[dhcpc-busybox] Don't wait for dhcp on br0 anymore

We did this to avoid issues if the hostname changes after Xorg
started up. But sometimes, DHCP is really slow, and we delay the
startup of the login screen by a good 10 seconds. Avoid this
by instead just touching the flag file that prevents the udhcpc
trigger script from changing the hostname. Running with a
potentially wrong hostname should be an acceptable tradeoff.

5 files changed, 20 insertions, 27 deletions

diff --git a/core/modules/dhcpc-busybox/data/etc/systemd/system/lightdm.service.d/lock-hostname.conf b/core/modules/dhcpc-busybox/data/etc/systemd/system/lightdm.service.d/lock-hostname.conf
new file mode 100644
index 00000000..cf079a5b
--- /dev/null
+++ b/core/modules/dhcpc-busybox/data/etc/systemd/system/lightdm.service.d/lock-hostname.conf
@@ -0,0 +1,2 @@
+[Service]
+ExecStartPre=-/opt/openslx/scripts/udhcpc-openslx --lock-hostname-updates
diff --git a/core/modules/dhcpc-busybox/data/opt/openslx/scripts/udhcpc-openslx b/core/modules/dhcpc-busybox/data/opt/openslx/scripts/udhcpc-openslx
index 0d74e832..327bdaa4 100755
--- a/core/modules/dhcpc-busybox/data/opt/openslx/scripts/udhcpc-openslx
+++ b/core/modules/dhcpc-busybox/data/opt/openslx/scripts/udhcpc-openslx
@@ -29,6 +29,22 @@ declare -rg RESOLV_CONF="/opt/openslx/resolv.conf"
 declare -rg THIS_RESOLV="/run/network/${interface}.resolv"
 declare -rg flag="/run/network/primary-dhcp.flag"
 
+if [ "$1" = "--lock-hostname-updates" ]; then
+	# If we change the hostname while Xorg is running, this might
+	# cause issues, depending on how it's set up. So we run this
+	# script with the lock argument to touch the flag file right
+	# before we try to launch lightdm/Xorg. In case the DHCP request
+	# is too slow, this means we'll run with the wrong hostname
+	# (potentially), but that's better than delaying the bootup
+	# unnecessarily.
+	# So also note that if you ever change this script's name/location
+	# (JUST DON'T), you'd need to update all call sites, i.e. the
+	# udhcpc startup script, and the lightdm service drop-in.
+	mkdir -p /run/network
+	touch "$flag"
+	exit 0
+fi
+
 shopt -s extglob
 
 rebuild_resolv_conf () {
@@ -186,7 +202,8 @@ case "$1" in
 				echo "SLX_NET_WINS='$wins'" >> /opt/openslx/config
 			fi
 			
-			# Only if network is not ready yet
+			# Only update hostname if network is not ready yet
+			# later on this might cause issues
 			if ! [ -e "$flag" ]; then
 				# Update hostname
 				if [ -z "$dns_fqdn" ] && [ -n "$domain" ] && [ -n "$hostname" ]; then
diff --git a/core/modules/slx-network-configs-targets/data/etc/systemd/system/network.target.wants/slx-wait-primary-dhcp.service b/core/modules/slx-network-configs-targets/data/etc/systemd/system/network.target.wants/slx-wait-primary-dhcp.service
deleted file mode 120000
index e7f32c14..00000000
--- a/core/modules/slx-network-configs-targets/data/etc/systemd/system/network.target.wants/slx-wait-primary-dhcp.service
+++ /dev/null
@@ -1 +0,0 @@
-../slx-wait-primary-dhcp.service
\ No newline at end of file
diff --git a/core/modules/slx-network-configs-targets/data/etc/systemd/system/slx-wait-primary-dhcp.service b/core/modules/slx-network-configs-targets/data/etc/systemd/system/slx-wait-primary-dhcp.service
deleted file mode 100644
index 68dc13f7..00000000
--- a/core/modules/slx-network-configs-targets/data/etc/systemd/system/slx-wait-primary-dhcp.service
+++ /dev/null
@@ -1,7 +0,0 @@
-[Unit]
-Description=Wait until DHCP for the primary NIC has finished
-Before=network.target
-
-[Service]
-Type=oneshot
-ExecStart=/opt/openslx/scripts/systemd-wait_primary_dhcp
diff --git a/core/modules/slx-network-configs-targets/data/opt/openslx/scripts/systemd-wait_primary_dhcp b/core/modules/slx-network-configs-targets/data/opt/openslx/scripts/systemd-wait_primary_dhcp
deleted file mode 100755
index 3e452549..00000000
--- a/core/modules/slx-network-configs-targets/data/opt/openslx/scripts/systemd-wait_primary_dhcp
+++ /dev/null
@@ -1,18 +0,0 @@
-#!/bin/ash
-
-flag="/run/network/primary-dhcp.flag"
-readonly flag
-w=0
-
-# Wait a maximum of 10 seconds for the flag file
-while ! [ -e "$flag" ] && [ "$w" -lt 10 ]; do
-	let w++
-	sleep 1
-done
-
-# Then touch it anyways, this will prevent the DHCP
-# trigger script from changing the hostname later on
-mkdir -p /run/network
-touch "$flag"
-
-exit 0