function print_help {
	echo ""
	echo "Prepare environment for blackfinn-based yocto builds."
	echo ""
	echo "Usage:"
	echo "MACHINE=<my_machine> source blackfinn-init-build-env <build_dir>"
	echo ""
	echo "MACHINE is optional. if not specified it defaults to 'qemuarm-64'."
	echo "Supported machines:"
	echo -e "\tqemuarm\n\tqemuarm64\n\tqemumips\n\tqemumips64\n\tqemuppc"
	echo -e "\tqemux86\n\tqemux86-64\n"
	echo -e "\tbeaglebone-yocto\n\tedgerouter\n\tgenericx86\n\tgenericx86-64\n\tmpc8315e-rdb\n"
	echo -e "\traspberrypi3-64\n\tbananapi-m3"
	echo ""
	echo "<build_dir> is optional. If not specified it defaults to 'build'."
	echo ""
}

function print_config {
	echo "Configuration:"
	echo "      MACHINE: $1"
        echo "    BUILD_DIR: $2"
}


DEFAULT_MACHINE=qemux86-64
BUILD_DIR=build

print_help

if [ -z "$MACHINE" ]; then
	MACHINE=$DEFAULT_MACHINE
fi

if [ $# -eq "1" ]; then
	BUILD_DIR=$1
fi

print_config $MACHINE $BUILD_DIR

rm -f	build/conf/bblayers.conf \
	build/conf/templateconf.cfg

mkdir -p $BUILD_DIR

export TEMPLATECONF="../meta-blackfinn/buildconf/$MACHINE"

source layers/poky/oe-init-build-env $BUILD_DIR

return 0