#!/bin/sh
# Start from the build image's prebuilt dependencies, then run the command.
# OxygenFlow's rust image holds this workspace's dependencies built at /src with
# this pipeline's environment (oxygenflow/images/rust, backlog F6b2); the
# job's target disk starts empty, so copying them in leaves cargo only this
# workspace's own crates to compile. Without them (an older image, or a
# failed copy) the job simply builds everything, as before.
set -eu
warm=/opt/warm/oxygen
# A fresh ext4 target disk holds only lost+found.
if [ -d "$warm" ] && [ -z "$(ls -A target 2>/dev/null | grep -vx 'lost+found')" ]; then
    start=$(date +%s)
    if cp -R --preserve=timestamps "$warm/." target/; then
        echo "flow: prebuilt dependencies copied in $(( $(date +%s) - start )) s"
    else
        echo "flow: could not copy the prebuilt dependencies; building them" >&2
        rm -rf target/* 2>/dev/null || true
    fi
fi
exec "$@"