xref: /openbmc/linux/scripts/mkcompile_h (revision 3a83e4e6) 
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=`hostname`
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# A kernel config change will increase the generation number, thus
75# causing compile.h to be updated (including date/time) due to the
76# changed comment in the
77# first line.
78
79if [ -r $TARGET ] && \
80      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
81      grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
82      cmp -s .tmpver.1 .tmpver.2; then
83   rm -f .tmpcompile
84else
85   vecho "  UPD     $TARGET"
86   mv -f .tmpcompile $TARGET
87fi
88rm -f .tmpver.1 .tmpver.2
89