1 files changed, 50 insertions, 0 deletions
diff --git a/kernel/gen_kheaders.sh b/kernel/gen_kheaders.sh
new file mode 100755
index 000000000000..896a503dfb29
--- /dev/null
+++ b/kernel/gen_kheaders.sh
@@ -0,0 +1,50 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+# This script generates an archive consisting of kernel headers
+# for CONFIG_IKHEADERS.
+set -e
+tarfile=$1
+srclist=$2
+objlist=$3
+timestamp=$4
+
+dir=$(dirname "${tarfile}")
+tmpdir=${dir}/.tmp_dir
+depfile=${dir}/.$(basename "${tarfile}").d
+
+# generate dependency list.
+{
+	echo
+	echo "deps_${tarfile} := \\"
+	sed 's:\(.*\):  \1 \\:' "${srclist}"
+	sed -n '/^include\/generated\/autoconf\.h$/!s:\(.*\):  \1 \\:p' "${objlist}"
+	echo
+	echo "${tarfile}: \$(deps_${tarfile})"
+	echo
+	echo "\$(deps_${tarfile}):"
+
+} > "${depfile}"
+
+rm -rf "${tmpdir}"
+mkdir "${tmpdir}"
+
+# shellcheck disable=SC2154 # srctree is passed as an env variable
+sed "s:^${srctree}/::" "${srclist}" | ${TAR} -c -f - -C "${srctree}" -T - | ${TAR} -xf - -C "${tmpdir}"
+${TAR} -c -f - -T "${objlist}" | ${TAR} -xf - -C "${tmpdir}"
+
+# Remove comments except SDPX lines
+# Use a temporary file to store directory contents to prevent find/xargs from
+# seeing temporary files created by perl.
+find "${tmpdir}" -type f -print0 > "${tmpdir}.contents.txt"
+xargs -0 -P8 -n1 \
+	perl -pi -e 'BEGIN {undef $/;}; s/\/\*((?!SPDX).)*?\*\///smg;' \
+	< "${tmpdir}.contents.txt"
+rm -f "${tmpdir}.contents.txt"
+
+# Create archive and try to normalize metadata for reproducibility.
+${TAR} "${timestamp:+--mtime=$timestamp}" \
+    --owner=0 --group=0 --sort=name --numeric-owner --mode=u=rw,go=r,a+X \
+    -I "${XZ}" -cf "${tarfile}" -C "${tmpdir}/" . > /dev/null
+
+rm -rf "${tmpdir}"