abuild/initramfs-init

#!/bin/busybox sh

# this is the init script version
VERSION=1.1
NEWROOT=/newroot
SINGLEMODE=no

/bin/busybox --install -s

# basic environment
export PATH=/usr/bin:/bin:/usr/sbin:/sbin

# needed devs
[ -c /dev/null ] || mknod -m 666 /dev/null c 1 3

# basic mounts
mount -t proc -o noexec,nosuid,nodev proc /proc
mount -t sysfs -o noexec,nosuid,nodev sysfs /sys

# some helpers
ebegin() {
	echo -n " * $*: "
}
eend() {
	local msg
	if [ "$1" = 0 ] || [ $# -lt 1 ] ; then
		echo "ok."
	else
		shift
		echo "failed. $*"
		echo "initramfs emergency recovery shell launched. Type 'exit' to continue boot"
		/bin/busybox sh
	fi
}

scan_drivers() {
	if [ "$AUTODETECT" != no ] ; then
		find /sys -name modalias | xargs sort -u | xargs modprobe -a 2> /dev/null
	fi
}

find_ovl() {
	local mnt="$1"
	local ovl
	local lines

	# look for apkovl's on mounted media
	ovl=$( ls -1 "$mnt"/*.apkovl.tar.gz* 2>/dev/null ) || return 1
	lines=$(echo "$ovl" | wc -l)

	if [ $lines -gt 1 ] ; then
		echo "ERROR: More than one apkovl file was found on $(basename $mnt). None will be read." >&2
		return 1
	fi
	echo "$ovl"
}

retry_mount() {
	# usb might need some time to settle so we retry a few times
	for i in $(seq 0 19); do
		mount $@ 2>&1 && return 0
		sleep 1
	done
	return 1
}

unpack_apkovl() {
	local ovl="$1"
	local dest="$2"
	local suffix=${ovl##*.}
	local i
	if [ "$suffix" = "gz" ]; then
		tar -C "$dest" -zxf "$ovl"
		return $?
	fi

	for i in $ALPINE_MNT/*/*/openssl-[0-9]*.apk $ALPINE_MNT/*/openssl-[0-9]*.apk; do
		[ -f "$i" ] && tar --numeric-owner -C / -zxf $i && break
	done

	if ! openssl list-cipher-commands | grep "^$suffix$" > /dev/null; then
		errstr="Cipher $suffix is not supported"
		return 1
	fi
	local count=0
	# beep
	echo -e "\007"
	while [ $count -lt 3 ]; do
		openssl enc -d -$suffix -in "$ovl" | tar --numeric-owner \
			-C "$dest" -zx 2>/dev/null && return 0
		count=$(( $count + 1 ))
	done
	return 1
}

# gotta start from somewhere :)
echo "Alpine Init $VERSION"

# read the kernel options
for i in `cat /proc/cmdline` ; do
	case $i in
		s|single|1)
			SINGLEMODE=yes ;;
		modules=*)
			MODULES="`echo ${i#modules=} | tr ',' ' '`";;
		noautodetect)
			AUTODETECT=no;;
		*=*)    eval KOPT_$i ;;
		*)      eval KOPT_$i=yes ;;
	esac
done

# start bootcharting if wanted
if [ -n "$KOPT_chart" ]; then
	ebegin "Starting bootchart logging"
	/sbin/bootchartd start-initfs "$NEWROOT"
	eend 0
fi

ALPINE_DEV=${KOPT_alpine_dev%%:*}
ALPINE_DEV_FS=${KOPT_alpine_dev##*:}
if [ "$ALPINE_DEV_FS" = "$ALPINE_DEV" ]; then
	unset ALPINE_DEV_FS
fi
ALPINE_MNT=/media/$ALPINE_DEV

# hide kernel messages
dmesg -n 1

# setup /dev
ebegin "Starting mdev"
mount -t tmpfs -o exec,nosuid,mode=0755 mdev /dev
ln -s sr0 /dev/cdrom
echo "/sbin/mdev" > /proc/sys/kernel/hotplug
mdev -s
RC=$?
[ -d /dev/pts ] || mkdir -m 755 /dev/pts
[ -c /dev/ptmx ] || mknod -m 666 /dev/ptmx c 5 2
mount -t devpts -o gid=5,mode=0620,noexec,nosuid devpts /dev/pts
[ -d /dev/shm ] || mkdir /dev/shm
mount -t tmpfs -o nodev,nosuid,noexec shm /dev/shm
eend $RC

# load available drivers to get access to modloop media
ebegin "Loading boot drivers"
[ "$MODULES" ] && modprobe -a $MODULES 2> /dev/null
if [ -f /etc/modules ] ; then
	sed 's/\#.*//g' < /etc/modules |
	while read module args; do
		modprobe -q $module $args
	done
fi
scan_drivers
scan_drivers
eend 0

# check if root=... was set
if [ -n "$KOPT_root" ]; then
	if [ "$SINGLEMODE" = "yes" ]; then
		echo "Entering single mode. Type 'exit' to continue booting."
		sh
	fi
	case "$KOPT_root" in
		/dev/md*) 
			mknod $KOPT_root b 9 ${KOPT_root#/dev/md}
			raidautorun "$KOPT_root"
			;;
	esac
	ebegin "Mounting root"
	retry_mount $KOPT_root $NEWROOT 2>/dev/null
	eend $?
	cat /proc/mounts | while read DEV DIR TYPE OPTS ; do
		if [ "$DIR" != "/" -a "$DIR" != "$NEWROOT" -a -d "$DIR" ]; then
			mkdir -p $NEWROOT/$DIR
			mount -o move $DIR $NEWROOT/$DIR
		fi
	done
	sync
	exec /bin/busybox switch_root $NEWROOT $chart_init /sbin/init $KOPT_init_args
	echo "initramfs emergency recovery shell launched"
	exec /bin/busybox sh
fi

# locate boot media and mount it
ebegin "Mounting boot media"
mkdir -p $ALPINE_MNT
if [ -n "$ALPINE_DEV_FS" ]; then
	mount_opts="-t $ALPINE_DEV_FS"
fi

retry_mount $mount_opts /dev/$ALPINE_DEV $ALPINE_MNT >/dev/null 2>&1
eend $?

ebegin "Mounting loopback device for kernel modules"
modprobe loop
if [ -n "$KOPT_modloop" ]; then
	modloop=$KOPT_modloop
else
	modloop=$KOPT_BOOT_IMAGE.cmg
fi
mount -o loop,ro -t cramfs $ALPINE_MNT/$modloop /.modloop
rc=$?
if [ "$rc" = 0 ]; then
	rm -rf /lib/modules
	ln -sf /.modloop/modules /lib
fi
eend $?

if [ -d $ALPINE_MNT/firmware ]; then
	ebegin "Copying firmware from $ALPINE_MNT/firmware"
	mkdir -p /lib
	cp -R -a $ALPINE_MNT/firmware /lib/
	eend $?
fi

mkdir -p /etc/apk
for i in $ALPINE_MNT/*/APK_INDEX.gz $ALPINE_MNT/*/*/APK_INDEX.gz; do
	[ -r "$i" ] && echo ${i%/APK_INDEX.gz} >> /etc/apk/repositories
done

# early console?
if [ "$SINGLEMODE" = "yes" ]; then
	echo "Entering single mode. Type 'exit' to continue booting."
	sh
fi

# more drivers
ebegin "Loading hardware drivers"
scan_drivers
eend 0

mount -t tmpfs tmpfs $NEWROOT

# look for apkovl
if dmesg | grep '^usb-storage: waiting' >/dev/null; then
	ebegin "Waiting for USB device to settle"
	while ! dmesg | grep 'usb-storage: device scan complete' >/dev/null; do
		sleep 1
	done
	eend 0
fi
for i in usb floppy cdrom; do
	mount /media/$i 2>/dev/null || continue
	ovl=$(find_ovl /media/$i)
	[ -f "$ovl" ] && break
	umount /media/$i 2>/dev/null
done
if ! [ -f "$ovl" ]; then
	ovl=$(find_ovl $ALPINE_MNT)
fi

if [ -f "$ovl" ]; then
	ebegin "Loading user settings from $ovl"
	unpack_apkovl "$ovl" $NEWROOT
	eend $? $errstr
	umount /media/$i 2>/dev/null &
	pkgs=$(sed 's/\#.*//' $NEWROOT/etc/lbu/packages.list 2>/dev/null)
fi

# install new root
ebegin "Installing packages to root filesystem"
if [ -n "$KOPT_chart" ]; then
	pkgs="$pkgs acct"
fi
apkflags="--initdb --quiet --progress --force"
if [ -z "$KOPT_keep_apk_new" ]; then
	apkflags="$apkflags --clean-protected"
fi
apk add --root /newroot $apkflags $pkgs >/dev/null
eend $?

# copy alpine release info
cp $ALPINE_MNT/.alpine-release $NEWROOT/
ln -sf /.alpine-release $NEWROOT/etc/alpine-release

# if there is no repositories file, then use the default
if ! [ -f $NEWROOT/etc/apk/repositories ]; then
	cp /etc/apk/repositories $NEWROOT/etc/apk/repositories
fi

# setup bootchart for switch_root
chart_init=""
if [ -n "$KOPT_chart" ]; then
	/sbin/bootchartd stop-initfs "$NEWROOT"
	chart_init="/sbin/bootchartd start-rootfs"
fi

# switch over to new root
cat /proc/mounts | while read DEV DIR TYPE OPTS ; do
	if [ "$DIR" != "/" -a "$DIR" != "$NEWROOT" -a -d "$DIR" ]; then
		mkdir -p $NEWROOT/$DIR
		mount -o move $DIR $NEWROOT/$DIR
	fi
done
ln -sf /.modloop/modules $NEWROOT/lib/modules
sync

echo ""
if [ -x $NEWROOT/sbin/init ]; then
	exec /bin/busybox switch_root $NEWROOT $chart_init /sbin/init $KOPT_init_args
fi

echo "initramfs emergency recovery shell launched"
exec /bin/busybox sh
reboot