xref: /openbmc/linux/scripts/mkcompile_h (revision 25985edc) 
1#!/bin/sh
2
3TARGET=$1
4ARCH=$2
5SMP=$3
6PREEMPT=$4
7CC=$5
8
9vecho() { [ "${quiet}" = "silent_" ] || echo "$@" ; }
10
11# If compile.h exists already and we don't own autoconf.h
12# (i.e. we're not the same user who did make *config), don't
13# modify compile.h
14# So "sudo make install" won't change the "compiled by <user>"
15# do "compiled by root"
16
17if [ -r $TARGET -a ! -O include/generated/autoconf.h ]; then
18  vecho "  SKIPPED $TARGET"
19  exit 0
20fi
21
22# Do not expand names
23set -f
24
25# Fix the language to get consistent output
26LC_ALL=C
27export LC_ALL
28
29if [ -z "$KBUILD_BUILD_VERSION" ]; then
30	if [ -r .version ]; then
31		VERSION=`cat .version`
32	else
33		VERSION=0
34		echo 0 > .version
35	fi
36else
37	VERSION=$KBUILD_BUILD_VERSION
38fi
39
40if [ -z "$KBUILD_BUILD_TIMESTAMP" ]; then
41	TIMESTAMP=`date`
42else
43	TIMESTAMP=$KBUILD_BUILD_TIMESTAMP
44fi
45
46UTS_VERSION="#$VERSION"
47CONFIG_FLAGS=""
48if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
49if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
50UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
51
52# Truncate to maximum length
53
54UTS_LEN=64
55UTS_TRUNCATE="cut -b -$UTS_LEN"
56
57# Generate a temporary compile.h
58
59( echo /\* This file is auto generated, version $VERSION \*/
60  if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
61
62  echo \#define UTS_MACHINE \"$ARCH\"
63
64  echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\"
65
66  echo \#define LINUX_COMPILE_TIME \"`date +%T`\"
67  echo \#define LINUX_COMPILE_BY \"`whoami`\"
68  echo \#define LINUX_COMPILE_HOST \"`hostname | $UTS_TRUNCATE`\"
69
70  domain=`dnsdomainname 2> /dev/null`
71  if [ -z "$domain" ]; then
72    domain=`domainname 2> /dev/null`
73  fi
74
75  if [ -n "$domain" ]; then
76    echo \#define LINUX_COMPILE_DOMAIN \"`echo $domain | $UTS_TRUNCATE`\"
77  else
78    echo \#define LINUX_COMPILE_DOMAIN
79  fi
80
81  echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\"
82) > .tmpcompile
83
84# Only replace the real compile.h if the new one is different,
85# in order to preserve the timestamp and avoid unnecessary
86# recompilations.
87# We don't consider the file changed if only the date/time changed.
88# A kernel config change will increase the generation number, thus
89# causing compile.h to be updated (including date/time) due to the
90# changed comment in the
91# first line.
92
93if [ -r $TARGET ] && \
94      grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' $TARGET > .tmpver.1 && \
95      grep -v 'UTS_VERSION\|LINUX_COMPILE_TIME' .tmpcompile > .tmpver.2 && \
96      cmp -s .tmpver.1 .tmpver.2; then
97   rm -f .tmpcompile
98else
99   vecho "  UPD     $TARGET"
100   mv -f .tmpcompile $TARGET
101fi
102rm -f .tmpver.1 .tmpver.2
103