scripts: add ubinize-image.sh to generate ubi images

This is a wrapper for the ubinize tool which integrates auto-generation
of the ubinize.cfg for common volume layouts with and without a kernel
volume.
It supports auto-detecting the rootfs-type and decides whether or not
to include a rootfs_data volume based on whether the rootfs is ubifs
or not (and thus is read-only and needs rootfs_data ubifs overlay).
The script allows to create layouts as found in all current
ubinize{,-overlay}.cfg files using

ubinize-image.sh --no-kernel root.{ubifs,squashfs} output.ubi $UBI_OPTS

It also includes support for adding ubootenv and ubootenv2 volumes
typically used by U-Boot for storing its environment in UBI using the
"--uboot-env" parameter.
See also
https://gitorious.org/openwrt-oxnas/openwrt-oxnas/source/target/linux/
oxnas/image/Makefile

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

 create mode 100755 scripts/ubinize-image.sh

SVN-Revision: 41121

scripts/ubinize-image.sh

@@ -0,0 +1,113 @@
+#!/bin/sh
+
+ubootenv=""
+nokernel=""
+ubinize_param=""
+kernel=""
+rootfs=""
+outfile=""
+err=""
+
+get_magic_word() {
+	dd if=$1 bs=2 count=1 2>/dev/null | hexdump -v -n 2 -e '1/1 "%02x"'
+}
+
+is_ubifs() {
+	if [ "$( get_magic_word $1 )" = "3118" ]; then
+		echo "1"
+	fi
+}
+
+ubivol() {
+	volid=$1
+	name=$2
+	image=$3
+	autoresize=$4
+	echo "[$name]"
+	echo "mode=ubi"
+	echo "vol_id=$volid"
+	echo "vol_type=dynamic"
+	echo "vol_name=$name"
+	if [ "$image" ]; then
+		echo "image=$image"
+	else
+		echo "vol_size=1MiB"
+	fi
+	if [ "$autoresize" ]; then
+		echo "vol_flags=autoresize"
+	fi
+}
+
+ubilayout() {
+	local vol_id=0
+	local root_is_ubifs="$( is_ubifs "$2" )"
+	if [ "$1" = "ubootenv" ]; then
+		ubivol $vol_id ubootenv
+		vol_id=$(( $vol_id + 1 ))
+		ubivol $vol_id ubootenv2
+		vol_id=$(( $vol_id + 1 ))
+	fi
+	if [ "$3" ]; then
+		ubivol $vol_id kernel "$3"
+		vol_id=$(( $vol_id + 1 ))
+	fi
+	ubivol $vol_id rootfs "$2" $root_is_ubifs
+	vol_id=$(( $vol_id + 1 ))
+	[ "$root_is_ubifs" ] || ubivol $vol_id rootfs_data "" 1
+}
+
+while [ "$1" ]; do
+	if [ "$1" = "--uboot-env" ]; then
+		ubootenv="ubootenv"
+		shift
+		continue
+	fi
+	if [ "$1" = "--no-kernel" ]; then
+		nokernel="nokernel"
+		shift
+		continue
+	fi
+	if [ ! "$kernel" -a ! "$nokernel" ]; then
+		[ "${1:0:1}" = "-" ] && break
+		kernel=$1
+		shift
+		continue
+	fi
+	if [ ! "$rootfs" ]; then
+		[ "${1:0:1}" = "-" ] && break
+		rootfs=$1
+		shift
+		continue
+	fi
+	if [ ! "$outfile" ]; then
+		[ "${1:0:1}" = "-" ] && break
+		outfile=$1
+		shift
+		continue
+	fi
+	ubinize_param="$@"
+	break
+done
+
+if [ ! -r "$rootfs" -o ! -r "$kernel" -a ! "$nokernel" -o ! "$outfile" ]; then
+	echo "syntax: $0 [--no-kernel] [--uboot-env] rootfs [kernel] out [ubinize opts]"
+	exit 1
+fi
+
+ubinize="$( which ubinize )"
+if [ ! -x "$ubinize" ]; then
+	echo "ubinize tool not found or not usable"
+	exit 1
+fi
+
+ubinizecfg="$( mktemp )"
+ubilayout "$ubootenv" "$rootfs" "$kernel" > "$ubinizecfg"
+
+cat "$ubinizecfg"
+ubinize -o "$outfile" $ubinize_param "$ubinizecfg"
+err="$?"
+[ ! -e "$outfile" ] && err=2
+rm "$ubinizecfg"
+
+exit $err
+