1#!/bin/sh
2# SPDX-License-Identifier: GPL-2.0
3
4TARGET=$1
5ARCH=$2
6SMP=$3
7PREEMPT=$4
8CC=$5
9
10vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
11
12# If compile.h exists already and we don't own autoconf.h
13# (i.e. we're not the same user who did make *config), don't
14# modify compile.h
15# So "sudo make install" won't change the "compiled by <user>"
16# do "compiled by root"
17
18if [ -r $TARGET -a ! -O include/generated/autoconf.h ]; then
19  vecho "  SKIPPED $TARGET"
20  exit 0
21fi
22
23# Do not expand names
24set -f
25
26# Fix the language to get consistent output
27LC_ALL=C
28export LC_ALL
29
30if [ -z "$KBUILD_BUILD_VERSION" ]; then
31	VERSION=$(cat .version 2>/dev/null || echo 1)
32else
33	VERSION=$KBUILD_BUILD_VERSION
34fi
35
36if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
37	TIMESTAMP=`date`
38else
39	TIMESTAMP=$KBUILD_BUILD_TIMESTAMP
40fi
41if test -z "$KBUILD_BUILD_USER"; then
42	LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
43else
44	LINUX_COMPILE_BY=$KBUILD_BUILD_USER
45fi
46if test -z "$KBUILD_BUILD_HOST"; then
47	LINUX_COMPILE_HOST=`hostname`
48else
49	LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST
50fi
51
52UTS_VERSION="#$VERSION"
53CONFIG_FLAGS=""
54if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
55if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
56UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
57
58# Truncate to maximum length
59
60UTS_LEN=64
61UTS_TRUNCATE="cut -b -$UTS_LEN"
62
63# Generate a temporary compile.h
64
65( echo /\* This file is auto generated, version $VERSION \*/
66  if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
67
68  echo \#define UTS_MACHINE \"$ARCH\"
69
70  echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\"
71
72  echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\"
73  echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\"
74
75  echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | grep ' version ' | sed 's/[[:space:]]*$//'`\"
76) > .tmpcompile
77
78# Only replace the real compile.h if the new one is different,
79# in order to preserve the timestamp and avoid unnecessary
80# recompilations.
81# We don't consider the file changed if only the date/time changed.
82# A kernel config change will increase the generation number, thus
83# causing compile.h to be updated (including date/time) due to the
84# changed comment in the
85# first line.
86
87if [ -r $TARGET ] && \
88      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
89      grep -v 'UTS_VERSION' .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