feat(image): add overlay to /etc and use busybox getty for login prompt

image/mkimage.sh

@@ -13,6 +13,7 @@ find rootfs/ -type d -exec chmod 755 {} \;
 ln -sf multi-user.target rootfs/usr/lib/systemd/system/default.target
 
 # mount patos state
+ln -sf ../etc.mount rootfs/usr/lib/systemd/system/local-fs.target.wants/etc.mount
 ln -sf ../var.mount rootfs/usr/lib/systemd/system/sysinit.target.wants/var.mount
 
 # enable dbus
@@ -25,32 +26,6 @@ ln -sf ../systemd-networkd.service rootfs/usr/lib/systemd/system/sysinit.target.
 # generate a temporary machine id
 $systemd/usr/bin/systemd-machine-id-setup --root=rootfs/
 
-# FIXME: remove this later (just to get a shell in the initramfs)
-cat <<EOF > rootfs/usr/lib/systemd/system/demo.service
-[Unit]
-Description=Debug Shell (/bin/sulogin)
-Conflicts=shutdown.target
-Before=shutdown.target
-
-[Service]
-Environment=HOME=/root
-WorkingDirectory=/root
-ExecStart=/bin/sulogin
-Type=idle
-StandardInput=tty-force
-StandardOutput=inherit
-StandardError=inherit
-KillMode=process
-IgnoreSIGPIPE=no
-SendSIGHUP=yes
-Restart=always
-
-[Install]
-WantedBy=multi-user.target
-EOF
-ln -sf ../demo.service rootfs/usr/lib/systemd/system/multi-user.target.wants/demo.service
-
-
 $systemd/usr/bin/ukify build \
   --linux $kernel/bzImage \
   --initrd $initrd/initrd.xz \

rootfs/mkrootfs.sh

@@ -1,7 +1,7 @@
 set -ex -o pipefail
 
 mkdir -p $out
-mkdir -p $out/etc/repart.d $out/dev $out/proc $out/sys $out/tmp $out/root $out/run $out/boot $out/mnt
+mkdir -p $out/etc/repart.d $out/dev $out/proc $out/sys $out/tmp $out/root $out/run $out/boot $out/mnt $out/home $out/srv
 ln -sf ../usr/bin $out/bin
 ln -sf ../usr/bin $out/sbin
 ln -sf ../usr/lib $out/lib
@@ -29,6 +29,9 @@ VERSION_ID={version}
 BUILD_ID={version}
 EOF
 
+# replace agetty with busybox getty
+sed -i 's#ExecStart=.*#ExecStart=-/sbin/getty -L %I 115200 vt100#' $out/usr/lib/systemd/system/serial-getty@.service
+
 sed -i 's#After=\(.*\)#After=sysroot.mount \1#' $out/usr/lib/systemd/system/systemd-repart.service
 cat <<EOF > $out/etc/repart.d/10-esp.conf
 [Partition]
@@ -68,6 +71,21 @@ Options=defaults
 WantedBy=multi-user.target
 EOF
 
+cat <<EOF > $out/usr/lib/systemd/system/etc.mount
+[Unit]
+Description=Overlay mount for /etc
+Before=local-fs.target
+
+[Mount]
+What=overlay
+Where=/etc
+Type=overlay
+Options=lowerdir=/etc,upperdir=/run/.rw-etc/upper,workdir=/run/.rw-etc/work
+
+[Install]
+WantedBy=local-fs.target
+EOF
+
 ### install PatOS glibc
 cp -P $glibcPatos/lib/*.so* $out/usr/lib/