.timeout != 0)
+                        prioq_remove(slot->bus->reply_callbacks_prioq, &slot->reply_callback, &slot->reply_callback.prioq_idx);
+
+                break;
+
+        case BUS_FILTER_CALLBACK:
+                slot->bus->filter_callbacks_modified = true;
+                LIST_REMOVE(callbacks, slot->bus->filter_callbacks, &slot->filter_callback);
+                break;
+
+        case BUS_MATCH_CALLBACK:
+
+                if (slot->bus->bus_client)
+                        bus_remove_match_internal(slot->bus, slot->match_callback.match_string, slot->match_callback.cookie);
+
+                slot->bus->match_callbacks_modified = true;
+                bus_match_remove(&slot->bus->match_callbacks, &slot->match_callback);
+
+                free(slot->match_callback.match_string);
+
+                break;
+
+        case BUS_NODE_CALLBACK:
+
+                if (slot->node_callback.node) {
+                        LIST_REMOVE(callbacks, slot->node_callback.node->callbacks, &slot->node_callback);
+                        slot->bus->nodes_modified = true;
+
+                        bus_node_gc(slot->bus, slot->node_callback.node);
+                }
+
+                break;
+
+        case BUS_NODE_ENUMERATOR:
+
+                if (slot->node_enumerator.node) {
+                        LIST_REMOVE(enumerators, slot->node_enumerator.node->enumerators, &slot->node_enumerator);
+                        slot->bus->nodes_modified = true;
+
+                        bus_node_gc(slot->bus, slot->node_enumerator.node);
+                }
+
+                break;
+
+        case BUS_NODE_OBJECT_MANAGER:
+
+                if (slot->node_object_manager.node) {
+                        LIST_REMOVE(object_managers, slot->node_object_manager.node->object_managers, &slot->node_object_manager);
+                        slot->bus->nodes_modified = true;
+
+                        bus_node_gc(slot->bus, slot->node_object_manager.node);
+                }
+
+                break;
+
+        case BUS_NODE_VTABLE:
+
+                if (slot->node_vtable.node && slot->node_vtable.interface && slot->node_vtable.vtable) {
+                        const sd_bus_vtable *v;
+
+                        for (v = slot->node_vtable.vtable; v->type != _SD_BUS_VTABLE_END; v++) {
+                                struct vtable_member *x = NULL;
+
+                                switch (v->type) {
+
+                                case _SD_BUS_VTABLE_METHOD: {
+                                        struct vtable_member key;
+
+                                        key.path = slot->node_vtable.node->path;
+                                        key.interface = slot->node_vtable.interface;
+                                        key.member = v->x.method.member;
+
+                                        x = hashmap_remove(slot->bus->vtable_methods, &key);
+                                        break;
+                                }
+
+                                case _SD_BUS_VTABLE_PROPERTY:
+                                case _SD_BUS_VTABLE_WRITABLE_PROPERTY: {
+                                        struct vtable_member key;
+
+                                        key.path = slot->node_vtable.node->path;
+                                        key.interface = slot->node_vtable.interface;
+                                        key.member = v->x.method.member;
+
+
+                                        x = hashmap_remove(slot->bus->vtable_properties, &key);
+                                        break;
+                                }}
+
+                                free(x);
+                        }
+                }
+
+                free(slot->node_vtable.interface);
+
+                if (slot->node_vtable.node) {
+                        LIST_REMOVE(vtables, slot->node_vtable.node->vtables, &slot->node_vtable);
+                        slot->bus->nodes_modified = true;
+
+                        bus_node_gc(slot->bus, slot->node_vtable.node);
+                }
+
+                break;
+        }
+        bus = slot->bus;
+
+        slot->type = _BUS_SLOT_DISCONNECTED;
+        slot->bus = NULL;
+        LIST_REMOVE(slots, bus->slots, slot);
+
+        if (!slot->floating)
+                sd_bus_unref(bus);
+}
+
+_public_ sd_bus_slot* sd_bus_slot_unref(sd_bus_slot *slot) {
+
+        if (!slot)
+                return NULL;
+
+        assert(slot->n_ref > 0);
+
+        if (slot->n_ref > 1) {
+                slot->n_ref --;
+                return NULL;
+        }
+
+        bus_slot_disconnect(slot);
+        free(slot);
+
+        return NULL;
+}
+
+_public_ sd_bus* sd_bus_slot_get_bus(sd_bus_slot *slot) {
+        assert_return(slot, NULL);
+
+        return slot->bus;
+}
+
+_public_ void *sd_bus_slot_get_userdata(sd_bus_slot *slot) {
+        assert_return(slot, NULL);
+
+        return slot->userdata;
+}
+
+_public_ void *sd_bus_slot_set_userdata(sd_bus_slot *slot, void *userdata) {
+        void *ret;
+
+        assert_return(slot, NULL);
+
+        ret = slot->userdata;
+        slot->userdata = userdata;
+
+        return ret;
+}
+
+_public_ sd_bus_message *sd_bus_slot_get_current_message(sd_bus_slot *slot) {
+        assert_return(slot, NULL);
+        assert_return(slot->type != _BUS_SLOT_DISCONNECTED, NULL);
+
+        if (slot->bus->current_slot != slot)
+                return NULL;
+
+        return slot->bus->current_message;
+}