xref: /openbmc/linux/scripts/mkcompile_h (revision f84fdf8d) 
1#!/bin/sh
2# SPDX-License-Identifier: GPL-2.0
3
4TARGET=$1
5ARCH=$2
6SMP=$3
7PREEMPT=$4
8PREEMPT_RT=$5
9CC=$6
10
11vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
12
13# Do not expand names
14set -f
15
16# Fix the language to get consistent output
17LC_ALL=C
18export LC_ALL
19
20if [ -z "$KBUILD_BUILD_VERSION" ]; then
21	VERSION=$(cat .version 2>/dev/null || echo 1)
22else
23	VERSION=$KBUILD_BUILD_VERSION
24fi
25
26if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
27	TIMESTAMP=`date`
28else
29	TIMESTAMP=$KBUILD_BUILD_TIMESTAMP
30fi
31if test -z "$KBUILD_BUILD_USER"; then
32	LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
33else
34	LINUX_COMPILE_BY=$KBUILD_BUILD_USER
35fi
36if test -z "$KBUILD_BUILD_HOST"; then
37	LINUX_COMPILE_HOST=`hostname`
38else
39	LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST
40fi
41
42UTS_VERSION="#$VERSION"
43CONFIG_FLAGS=""
44if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
45if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
46if [ -n "$PREEMPT_RT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT_RT"; fi
47
48# Truncate to maximum length
49UTS_LEN=64
50UTS_VERSION="$(echo $UTS_VERSION $CONFIG_FLAGS $TIMESTAMP | cut -b -$UTS_LEN)"
51
52# Generate a temporary compile.h
53
54{ echo /\* This file is auto generated, version $VERSION \*/
55  if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
56
57  echo \#define UTS_MACHINE \"$ARCH\"
58
59  echo \#define UTS_VERSION \"$UTS_VERSION\"
60
61  printf '#define LINUX_COMPILE_BY "%s"\n' "$LINUX_COMPILE_BY"
62  echo \#define LINUX_COMPILE_HOST \"$LINUX_COMPILE_HOST\"
63
64  echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | grep ' version ' | sed 's/[[:space:]]*$//'`\"
65} > .tmpcompile
66
67# Only replace the real compile.h if the new one is different,
68# in order to preserve the timestamp and avoid unnecessary
69# recompilations.
70# We don't consider the file changed if only the date/time changed.
71# A kernel config change will increase the generation number, thus
72# causing compile.h to be updated (including date/time) due to the
73# changed comment in the
74# first line.
75
76if [ -r $TARGET ] && \
77      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
78      grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
79      cmp -s .tmpver.1 .tmpver.2; then
80   rm -f .tmpcompile
81else
82   vecho "  UPD     $TARGET"
83   mv -f .tmpcompile $TARGET
84fi
85rm -f .tmpver.1 .tmpver.2
86