// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018 Red Hat, Inc.
*/
#include "nm-default.h"
#include "nm-dbus-object.h"
#include "nm-dbus-manager.h"
/*****************************************************************************/
enum {
EXPORTED_CHANGED,
LAST_SIGNAL,
};
static guint signals[LAST_SIGNAL] = { 0 };
G_DEFINE_ABSTRACT_TYPE (NMDBusObject, nm_dbus_object, G_TYPE_OBJECT);
/*****************************************************************************/
#define _NMLOG_DOMAIN LOGD_CORE
#define _NMLOG(level, ...) __NMLOG_DEFAULT_WITH_ADDR (level, _NMLOG_DOMAIN, "dbus-object", __VA_ARGS__)
#define _NMLOG2_DOMAIN LOGD_DBUS_PROPS
#define _NMLOG2(level, ...) __NMLOG_DEFAULT_WITH_ADDR (level, _NMLOG2_DOMAIN, "properties-changed", __VA_ARGS__)
/*****************************************************************************/
static void
_emit_exported_changed (NMDBusObject *self)
{
g_signal_emit (self, signals[EXPORTED_CHANGED], 0);
}
static char *
_create_export_path (NMDBusObjectClass *klass)
{
nm_assert (NM_IS_DBUS_OBJECT_CLASS (klass));
nm_assert (klass->export_path.path);
#if NM_MORE_ASSERTS
{
const char *p;
p = strchr (klass->export_path.path, '%');
if (klass->export_path.int_counter) {
nm_assert (p);
nm_assert (p[1] == 'l');
nm_assert (p[2] == 'l');
nm_assert (p[3] == 'u');
nm_assert (p[4] == '\0');
} else
nm_assert (!p);
}
#endif
if (klass->export_path.int_counter) {
NM_PRAGMA_WARNING_DISABLE("-Wformat-nonliteral")
return g_strdup_printf (klass->export_path.path,
++(*klass->export_path.int_counter));
NM_PRAGMA_WARNING_REENABLE
}
return g_strdup (klass->export_path.path);
}
/**
* nm_dbus_object_export:
* @self: an #NMDBusObject
*
* Exports @self on all active and future D-Bus connections.
*
* The path to export @self on is taken from its #NMObjectClass's %export_path
* member. If the %export_path contains "%u", then it will be replaced with a
* monotonically increasing integer ID (with each distinct %export_path having
* its own counter). Otherwise, %export_path will be used literally (implying
* that @self must be a singleton).
*
* Returns: the path @self was exported under
*/
const char *
nm_dbus_object_export (NMDBusObject *self)
{
static guint64 id_counter = 0;
g_return_val_if_fail (NM_IS_DBUS_OBJECT (self), NULL);
g_return_val_if_fail (!self->internal.path, self->internal.path);
nm_assert (!self->internal.is_unexporting);
self->internal.path = _create_export_path (NM_DBUS_OBJECT_GET_CLASS (self));
self->internal.export_version_id = ++id_counter;
_LOGT ("export: \"%s\"", self->internal.path);
_nm_dbus_manager_obj_export (self);
_emit_exported_changed (self);
return self->internal.path;
}
/**
* nm_dbus_object_unexport:
* @self: an #NMDBusObject
*
* Unexports @self on all active D-Bus connections (and prevents it from being
* auto-exported on future connections).
*/
void
nm_dbus_object_unexport (NMDBusObject *self)
{
g_return_if_fail (NM_IS_DBUS_OBJECT (self));
g_return_if_fail (self->internal.path);
_LOGT ("unexport: \"%s\"", self->internal.path);
/* note that we emit the signal *before* actually unexporting the object.
* The reason is, that listeners want to use this signal to know that
* the object goes away, and clear their D-Bus path to this object.
*
* But this must happen before we actually unregister the object, so
* that we first emit a D-Bus signal that other objects no longer
* reference this object, before finally unregistering the object itself.
*
* The inconvenient part is, that at this point nm_dbus_object_get_path()
* still returns the path. So, the callee needs to handle that. Possibly
* by using "nm_dbus_object_get_path_still_exported()". */
self->internal.is_unexporting = TRUE;
_emit_exported_changed (self);
_nm_dbus_manager_obj_unexport (self);
nm_clear_g_free (&self->internal.path);
self->internal.export_version_id = 0;
self->internal.is_unexporting = FALSE;
}
/*****************************************************************************/
void
_nm_dbus_object_clear_and_unexport (NMDBusObject **location)
{
NMDBusObject *self;
g_return_if_fail (location);
if (!*location)
return;
self = g_steal_pointer (location);
g_return_if_fail (NM_IS_DBUS_OBJECT (self));
if (self->internal.path)
nm_dbus_object_unexport (self);
g_object_unref (self);
}
/*****************************************************************************/
void
nm_dbus_object_emit_signal_variant (NMDBusObject *self,
const NMDBusInterfaceInfoExtended *interface_info,
const GDBusSignalInfo *signal_info,
GVariant *args)
{
if (!self->internal.path) {
nm_g_variant_unref_floating (args);
return;
}
_nm_dbus_manager_obj_emit_signal (self, interface_info, signal_info, args);
}
void
nm_dbus_object_emit_signal (NMDBusObject *self,
const NMDBusInterfaceInfoExtended *interface_info,
const GDBusSignalInfo *signal_info,
const char *format,
...)
{
va_list ap;
nm_assert (NM_IS_DBUS_OBJECT (self));
nm_assert (format);
if (!self->internal.path)
return;
va_start (ap, format);
_nm_dbus_manager_obj_emit_signal (self,
interface_info,
signal_info,
g_variant_new_va (format, NULL, &ap));
va_end (ap);
}
/*****************************************************************************/
static void
dispatch_properties_changed (GObject *object,
guint n_pspecs,
GParamSpec **pspecs)
{
NMDBusObject *self = NM_DBUS_OBJECT (object);
if (self->internal.path)
_nm_dbus_manager_obj_notify (self, n_pspecs, (const GParamSpec *const*) pspecs);
G_OBJECT_CLASS (nm_dbus_object_parent_class)->dispatch_properties_changed (object, n_pspecs, pspecs);
}
/*****************************************************************************/
static void
nm_dbus_object_init (NMDBusObject *self)
{
c_list_init (&self->internal.objects_lst);
c_list_init (&self->internal.registration_lst_head);
self->internal.bus_manager = nm_g_object_ref (nm_dbus_manager_get ());
}
static void
constructed (GObject *object)
{
NMDBusObjectClass *klass;
G_OBJECT_CLASS (nm_dbus_object_parent_class)->constructed (object);
klass = NM_DBUS_OBJECT_GET_CLASS (object);
if (klass->export_on_construction)
nm_dbus_object_export ((NMDBusObject *) object);
/* NMDBusObject types should be very careful when overwriting notify().
* It is possible to do, but this is a reminder that it's probably not
* a good idea.
*
* It's not a good idea, because NMDBusObject uses dispatch_properties_changed()
* to emit signals about a bunch of property changes. So, we want to make
* use of g_object_freeze_notify() / g_object_thaw_notify() to combine multiple
* property changes in one signal on D-Bus. Note that notify() is not invoked
* while the signal is frozen, that means, whatever you do inside notify()
* will not make it into the same batch of PropertiesChanged signal. That is
* confusing, and probably not what you want.
*
* Simple solution: don't overwrite notify(). */
nm_assert (!G_OBJECT_CLASS (klass)->notify);
}
static void
dispose (GObject *object)
{
NMDBusObject *self = NM_DBUS_OBJECT (object);
/* Objects should have already been unexported by their owner, unless
* we are quitting, where many objects stick around until exit.
*/
if (self->internal.path) {
if (!nm_dbus_manager_is_stopping (nm_dbus_object_get_manager (self)))
g_warn_if_reached ();
nm_dbus_object_unexport (self);
}
G_OBJECT_CLASS (nm_dbus_object_parent_class)->dispose (object);
g_clear_object (&self->internal.bus_manager);
}
static void
nm_dbus_object_class_init (NMDBusObjectClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->constructed = constructed;
object_class->dispose = dispose;
object_class->dispatch_properties_changed = dispatch_properties_changed;
signals[EXPORTED_CHANGED] =
g_signal_new (NM_DBUS_OBJECT_EXPORTED_CHANGED,
G_OBJECT_CLASS_TYPE (object_class),
G_SIGNAL_RUN_FIRST,
0, NULL, NULL,
g_cclosure_marshal_VOID__VOID,
G_TYPE_NONE, 0);
}