FROM alpine:3.22 AS build

RUN apk add --no-cache \
    build-base \
    bison \
    flex \
    linux-headers \
    file \
    binutils \
    tar

WORKDIR /src

ARG UBOOT_TAR
ARG UBOOT_VERSION

COPY ${UBOOT_TAR} /tmp/
RUN tar zxf "/tmp/$(basename "${UBOOT_TAR}")"

RUN make tools-only_defconfig

# Build the env tools using the supported target.
RUN make -j"$(nproc)" \
    HOSTCC=gcc \
    HOSTLD=gcc \
    HOSTCFLAGS='-O2' \
    HOSTLDFLAGS='-static' \
    envtools

# fw_setenv is the same program; create the link ourselves.
RUN ln -sf fw_printenv tools/env/fw_setenv

RUN file tools/env/fw_printenv tools/env/fw_setenv

RUN readelf -d tools/env/fw_printenv || true

RUN ! readelf -d tools/env/fw_printenv | grep -q '(NEEDED)'

FROM scratch AS export
COPY --from=build /src/tools/env/fw_printenv /fw_printenv
COPY --from=build /src/tools/env/fw_setenv /fw_setenv