overlay_convert_and_validate

#! /bin/bash

# Copyright 2016  Frank Rowand  frowand.list@gmail.com
# Copyright 2017  Frank Rowand  frowand.list@gmail.com
#
# license: GPL V2
# This file is subject to the terms and conditions of the GNU General Public
# License v2.
#
# Convert overlay dts file from hand-coded expanded form to new syntactic
# sugar form.  Wrapper around overlay_convert_raw to add some validation.


#_______________________________________________________________________________


function usage
{
echo ""                                                                      >&2
echo "usage:"                                                                >&2
echo "  `basename $0` -h | -help | --help"                                   >&2
echo "  `basename $0` [options] OLD_DTS NEW_DTS"                             >&2
echo ""                                                                      >&2
echo "  Convert OLD_DTS from old overlay style to new overlay style"         >&2
echo "  using syntactic sugar."                                              >&2
echo ""                                                                      >&2
echo "  Wrapper around overlay_convert_raw to add some validation."          >&2
echo ""                                                                      >&2
echo "  Options:"                                                            >&2
echo "     -h               Synonym for --help"                              >&2
echo "    --force           Try to produce output even if errors exist"      >&2
echo "    --help            Print this message"                              >&2
echo "    --no-indent-fix   do not remove extra leading tabs"                >&2
echo "    --overwrite       Overwrite NEW_DTS if it already exists"          >&2
echo "    --verbose         Print more information"                          >&2
echo ""                                                                      >&2
echo "  The early patches to dtc to support overlays required 'fragment'"    >&2
echo "  and '__overlay__' nodes in the .dts source.  Later patches to dtc"   >&2
echo "  will not require these nodes (and may possibly disallow them)."      >&2
echo "  The new overlay style is expected to be the preferrred form."        >&2
echo ""                                                                      >&2
echo "  Will not overwrite NEW_DTS if it already exists."                    >&2
echo ""                                                                      >&2
echo "  Exit status is:"                                                     >&2
echo "    0 success"                                                         >&2
echo "    1 general error"                                                   >&2
echo "    2 NEW_DTS already exists"                                          >&2
echo "    3 conversion ERROR"                                                >&2
echo "    4 conversion WARNING"                                              >&2
echo "    5 'dtc -@ -O dts OLD_DTS' is different than 'dtc -@ -O dts NEW_DTS'" >&2
echo ""                                                                      >&2
echo "    If a conversion WARNING occurs, a diff of OLD_DTS and NEW_DTS"     >&2
echo "    will be attempted.  If the diff succeeds, the exit status will"    >&2
echo "    be 4, else the exit status will be 5."                             >&2
echo ""                                                                      >&2
}


unset force
unset new_dts
unset no_indent_fix
unset old_dts
unset overwrite
unset verbose

while [[ ($# -gt 0) ]] ; do

	case $1 in

		--force )
			shift
			force="--force"
			;;

		-h | -help | --help )
			shift
			help=1
			;;

		--no-indent-fix )
			shift
			no_indent_fix="--no-indent-fix"
			;;

		--overwrite )
			shift
			overwrite=1
			;;

		--verbose )
			shift
			verbose="--verbose"
			;;

		* )
			if [[ "${old_dts}" != "" ]] ; then

				if [[ "${new_dts}" != "" ]] ; then
					echo ""                              >&2
					echo "ERROR: too many arguments"     >&2
					echo ""                              >&2
					exit 1
				fi

				new_dts=$1
				shift
			else
				old_dts=$1
				shift
			fi
			;;

		esac
done


if [[ (${help} == 1) ]] ; then
	usage
	exit 1
fi


#_______________________________________________________________________________

if [[ -f ${new_dts} && overwrite -eq 0 ]] ; then

	echo  ""                                                             >&2
	echo  "ERROR: file '${new_dts}' already exists"                      >&2
	echo  ""                                                             >&2

	exit 2
fi


#_______________________________________________________________________________


if which overlay_convert >/dev/null ; then
	OVERLAY_CONVERT=overlay_convert
elif which ./overlay_convert >/dev/null ; then
	OVERLAY_CONVERT=./overlay_convert
else
	echo  ""                                                             >&2
	echo "ERROR: overlay_convert not found or not executable"            >&2
	echo  ""                                                             >&2

	exit 1
fi

OVERLAY_CONVERT_OPTIONS="${force} ${no_indent_fix} ${verbose}"

${OVERLAY_CONVERT} ${OVERLAY_CONVERT_OPTIONS} ${old_dts} > ${new_dts}

convert_status=$?
if [ ${convert_status} -ne 0 -a ${convert_status} -ne 3 ] ; then

	echo ""                                                              >&2
	echo "ERROR: unable to convert ${old_dts}"                           >&2
	echo ""                                                              >&2

	if [ "${force}" == "" ] ; then
		rm ${new_dts}
	fi

	exit 3
fi

if ! which dtc >/dev/null ; then

	echo  ""                                                             >&2
	echo "ERROR: dtc not found or not executable"                        >&2
	echo  "      add the location of dtc to \$PATH"                      >&2
	echo  ""                                                             >&2

	exit 1
fi

if ! diff -q                                    \
	<(dtc -@ -O dts ${old_dts} 2>/dev/null) \
	<(dtc -@ -O dts ${new_dts} 2>/dev/null) \
	> /dev/null 2>/dev/null ; then

	echo ""                                                              >&2
	echo "ERROR: ${new_dts} is not equivalent to ${old_dts}"             >&2
	echo ""                                                              >&2

	exit 5
fi

if [ ${convert_status} -eq 3 ] ; then
	exit 4
fi