files: add overlayfs-etc-preinit.sh.in

A template init script for overlayfs-etc class

(From OE-Core rev: c0173002f3f2118f72307b7e60515287a1b56bda)

Signed-off-by: Vyacheslav Yurkov <uvv.mail@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/files/overlayfs-etc-preinit.sh.in

@@ -0,0 +1,29 @@
+#!/bin/sh
+
+echo "PREINIT: Start"
+
+PATH=/sbin:/bin:/usr/sbin:/usr/bin
+mount -o remount,rw /
+
+mkdir -p /proc
+mkdir -p /sys
+mkdir -p /run
+mkdir -p /var/run
+
+mount -t proc proc /proc
+mount -t sysfs sysfs /sys
+
+[ -z "$CONSOLE" ] && CONSOLE="/dev/console"
+
+mkdir -p {OVERLAYFS_ETC_MOUNT_POINT}
+if mount -n -t {OVERLAYFS_ETC_FSTYPE} -o {OVERLAYFS_ETC_MOUNT_OPTIONS} {OVERLAYFS_ETC_DEVICE} {OVERLAYFS_ETC_MOUNT_POINT}
+then
+    mkdir -p {OVERLAYFS_ETC_MOUNT_POINT}/overlay-etc/upper
+    mkdir -p {OVERLAYFS_ETC_MOUNT_POINT}/overlay-etc/work
+    mount -n -t overlay -o upperdir={OVERLAYFS_ETC_MOUNT_POINT}/overlay-etc/upper,lowerdir=/etc,workdir={OVERLAYFS_ETC_MOUNT_POINT}/overlay-etc/work {OVERLAYFS_ETC_MOUNT_POINT}/overlay-etc/upper /etc || echo "PREINIT: Mounting etc-overlay failed!"
+else
+    echo "PREINIT: Mounting </data> failed!"
+fi
+
+echo "PREINIT: done; starting </sbin/init>"
+exec {SBIN_INIT_NAME}