#!/bin/sh

# This is a flexible yet simple configure script that can be used instead of
# GNU autoconf for simple projects written in C. It depends on the file
# config.config for application-specific globals and the files in config.d/ for
# tests to perform.


# Copyright (C) 2004 Jonas Jensen <jbj@knef.dk>
# 
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

#
# Default options
#
app="the application"
prefix=/usr/local
env_vars="CC CFLAGS CPPFLAGS LDFLAGS"
def_CC=cc
def_CFLAGS="-O3 -Wall"
MAKE_VARS=

if [ -f config.config ]; then
    . ./config.config
fi

#
# Helper functions
#

echo1() { echo $ECHO_N "$* $ECHO_C"; }
echo2() { echo "$ECHO_T$*"; }

conftest() {
    conftest_compile && conftest_link
}

conftest_compile() {
    cat >&5 << EOF

Compiling:
---------------------------
EOF
    cat conftest.c >&5
    echo "---------------------------" >&5
    echo "$CC -c $CPPFLAGS $CFLAGS -o conftest.o conftest.c" >&5

    rm -f conftest.o
    $CC -c $CPPFLAGS $CFLAGS -o conftest.o conftest.c >&5 2>&5 \
	&& [ -f conftest.o ]
}

conftest_link() {
    echo "$CC -o conftest conftest.o $LDFLAGS" >&5
    echo >&5
    $CC -o conftest conftest.o $LDFLAGS >&5 2>&5 \
	&& [ -x conftest ] && ./conftest 2>&5
}

conftest_define() {
    echo1 "$2"
    if conftest; then
	echo "#define $1 1" >> config.h
	echo2 "yes"
	return 0
    else
	echo2 "no"
	return 1
    fi
}

#
# Initialize
#
exec 5>config.log
date >&5

[ -d config.d ] || {
    echo "Directory config.d not found. Run configure from the source root."
    exit 1
}

if mv -f config.h config.h.bak 2>/dev/null; then
    trap "mv config.h.bak config.h" 0
fi
cat > config.h << EOF
/* XXX This file was automatically generated by configure. */

EOF

#
# Environment
#
for var in $env_vars; do
    eval "$var=\${$var:-\$def_$var}"
done

#
# Parse arguments
#
for option do
    case "$option" in

    --help)
	cat << EOF
This will configure $app for your system.

Options:
  --prefix=DIR    Path to install under [$prefix]
  CC=COMMAND      C compiler to use [$CC]
  CFLAGS=OPTIONS  C compiler flags [$CFLAGS]
EOF
	exit
	;;

    --strict)
	CFLAGS="$CFLAGS -std=c9x -W -Wshadow -Wpointer-arith -Wstrict-prototypes -Wmissing-prototypes -Wredundant-decls"
	echo "#define _POSIX_C_SOURCE 200112L" >> config.h
	echo "#define _XOPEN_SOURCE 600" >> config.h
	;;

    --*=*)
	arg=`echo "$option"|cut -d= -f 2-`
	case "$option" in
	--prefix=*)
	    prefix="$arg"
	    ;;
	*)
	    echo "configure: warning: ignoring option $option"
	    ;;
	esac
	;;

    *=*)
	#export "$option" # doesn't work on Solaris

	var=`echo "$option"|cut -d= -f 1`
	arg=`echo "$option"|cut -d= -f 2-`
	eval "$var='$arg'"
    esac
done

#
# Do tests
#

# echo test, stolen from GNU autoconf. This really shows UNIX at its worst...
case `echo "testing\c"; echo 1,2,3`,`echo -n testing; echo 1,2,3` in
  *c*,-n*) ECHO_N= ECHO_C='
' ECHO_T='	' ;;
  *c*,*  ) ECHO_N=-n ECHO_C= ECHO_T= ;;
  *)       ECHO_N= ECHO_C='\c' ECHO_T= ;;
esac

for f in config.d/*; do
    cat >&5 << EOF

configure: PERFORMING TEST $f

EOF
    . "$f"
done

#
# Clean up
#
trap "" 0
rm -f config.h.bak conftest.c conftest.o conftest

#
# Generate Makefile
#
make clean >/dev/null 2>&1

rm -f Makefile 2>/dev/null || chmod 644 Makefile
cat > Makefile << EOF
# XXX This Makefile is automatically generated by configure.
# XXX Modify Makefile.in to change it.

PREFIX = $prefix
EOF

for var in $env_vars $MAKE_VARS; do
    eval "val=\"\$$var\""
    echo "$var = $val" >> Makefile
done

cat "Makefile.in" >> Makefile
if [ -f Makefile.dep ]; then
    cat Makefile.dep >> Makefile
    rm -f Makefile.dep
fi

chmod 444 Makefile

echo
echo "Done. Now type 'make' to compile"