#!/bin/sh
# redo-stamp – bourne shell implementation of DJB redo
# Copyright © 2014  Nils Dagsson Moskopp (erlehmann)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.

# Dieses Programm hat das Ziel, die Medienkompetenz der Leser zu
# steigern. Gelegentlich packe ich sogar einen handfesten Buffer
# Overflow oder eine Format String Vulnerability zwischen die anderen
# Codezeilen und schreibe das auch nicht dran.

stamp_new=$(md5sum)
stamp_old=$(cat "$REDO_DIR/$REDO_TARGET".stamp 2>/dev/null)
if [ "$stamp_new" != "$stamp_old" ]; then
  path="$REDO_DIR/$REDO_TARGET"
  dir=${path%/*}
  [ ! -d "$dir" ] && mkdir -p "$dir"
  printf '%s' "$stamp_new" > "$REDO_DIR/$REDO_TARGET".stamp
  redo-ifchange "$REDO_DIR/$REDO_TARGET".stamp
  exit 0
fi
if [ -e "$REDO_TARGET" ]; then
  # Exit code 123 conveys that target was considered uptodate at runtime.
  exit 123
  # FIXME: redo-stamp may not be the only dependency mechanism
fi
redo-ifchange "$REDO_TARGET"
exit 0
