dbus: merge branch 'th/dbus-utils-cleanup'

https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1454

12 files changed, 290 insertions, 340 deletions

diff --git a/Makefile.am b/Makefile.am
index d75aefae86..7142073cad 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1370,7 +1370,6 @@ src_libnm_core_impl_lib_c_settings_real = \
 src_libnm_core_impl_lib_c_real = \
 	$(src_libnm_core_impl_lib_c_settings_real) \
 	src/libnm-core-impl/nm-connection.c \
-	src/libnm-core-impl/nm-dbus-utils.c \
 	src/libnm-core-impl/nm-errors.c \
 	src/libnm-core-impl/nm-keyfile-utils.c \
 	src/libnm-core-impl/nm-keyfile.c \
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 82895456b0..a1a5730075 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -72,7 +72,6 @@ src/libnm-client-impl/nm-vpn-service-plugin.c
 src/libnm-core-aux-extern/nm-libnm-core-aux.c
 src/libnm-core-aux-intern/nm-libnm-core-utils.c
 src/libnm-core-impl/nm-connection.c
-src/libnm-core-impl/nm-dbus-utils.c
 src/libnm-core-impl/nm-keyfile-utils.c
 src/libnm-core-impl/nm-keyfile.c
 src/libnm-core-impl/nm-setting-6lowpan.c
@@ -132,6 +131,7 @@ src/libnm-crypto/nm-crypto-gnutls.c
 src/libnm-crypto/nm-crypto-nss.c
 src/libnm-crypto/nm-crypto-null.c
 src/libnm-crypto/nm-crypto.c
+src/libnm-glib-aux/nm-dbus-aux.c
 src/libnm-glib-aux/nm-shared-utils.c
 src/libnm-log-core/nm-logging.c
 src/libnmc-base/nm-client-utils.c
diff --git a/src/core/devices/wwan/nm-modem-ofono.c b/src/core/devices/wwan/nm-modem-ofono.c
index 10e6d145b7..b374562189 100644
--- a/src/core/devices/wwan/nm-modem-ofono.c
+++ b/src/core/devices/wwan/nm-modem-ofono.c
@@ -7,6 +7,7 @@
 
 #include "nm-modem-ofono.h"
 
+#include "libnm-glib-aux/nm-dbus-aux.h"
 #include "libnm-core-intern/nm-core-internal.h"
 #include "libnm-glib-aux/nm-uuid.h"
 #include "devices/nm-device-private.h"
@@ -453,11 +454,11 @@ _sim_proxy_new_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     priv->sim_proxy = proxy;
 
     /* Watch for custom ofono PropertyChanged signals */
-    _nm_dbus_signal_connect(priv->sim_proxy,
-                            "PropertyChanged",
-                            G_VARIANT_TYPE("(sv)"),
-                            G_CALLBACK(sim_property_changed),
-                            self);
+    _nm_dbus_proxy_signal_connect(priv->sim_proxy,
+                                  "PropertyChanged",
+                                  G_VARIANT_TYPE("(sv)"),
+                                  G_CALLBACK(sim_property_changed),
+                                  self);
 
     g_dbus_proxy_call(priv->sim_proxy,
                       "GetProperties",
@@ -833,11 +834,11 @@ _context_proxy_new_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     _LOGD("recieved proxy for %s", g_dbus_proxy_get_object_path(proxy));
     octx->proxy = proxy;
 
-    _nm_dbus_signal_connect(proxy,
-                            "PropertyChanged",
-                            G_VARIANT_TYPE("(sv)"),
-                            G_CALLBACK(context_property_changed),
-                            octx);
+    _nm_dbus_proxy_signal_connect(proxy,
+                                  "PropertyChanged",
+                                  G_VARIANT_TYPE("(sv)"),
+                                  G_CALLBACK(context_property_changed),
+                                  octx);
 
     uuid = _generate_uuid(priv->imsi, g_dbus_proxy_get_object_path(proxy));
     g_hash_table_insert(priv->contexts, uuid, octx);
@@ -972,23 +973,23 @@ _connman_proxy_new_cb(GObject *source, GAsyncResult *result, gpointer user_data)
 
     priv->connman_proxy = proxy;
 
-    _nm_dbus_signal_connect(priv->connman_proxy,
-                            "PropertyChanged",
-                            G_VARIANT_TYPE("(sv)"),
-                            G_CALLBACK(connman_property_changed),
-                            self);
+    _nm_dbus_proxy_signal_connect(priv->connman_proxy,
+                                  "PropertyChanged",
+                                  G_VARIANT_TYPE("(sv)"),
+                                  G_CALLBACK(connman_property_changed),
+                                  self);
 
-    _nm_dbus_signal_connect(priv->connman_proxy,
-                            "ContextAdded",
-                            G_VARIANT_TYPE("(oa{sv})"),
-                            G_CALLBACK(connman_context_added),
-                            self);
+    _nm_dbus_proxy_signal_connect(priv->connman_proxy,
+                                  "ContextAdded",
+                                  G_VARIANT_TYPE("(oa{sv})"),
+                                  G_CALLBACK(connman_context_added),
+                                  self);
 
-    _nm_dbus_signal_connect(priv->connman_proxy,
-                            "ContextRemoved",
-                            G_VARIANT_TYPE("(o)"),
-                            G_CALLBACK(connman_context_removed),
-                            self);
+    _nm_dbus_proxy_signal_connect(priv->connman_proxy,
+                                  "ContextRemoved",
+                                  G_VARIANT_TYPE("(o)"),
+                                  G_CALLBACK(connman_context_removed),
+                                  self);
 
     g_dbus_proxy_call(priv->connman_proxy,
                       "GetProperties",
@@ -1575,11 +1576,11 @@ modem_proxy_new_cb(GObject *source, GAsyncResult *result, gpointer user_data)
 
     priv->modem_proxy = proxy;
 
-    _nm_dbus_signal_connect(priv->modem_proxy,
-                            "PropertyChanged",
-                            G_VARIANT_TYPE("(sv)"),
-                            G_CALLBACK(modem_property_changed),
-                            self);
+    _nm_dbus_proxy_signal_connect(priv->modem_proxy,
+                                  "PropertyChanged",
+                                  G_VARIANT_TYPE("(sv)"),
+                                  G_CALLBACK(modem_property_changed),
+                                  self);
 
     g_dbus_proxy_call(priv->modem_proxy,
                       "GetProperties",
diff --git a/src/core/nm-dispatcher.c b/src/core/nm-dispatcher.c
index 1617dc3667..ab361faa7b 100644
--- a/src/core/nm-dispatcher.c
+++ b/src/core/nm-dispatcher.c
@@ -8,6 +8,7 @@
 
 #include "nm-dispatcher.h"
 
+#include "libnm-glib-aux/nm-dbus-aux.h"
 #include "libnm-core-aux-extern/nm-dispatcher-api.h"
 #include "NetworkManagerUtils.h"
 #include "nm-utils.h"
@@ -428,7 +429,7 @@ dispatcher_done_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     if (!ret) {
         NMLogLevel log_level = LOGL_DEBUG;
 
-        if (_nm_dbus_error_has_name(error, "org.freedesktop.systemd1.LoadFailed")) {
+        if (nm_dbus_error_is(error, "org.freedesktop.systemd1.LoadFailed")) {
             g_dbus_error_strip_remote_error(error);
             log_level = LOGL_WARN;
         }
diff --git a/src/core/nm-sleep-monitor.c b/src/core/nm-sleep-monitor.c
index a7ea496de9..66ea2f6c71 100644
--- a/src/core/nm-sleep-monitor.c
+++ b/src/core/nm-sleep-monitor.c
@@ -11,6 +11,7 @@
 #include <sys/stat.h>
 #include <gio/gunixfdlist.h>
 
+#include "libnm-glib-aux/nm-dbus-aux.h"
 #include "libnm-core-intern/nm-core-internal.h"
 #include "NetworkManagerUtils.h"
 
@@ -294,24 +295,24 @@ on_proxy_acquired(GObject *object, GAsyncResult *res, NMSleepMonitor *self)
     g_clear_object(&self->cancellable);
 
 #if USE_UPOWER
-    self->sig_id_1 = _nm_dbus_signal_connect(self->proxy,
-                                             "Sleeping",
-                                             NULL,
-                                             G_CALLBACK(upower_sleeping_cb),
-                                             self);
-    self->sig_id_2 = _nm_dbus_signal_connect(self->proxy,
-                                             "Resuming",
-                                             NULL,
-                                             G_CALLBACK(upower_resuming_cb),
-                                             self);
+    self->sig_id_1 = _nm_dbus_proxy_signal_connect(self->proxy,
+                                                   "Sleeping",
+                                                   NULL,
+                                                   G_CALLBACK(upower_sleeping_cb),
+                                                   self);
+    self->sig_id_2 = _nm_dbus_proxy_signal_connect(self->proxy,
+                                                   "Resuming",
+                                                   NULL,
+                                                   G_CALLBACK(upower_resuming_cb),
+                                                   self);
 #else
     self->sig_id_1 =
         g_signal_connect(self->proxy, "notify::g-name-owner", G_CALLBACK(name_owner_cb), self);
-    self->sig_id_2 = _nm_dbus_signal_connect(self->proxy,
-                                             "PrepareForSleep",
-                                             G_VARIANT_TYPE("(b)"),
-                                             G_CALLBACK(prepare_for_sleep_cb),
-                                             self);
+    self->sig_id_2 = _nm_dbus_proxy_signal_connect(self->proxy,
+                                                   "PrepareForSleep",
+                                                   G_VARIANT_TYPE("(b)"),
+                                                   G_CALLBACK(prepare_for_sleep_cb),
+                                                   self);
     {
         gs_free char *owner = NULL;
 
diff --git a/src/core/supplicant/nm-supplicant-interface.c b/src/core/supplicant/nm-supplicant-interface.c
index 5b5d86229c..18525724f4 100644
--- a/src/core/supplicant/nm-supplicant-interface.c
+++ b/src/core/supplicant/nm-supplicant-interface.c
@@ -2647,7 +2647,7 @@ scan_request_cb(GObject *source, GAsyncResult *result, gpointer user_data)
         _LOGD("request-scan: request cancelled");
     else {
         if (error) {
-            if (_nm_dbus_error_has_name(error, "fi.w1.wpa_supplicant1.Interface.ScanError"))
+            if (nm_dbus_error_is(error, "fi.w1.wpa_supplicant1.Interface.ScanError"))
                 _LOGD("request-scan: could not get scan request result: %s", error->message);
             else {
                 g_dbus_error_strip_remote_error(error);
diff --git a/src/core/supplicant/nm-supplicant-manager.c b/src/core/supplicant/nm-supplicant-manager.c
index 2ec7db237a..f6927500dd 100644
--- a/src/core/supplicant/nm-supplicant-manager.c
+++ b/src/core/supplicant/nm-supplicant-manager.c
@@ -450,7 +450,7 @@ _create_iface_dbus_call_get_interface_cb(GObject *source, GAsyncResult *result,
         char ifname[NMP_IFNAMSIZ];
 
         if (handle->create_iface_try_count < CREATE_IFACE_TRY_COUNT_MAX
-            && _nm_dbus_error_has_name(error, NM_WPAS_ERROR_UNKNOWN_IFACE)
+            && nm_dbus_error_is(error, NM_WPAS_ERROR_UNKNOWN_IFACE)
             && nm_platform_if_indextoname(NM_PLATFORM_GET, handle->ifindex, ifname)) {
             /* Before, supplicant told us the interface existed. Was there a race?
              * Try again. */
@@ -500,7 +500,7 @@ _create_iface_dbus_call_create_interface_cb(GObject      *source,
                 nm_assert(handle->self);
                 TRUE;
             })
-            && _nm_dbus_error_has_name(error, NM_WPAS_ERROR_EXISTS_ERROR)
+            && nm_dbus_error_is(error, NM_WPAS_ERROR_EXISTS_ERROR)
             && nm_platform_if_indextoname(NM_PLATFORM_GET, handle->ifindex, ifname)) {
             self = handle->self;
             _LOGT("create-iface[" NM_HASH_OBFUSCATE_PTR_FMT
diff --git a/src/libnm-core-impl/meson.build b/src/libnm-core-impl/meson.build
index 2de3ff0849..25d4c6b859 100644
--- a/src/libnm-core-impl/meson.build
+++ b/src/libnm-core-impl/meson.build
@@ -60,7 +60,6 @@ libnm_core_settings_sources = files(
 
 libnm_core_impl_sources = files(
   'nm-connection.c',
-  'nm-dbus-utils.c',
   'nm-errors.c',
   'nm-keyfile-utils.c',
   'nm-keyfile.c',
diff --git a/src/libnm-core-impl/nm-dbus-utils.c b/src/libnm-core-impl/nm-dbus-utils.c
deleted file mode 100644
index c9443ff944..0000000000
--- a/src/libnm-core-impl/nm-dbus-utils.c
+++ /dev/null
@@ -1,259 +0,0 @@
-/* SPDX-License-Identifier: LGPL-2.1-or-later */
-/*
- * Copyright (C) 2015 Red Hat, Inc.
- */
-
-#include "libnm-core-impl/nm-default-libnm-core.h"
-
-#include "libnm-core-intern/nm-core-internal.h"
-
-typedef struct {
-    char               *signal_name;
-    const GVariantType *signature;
-} NMDBusSignalData;
-
-static void
-dbus_signal_data_free(gpointer data, GClosure *closure)
-{
-    NMDBusSignalData *sd = data;
-
-    g_free(sd->signal_name);
-    g_slice_free(NMDBusSignalData, sd);
-}
-
-static void
-dbus_signal_meta_marshal(GClosure     *closure,
-                         GValue       *return_value,
-                         guint         n_param_values,
-                         const GValue *param_values,
-                         gpointer      invocation_hint,
-                         gpointer      marshal_data)
-{
-    NMDBusSignalData *sd = marshal_data;
-    const char       *signal_name;
-    GVariant         *parameters, *param;
-    GValue           *closure_params;
-    gsize             n_params, i;
-
-    g_return_if_fail(n_param_values == 4);
-
-    signal_name = g_value_get_string(&param_values[2]);
-    parameters  = g_value_get_variant(&param_values[3]);
-
-    if (strcmp(signal_name, sd->signal_name) != 0)
-        return;
-
-    if (sd->signature) {
-        if (!g_variant_is_of_type(parameters, sd->signature)) {
-            g_warning("%p: got signal '%s' but parameters were of type '%s', not '%s'",
-                      g_value_get_object(&param_values[0]),
-                      signal_name,
-                      g_variant_get_type_string(parameters),
-                      g_variant_type_peek_string(sd->signature));
-            return;
-        }
-
-        n_params = g_variant_n_children(parameters) + 1;
-    } else
-        n_params = 1;
-
-    closure_params = g_new0(GValue, n_params);
-    g_value_init(&closure_params[0], G_TYPE_OBJECT);
-    g_value_copy(&param_values[0], &closure_params[0]);
-
-    for (i = 1; i < n_params; i++) {
-        param = g_variant_get_child_value(parameters, i - 1);
-        if (g_variant_is_of_type(param, G_VARIANT_TYPE("ay"))
-            || g_variant_is_of_type(param, G_VARIANT_TYPE("aay"))) {
-            /* g_dbus_gvariant_to_gvalue() thinks 'ay' means "non-UTF-8 NUL-terminated string" */
-            g_value_init(&closure_params[i], G_TYPE_VARIANT);
-            g_value_set_variant(&closure_params[i], param);
-        } else
-            g_dbus_gvariant_to_gvalue(param, &closure_params[i]);
-        g_variant_unref(param);
-    }
-
-    g_cclosure_marshal_generic(closure, NULL, n_params, closure_params, invocation_hint, NULL);
-
-    for (i = 0; i < n_params; i++)
-        g_value_unset(&closure_params[i]);
-    g_free(closure_params);
-}
-
-/**
- * _nm_dbus_signal_connect_data:
- * @proxy: a #GDBusProxy
- * @signal_name: the D-Bus signal to connect to
- * @signature: (allow-none): the signal's type signature (must be a tuple)
- * @c_handler: the signal handler function
- * @data: (allow-none): data to pass to @c_handler
- * @destroy_data: (allow-none): closure destroy notify for @data
- * @connect_flags: connection flags
- *
- * Connects to the D-Bus signal @signal_name on @proxy. @c_handler must be a
- * void function whose first argument is a #GDBusProxy, followed by arguments
- * for each element of @signature, ending with a #gpointer argument for @data.
- *
- * The argument types in @c_handler correspond to the types output by
- * g_dbus_gvariant_to_gvalue(), except for 'ay' and 'aay'. In particular:
- * - both 16-bit and 32-bit integers are passed as #int/#guint
- * - 'as' values are passed as #GStrv (char **)
- * - all other array, tuple, and dict types are passed as #GVariant
- *
- * If @signature is %NULL, then the signal's parameters will be ignored, and
- * @c_handler should take only the #GDBusProxy and #gpointer arguments.
- *
- * Returns: the signal handler ID, which can be used with
- *   g_signal_handler_remove(). Beware that because of the way the signal is
- *   connected, you will not be able to remove it with
- *   g_signal_handlers_disconnect_by_func(), although
- *   g_signal_handlers_disconnect_by_data() will work correctly.
- */
-gulong
-_nm_dbus_signal_connect_data(GDBusProxy         *proxy,
-                             const char         *signal_name,
-                             const GVariantType *signature,
-                             GCallback           c_handler,
-                             gpointer            data,
-                             GClosureNotify      destroy_data,
-                             GConnectFlags       connect_flags)
-{
-    NMDBusSignalData *sd;
-    GClosure         *closure;
-    gboolean          swapped = !!(connect_flags & G_CONNECT_SWAPPED);
-    gboolean          after   = !!(connect_flags & G_CONNECT_AFTER);
-
-    g_return_val_if_fail(G_IS_DBUS_PROXY(proxy), 0);
-    g_return_val_if_fail(signal_name != NULL, 0);
-    g_return_val_if_fail(signature == NULL || g_variant_type_is_tuple(signature), 0);
-    g_return_val_if_fail(c_handler != NULL, 0);
-
-    sd              = g_slice_new(NMDBusSignalData);
-    sd->signal_name = g_strdup(signal_name);
-    sd->signature   = signature;
-
-    closure = (swapped ? g_cclosure_new_swap : g_cclosure_new)(c_handler, data, destroy_data);
-    g_closure_set_marshal(closure, g_cclosure_marshal_generic);
-    g_closure_set_meta_marshal(closure, sd, dbus_signal_meta_marshal);
-    g_closure_add_finalize_notifier(closure, sd, dbus_signal_data_free);
-
-    return g_signal_connect_closure(proxy, "g-signal", closure, after);
-}
-
-/**
- * _nm_dbus_signal_connect:
- * @proxy: a #GDBusProxy
- * @signal_name: the D-Bus signal to connect to
- * @signature: the signal's type signature (must be a tuple)
- * @c_handler: the signal handler function
- * @data: (allow-none): data to pass to @c_handler
- *
- * Simplified version of _nm_dbus_signal_connect_data() with fewer arguments.
- *
- * Returns: the signal handler ID, as with _nm_signal_connect_data().
- */
-
-/**
- * _nm_dbus_typecheck_response:
- * @response: the #GVariant response to check.
- * @reply_type: the expected reply type. It may be %NULL to perform no
- *   checking.
- * @error: (allow-none): the error in case the @reply_type does not match.
- *
- * Returns: %TRUE, if @response is of the expected @reply_type.
- */
-gboolean
-_nm_dbus_typecheck_response(GVariant *response, const GVariantType *reply_type, GError **error)
-{
-    g_return_val_if_fail(response, FALSE);
-
-    if (!reply_type)
-        return TRUE;
-    if (g_variant_is_of_type(response, reply_type))
-        return TRUE;
-
-    /* This is the same error code that g_dbus_connection_call() returns if
-     * @reply_type doesn't match.
-     */
-    g_set_error(error,
-                G_IO_ERROR,
-                G_IO_ERROR_INVALID_ARGUMENT,
-                _("Method returned type '%s', but expected '%s'"),
-                g_variant_get_type_string(response),
-                g_variant_type_peek_string(reply_type));
-    return FALSE;
-}
-
-/**
- * _nm_dbus_proxy_call_finish:
- * @proxy: A #GDBusProxy.
- * @res: A #GAsyncResult obtained from the #GAsyncReadyCallback passed to
- *   g_dbus_proxy_call().
- * @reply_type: (allow-none): the expected type of the reply, or %NULL
- * @error: Return location for error or %NULL.
- *
- * Finishes an operation started with g_dbus_proxy_call(), as with
- * g_dbus_proxy_call_finish(), except thatif @reply_type is non-%NULL, then it
- * will also check that the response matches that type signature, and return
- * an error if not.
- *
- * Returns: %NULL if @error is set. Otherwise, a #GVariant tuple with
- * return values. Free with g_variant_unref().
- */
-GVariant *
-_nm_dbus_proxy_call_finish(GDBusProxy         *proxy,
-                           GAsyncResult       *res,
-                           const GVariantType *reply_type,
-                           GError            **error)
-{
-    GVariant *variant;
-
-    variant = g_dbus_proxy_call_finish(proxy, res, error);
-    if (variant && !_nm_dbus_typecheck_response(variant, reply_type, error))
-        nm_clear_pointer(&variant, g_variant_unref);
-    return variant;
-}
-
-GVariant *
-_nm_dbus_connection_call_finish(GDBusConnection    *dbus_connection,
-                                GAsyncResult       *result,
-                                const GVariantType *reply_type,
-                                GError            **error)
-{
-    GVariant *variant;
-
-    variant = g_dbus_connection_call_finish(dbus_connection, result, error);
-    if (variant && !_nm_dbus_typecheck_response(variant, reply_type, error))
-        nm_clear_pointer(&variant, g_variant_unref);
-    return variant;
-}
-
-/**
- * _nm_dbus_error_has_name:
- * @error: (allow-none): a #GError, or %NULL
- * @dbus_error_name: a D-Bus error name
- *
- * Checks if @error is set and corresponds to the D-Bus error @dbus_error_name.
- *
- * This should only be used for "foreign" D-Bus errors (eg, errors
- * from BlueZ or wpa_supplicant). All NetworkManager D-Bus errors
- * should be properly mapped by gdbus to one of the domains/codes in
- * nm-errors.h.
- *
- * Returns: %TRUE or %FALSE
- */
-gboolean
-_nm_dbus_error_has_name(GError *error, const char *dbus_error_name)
-{
-    gboolean has_name = FALSE;
-
-    if (error && g_dbus_error_is_remote_error(error)) {
-        char *error_name;
-
-        error_name = g_dbus_error_get_remote_error(error);
-        has_name   = !g_strcmp0(error_name, dbus_error_name);
-        g_free(error_name);
-    }
-
-    return has_name;
-}
diff --git a/src/libnm-core-intern/nm-core-internal.h b/src/libnm-core-intern/nm-core-internal.h
index 21c994f033..df9a6d047b 100644
--- a/src/libnm-core-intern/nm-core-internal.h
+++ b/src/libnm-core-intern/nm-core-internal.h
@@ -367,31 +367,6 @@ void _nm_dbus_errors_init(void);
 
 extern gboolean _nm_utils_is_manager_process;
 
-gboolean
-_nm_dbus_typecheck_response(GVariant *response, const GVariantType *reply_type, GError **error);
-
-gulong _nm_dbus_signal_connect_data(GDBusProxy         *proxy,
-                                    const char         *signal_name,
-                                    const GVariantType *signature,
-                                    GCallback           c_handler,
-                                    gpointer            data,
-                                    GClosureNotify      destroy_data,
-                                    GConnectFlags       connect_flags);
-#define _nm_dbus_signal_connect(proxy, name, signature, handler, data) \
-    _nm_dbus_signal_connect_data(proxy, name, signature, handler, data, NULL, (GConnectFlags) 0)
-
-GVariant *_nm_dbus_proxy_call_finish(GDBusProxy         *proxy,
-                                     GAsyncResult       *res,
-                                     const GVariantType *reply_type,
-                                     GError            **error);
-
-GVariant *_nm_dbus_connection_call_finish(GDBusConnection    *dbus_connection,
-                                          GAsyncResult       *result,
-                                          const GVariantType *reply_type,
-                                          GError            **error);
-
-gboolean _nm_dbus_error_has_name(GError *error, const char *dbus_error_name);
-
 /*****************************************************************************/
 
 char *_nm_utils_ssid_to_utf8(GBytes *ssid);
diff --git a/src/libnm-glib-aux/nm-dbus-aux.c b/src/libnm-glib-aux/nm-dbus-aux.c
index c6597aea5a..3925da55bc 100644
--- a/src/libnm-glib-aux/nm-dbus-aux.c
+++ b/src/libnm-glib-aux/nm-dbus-aux.c
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 /*
- * Copyright (C) 2019 Red Hat, Inc.
+ * Copyright (C) 2015,2019 Red Hat, Inc.
  */
 
 #include "libnm-glib-aux/nm-default-glib-i18n-lib.h"
@@ -414,6 +414,12 @@ _nm_dbus_error_is(GError *error, ...)
     gs_free char *dbus_error = NULL;
     const char   *name;
     va_list       ap;
+    gboolean      found = FALSE;
+
+    /* This should only be used for "foreign" D-Bus errors (eg, errors
+     * from BlueZ or wpa_supplicant). All NetworkManager D-Bus errors
+     * should be properly mapped by gdbus to one of the domains/codes in
+     * nm-errors.h. */
 
     dbus_error = g_dbus_error_get_remote_error(error);
     if (!dbus_error)
@@ -422,13 +428,13 @@ _nm_dbus_error_is(GError *error, ...)
     va_start(ap, error);
     while ((name = va_arg(ap, const char *))) {
         if (nm_streq(dbus_error, name)) {
-            va_end(ap);
-            return TRUE;
+            found = TRUE;
+            break;
         }
     }
     va_end(ap);
 
-    return FALSE;
+    return found;
 }
 
 /*****************************************************************************/
@@ -517,3 +523,194 @@ nm_dbus_connection_call_blocking(NMDBusConnectionCallBlockingData *data, GError
 
     return g_steal_pointer(&result);
 }
+
+/*****************************************************************************/
+
+typedef struct {
+    char               *signal_name;
+    const GVariantType *signature;
+} NMDBusSignalData;
+
+static void
+dbus_signal_data_free(gpointer data, GClosure *closure)
+{
+    NMDBusSignalData *sd = data;
+
+    g_free(sd->signal_name);
+    g_slice_free(NMDBusSignalData, sd);
+}
+
+static void
+dbus_signal_meta_marshal(GClosure     *closure,
+                         GValue       *return_value,
+                         guint         n_param_values,
+                         const GValue *param_values,
+                         gpointer      invocation_hint,
+                         gpointer      marshal_data)
+{
+    NMDBusSignalData *sd = marshal_data;
+    const char       *signal_name;
+    GVariant         *parameters;
+    gs_free GValue   *closure_params_free = NULL;
+    GValue           *closure_params;
+    gsize             n_params;
+    gsize             i;
+
+    g_return_if_fail(n_param_values == 4);
+
+    signal_name = g_value_get_string(&param_values[2]);
+    parameters  = g_value_get_variant(&param_values[3]);
+
+    if (!nm_streq(signal_name, sd->signal_name))
+        return;
+
+    if (sd->signature) {
+        if (!g_variant_is_of_type(parameters, sd->signature)) {
+            g_warning("%p: got signal '%s' but parameters were of type '%s', not '%s'",
+                      g_value_get_object(&param_values[0]),
+                      signal_name,
+                      g_variant_get_type_string(parameters),
+                      g_variant_type_peek_string(sd->signature));
+            return;
+        }
+
+        n_params = g_variant_n_children(parameters) + 1;
+    } else
+        n_params = 1;
+
+    closure_params = nm_malloc0_maybe_a(240, sizeof(GValue) * n_params, &closure_params_free);
+    g_value_init(&closure_params[0], G_TYPE_OBJECT);
+    g_value_copy(&param_values[0], &closure_params[0]);
+
+    for (i = 1; i < n_params; i++) {
+        gs_unref_variant GVariant *param = NULL;
+
+        param = g_variant_get_child_value(parameters, i - 1);
+        if (g_variant_is_of_type(param, G_VARIANT_TYPE("ay"))
+            || g_variant_is_of_type(param, G_VARIANT_TYPE("aay"))) {
+            /* g_dbus_gvariant_to_gvalue() thinks 'ay' means "non-UTF-8 NUL-terminated string" */
+            g_value_init(&closure_params[i], G_TYPE_VARIANT);
+            g_value_set_variant(&closure_params[i], param);
+        } else
+            g_dbus_gvariant_to_gvalue(param, &closure_params[i]);
+    }
+
+    g_cclosure_marshal_generic(closure, NULL, n_params, closure_params, invocation_hint, NULL);
+
+    for (i = 0; i < n_params; i++)
+        g_value_unset(&closure_params[i]);
+}
+
+/**
+ * _nm_dbus_proxy_signal_connect_data:
+ * @proxy: a #GDBusProxy
+ * @signal_name: the D-Bus signal to connect to
+ * @signature: (allow-none): the signal's type signature (must be a tuple)
+ * @c_handler: the signal handler function
+ * @data: (allow-none): data to pass to @c_handler
+ * @destroy_data: (allow-none): closure destroy notify for @data
+ * @connect_flags: connection flags
+ *
+ * Connects to the D-Bus signal @signal_name on @proxy. @c_handler must be a
+ * void function whose first argument is a #GDBusProxy, followed by arguments
+ * for each element of @signature, ending with a #gpointer argument for @data.
+ *
+ * The argument types in @c_handler correspond to the types output by
+ * g_dbus_gvariant_to_gvalue(), except for 'ay' and 'aay'. In particular:
+ * - both 16-bit and 32-bit integers are passed as #int/#guint
+ * - 'as' values are passed as #GStrv (char **)
+ * - all other array, tuple, and dict types are passed as #GVariant
+ *
+ * If @signature is %NULL, then the signal's parameters will be ignored, and
+ * @c_handler should take only the #GDBusProxy and #gpointer arguments.
+ *
+ * Returns: the signal handler ID, which can be used with
+ *   g_signal_handler_remove(). Beware that because of the way the signal is
+ *   connected, you will not be able to remove it with
+ *   g_signal_handlers_disconnect_by_func(), although
+ *   g_signal_handlers_disconnect_by_data() will work correctly.
+ */
+gulong
+_nm_dbus_proxy_signal_connect_data(GDBusProxy         *proxy,
+                                   const char         *signal_name,
+                                   const GVariantType *signature,
+                                   GCallback           c_handler,
+                                   gpointer            data,
+                                   GClosureNotify      destroy_data,
+                                   GConnectFlags       connect_flags)
+{
+    NMDBusSignalData *sd;
+    GClosure         *closure;
+    gboolean          swapped = !!(connect_flags & G_CONNECT_SWAPPED);
+    gboolean          after   = !!(connect_flags & G_CONNECT_AFTER);
+
+    g_return_val_if_fail(G_IS_DBUS_PROXY(proxy), 0);
+    g_return_val_if_fail(signal_name != NULL, 0);
+    g_return_val_if_fail(signature == NULL || g_variant_type_is_tuple(signature), 0);
+    g_return_val_if_fail(c_handler != NULL, 0);
+
+    sd              = g_slice_new(NMDBusSignalData);
+    sd->signal_name = g_strdup(signal_name);
+    sd->signature   = signature;
+
+    closure = (swapped ? g_cclosure_new_swap : g_cclosure_new)(c_handler, data, destroy_data);
+    g_closure_set_marshal(closure, g_cclosure_marshal_generic);
+    g_closure_set_meta_marshal(closure, sd, dbus_signal_meta_marshal);
+    g_closure_add_finalize_notifier(closure, sd, dbus_signal_data_free);
+
+    return g_signal_connect_closure(proxy, "g-signal", closure, after);
+}
+
+/*****************************************************************************/
+
+static gboolean
+_nm_dbus_typecheck_response(GVariant *response, const GVariantType *reply_type, GError **error)
+{
+    g_return_val_if_fail(response, FALSE);
+
+    if (!reply_type)
+        return TRUE;
+    if (g_variant_is_of_type(response, reply_type))
+        return TRUE;
+
+    /* This is the same error code that g_dbus_connection_call() returns if
+     * @reply_type doesn't match.
+     */
+    g_set_error(error,
+                G_IO_ERROR,
+                G_IO_ERROR_INVALID_ARGUMENT,
+                _("Method returned type '%s', but expected '%s'"),
+                g_variant_get_type_string(response),
+                g_variant_type_peek_string(reply_type));
+    return FALSE;
+}
+
+/**
+ * _nm_dbus_proxy_call_finish:
+ * @proxy: A #GDBusProxy.
+ * @res: A #GAsyncResult obtained from the #GAsyncReadyCallback passed to
+ *   g_dbus_proxy_call().
+ * @reply_type: (allow-none): the expected type of the reply, or %NULL
+ * @error: Return location for error or %NULL.
+ *
+ * Finishes an operation started with g_dbus_proxy_call(), as with
+ * g_dbus_proxy_call_finish(), except thatif @reply_type is non-%NULL, then it
+ * will also check that the response matches that type signature, and return
+ * an error if not.
+ *
+ * Returns: %NULL if @error is set. Otherwise, a #GVariant tuple with
+ * return values. Free with g_variant_unref().
+ */
+GVariant *
+_nm_dbus_proxy_call_finish(GDBusProxy         *proxy,
+                           GAsyncResult       *res,
+                           const GVariantType *reply_type,
+                           GError            **error)
+{
+    GVariant *variant;
+
+    variant = g_dbus_proxy_call_finish(proxy, res, error);
+    if (variant && !_nm_dbus_typecheck_response(variant, reply_type, error))
+        nm_clear_pointer(&variant, g_variant_unref);
+    return variant;
+}
diff --git a/src/libnm-glib-aux/nm-dbus-aux.h b/src/libnm-glib-aux/nm-dbus-aux.h
index b7cb0b8da4..5db79c08f7 100644
--- a/src/libnm-glib-aux/nm-dbus-aux.h
+++ b/src/libnm-glib-aux/nm-dbus-aux.h
@@ -274,4 +274,40 @@ nm_g_variant_tuple_get_u(GVariant *v, guint32 *out_u)
     return FALSE;
 }
 
+/*****************************************************************************/
+
+gulong _nm_dbus_proxy_signal_connect_data(GDBusProxy         *proxy,
+                                          const char         *signal_name,
+                                          const GVariantType *signature,
+                                          GCallback           c_handler,
+                                          gpointer            data,
+                                          GClosureNotify      destroy_data,
+                                          GConnectFlags       connect_flags);
+
+/**
+ * _nm_dbus_proxy_signal_connect:
+ * @proxy: a #GDBusProxy
+ * @signal_name: the D-Bus signal to connect to
+ * @signature: the signal's type signature (must be a tuple)
+ * @c_handler: the signal handler function
+ * @data: (allow-none): data to pass to @c_handler
+ *
+ * Simplified version of _nm_dbus_proxy_signal_connect_data() with fewer arguments.
+ *
+ * Returns: the signal handler ID, as with _nm_signal_connect_data().
+ */
+#define _nm_dbus_proxy_signal_connect(proxy, name, signature, handler, data) \
+    _nm_dbus_proxy_signal_connect_data(proxy,                                \
+                                       name,                                 \
+                                       signature,                            \
+                                       handler,                              \
+                                       data,                                 \
+                                       NULL,                                 \
+                                       (GConnectFlags) 0)
+
+GVariant *_nm_dbus_proxy_call_finish(GDBusProxy         *proxy,
+                                     GAsyncResult       *res,
+                                     const GVariantType *reply_type,
+                                     GError            **error);
+
 #endif /* __NM_DBUS_AUX_H__ */