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)" = "$tarfile_md5" ]; then 56 exit 57fi 58 59if [ "${quiet}" != "silent_" ]; then 60 echo " GEN $tarfile" 61fi 62 63rm -rf $cpio_dir 64mkdir $cpio_dir 65 66if [ "$building_out_of_srctree" ]; then 67 ( 68 cd $srctree 69 for f in $dir_list 70 do find "$f" -name "*.h"; 71 done | cpio --quiet -pd $cpio_dir 72 ) 73fi 74 75# The second CPIO can complain if files already exist which can happen with out 76# of tree builds having stale headers in srctree. Just silence CPIO for now. 77for f in $dir_list; 78 do find "$f" -name "*.h"; 79done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1 80 81# Remove comments except SDPX lines 82find $cpio_dir -type f -print0 | 83 xargs -0 -P8 -n1 perl -pi -e 'BEGIN {undef $/;}; s/\/\*((?!SPDX).)*?\*\///smg;' 84 85# Create archive and try to normalize metadata for reproducibility. 86# For compatibility with older versions of tar, files are fed to tar 87# pre-sorted, as --sort=name might not be available. 88find $cpio_dir -printf "./%P\n" | LC_ALL=C sort | \ 89 tar "${KBUILD_BUILD_TIMESTAMP:+--mtime=$KBUILD_BUILD_TIMESTAMP}" \ 90 --owner=0 --group=0 --numeric-owner --no-recursion \ 91 -I $XZ -cf $tarfile -C $cpio_dir/ -T - > /dev/null 92 93echo $headers_md5 > kernel/kheaders.md5 94echo "$this_file_md5" >> kernel/kheaders.md5 95echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5 96 97rm -rf $cpio_dir 98