stargazing/auto-update

#!/usr/bin/env sh

note() { printf >&2 '\033[1m%s\033[0m\n' "$*" ;}

latest() { : \
 && url="${1?missing argument}" \
 &&  {  [ "${url#"https://github.com/"}" = "$url" ] \
     && re='/commit/' || re='/spoofed_commit_check/' \
     ;} \
 && curl $flags "$url" | grep -F "$re" | grep -Eo '[0-9a-f]{40}' \
 ;}

any=0 flags="-L --no-progress-meter" n="$(printf '\n.')" n="${n%.}" \
df=Dockerfile gh='https://github.com/' sr='https://git.sr.ht/~' \
 && set -- \
    cosmo           COSMO_COMMIT    ${gh}jart/cosmopolitan \
    cosmo-kuroko    KUROKO_COMMIT   ${gh}kuroko-lang/kuroko \
    cosmo-muon      MUON_COMMIT     ${sr}lattis/muon \
    cosmo-perl      PERL_COMMIT     ${gh}G4Vi/perl5/tree/cosmo \
    cosmo-python    PYTHON_COMMIT   ${gh}ahgamut/cpython/tree/cosmo_py311 \
    cosmo-yices     KISSAT_COMMIT   ${gh}BrunoDutertre/kissat \
    cosmo-yices     YICES_COMMIT    ${gh}SRI-CSL/yices2 \
 && me="$(readlink -f "$0")" && cd "${me%/*}" \
 && while [ $# != 0 ] \
    ;do dir="$1" tag="$2" url="$3" \
     && { shift && shift && shift || { note 'incomplete triplet'; exit 70 ;} ;} \
     &&  {  [ -d "$dir" ] && [ -f "$dir/$df" ] && [ -s "$dir/$df" ] \
         || { note "missing $df, skipping $dir ($tag)"; continue ;} \
         ;} \
     && grep -Fq "$tag=" "$dir/$df" \
     && ours="$(grep -F "$tag=" "$dir/$df" | cut -d= -f2-)" \
     && theirs="$(latest "$url")" ours="${ours%%$n*}" theirs="${theirs%%$n*}" \
     &&  if [ ${#theirs} = 0 ] \
        ;then note "failed to retrieve update for $dir ($tag)" \
        ;elif [ "$ours" != "$theirs" ] \
        ;then any=1 && note "updating $dir ($tag)" \
         && other="${tag%_COMMIT}_SHA256" && tgz="${url%/}" \
         && tgz="${tgz%%/tree/*}" && tgz="$tgz/archive/$theirs.tar.gz" \
         &&  {  sum="$(curl $flags "$tgz" | sha256sum - | awk '{print $1}')" \
             && notwa-util/shed "$dir/$df" "s/$tag=$ours/$tag=$theirs/g" \
             && notwa-util/shed "$dir/$df" "s/$other=.*/$other=$sum/g" \
             ;} \
         || note "failed to apply update for $dir ($tag)" \
        ;fi \
     || note "failed to determine update for $dir ($tag)" \
    ;done \
 && { [ $any = 1 ] || note "no new updates" ;} \
;