1#!/bin/sh 2# SPDX-License-Identifier: GPL-2.0 3 4# This script generates an archive consisting of kernel headers 5# for CONFIG_IKHEADERS. 6set -e 7sfile="$(readlink -f "$0")" 8outdir="$(pwd)" 9tarfile=$1 10cpio_dir=$outdir/$tarfile.tmp 11 12dir_list=" 13include/ 14arch/$SRCARCH/include/ 15" 16 17# Support incremental builds by skipping archive generation 18# if timestamps of files being archived are not changed. 19 20# This block is useful for debugging the incremental builds. 21# Uncomment it for debugging. 22# if [ ! -f /tmp/iter ]; then iter=1; echo 1 > /tmp/iter; 23# else iter=$(($(cat /tmp/iter) + 1)); echo $iter > /tmp/iter; fi 24# find $all_dirs -name "*.h" | xargs ls -l > /tmp/ls-$iter 25 26all_dirs= 27if [ "$building_out_of_srctree" ]; then 28 for d in $dir_list; do 29 all_dirs="$all_dirs $srctree/$d" 30 done 31fi 32all_dirs="$all_dirs $dir_list" 33 34# include/generated/compile.h is ignored because it is touched even when none 35# of the source files changed. 36# 37# When Kconfig regenerates include/generated/autoconf.h, its timestamp is 38# updated, but the contents might be still the same. When any CONFIG option is 39# changed, Kconfig touches the corresponding timestamp file include/config/*. 40# Hence, the md5sum detects the configuration change anyway. We do not need to 41# check include/generated/autoconf.h explicitly. 42# 43# Ignore them for md5 calculation to avoid pointless regeneration. 44headers_md5="$(find $all_dirs -name "*.h" | 45 grep -v "include/generated/compile.h" | 46 grep -v "include/generated/autoconf.h" | 47 xargs ls -l | md5sum | cut -d ' ' -f1)" 48 49# Any changes to this script will also cause a rebuild of the archive. 50this_file_md5="$(ls -l $sfile | md5sum | cut -d ' ' -f1)" 51if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi 52if [ -f kernel/kheaders.md5 ] && 53 [ "$(head -n 1 kernel/kheaders.md5)" = "$headers_md5" ] && 54 [ "$(head -n 2 kernel/kheaders.md5 | tail -n 1)" = "$this_file_md5" ] && 55 [ "$(tail -n 1 kernel/kheaders.md5)" = "$tarfile_md5" ]; then 56 exit 57fi 58 59echo " GEN $tarfile" 60 61rm -rf $cpio_dir 62mkdir $cpio_dir 63 64if [ "$building_out_of_srctree" ]; then 65 ( 66 cd $srctree 67 for f in $dir_list 68 do find "$f" -name "*.h"; 69 done | cpio --quiet -L -pd $cpio_dir 70 ) 71fi 72 73# The second CPIO can complain if files already exist which can happen with out 74# of tree builds having stale headers in srctree. Just silence CPIO for now. 75for f in $dir_list; 76 do find "$f" -name "*.h"; 77done | cpio --quiet -L -pdu $cpio_dir >/dev/null 2>&1 78 79# Remove comments except SDPX lines 80find $cpio_dir -type f -print0 | 81 xargs -0 -P8 -n1 perl -pi -e 'BEGIN {undef $/;}; s/\/\*((?!SPDX).)*?\*\///smg;' 82 83# Create archive and try to normalize metadata for reproducibility. 84# For compatibility with older versions of tar, files are fed to tar 85# pre-sorted, as --sort=name might not be available. 86find $cpio_dir -printf "./%P\n" | LC_ALL=C sort | \ 87 tar "${KBUILD_BUILD_TIMESTAMP:+--mtime=$KBUILD_BUILD_TIMESTAMP}" \ 88 --owner=0 --group=0 --numeric-owner --no-recursion \ 89 -I $XZ -cf $tarfile -C $cpio_dir/ -T - > /dev/null 90 91echo $headers_md5 > kernel/kheaders.md5 92echo "$this_file_md5" >> kernel/kheaders.md5 93echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5 94 95rm -rf $cpio_dir 96