openwrtv4/package/base-files/files/etc/preinit

#!/bin/sh
# Copyright (C) 2006 OpenWrt.org
export PATH=/bin:/sbin:/usr/bin:/usr/sbin
. /etc/diag.sh

failsafe() {
	lock /tmp/.failsafe
	ash --login
}

mount none /proc -t proc
mount none /sys  -t sysfs

size=$(awk '/MemTotal:/ {l=5242880;mt=($2*1024);print((s=mt/2)<l)?mt-l:s}' /proc/meminfo)
mount none /tmp -t tmpfs -o size=$size,nosuid,nodev,mode=1777

if grep devfs /proc/filesystems > /dev/null; then
	mount none /dev -t devfs
	M0=/dev/pty/m0
	M1=/dev/pty/m1
	HOTPLUG=/sbin/hotplug-call
else
	mount -t tmpfs tmpfs /dev -o size=512K
	mknod /dev/console c 5 1
	mkdir /dev/shm
	/sbin/hotplug2 --no-persistent --coldplug --set-rules-file /etc/hotplug2-init.rules
	M0=/dev/ptmx
	M1=/dev/ptmx
	HOTPLUG=
fi

mkdir -p /dev/pts /dev/shm
mount none /dev/pts -t devpts

# the shell really doesn't like having stdin/out closed
# that's why we use /dev/pty/m0 and m1 as replacement
# for /dev/console if there's no serial console available
dd if=/dev/console of=/dev/null bs=1 count=0 >/dev/null 2>/dev/null && {
	M0=/dev/console
	M1=/dev/console
}

exec <$M0 >$M1 2>&0

{
	echo "- preinit -"
	[ -e /etc/preinit.arch ] && . /etc/preinit.arch
	set_state preinit

	echo "$HOTPLUG" > /proc/sys/kernel/hotplug

	eval ${FAILSAFE:+failsafe}
	lock -w /tmp/.failsafe

	mount_root

	echo "- init -"
} | tee /tmp/preinit.log

exec /sbin/init