#!/bin/sh
set -eu

# From: https://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/eclass/multiprocessing.eclass
makeopts_jobs() {
    # This assumes the first .* will be more greedy than the second .*
    # since POSIX doesn't specify a non-greedy match (i.e. ".*?").
    local jobs=$(echo " $MAKEFLAGS " | sed -r -n \
        -e 's:.*[[:space:]](-j|--jobs[=[:space:]])[[:space:]]*([0-9]+).*:\2:p' \
        -e 's:.*[[:space:]](-j|--jobs)[[:space:]].*:999:p')
    echo ${jobs:-1}
}

version_jdk11=11.0.5+6

dir_download="$PWD/download"
mkdir -p build; cd build
dir_install="$PWD/install-jdk11"

# Prepare source
tar xf "$dir_download/jdk11u-jdk-$version_jdk11.tar.bz2"
cd "jdk11u-jdk-$version_jdk11"
chmod +x configure

# Configure source
./configure \
    --prefix="$dir_install" \
    --with-boot-jdk="$PWD/../install-jdk10" \
    --with-jobs="$(makeopts_jobs)" \
    --disable-full-docs \
    --enable-headless-only \
    --disable-warnings-as-errors

# Build and install
unset MAKEFLAGS
make product-images
make install