#! /bin/sh
#
# This script is used to configure an Aversive project. It is mainly
# coming from the Linux Kernel Configure script. Thanks to the authors.
#



# Make sure we're really running bash.
#
# I would really have preferred to write this script in a language with
# better string handling, but alas, bash is the only scripting language
# that I can be reasonable sure everybody has on their linux machine.
#
[ -z "$BASH" ] && { echo "Configure requires bash" 1>&2; exit 1; }

# Disable filename globbing once and for all.
# Enable function cacheing.
set -f -h

#
# Dummy functions for use with a config.in modified for menuconf
#
function mainmenu_option () {
	:
}
function mainmenu_name () {
	:
}
function endmenu () {
	:
}

#
# help prints the corresponding help text from ${HELP_FILE} to stdout
#
#       help variable
#
function help () {
  if [ -f ${HELP_FILE} ]
  then
     #first escape regexp special characters in the argument:
     var=$(echo "$1"|sed 's/[][\/.^$*]/\\&/g')
     #now pick out the right help text:
     text=$(sed -n "/^$var[ 	]*\$/,\${
			/^$var[ 	]*\$/c\\
${var}:\\

			/^#/b
			/^[^ 	]/q
			p
		    }" ${HELP_FILE})
     if [ -z "$text" ]
     then
	  echo; echo "  Sorry, no help available for this option yet.";echo
     else
	  (echo; echo "$text") | ${PAGER:-more}
     fi
  else
     echo;
     echo "  Can't access the file ${HELP_FILE} which"
     echo "  should contain the help texts."
     echo
  fi
}


#
# readln reads a line into $ans.
#
#	readln prompt default oldval
#
function readln () {
	if [ "$DEFAULT" = "-d" ]; then
		echo "$1"
		ans=$2
	else
		echo -n "$1"
		[ -z "$3" ] && echo -n "(NEW) "
		IFS='@' read ans || exit 1
		[ -z "$ans" ] && ans=$2
	fi
}

#
# comment does some pretty-printing
#
#	comment 'xxx'
# 
function comment () {
	echo "*"; echo "* $1" ; echo "*"
	(echo "" ; echo "#"; echo "# $1" ; echo "#") >>$CONFIG
	(echo "" ; echo "/*"; echo " * $1" ; echo " */") >>$CONFIG_H
}

#
# define_bool sets the value of a boolean argument
#
#	define_bool define value
#

function define_bool () {
	case "$2" in
	 "y")
		echo "$1=y" >>$CONFIG
		echo "#define $1 1" >>$CONFIG_H
		;;

	 "n")
		echo "# $1 is not set" >>$CONFIG
		echo "#undef  $1" >>$CONFIG_H
		;;
	esac
	eval "$1=$2"
}

#
# bool processes a boolean argument
#
#	bool question define
#
function bool () {
	old=$(eval echo "\${$2}")
	def=${old:-'n'}
	case "$def" in
	 "y" | "m") defprompt="Y/n/?"
	      def="y"
	      ;;
	 "n") defprompt="N/y/?"
	      ;;
	esac
	while :; do
	  readln "$1 ($2) [$defprompt] " "$def" "$old"
	  case "$ans" in
	    [yY] | [yY]es ) define_bool "$2" "y"
			    break;;
	    [nN] | [nN]o )  define_bool "$2" "n"
			    break;;
	    * )             help "$2"
			    ;;
	  esac
	done
}

function dep_bool () {
	ques=$1
	var=$2
	shift 2
	while [ $# -gt 0 ]; do
	  case "$1" in
	    n)
	      define_bool "$var" "n"
	      return
	      ;;
	  esac
	  shift
	done

	bool "$ques" "$var"
}


#
# define_int sets the value of a integer argument
#
#	define_int define value
#
function define_int () {
	echo "$1=$2" >>$CONFIG
	echo "#define $1 ($2)" >>$CONFIG_H
	eval "$1=$2"
}

#
# int processes an integer argument with optional limits
#
#	int question define default [min max]
#
function int () {
	old=$(eval echo "\${$2}")
	def=${old:-$3}
	if [ $# -gt 3 ]; then
	  min=$4
	else
	  min=-1000000000    # !!
	fi
	if [ $# -gt 4 ]; then
	  max=$5
	else
	  max=1000000000     # !!
	fi
	while :; do
	  readln "$1 ($2) [$def] " "$def" "$old"
	  echo [$ans]
	  if expr \( \( $ans + 0 \) \>= $min \) \& \( $ans \<= $max \) >/dev/null 2>&1 ; then
            define_int "$2" "$ans"
	    break
          else
	    help "$2"
          fi
	done
}

#
# define_hex sets the value of a hexadecimal argument
#
#	define_hex define value
#
function define_hex () {
	echo "$1=$2" >>$CONFIG
	echo "#define $1 0x${2#*[x,X]}" >>$CONFIG_H
	eval "$1=$2"
}

#
# hex processes an hexadecimal argument
#
#	hex question define default
#
function hex () {
	old=$(eval echo "\${$2}")
	def=${old:-$3}
	def=${def#*[x,X]}
	while :; do
	  readln "$1 ($2) [$def] " "$def" "$old"
	  ans=${ans#*[x,X]}
	  if expr "$ans" : '[0-9a-fA-F][0-9a-fA-F]*$' > /dev/null; then
	    define_hex "$2" "$ans"
	    break
	  else
	    help "$2"
	  fi
	done
}

#
# define_string sets the value of a string argument
#
#	define_string define value
#
function define_string () {
	echo "$1=\"$2\"" >>$CONFIG
	echo "#define $1 \"$2\"" >>$CONFIG_H
	eval "$1=\"$2\""
}

#
# string processes a string argument
#
#	string question define default
#
function string () {
	old=$(eval echo "\${$2}")
	def=${old:-$3}
	while :; do
          if [ "$old" = "?" ]; then
             readln "$1 ($2) [$def] " "$def" ""
          else
	     readln "$1 ($2) [$def] " "$def" "$old"
          fi
	  if [ "$ans" = "?" ]; then
	    help "$2"
	  else
	    break
	  fi
	done
	define_string "$2" "$ans"
}
#
# choice processes a choice list (1-out-of-n)
#
#	choice question choice-list default
#
# The choice list has a syntax of:
#	NAME WHITESPACE VALUE { WHITESPACE NAME WHITESPACE VALUE }
# The user may enter any unique prefix of one of the NAMEs and
# choice will define VALUE as if it were a boolean option.
# VALUE must be in all uppercase.  Normally, VALUE is of the
# form CONFIG_<something>.  Thus, if the user selects <something>,
# the CPP symbol CONFIG_<something> will be defined and the
# shell variable CONFIG_<something> will be set to "y".
#
function choice () {
	question="$1"
	choices="$2"
	old=
	def=$3

	# determine default answer:
	names=""
	set -- $choices
	firstvar=$2
	while [ -n "$2" ]; do
		if [ -n "$names" ]; then
			names="$names, $1"
		else
			names="$1"
		fi
		if [ "$(eval echo \"\${$2}\")" = "y" ]; then
			old=$1
			def=$1
		fi
		shift; shift
	done

	val=""
	while [ -z "$val" ]; do
		ambg=n
		readln "$question ($names) [$def] " "$def" "$old"
		ans=$(echo $ans | tr a-z A-Z)
		set -- $choices
		while [ -n "$1" ]; do
			name=$(echo $1 | tr a-z A-Z)
			case "$name" in
				"$ans"* | */"$ans"* )
					case "$name" in
						"$ans" | */"$ans"/* | \
						"$ans"/* | */"$ans" )
							val="$2"
							break # exact match
						;;
					esac
					if [ -n "$val" ]; then
						echo;echo \
		"  Sorry, \"$ans\" is ambiguous; please enter a longer string."
						echo
						val=""
						ambg=y
						break
					else
						val="$2"
					fi;;
			esac
			shift; shift
		done
		if [ "$val" = "" -a "$ambg" = "n" ]; then
			help "$firstvar"
		fi
	done
	set -- $choices
	while [ -n "$2" ]; do
		if [ "$2" = "$val" ]; then
			echo "  defined $val"
			define_bool "$2" "y"
		else
			define_bool "$2" "n"
		fi
		shift; shift
	done
}

CONFIG=.tmpconfig
CONFIG_H=.tmpconfig.h
trap "rm -f $CONFIG $CONFIG_H ; exit 1" 1 2
if [ -z "$HELP_FILE" ]
then
	HELP_FILE="Documentation/Configure.help"
fi

#
# Make sure we start out with a clean slate.
#
echo "#" > $CONFIG
echo "# Automatically generated make config: don't edit" >> $CONFIG
echo "#" >> $CONFIG

echo "/*" > $CONFIG_H
echo " * Automatically generated C config: don't edit" >> $CONFIG_H
echo " */" >> $CONFIG_H
echo "#define AUTOCONF_INCLUDED" >> $CONFIG_H

DEFAULT=""
if [ "$1" = "-d" ] ; then
	DEFAULT="-d"
	shift
fi

CONFIG_IN=./config.in
if [ "$1" != "" ] ; then
	CONFIG_IN=$1
fi

DEFAULTS=$AVERSIVE_DIR/config/.config
if [ -f .config ]; then
  DEFAULTS=.config
fi

if [ -f $DEFAULTS ]; then
  echo "#"
  echo "# Using defaults found in" $DEFAULTS
  echo "#"
  . $DEFAULTS
  sed -e 's/# \(CONFIG_[^ ]*\) is not.*/\1=n/' <$DEFAULTS >.config-is-not.$$
  . .config-is-not.$$
  rm .config-is-not.$$
else
  echo "#"
  echo "# No defaults found"
  echo "#"
fi

. $CONFIG_IN

rm -f .config.old
if [ -f .config ]; then
	mv .config .config.old
fi
mv .tmpconfig .config
if [ -w "`dirname ${AUTOCONF_FILE:=include/linux/autoconf.h}`" ]; then
	mv .tmpconfig.h ${AUTOCONF_FILE:-include/linux/autoconf.h}
fi

$AVERSIVE_DIR/config/generate_aversive_config .config .aversive_conf

echo
echo "*** End of Aversive project configuration."
echo "*** Next, you should run 'make clean, then make'."
echo


exit 0