#!/bin/sh
set -e

srcdir="$1"
objects="$2"
log="$3"
shift 3

dkms_dir="$1"
abi_flavour="$2"
sign="$3"
pkgname="$4"
pkgdir="$5"
dbgpkgdir="$6"
package="$7"
shift 7

build="$( dirname "$objects" )/build"

# Copy over the objects ready for reconstruction.  The objects copy
# contains the *.o files. For our purposes we only want the *.o files,
# elide the rest. And .mod files for ld linking in recentish kernels.
mkdir -p "$pkgdir/bits/scripts"
(
	gcc_variant1=$(gcc --version | head -1 | sed -e 's/^gcc/GCC:/')
	gcc_variant2=$(gcc --version | head -1 | sed -e 's/^\(gcc\) \((.*)\) \(.*\)$/\1 version \3 \2/')
	cd "$objects" || exit 1
	find -name \*.o -o -name \*.mod | \
	while read file
	do
		cp --parents "$file" "$pkgdir/bits"
		"$srcdir/debian/scripts/fix-filenames" "$pkgdir/bits/$file" "$gcc_variant1"
		"$srcdir/debian/scripts/fix-filenames" "$pkgdir/bits/$file" "$gcc_variant2"
	done
)

# Install the support files we need.
echo "II: copying support files ..."
for lds_src in \
	"$dkms_dir/headers/linux-headers-$abi_flavour/scripts/module.lds" \
	"/usr/src/linux-headers-$abi_flavour/scripts/module.lds" \
	"$dkms_dir/headers/linux-headers-$abi_flavour/scripts/module-common.lds" \
	"/usr/src/linux-headers-$abi_flavour/scripts/module-common.lds"
do
	[ ! -f "$lds_src" ] && continue
	echo "II: copying support files ... found $lds_src"
	cp "$lds_src" "$pkgdir/bits/scripts"
	break
done

# Build helper scripts.
cat - <<'EOL' >"$pkgdir/bits/BUILD"
[ "$1" = "unsigned" ] && { signed_only=:; shift; }
[ "$1" = "nocheck" ] && { check_only=:; shift; }
EOL
grep /usr/bin/ld.bfd "$log" | grep -v scripts/genksyms/genksyms | grep -v "warning:\|NOTE:" | sed -e "s@$build/@@g" >>"$pkgdir/bits/BUILD"
sed -e 's/.*-o  *\([^ ]*\) .*/rm -f \1/g' <"$pkgdir/bits/BUILD" >"$pkgdir/bits/CLEAN"

# As the builds contain the absolute filenames as used.  Use RECONSTRUCT to
# rebuild the .ko's, sign them, pull off the signatures and then finally clean
# up again.
(
	cd "$pkgdir/bits"

	# Add checksum check.
	echo "\$check_only sha256sum -c SHA256SUMS || exit 1" >>"$pkgdir/bits/BUILD"

	# Add .ko handling to the CLEAN/BUILD dance.
	for ko in "$pkgdir"/*.ko
	do
		ko=$(basename "$ko")
		echo "\$signed_only cat '$ko' '$ko.sig' >'../$ko'" >>"$pkgdir/bits/BUILD"
		echo "\$signed_only rm -f '$ko'" >>"$pkgdir/bits/BUILD"
		echo "rm -f '../$ko'" >>"$pkgdir/bits/CLEAN"
	done

	# Clear out anything we are not going to distribute and build unsigned .kos.
	sh ./CLEAN
	sh ./BUILD unsigned nocheck

	if [ "$sign" = "--custom" ]; then
		# We are building for and archive custom signing upload.  Keep everything.
		:
	elif [ "$sign" = "--lrm" ]; then
		# We are in the LRM build; grab sha256 checksums and clean up.
		sha256sum -b *.ko >"SHA256SUMS"
		sh ./CLEAN

	else
		# We are in the main kernel, put the .kos together as we will
		# on the users machine, sign them, and keep just the signature.
		: >"SHA256SUMS"
		for ko in *.ko
		do
			echo "detached-signature $ko"
			$sign "$ko" "$ko.signed"
			length=$( stat --format %s "$ko" )
			dd if="$ko.signed" of="$ko.sig" bs=1 skip="$length" 2>/dev/null

			rm -f "$ko.signed"
			# Keep a checksum of the pre-signed object so we can check it is
			# built correctly in LRM.
			sha256sum -b "$ko" >>"SHA256SUMS"
		done

		# Clean out anything which not a signature.
		mv "$pkgdir/bits/"*.sig "$pkgdir"
		mv "$pkgdir/bits/SHA256SUMS" "$pkgdir"
		find "$pkgdir" -name \*.sig -prune -o -name SHA256SUMS -prune -o -type f -print | xargs rm -f
		find "$pkgdir" -depth -type d -print | xargs rmdir --ignore-fail-on-non-empty
	fi
)