configure

#!/bin/sh -e

BIN_DEPS="mkdir rm cat sed cp chmod"

DUMPINTERVAL=60
PREFIX=/opt/piranha
DEBUG=0
VERBOSE=0
CONFIG=".config.mk"

find_exec()
{
	EXE=`which $1 2>/dev/null`
}

usage()
{
	printf "Usage %s [--debug] [--verbose] [--prefix=</path/to/piranha>] [--dumpint=<seconds>] [--help]\n" $1
	printf "  --help    : show help\n"
	printf "  --debug   : enable debug code\n"
	printf "  --verbose : enable verbose compilation\n"
	printf "  --prefix  : set base installation directory (default: /opt/piranha)\n"
	printf "  --dumpint : set dump interval in seconds (default: 60)\n"
	exit 0
}

onoff()
{
	if [ $1 -eq 1 ]
	then
		onoff="enabled"
	else
		onoff="disabled"
	fi
}

show_conf()
{
	printf "Piranha configuration script\n"
	printf "\n"
	printf "Detected Arch       : %s\n" ${ARCH}
	printf "Detected OS         : %s %s\n" ${OS} ${OSVER}
	printf "Detected Compiler   : %s\n" ${CC}
	printf "Installation prefix : %s\n" ${PREFIX}
	onoff ${DEBUG}
	printf "Debug code          : %s\n" ${onoff}
	onoff ${VERBOSE}
	printf "Verbose compilation : %s\n" ${onoff}
	printf "\n"
}

write_conf()
{
	rm -f ${CONFIG}
	for NAME in ARCH OS OSVER PREFIX DEBUG VERBOSE CC CCNAME DUMPINTERVAL
	do
		VALUE=`eval echo "\\$${NAME}"`
		printf "%s=%s\n" ${NAME} ${VALUE} >> ${CONFIG}
	done

	for EXE in ${BIN_DEPS}
	do
		NAME=`echo ${EXE} | tr [:lower:] [:upper:]`
		find_exec ${EXE}
		if [ -z "${EXE}" ]
		then
			printf "ERROR: Failed to locate '%s'\n" ${NAME}
			exit 1;
		fi
		printf "%s=%s\n" ${NAME} ${EXE} >> ${CONFIG}
	done
}

detect_os()
{
	OS=`uname -s | tr [a-z] [A-Z]`
	OSVER=`uname -r`
	ARCH=`uname -m`
	CCNAME="GCC"
	find_exec "gcc"
	if [ -z "${EXE}" ]
	then
		find_exec "cc"
		CCNAME="CC"
	fi
	CC=${EXE}

	if [ -z "$CC" ]
	then
		printf "ERROR: Failed to locate gcc/ccn\n"
		exit 1;
	fi
}

for arg in "$@"
do
	case $arg in
		--prefix=*)
		PREFIX=`echo -- "$arg" | awk -F= '{print $2}'`
		;;
		--dumpint=*)
		DUMPINTERVAL=`echo -- "$arg" | awk -F= '{print $2}'`
		echo "$DUMPINTERVAL" | egrep -q '^[0-9]+$' || { echo "ERROR: dump interval must be a number"; exit 1; }
		echo "$DUMPINTERVAL" | egrep -q '^0$' && { echo "ERROR: dump interval cannot be 0"; exit 1; }
		;;
		--verbose)
		VERBOSE=1
		;;
		--debug)
		DEBUG=1
		;;
		--help)
			usage $0
		;;
		*)
			printf "Unknown argument '%s'\n" $arg
			exit 1
		;;
	esac
done

detect_os
show_conf
write_conf