diff options
| -rw-r--r-- | src/libsystemd/sd-bus/bus-objects.c | 369 | ||||
| -rw-r--r-- | src/libsystemd/sd-bus/test-bus-objects.c | 48 | ||||
| -rw-r--r-- | src/systemd/sd-bus.h | 2 |
3 files changed, 419 insertions, 0 deletions
diff --git a/src/libsystemd/sd-bus/bus-objects.c b/src/libsystemd/sd-bus/bus-objects.c index e64743fa58..fc6c223283 100644 --- a/src/libsystemd/sd-bus/bus-objects.c +++ b/src/libsystemd/sd-bus/bus-objects.c @@ -2111,6 +2111,375 @@ _public_ int sd_bus_emit_properties_changed( return sd_bus_emit_properties_changed_strv(bus, path, interface, names); } +static int object_added_append_all_prefix( + sd_bus *bus, + sd_bus_message *m, + Set *s, + const char *prefix, + const char *path, + bool require_fallback) { + + const char *previous_interface = NULL; + struct node_vtable *c; + struct node *n; + int r; + + assert(bus); + assert(m); + assert(s); + assert(prefix); + assert(path); + + n = hashmap_get(bus->nodes, prefix); + if (!n) + return 0; + + LIST_FOREACH(vtables, c, n->vtables) { + _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; + void *u = NULL; + + if (require_fallback && !c->is_fallback) + continue; + + r = node_vtable_get_userdata(bus, path, c, &u, &error); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + if (r == 0) + continue; + + if (!streq_ptr(c->interface, previous_interface)) { + /* If a child-node already handled this interface, we + * skip it on any of its parents. The child vtables + * always fully override any conflicting vtables of + * any parent node. */ + if (set_get(s, c->interface)) + continue; + + r = set_put(s, c->interface); + if (r < 0) + return r; + + if (previous_interface) { + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + } + + r = sd_bus_message_open_container(m, 'e', "sa{sv}"); + if (r < 0) + return r; + r = sd_bus_message_append(m, "s", c->interface); + if (r < 0) + return r; + r = sd_bus_message_open_container(m, 'a', "{sv}"); + if (r < 0) + return r; + + previous_interface = c->interface; + } + + r = vtable_append_all_properties(bus, m, path, c, u, &error); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + } + + if (previous_interface) { + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + } + + return 0; +} + +static int object_added_append_all(sd_bus *bus, sd_bus_message *m, const char *path) { + _cleanup_set_free_ Set *s = NULL; + char *prefix; + int r; + + assert(bus); + assert(m); + assert(path); + + /* + * This appends all interfaces registered on path @path. We first add + * the builtin interfaces, which are always available and handled by + * sd-bus. Then, we add all interfaces registered on the exact node, + * followed by all fallback interfaces registered on any parent prefix. + * + * If an interface is registered multiple times on the same node with + * different vtables, we merge all the properties across all vtables. + * However, if a child node has the same interface registered as one of + * its parent nodes has as fallback, we make the child overwrite the + * parent instead of extending it. Therefore, we keep a "Set" of all + * handled interfaces during parent traversal, so we skip interfaces on + * a parent that were overwritten by a child. + */ + + s = set_new(&string_hash_ops); + if (!s) + return -ENOMEM; + + r = sd_bus_message_append(m, "{sa{sv}}", "org.freedesktop.DBus.Peer", 0); + if (r < 0) + return r; + r = sd_bus_message_append(m, "{sa{sv}}", "org.freedesktop.DBus.Introspectable", 0); + if (r < 0) + return r; + r = sd_bus_message_append(m, "{sa{sv}}", "org.freedesktop.DBus.Properties", 0); + if (r < 0) + return r; + r = sd_bus_message_append(m, "{sa{sv}}", "org.freedesktop.DBus.ObjectManager", 0); + if (r < 0) + return r; + + r = object_added_append_all_prefix(bus, m, s, path, path, false); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + + prefix = alloca(strlen(path) + 1); + OBJECT_PATH_FOREACH_PREFIX(prefix, path) { + r = object_added_append_all_prefix(bus, m, s, prefix, path, true); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + } + + return 0; +} + +int sd_bus_emit_object_added(sd_bus *bus, const char *path) { + BUS_DONT_DESTROY(bus); + + _cleanup_bus_message_unref_ sd_bus_message *m = NULL; + int r; + + /* + * This emits an InterfacesAdded signal on the given path, by iterating + * all registered vtables and fallback vtables on the path. All + * properties are queried and included in the signal. + * This call is equivalent to sd_bus_emit_interfaces_added() with an + * explicit list of registered interfaces. However, unlike + * interfaces_added(), this call can figure out the list of supported + * interfaces itself. Furthermore, it properly adds the builtin + * org.freedesktop.DBus.* interfaces. + */ + + assert_return(bus, -EINVAL); + assert_return(object_path_is_valid(path), -EINVAL); + assert_return(!bus_pid_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + do { + bus->nodes_modified = false; + m = sd_bus_message_unref(m); + + r = sd_bus_message_new_signal(bus, &m, path, "org.freedesktop.DBus.ObjectManager", "InterfacesAdded"); + if (r < 0) + return r; + + r = sd_bus_message_append_basic(m, 'o', path); + if (r < 0) + return r; + + r = sd_bus_message_open_container(m, 'a', "{sa{sv}}"); + if (r < 0) + return r; + + r = object_added_append_all(bus, m, path); + if (r < 0) + return r; + + if (bus->nodes_modified) + continue; + + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + + } while (bus->nodes_modified); + + return sd_bus_send(bus, m, NULL); +} + +static int object_removed_append_all_prefix( + sd_bus *bus, + sd_bus_message *m, + Set *s, + const char *prefix, + const char *path, + bool require_fallback) { + + const char *previous_interface = NULL; + struct node_vtable *c; + struct node *n; + int r; + + assert(bus); + assert(m); + assert(s); + assert(prefix); + assert(path); + + n = hashmap_get(bus->nodes, prefix); + if (!n) + return 0; + + LIST_FOREACH(vtables, c, n->vtables) { + _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; + void *u = NULL; + + if (require_fallback && !c->is_fallback) + continue; + if (streq_ptr(c->interface, previous_interface)) + continue; + + /* If a child-node already handled this interface, we + * skip it on any of its parents. The child vtables + * always fully override any conflicting vtables of + * any parent node. */ + if (set_get(s, c->interface)) + continue; + + r = node_vtable_get_userdata(bus, path, c, &u, &error); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + if (r == 0) + continue; + + r = set_put(s, c->interface); + if (r < 0) + return r; + + r = sd_bus_message_append(m, "s", c->interface); + if (r < 0) + return r; + + previous_interface = c->interface; + } + + return 0; +} + +static int object_removed_append_all(sd_bus *bus, sd_bus_message *m, const char *path) { + _cleanup_set_free_ Set *s = NULL; + char *prefix; + int r; + + assert(bus); + assert(m); + assert(path); + + /* see sd_bus_emit_object_added() for details */ + + s = set_new(&string_hash_ops); + if (!s) + return -ENOMEM; + + r = sd_bus_message_append(m, "s", "org.freedesktop.DBus.Peer"); + if (r < 0) + return r; + r = sd_bus_message_append(m, "s", "org.freedesktop.DBus.Introspectable"); + if (r < 0) + return r; + r = sd_bus_message_append(m, "s", "org.freedesktop.DBus.Properties"); + if (r < 0) + return r; + r = sd_bus_message_append(m, "s", "org.freedesktop.DBus.ObjectManager"); + if (r < 0) + return r; + + r = object_removed_append_all_prefix(bus, m, s, path, path, false); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + + prefix = alloca(strlen(path) + 1); + OBJECT_PATH_FOREACH_PREFIX(prefix, path) { + r = object_removed_append_all_prefix(bus, m, s, prefix, path, true); + if (r < 0) + return r; + if (bus->nodes_modified) + return 0; + } + + return 0; +} + +int sd_bus_emit_object_removed(sd_bus *bus, const char *path) { + BUS_DONT_DESTROY(bus); + + _cleanup_bus_message_unref_ sd_bus_message *m = NULL; + int r; + + /* + * This is like sd_bus_emit_object_added(), but emits an + * InterfacesRemoved signal on the given path. This only includes any + * registered interfaces but skips the properties. Note that this will + * call into the find() callbacks of any registered vtable. Therefore, + * you must call this function before destroying/unlinking your object. + * Otherwise, the list of interfaces will be incomplete. However, note + * that this will *NOT* call into any property callback. Therefore, the + * object might be in an "destructed" state, as long as we can find it. + */ + + assert_return(bus, -EINVAL); + assert_return(object_path_is_valid(path), -EINVAL); + assert_return(!bus_pid_changed(bus), -ECHILD); + + if (!BUS_IS_OPEN(bus->state)) + return -ENOTCONN; + + do { + bus->nodes_modified = false; + m = sd_bus_message_unref(m); + + r = sd_bus_message_new_signal(bus, &m, path, "org.freedesktop.DBus.ObjectManager", "InterfacesRemoved"); + if (r < 0) + return r; + + r = sd_bus_message_append_basic(m, 'o', path); + if (r < 0) + return r; + + r = sd_bus_message_open_container(m, 'a', "s"); + if (r < 0) + return r; + + r = object_removed_append_all(bus, m, path); + if (r < 0) + return r; + + if (bus->nodes_modified) + continue; + + r = sd_bus_message_close_container(m); + if (r < 0) + return r; + + } while (bus->nodes_modified); + + return sd_bus_send(bus, m, NULL); +} + static int interfaces_added_append_one_prefix( sd_bus *bus, sd_bus_message *m, diff --git a/src/libsystemd/sd-bus/test-bus-objects.c b/src/libsystemd/sd-bus/test-bus-objects.c index 06b8904f13..acf67a52b3 100644 --- a/src/libsystemd/sd-bus/test-bus-objects.c +++ b/src/libsystemd/sd-bus/test-bus-objects.c @@ -176,6 +176,28 @@ static int emit_interfaces_removed(sd_bus *bus, sd_bus_message *m, void *userdat return 1; } +static int emit_object_added(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) { + int r; + + assert_se(sd_bus_emit_object_added(bus, m->path) >= 0); + + r = sd_bus_reply_method_return(m, NULL); + assert_se(r >= 0); + + return 1; +} + +static int emit_object_removed(sd_bus *bus, sd_bus_message *m, void *userdata, sd_bus_error *error) { + int r; + + assert_se(sd_bus_emit_object_removed(bus, m->path) >= 0); + + r = sd_bus_reply_method_return(m, NULL); + assert_se(r >= 0); + + return 1; +} + static const sd_bus_vtable vtable[] = { SD_BUS_VTABLE_START(0), SD_BUS_METHOD("AlterSomething", "s", "s", something_handler, 0), @@ -186,6 +208,8 @@ static const sd_bus_vtable vtable[] = { SD_BUS_METHOD("NoOperation", NULL, NULL, NULL, 0), SD_BUS_METHOD("EmitInterfacesAdded", NULL, NULL, emit_interfaces_added, 0), SD_BUS_METHOD("EmitInterfacesRemoved", NULL, NULL, emit_interfaces_removed, 0), + SD_BUS_METHOD("EmitObjectAdded", NULL, NULL, emit_object_added, 0), + SD_BUS_METHOD("EmitObjectRemoved", NULL, NULL, emit_object_removed, 0), SD_BUS_VTABLE_END }; @@ -456,6 +480,30 @@ static int client(struct context *c) { sd_bus_message_unref(reply); reply = NULL; + r = sd_bus_call_method(bus, "org.freedesktop.systemd.test", "/foo", "org.freedesktop.systemd.test", "EmitObjectAdded", &error, NULL, ""); + assert_se(r >= 0); + + r = sd_bus_process(bus, &reply); + assert_se(r > 0); + + assert_se(sd_bus_message_is_signal(reply, "org.freedesktop.DBus.ObjectManager", "InterfacesAdded")); + bus_message_dump(reply, stdout, BUS_MESSAGE_DUMP_WITH_HEADER); + + sd_bus_message_unref(reply); + reply = NULL; + + r = sd_bus_call_method(bus, "org.freedesktop.systemd.test", "/foo", "org.freedesktop.systemd.test", "EmitObjectRemoved", &error, NULL, ""); + assert_se(r >= 0); + + r = sd_bus_process(bus, &reply); + assert_se(r > 0); + + assert_se(sd_bus_message_is_signal(reply, "org.freedesktop.DBus.ObjectManager", "InterfacesRemoved")); + bus_message_dump(reply, stdout, BUS_MESSAGE_DUMP_WITH_HEADER); + + sd_bus_message_unref(reply); + reply = NULL; + r = sd_bus_call_method(bus, "org.freedesktop.systemd.test", "/foo", "org.freedesktop.systemd.test", "Exit", &error, NULL, ""); assert_se(r >= 0); diff --git a/src/systemd/sd-bus.h b/src/systemd/sd-bus.h index 300b949a4b..4f253a1567 100644 --- a/src/systemd/sd-bus.h +++ b/src/systemd/sd-bus.h @@ -310,6 +310,8 @@ int sd_bus_emit_signal(sd_bus *bus, const char *path, const char *interface, con int sd_bus_emit_properties_changed_strv(sd_bus *bus, const char *path, const char *interface, char **names); int sd_bus_emit_properties_changed(sd_bus *bus, const char *path, const char *interface, const char *name, ...) _sd_sentinel_; +int sd_bus_emit_object_added(sd_bus *bus, const char *path); +int sd_bus_emit_object_removed(sd_bus *bus, const char *path); int sd_bus_emit_interfaces_added_strv(sd_bus *bus, const char *path, char **interfaces); int sd_bus_emit_interfaces_added(sd_bus *bus, const char *path, const char *interface, ...) _sd_sentinel_; int sd_bus_emit_interfaces_removed_strv(sd_bus *bus, const char *path, char **interfaces); |