xref: /linux/scripts/mkcompile_h (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
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=$KBUILD_BUILD_TIMESTAMP
44fi
45if test -z "$KBUILD_BUILD_USER"; then
46	LINUX_COMPILE_BY=$(whoami | sed 's/\\/\\\\/')
47else
48	LINUX_COMPILE_BY=$KBUILD_BUILD_USER
49fi
50if test -z "$KBUILD_BUILD_HOST"; then
51	LINUX_COMPILE_HOST=`hostname`
52else
53	LINUX_COMPILE_HOST=$KBUILD_BUILD_HOST
54fi
55
56UTS_VERSION="#$VERSION"
57CONFIG_FLAGS=""
58if [ -n "$SMP" ] ; then CONFIG_FLAGS="SMP"; fi
59if [ -n "$PREEMPT" ] ; then CONFIG_FLAGS="$CONFIG_FLAGS PREEMPT"; fi
60UTS_VERSION="$UTS_VERSION $CONFIG_FLAGS $TIMESTAMP"
61
62# Truncate to maximum length
63
64UTS_LEN=64
65UTS_TRUNCATE="cut -b -$UTS_LEN"
66
67# Generate a temporary compile.h
68
69( echo /\* This file is auto generated, version $VERSION \*/
70  if [ -n "$CONFIG_FLAGS" ] ; then echo "/* $CONFIG_FLAGS */"; fi
71
72  echo \#define UTS_MACHINE \"$ARCH\"
73
74  echo \#define UTS_VERSION \"`echo $UTS_VERSION | $UTS_TRUNCATE`\"
75
76  echo \#define LINUX_COMPILE_BY \"`echo $LINUX_COMPILE_BY | $UTS_TRUNCATE`\"
77  echo \#define LINUX_COMPILE_HOST \"`echo $LINUX_COMPILE_HOST | $UTS_TRUNCATE`\"
78
79  echo \#define LINUX_COMPILER \"`$CC -v 2>&1 | tail -n 1`\"
80) > .tmpcompile
81
82# Only replace the real compile.h if the new one is different,
83# in order to preserve the timestamp and avoid unnecessary
84# recompilations.
85# We don't consider the file changed if only the date/time changed.
86# A kernel config change will increase the generation number, thus
87# causing compile.h to be updated (including date/time) due to the
88# changed comment in the
89# first line.
90
91if [ -r $TARGET ] && \
92      grep -v 'UTS_VERSION' $TARGET > .tmpver.1 && \
93      grep -v 'UTS_VERSION' .tmpcompile > .tmpver.2 && \
94      cmp -s .tmpver.1 .tmpver.2; then
95   rm -f .tmpcompile
96else
97   vecho "  UPD     $TARGET"
98   mv -f .tmpcompile $TARGET
99fi
100rm -f .tmpver.1 .tmpver.2
101