1#!/bin/sh 2# SPDX-License-Identifier: GPL-2.0 3 4TARGET=$1 5ARCH=$2 6SMP=$3 7PREEMPT=$4 8PREEMPT_RT=$5 9CC_VERSION="$6" 10LD=$7 11 12vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; } 13 14# Do not expand names 15set -f 16 17# Fix the language to get consistent output 18LC_ALL=C 19export LC_ALL 20 21if [ -z "$KBUILD_BUILD_VERSION" ]; then 22 VERSION=$(cat .version 2>/dev/null || echo 1) 23else 24 VERSION=$KBUILD_BUILD_VERSION 25fi 26 27if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then 28 TIMESTAMP=`date` 29else 30 TIMESTAMP=$KBUILD_BUILD_TIMESTAMP 31fi 32if test -z "$KBUILD_BUILD_USER"; then 33 LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/') 34else 35 LINUX_COMPILE_BY=$KBUILD_BUILD_USER 36fi 37if test -z "$KBUILD_BUILD_HOST"; then 38 LINUX_COMPILE_HOST=`uname -n` 39else 40 LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST 41fi 42 43UTS_VERSION="#$VERSION" 44CONFIG_FLAGS="" 45if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi 46if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi 47if [ -n "$PREEMPT_RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT_RT"; fi 48 49# Truncate to maximum length 50UTS_LEN=64 51UTS_VERSION="$(echo $UTS_VERSION $CONFIG_FLAGS $TIMESTAMP | cut -b -$UTS_LEN)" 52 53# Generate a temporary compile.h 54 55{ echo /\* This file is auto generated, version $VERSION \*/ 56 if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi 57 58 echo \#define UTS_MACHINE \"$ARCH\" 59 60 echo \#define UTS_VERSION \"$UTS_VERSION\" 61 62 printf '#define LINUX_COMPILE_BY "%s"\n' "$LINUX_COMPILE_BY" 63 echo \#define LINUX_COMPILE_HOST \"$LINUX_COMPILE_HOST\" 64 65 LD_VERSION=$($LD -v | head -n1 | sed 's/(compatible with [^)]*)//' \ 66 | sed 's/[[:space:]]*$//') 67 printf '#define LINUX_COMPILER "%s"\n' "$CC_VERSION, $LD_VERSION" 68} > .tmpcompile 69 70# Only replace the real compile.h if the new one is different, 71# in order to preserve the timestamp and avoid unnecessary 72# recompilations. 73# We don't consider the file changed if only the date/time changed, 74# unless KBUILD_BUILD_TIMESTAMP was explicitly set (e.g. for 75# reproducible builds with that value referring to a commit timestamp). 76# A kernel config change will increase the generation number, thus 77# causing compile.h to be updated (including date/time) due to the 78# changed comment in the 79# first line. 80 81if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then 82 IGNORE_PATTERN="UTS_VERSION" 83else 84 IGNORE_PATTERN="NOT_A_PATTERN_TO_BE_MATCHED" 85fi 86 87if [ -r $TARGET ] && \ 88 grep -v $IGNORE_PATTERN $TARGET > .tmpver.1 && \ 89 grep -v $IGNORE_PATTERN .tmpcompile > .tmpver.2 && \ 90 cmp -s .tmpver.1 .tmpver.2; then 91 rm -f .tmpcompile 92else 93 vecho " UPD $TARGET" 94 mv -f .tmpcompile $TARGET 95fi 96rm -f .tmpver.1 .tmpver.2 97