make

# make - control the generation of executables and other files with rules
# A very essential build tool. Here, make is used to make make.
# https://www.gnu.org/software/make/

# base image
FROM alpine:edge as build

# install requirements
RUN apk add --no-cache gnupg gnupg-keyboxd build-base linux-headers curl jq tar xz # common base

# import gpg keys and trust them
COPY make.keys /gpgkeys
RUN gpg --import </gpgkeys && printf '%s:6:\n' \
  6D4EEB02AD834703510B117680CB727A20C79BB2 \
  3D2554F0A15338AB9AF1BB9D96B047156338B6D4 \
  | gpg --import-ownertrust

# download and verify latest sources
WORKDIR /download
ENV MIRROR="https://ftp.halifax.rwth-aachen.de/gnu/"
RUN curl -s "$MIRROR/make/" \
  | sed -n 's/.*href="make-\([0-9.]\+\)\.tar\.gz".*/\1/p' \
  | sort -rV | head -1 > VERSION \
  && export VERSION=$(cat VERSION) \
  && wget "$MIRROR/make/make-$VERSION.tar.gz" \
  && wget "$MIRROR/make/make-$VERSION.tar.gz.sig" \
  && gpg --verify *.sig

# extract sources
WORKDIR /build
RUN tar xf /download/*.tar.gz --strip-components=1

# compile binaries
ENV LDFLAGS="-Wl,-z,now -Wl,-z,relro -static -s" 
ENV CFLAGS="-fPIC -pie -fstack-protector-all -O2 -D_FORTIFY_SOURCE=2 -static -s"
RUN ./configure --prefix=/usr \
  && make -j$(nproc) \
  && (ldd make && exit 1 || true)

# copy sources to new stage
FROM scratch as sources
COPY --from=build /download /
COPY make /Dockerfile

# copy binaries to new stage
FROM scratch as binary
COPY --from=build /build/make /