device: don't let subclasses call NMDevice's act_stage1_prepare()

NMDevice's act_stage1_prepare() now does nothing. Calling it is not
useful and has no effect.

In general, when a subclass overwrites a virtual function, it must be
defined whether the subclass must, may or must-not call the parents
implementation. Likewise, it must be clear when the parents
implementation should be chained: first, as last, does it matter?
In any case, that very much depends on how the parent is implemented
and this can only be solved by documentation and common conventions.

It's a forgiving approach to have a parents implementation do nothing,
then the subclass may call it at any time (or not call it at all).
This is especially useful if classes don't know their parent class well.
But in NetworkManager code the relationship between classes are known
at compile time, so every of these classes knows it derives directly
from NMDevice.

This forgingin approach was what NMDevice's act_stage1_prepare() was doing.
However, it also adds lines of code resulting in a different kind of complexity.
So, it's not clear that this forgiving approach is really better. Note
that it also has a (tiny) runtime and code-size overhead.

Change the expectation of how NMDevice's act_stage1_prepare() should be
called: it is no longer implemented, and subclasses *MUST* not chain up.

19 files changed, 13 insertions, 109 deletions

diff --git a/src/devices/nm-device-6lowpan.c b/src/devices/nm-device-6lowpan.c
index 7a27943139..b63d0745c9 100644
--- a/src/devices/nm-device-6lowpan.c
+++ b/src/devices/nm-device-6lowpan.c
@@ -233,12 +233,6 @@ update_connection (NMDevice *device, NMConnection *connection)
 static NMActStageReturn
 act_stage1_prepare (NMDevice *dev, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_6lowpan_parent_class)->act_stage1_prepare (dev, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!nm_device_hw_addr_set_cloned (dev, nm_device_get_applied_connection (dev), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
 	return NM_ACT_STAGE_RETURN_SUCCESS;
diff --git a/src/devices/nm-device-bond.c b/src/devices/nm-device-bond.c
index e67941d8f3..1a5a430dbe 100644
--- a/src/devices/nm-device-bond.c
+++ b/src/devices/nm-device-bond.c
@@ -343,10 +343,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 	NMDeviceBond *self = NM_DEVICE_BOND (device);
 	NMActStageReturn ret = NM_ACT_STAGE_RETURN_SUCCESS;
 
-	ret = NM_DEVICE_CLASS (nm_device_bond_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	/* Interface must be down to set bond options */
 	nm_device_take_down (device, TRUE);
 	if (!apply_bonding_config (self))
diff --git a/src/devices/nm-device-bridge.c b/src/devices/nm-device-bridge.c
index 86eaa6e88c..438f850315 100644
--- a/src/devices/nm-device-bridge.c
+++ b/src/devices/nm-device-bridge.c
@@ -497,15 +497,10 @@ bridge_set_vlan_options (NMDevice *device, NMSettingBridge *s_bridge)
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
 	NMConnection *connection;
 	NMSetting *s_bridge;
 	const Option *option;
 
-	ret = NM_DEVICE_CLASS (nm_device_bridge_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	connection = nm_device_get_applied_connection (device);
 	g_return_val_if_fail (connection, NM_ACT_STAGE_RETURN_FAILURE);
 
diff --git a/src/devices/nm-device-dummy.c b/src/devices/nm-device-dummy.c
index 9c0c30358a..75e8f742b6 100644
--- a/src/devices/nm-device-dummy.c
+++ b/src/devices/nm-device-dummy.c
@@ -119,12 +119,6 @@ create_and_realize (NMDevice *device,
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_dummy_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!nm_device_hw_addr_set_cloned (device, nm_device_get_applied_connection (device), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
 
diff --git a/src/devices/nm-device-ethernet.c b/src/devices/nm-device-ethernet.c
index 70531d814d..d5fd155181 100644
--- a/src/devices/nm-device-ethernet.c
+++ b/src/devices/nm-device-ethernet.c
@@ -861,11 +861,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceEthernet *self = NM_DEVICE_ETHERNET (device);
 	NMDeviceEthernetPrivate *priv = NM_DEVICE_ETHERNET_GET_PRIVATE (self);
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_ethernet_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
 
 	link_negotiation_set (device);
 
diff --git a/src/devices/nm-device-infiniband.c b/src/devices/nm-device-infiniband.c
index 18b4d64a3f..ca098d2e12 100644
--- a/src/devices/nm-device-infiniband.c
+++ b/src/devices/nm-device-infiniband.c
@@ -76,16 +76,11 @@ static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	nm_auto_close int dirfd = -1;
-	NMActStageReturn ret;
 	NMSettingInfiniband *s_infiniband;
 	char ifname_verified[IFNAMSIZ];
 	const char *transport_mode;
 	gboolean ok;
 
-	ret = NM_DEVICE_CLASS (nm_device_infiniband_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	s_infiniband = nm_device_get_applied_setting (device, NM_TYPE_SETTING_INFINIBAND);
 
 	g_return_val_if_fail (s_infiniband, NM_ACT_STAGE_RETURN_FAILURE);
diff --git a/src/devices/nm-device-ip-tunnel.c b/src/devices/nm-device-ip-tunnel.c
index ede4487e3a..a490ea4cd2 100644
--- a/src/devices/nm-device-ip-tunnel.c
+++ b/src/devices/nm-device-ip-tunnel.c
@@ -968,12 +968,6 @@ set_property (GObject *object, guint prop_id,
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_ip_tunnel_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!nm_device_hw_addr_set_cloned (device, nm_device_get_applied_connection (device), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
 
diff --git a/src/devices/nm-device-macvlan.c b/src/devices/nm-device-macvlan.c
index ee8b997460..0a4635a852 100644
--- a/src/devices/nm-device-macvlan.c
+++ b/src/devices/nm-device-macvlan.c
@@ -418,12 +418,6 @@ update_connection (NMDevice *device, NMConnection *connection)
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_macvlan_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!nm_device_hw_addr_set_cloned (device, nm_device_get_applied_connection (device), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
 
diff --git a/src/devices/nm-device-tun.c b/src/devices/nm-device-tun.c
index 50099248b9..6d2a03036a 100644
--- a/src/devices/nm-device-tun.c
+++ b/src/devices/nm-device-tun.c
@@ -351,11 +351,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceTun *self = NM_DEVICE_TUN (device);
 	NMDeviceTunPrivate *priv = NM_DEVICE_TUN_GET_PRIVATE (self);
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_tun_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
 
 	if (priv->props.type == IFF_TUN) {
 		/* Nothing to do for TUN devices */
diff --git a/src/devices/nm-device-vlan.c b/src/devices/nm-device-vlan.c
index 27611499c9..616565de9c 100644
--- a/src/devices/nm-device-vlan.c
+++ b/src/devices/nm-device-vlan.c
@@ -477,11 +477,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDevice *parent_device;
 	NMSettingVlan *s_vlan;
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_vlan_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
 
 	if (!nm_device_hw_addr_set_cloned (device, nm_device_get_applied_connection (device), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
diff --git a/src/devices/nm-device-vxlan.c b/src/devices/nm-device-vxlan.c
index 1a700ba459..b2ccd247c2 100644
--- a/src/devices/nm-device-vxlan.c
+++ b/src/devices/nm-device-vxlan.c
@@ -484,12 +484,6 @@ update_connection (NMDevice *device, NMConnection *connection)
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
-
-	ret = NM_DEVICE_CLASS (nm_device_vxlan_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!nm_device_hw_addr_set_cloned (device, nm_device_get_applied_connection (device), FALSE))
 		return NM_ACT_STAGE_RETURN_FAILURE;
 
diff --git a/src/devices/nm-device-wpan.c b/src/devices/nm-device-wpan.c
index 89301f3757..dc6b0e3b93 100644
--- a/src/devices/nm-device-wpan.c
+++ b/src/devices/nm-device-wpan.c
@@ -131,10 +131,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 	NMDevice *lowpan_device = NULL;
 	NMActStageReturn ret = NM_ACT_STAGE_RETURN_FAILURE;
 
-	ret = NM_DEVICE_CLASS (nm_device_wpan_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	platform = nm_device_get_platform (device);
 	nm_assert (NM_IS_PLATFORM (platform));
 
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c
index cbaeb81a88..084ba776ed 100644
--- a/src/devices/nm-device.c
+++ b/src/devices/nm-device.c
@@ -6449,12 +6449,6 @@ sriov_params_cb (GError *error, gpointer data)
 	nm_device_activate_schedule_stage1_device_prepare (self);
 }
 
-static NMActStageReturn
-act_stage1_prepare (NMDevice *self, NMDeviceStateReason *out_failure_reason)
-{
-	return NM_ACT_STAGE_RETURN_SUCCESS;
-}
-
 /*
  * activate_stage1_device_prepare
  *
@@ -6540,17 +6534,21 @@ activate_stage1_device_prepare (NMDevice *self)
 
 	/* Assumed connections were already set up outside NetworkManager */
 	if (!nm_device_sys_iface_state_is_external_or_assume (self)) {
-		NMDeviceStateReason failure_reason = NM_DEVICE_STATE_REASON_NONE;
+		NMDeviceClass *klass = NM_DEVICE_GET_CLASS (self);
 
-		ret = NM_DEVICE_GET_CLASS (self)->act_stage1_prepare (self, &failure_reason);
-		if (ret == NM_ACT_STAGE_RETURN_FAILURE) {
-			nm_device_state_changed (self, NM_DEVICE_STATE_FAILED, failure_reason);
-			return;
-		}
-		if (ret == NM_ACT_STAGE_RETURN_POSTPONE)
-			return;
+		if (klass->act_stage1_prepare) {
+			NMDeviceStateReason failure_reason = NM_DEVICE_STATE_REASON_NONE;
+
+			ret = klass->act_stage1_prepare (self, &failure_reason);
+			if (ret == NM_ACT_STAGE_RETURN_FAILURE) {
+				nm_device_state_changed (self, NM_DEVICE_STATE_FAILED, failure_reason);
+				return;
+			}
+			if (ret == NM_ACT_STAGE_RETURN_POSTPONE)
+				return;
 
-		nm_assert (ret == NM_ACT_STAGE_RETURN_SUCCESS);
+			nm_assert (ret == NM_ACT_STAGE_RETURN_SUCCESS);
+		}
 	}
 
 	nm_device_activate_schedule_stage2_device_config (self);
@@ -17179,7 +17177,6 @@ nm_device_class_init (NMDeviceClass *klass)
 	klass->link_changed = link_changed;
 
 	klass->is_available = is_available;
-	klass->act_stage1_prepare = act_stage1_prepare;
 	klass->act_stage2_config = act_stage2_config;
 	klass->act_stage3_ip_config_start = act_stage3_ip_config_start;
 	klass->act_stage4_ip_config_timeout = act_stage4_ip_config_timeout;
diff --git a/src/devices/team/nm-device-team.c b/src/devices/team/nm-device-team.c
index fb176ed13e..73e288bac5 100644
--- a/src/devices/team/nm-device-team.c
+++ b/src/devices/team/nm-device-team.c
@@ -637,16 +637,11 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceTeam *self = NM_DEVICE_TEAM (device);
 	NMDeviceTeamPrivate *priv = NM_DEVICE_TEAM_GET_PRIVATE (self);
-	NMActStageReturn ret = NM_ACT_STAGE_RETURN_SUCCESS;
 	gs_free_error GError *error = NULL;
 	NMSettingTeam *s_team;
 	NMConnection *connection;
 	const char *cfg;
 
-	ret = NM_DEVICE_CLASS (nm_device_team_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	connection = nm_device_get_applied_connection (device);
 	g_return_val_if_fail (connection, NM_ACT_STAGE_RETURN_FAILURE);
 
diff --git a/src/devices/wifi/nm-device-iwd.c b/src/devices/wifi/nm-device-iwd.c
index b97f439125..1b42aa9dd2 100644
--- a/src/devices/wifi/nm-device-iwd.c
+++ b/src/devices/wifi/nm-device-iwd.c
@@ -1714,7 +1714,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceIwd *self = NM_DEVICE_IWD (device);
 	NMDeviceIwdPrivate *priv = NM_DEVICE_IWD_GET_PRIVATE (self);
-	NMActStageReturn ret;
 	NMWifiAP *ap = NULL;
 	gs_unref_object NMWifiAP *ap_fake = NULL;
 	NMActRequest *req;
@@ -1723,10 +1722,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 	const char *mode;
 	const char *ap_path;
 
-	ret = NM_DEVICE_CLASS (nm_device_iwd_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	req = nm_device_get_act_request (device);
 	g_return_val_if_fail (req, NM_ACT_STAGE_RETURN_FAILURE);
 
diff --git a/src/devices/wifi/nm-device-olpc-mesh.c b/src/devices/wifi/nm-device-olpc-mesh.c
index 3c865c5576..0a89e5a671 100644
--- a/src/devices/wifi/nm-device-olpc-mesh.c
+++ b/src/devices/wifi/nm-device-olpc-mesh.c
@@ -145,13 +145,8 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceOlpcMesh *self = NM_DEVICE_OLPC_MESH (device);
 	NMDeviceOlpcMeshPrivate *priv = NM_DEVICE_OLPC_MESH_GET_PRIVATE (self);
-	NMActStageReturn ret;
 	gboolean scanning;
 
-	ret = NM_DEVICE_CLASS (nm_device_olpc_mesh_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	/* disconnect companion device, if it is connected */
 	if (nm_device_get_act_request (NM_DEVICE (priv->companion))) {
 		_LOGI (LOGD_OLPC, "disconnecting companion device %s",
diff --git a/src/devices/wifi/nm-device-wifi-p2p.c b/src/devices/wifi/nm-device-wifi-p2p.c
index 4bfd3094fc..ef6df10243 100644
--- a/src/devices/wifi/nm-device-wifi-p2p.c
+++ b/src/devices/wifi/nm-device-wifi-p2p.c
@@ -368,15 +368,10 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceWifiP2P *self = NM_DEVICE_WIFI_P2P (device);
 	NMDeviceWifiP2PPrivate *priv = NM_DEVICE_WIFI_P2P_GET_PRIVATE (self);
-	NMActStageReturn ret;
 	NMConnection *connection;
 	NMSettingWifiP2P *s_wifi_p2p;
 	NMWifiP2PPeer *peer;
 
-	ret = NM_DEVICE_CLASS (nm_device_wifi_p2p_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	if (!priv->mgmt_iface) {
 		NM_SET_OUT (out_failure_reason, NM_DEVICE_STATE_REASON_SUPPLICANT_FAILED);
 		return NM_ACT_STAGE_RETURN_FAILURE;
diff --git a/src/devices/wifi/nm-device-wifi.c b/src/devices/wifi/nm-device-wifi.c
index 521d9e3c78..901cb0a542 100644
--- a/src/devices/wifi/nm-device-wifi.c
+++ b/src/devices/wifi/nm-device-wifi.c
@@ -2621,7 +2621,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
 	NMDeviceWifi *self = NM_DEVICE_WIFI (device);
 	NMDeviceWifiPrivate *priv = NM_DEVICE_WIFI_GET_PRIVATE (self);
-	NMActStageReturn ret;
 	NMWifiAP *ap = NULL;
 	gs_unref_object NMWifiAP *ap_fake = NULL;
 	NMActRequest *req;
@@ -2630,10 +2629,6 @@ act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 	const char *mode;
 	const char *ap_path;
 
-	ret = NM_DEVICE_CLASS (nm_device_wifi_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	req = nm_device_get_act_request (NM_DEVICE (self));
 	g_return_val_if_fail (req, NM_ACT_STAGE_RETURN_FAILURE);
 
diff --git a/src/devices/wwan/nm-device-modem.c b/src/devices/wwan/nm-device-modem.c
index 29c51162d0..be0993916d 100644
--- a/src/devices/wwan/nm-device-modem.c
+++ b/src/devices/wwan/nm-device-modem.c
@@ -583,13 +583,8 @@ deactivate_async (NMDevice *self,
 static NMActStageReturn
 act_stage1_prepare (NMDevice *device, NMDeviceStateReason *out_failure_reason)
 {
-	NMActStageReturn ret;
 	NMActRequest *req;
 
-	ret = NM_DEVICE_CLASS (nm_device_modem_parent_class)->act_stage1_prepare (device, out_failure_reason);
-	if (ret != NM_ACT_STAGE_RETURN_SUCCESS)
-		return ret;
-
 	req = nm_device_get_act_request (device);
 	g_return_val_if_fail (req, NM_ACT_STAGE_RETURN_FAILURE);