1#! /bin/sh 2# 3# This script is used to configure the linux kernel. 4# 5# It was inspired by the challenge in the original Configure script 6# to ``do something better'', combined with the actual need to ``do 7# something better'' because the old configure script wasn't flexible 8# enough. 9# 10# Please send comments / questions / bug fixes to raymondc@microsoft.com. 11# 12# Each line in the config file is a command. 13# 14# # internal comment 15# 16# Lines beginning with a `#' are ignored. 17# 18# : message 19# 20# `:' causes the line to be echoed to the screen. 21# 22# * external comment 23# 24# `*' causes the line to be placed in the output 25# configuration file as a comment as well as being 26# echoed to the screen. 27# 28# if condition 29# ... commands ... 30# else 31# ... commands ... 32# fi 33# 34# This does the obvious thing. The `else' clause is 35# optional. Conditionals can be nested. 36# 37# The `condition' can be any valid bash expression. 38# They typically involve tests against environment 39# variables set by configuration options. For example, 40# 41# if [ "$CONFIG_SCSI" = "y" ] 42# ...More stuff... 43# fi 44# 45# Note! That there is no `then' keyword. 46# 47# bool 'prompt' CONFIG_VARIABLE default 48# 49# This prompts the user for a boolean value. 50# The prompt may not contain an apostrophe. 51# `default' should be either `y' or `n'. 52# The user's response is recorded in four places. 53# 54# In .config, if `y' 55# CONFIG_VARIABLE = CONFIG_VARIABLE 56# In .config, if `n' 57# # CONFIG_VARIABLE is not set 58# 59# In autoconf.h, if `y' 60# #define CONFIG_VARIABLE 1 61# In autoconf.h, if `n' 62# #undef CONFIG_VARIABLE 63# 64# In config.in, if `y' 65# bool 'prompt' CONFIG_VARIABLE y 66# In config.in, if `n' 67# bool 'prompt' CONFIG_VARIABLE n 68# 69# In the environment of the Configure script, if `y' 70# CONFIG_VARIABLE = y 71# In the environment of the Configure script, if `n' 72# CONFIG_VARIABLE = n 73# 74# The value is placed into the environment of the Configure 75# script so that later parts of config.in can use the `if' 76# command to inspect the results of previous queries. 77# 78# int 'prompt' CONFIG_VARIABLE default 79# 80# This prompts the user for an integer value. 81# The prompt may not contain an apostrophe. 82# `default' should be an integer. 83# 84# The response is recorded as follows. 85# 86# In .config 87# CONFIG_VARIABLE = response 88# In autoconf.h 89# #define CONFIG_VARIABLE (response) 90# In config.in 91# int 'prompt' CONFIG_VARIABLE response 92# In the environment of the Configure script 93# CONFIG_VARIABLE = response 94# 95# 050793 - use IFS='@' to get around a bug in a pre-version of bash-1.13 96# with an empty IFS. 97 98# 99# Make sure we're really running bash. 100# 101# I would really have preferred to write this script in a language with 102# better string handling, but alas, bash is the only scripting language 103# that I can be reasonable sure everybody has on their linux machine. 104# 105[ -z "$BASH" ] && { echo "Configure requires bash" 1>&2; exit 1; } 106 107# Disable filename globbing once and for all. 108# Enable function cacheing. 109set -f -h 110 111# 112# readln reads a line into $ans. 113# 114# readln prompt default 115# 116function readln () { 117 echo -n "$1" 118 IFS='@' read ans </dev/tty || exit 1 119 [ -z "$ans" ] && ans=$2 120} 121 122# bool processes a boolean argument 123# 124# bool tail 125# 126function bool () { 127 # Slimier hack to get bash to rescan a line. 128 eval "set -- $1" 129 ans="" 130 while [ "$ans" != "y" -a "$ans" != "n" ]; do 131 readln "$1 ($2) [$3] " "$3" 132 done 133 if [ "$ans" = "y" ]; then 134 echo "$2 = $2" >>$CONFIG 135 echo "#define $2 1" >>$CONFIG_H 136 else 137 echo "# $2 is not set" >>$CONFIG 138 echo "#undef $2" >>$CONFIG_H 139 fi 140 raw_input_line="bool '$1' $2 $ans" 141 eval "$2=$ans" 142} 143 144# int processes an integer argument 145# 146# int tail 147# 148function int () { 149 # Slimier hack to get bash to rescan a line. 150 eval "set -- $1" 151 ans="x" 152 while [ $[$ans+0] != "$ans" ]; do 153 readln "$1 ($2) [$3] " "$3" 154 done 155 echo "$2 = $ans" >>$CONFIG 156 echo "#define $2 ($ans)" >>$CONFIG_H 157 raw_input_line="int '$1' $2 $ans" 158 eval "$2=$ans" 159} 160 161CONFIG=.tmpconfig 162CONFIG_H=include/linux/autoconf.h 163trap "rm -f $CONFIG $CONFIG_H config.new ; exit 1" 1 2 164 165# 166# Make sure we start out with a clean slate. 167# 168> config.new 169echo "#" > $CONFIG 170echo "# Automatically generated make config: don't edit" >> $CONFIG 171echo "#" >> $CONFIG 172 173echo "/*" > $CONFIG_H 174echo " * Automatically generated C config: don't edit" >> $CONFIG_H 175echo " */" >> $CONFIG_H 176 177stack='' 178branch='t' 179 180while IFS='@' read raw_input_line 181do 182 # Slimy hack to get bash to rescan a line. 183 read cmd rest <<-END_OF_COMMAND 184 $raw_input_line 185 END_OF_COMMAND 186 187 if [ "$cmd" = "*" ]; then 188 if [ "$branch" = "t" ]; then 189 echo "$raw_input_line" 190 echo "# $rest" >>$CONFIG 191 if [ "$prevcmd" != "*" ]; then 192 echo >>$CONFIG_H 193 echo "/* $rest" >>$CONFIG_H 194 else 195 echo " * $rest" >>$CONFIG_H 196 fi 197 prevcmd="*" 198 fi 199 else 200 [ "$prevcmd" = "*" ] && echo " */" >>$CONFIG_H 201 prevcmd="" 202 case "$cmd" in 203 :) [ "$branch" = "t" ] && echo "$raw_input_line" ;; 204 int) [ "$branch" = "t" ] && int "$rest" ;; 205 bool) [ "$branch" = "t" ] && bool "$rest" ;; 206 exec) [ "$branch" = "t" ] && ( sh -c "$rest" ) ;; 207 if) stack="$branch $stack" 208 if [ "$branch" = "t" ] && eval "$rest"; then 209 branch=t 210 else 211 branch=f 212 fi ;; 213 else) if [ "$branch" = "t" ]; then 214 branch=f 215 else 216 read branch rest <<-END_OF_STACK 217 $stack 218 END_OF_STACK 219 fi ;; 220 fi) [ -z "$stack" ] && echo "Error! Extra fi." 1>&2 221 read branch stack <<-END_OF_STACK 222 $stack 223 END_OF_STACK 224 ;; 225 esac 226 fi 227 echo "$raw_input_line" >>config.new 228done 229[ "$prevcmd" = "*" ] && echo " */" >>$CONFIG_H 230 231[ -z "$stack" ] || echo "Error! Untermiated if." 1>&2 232 233mv config.in config.old 234mv config.new config.in 235 236echo 237echo "The linux kernel is now hopefully configured for your setup." 238echo "Check the top-level Makefile for additional configuration," 239echo "and do a 'make dep ; make clean' if you want to be sure all" 240echo "the files are correctly re-made" 241echo 242 243exit 0 244