libnm: add out_is_modified argument to from_dbus_fcn() to detect modification

Note that most implementations use g_object_set(), and it's not
easy to detect modification. In those cases, we assume that modification
happened -- just like also the GObject setter will emit a notification
(as none of our properties use G_PARAM_EXPLICIT_NOTIFY).

src/libnm-core-impl/nm-setting-ip-config.c

@@ -5024,6 +5024,7 @@ _routing_rules_dbus_only_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     success = TRUE;
 
 out:
+    *out_is_modified = rules_changed;
     if (rules_changed)
         _routing_rules_notify(NM_SETTING_IP_CONFIG(setting));
     return success;
@@ -5760,6 +5761,7 @@ _nm_setting_property_from_dbus_fcn_direct_ip_config_gateway(
                                                      connection_dict,
                                                      value,
                                                      parse_flags,
+                                                     out_is_modified,
                                                      error);
 }
 

src/libnm-core-impl/nm-setting-ip4-config.c

@@ -361,8 +361,10 @@ ip4_addresses_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 
     /* FIXME: properly handle errors */
 
-    if (!_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data"))
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     addrs = nm_utils_ip4_addresses_from_variant(value, &gateway);
 
@@ -449,8 +451,10 @@ ip4_address_data_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     /* FIXME: properly handle errors */
 
     /* Ignore 'address-data' if we're going to process 'addresses' */
-    if (_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data"))
+    if (_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     addrs = nm_utils_ip_addresses_from_variant(value, AF_INET);
     g_object_set(setting, NM_SETTING_IP_CONFIG_ADDRESSES, addrs, NULL);
@@ -474,8 +478,10 @@ ip4_routes_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 
     /* FIXME: properly handle errors */
 
-    if (!_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data"))
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     routes = nm_utils_ip4_routes_from_variant(value);
     g_object_set(setting, property_info->name, routes, NULL);
@@ -503,8 +509,10 @@ ip4_route_data_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     /* FIXME: properly handle errors */
 
     /* Ignore 'route-data' if we're going to process 'routes' */
-    if (_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data"))
+    if (_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     routes = nm_utils_ip_routes_from_variant(value, AF_INET);
     g_object_set(setting, NM_SETTING_IP_CONFIG_ROUTES, routes, NULL);

src/libnm-core-impl/nm-setting-ip6-config.c

@@ -398,10 +398,10 @@ ip6_addresses_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     GPtrArray *addrs;
     char *     gateway = NULL;
 
-    /* FIXME: properly handle errors */
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data")) {
-
+        *out_is_modified = FALSE;
-    if (!_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data"))
         return TRUE;
+    }
 
     addrs = nm_utils_ip6_addresses_from_variant(value, &gateway);
 
@@ -433,11 +433,11 @@ ip6_address_data_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
     GPtrArray *addrs;
 
-    /* FIXME: properly handle errors */
-
     /* Ignore 'address-data' if we're going to process 'addresses' */
-    if (_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data"))
+    if (_nm_setting_use_legacy_property(setting, connection_dict, "addresses", "address-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     addrs = nm_utils_ip_addresses_from_variant(value, AF_INET6);
     g_object_set(setting, NM_SETTING_IP_CONFIG_ADDRESSES, addrs, NULL);
@@ -459,10 +459,10 @@ ip6_routes_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
     GPtrArray *routes;
 
-    /* FIXME: properly handle errors */
+    if (!_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data")) {
-
+        *out_is_modified = FALSE;
-    if (!_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data"))
         return TRUE;
+    }
 
     routes = nm_utils_ip6_routes_from_variant(value);
     g_object_set(setting, property_info->name, routes, NULL);
@@ -487,11 +487,11 @@ ip6_route_data_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
     GPtrArray *routes;
 
-    /* FIXME: properly handle errors */
-
     /* Ignore 'route-data' if we're going to process 'routes' */
-    if (_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data"))
+    if (_nm_setting_use_legacy_property(setting, connection_dict, "routes", "route-data")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     routes = nm_utils_ip_routes_from_variant(value, AF_INET6);
     g_object_set(setting, NM_SETTING_IP_CONFIG_ROUTES, routes, NULL);

src/libnm-core-impl/nm-setting-tc-config.c

@@ -1486,12 +1486,10 @@ tc_qdiscs_get(_NM_SETT_INFO_PROP_TO_DBUS_FCN_ARGS _nm_nil)
 static gboolean
 tc_qdiscs_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
-    GPtrArray *qdiscs;
+    gs_unref_ptrarray GPtrArray *qdiscs = NULL;
 
     qdiscs = _qdiscs_from_variant(value);
     g_object_set(setting, NM_SETTING_TC_CONFIG_QDISCS, qdiscs, NULL);
-    g_ptr_array_unref(qdiscs);
-
     return TRUE;
 }
 

src/libnm-core-impl/nm-setting-wireguard.c

@@ -1677,6 +1677,7 @@ _peers_dbus_only_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     success = TRUE;
 
 out:
+    *out_is_modified = peers_changed;
     if (peers_changed)
         _peers_notify(setting);
     return success;

src/libnm-core-impl/nm-setting-wireless.c

@@ -771,6 +771,7 @@ _from_dbus_fcn_seen_bssids(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     if (_nm_utils_is_manager_process) {
         /* in the manager process, we don't accept seen-bssid from the client.
          * Do nothing.  */
+        *out_is_modified = FALSE;
         return TRUE;
     }
 

src/libnm-core-impl/nm-setting.c

@@ -1071,6 +1071,7 @@ _nm_setting_property_to_dbus_fcn_gprop(_NM_SETT_INFO_PROP_TO_DBUS_FCN_ARGS _nm_n
 gboolean
 _nm_setting_property_from_dbus_fcn_ignore(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
 {
+    *out_is_modified = FALSE;
     return TRUE;
 }
 
@@ -1091,8 +1092,10 @@ _nm_setting_property_from_dbus_fcn_direct_mac_address(_NM_SETT_INFO_PROP_FROM_DB
 
     if (nm_strdup_reset_take(
             _nm_setting_get_private(setting, sett_info, property_info->direct_offset),
-            length > 0 ? nm_utils_hwaddr_ntoa(array, length) : NULL))
+            length > 0 ? nm_utils_hwaddr_ntoa(array, length) : NULL)) {
         g_object_notify_by_pspec(G_OBJECT(setting), property_info->param_spec);
+    } else
+        *out_is_modified = FALSE;
 
     return TRUE;
 }
@@ -1125,6 +1128,8 @@ _nm_setting_property_from_dbus_fcn_direct(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS
         _success;                                                                      \
     })
 
+    *out_is_modified = FALSE;
+
     switch (property_info->property_type->direct_type) {
     case NM_VALUE_TYPE_BOOL:
     {
@@ -1239,6 +1244,7 @@ out_unchanged:
     return TRUE;
 
 out_notify:
+    *out_is_modified = TRUE;
     g_object_notify_by_pspec(G_OBJECT(setting), property_info->param_spec);
     return TRUE;
 
@@ -1282,6 +1288,7 @@ _nm_setting_property_from_dbus_fcn_gprop(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _
     g_value_init(&object_value, property_info->param_spec->value_type);
     if (!set_property_from_dbus(property_info, value, &object_value)) {
         /* for backward behavior, fail unless best-effort is chosen. */
+        *out_is_modified = FALSE;
         if (NM_FLAGS_HAS(parse_flags, NM_SETTING_PARSE_FLAGS_BEST_EFFORT))
             return TRUE;
         g_set_error(error,
@@ -1302,6 +1309,7 @@ _nm_setting_property_from_dbus_fcn_gprop(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _
                                   property_info->param_spec->name,
                                   &object_value,
                                   &local)) {
+        *out_is_modified = FALSE;
         if (!NM_FLAGS_HAS(parse_flags, NM_SETTING_PARSE_FLAGS_STRICT))
             return TRUE;
         g_set_error(error,
@@ -1567,9 +1575,14 @@ _property_set_from_dbus(const NMSettInfoSetting * sett_info,
                         GVariant *                connection_dict,
                         GVariant *                value,
                         NMSettingParseFlags       parse_flags,
+                        gboolean *                out_is_modified,
                         GError **                 error)
 {
     gs_free_error GError *local       = NULL;
+    NMTernary             is_modified = NM_TERNARY_DEFAULT;
+    gboolean              success;
+
+    NM_SET_OUT(out_is_modified, FALSE);
 
     if (!property_info->property_type->from_dbus_fcn) {
         nm_assert(!property_info->param_spec);
@@ -1597,13 +1610,21 @@ _property_set_from_dbus(const NMSettInfoSetting * sett_info,
         return FALSE;
     }
 
-    if (!property_info->property_type->from_dbus_fcn(sett_info,
+    success = property_info->property_type->from_dbus_fcn(sett_info,
                                                           property_info,
                                                           setting,
                                                           connection_dict,
                                                           value,
                                                           parse_flags,
-                                                     &local)) {
+                                                          &is_modified,
+                                                          &local);
+
+    /* We allow the from_dbus_fcn() to leave is_modified at NM_TERNARY_DEFAULT,
+     * which we assume to also mean that it was modified. That is, we err on the
+     * side of assuming modification happened. */
+    NM_SET_OUT(out_is_modified, is_modified != FALSE);
+
+    if (!success) {
         if (property_info->property_type->from_dbus_is_full) {
             /* the error we received from from_dbus_fcn() should be propagated, even
              * in non-strict mode. */
@@ -1711,6 +1732,7 @@ init_from_dbus(NMSetting *                     setting,
                                      connection_dict,
                                      value,
                                      parse_flags,
+                                     NULL,
                                      error))
             return FALSE;
     }

src/libnm-core-impl/nm-utils.c

@@ -4084,14 +4084,18 @@ _nm_utils_hwaddr_cloned_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     if (!_nm_setting_use_legacy_property(setting,
                                          connection_dict,
                                          "cloned-mac-address",
-                                         "assigned-mac-address"))
+                                         "assigned-mac-address")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     length = 0;
     array  = g_variant_get_fixed_array(value, &length, 1);
 
-    if (!length)
+    if (!length) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     str = nm_utils_hwaddr_ntoa(array, length);
     g_object_set(setting, "cloned-mac-address", str, NULL);
@@ -4143,8 +4147,10 @@ _nm_utils_hwaddr_cloned_data_set(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil)
     if (_nm_setting_use_legacy_property(setting,
                                         connection_dict,
                                         "cloned-mac-address",
-                                        "assigned-mac-address"))
+                                        "assigned-mac-address")) {
+        *out_is_modified = FALSE;
         return TRUE;
+    }
 
     g_object_set(setting,
                  "cloned-mac-address",

src/libnm-core-intern/nm-core-internal.h

@@ -716,7 +716,7 @@ typedef struct {
 #define _NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS                                    \
     const NMSettInfoSetting *sett_info, const NMSettInfoProperty *property_info, \
         NMSetting *setting, GVariant *connection_dict, GVariant *value,          \
-        NMSettingParseFlags parse_flags, GError **error
+        NMSettingParseFlags parse_flags, NMTernary *out_is_modified, GError **error
 
     gboolean (*from_dbus_fcn)(_NM_SETT_INFO_PROP_FROM_DBUS_FCN_ARGS _nm_nil);