afl-ptmin

#!/bin/sh

#   Copyright 2019 Federico Kircheis
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.

set -o errexit
set -o nounset

findnonemptyfiles0(){
  find "$1" -type f ! -size 0 -printf '%f\0';
}

# FIXME: does it work if filename contains '{}'?
parallel_tmin0(){
  IN="$1"; shift;
  OUT="$1"; shift;
  if command -v parallel > /dev/null 2>&1; then :;
    parallel -0 afl-tmin -i "$IN/{}" -o "$OUT/{}" "$@";
  else :; # fallback, xargs is always avaiable, right?
    printf 'parallel not available, falling back to xargs\n' >&2;
    xargs -0 -P "$(grep -c processor /proc/cpuinfo)" -I '{}' afl-tmin -i "$IN/{}" -o "$OUT/{}" "$@";
  fi
}

tmin_dir(){
  in="$1"; shift;
  out="$1"; shift;
  if [ ! -d "$out" ]; then :;
    mkdir "$out";
  fi
  # empty files handled separately, maybe not necessary anymore
  find "$in" -type f -size 0 -printf '%f\0' | xargs -0 -I '{}' touch "$out/{}";
  findnonemptyfiles0 "$in" | parallel_tmin0 "$in" "$out" "$@";
}

help(){
  # FIXME: afl-tmin exits with error
  afl-tmin 2>&1 | sed -e '${/^$/d;}' \
                      -e '1s;^;afl-ptmin, based on ;' -e '3s;afl-tmin;afl-ptmin;' \
                      -e 's;-i file;-i dir ;' -e 's;-o file;-o dir ;' \
                      ;
}

is_help_param(){
  [ "$1" = "-h" ] || [ "$1" = "--help" ] || [ "$1" = "h" ] || [ "$1" = "help" ] || [ "$1" = "?" ];
}

main(){
  unset AFL_PTMIN_IN
  unset AFL_PTMIN_OU
  [ $# -eq 0 ] && set -- "$@" '?';

  NEXT_IS_AFL_PTMIN_IN=false;
  NEXT_IS_AFL_PTMIN_OU=false;
  PARSE=true;
  for key in "$@"; do :;
    shift
    if ! $PARSE; then :;
      set -- "$@" "$key";
    else
      if   $NEXT_IS_AFL_PTMIN_IN; then :;
        AFL_PTMIN_IN="$key"; NEXT_IS_AFL_PTMIN_IN=false;
      elif $NEXT_IS_AFL_PTMIN_OU; then :;
        AFL_PTMIN_OU="$key"; NEXT_IS_AFL_PTMIN_OU=false;
      elif [ "$key" = "-i" ]; then :;
        NEXT_IS_AFL_PTMIN_IN=true;
      elif [ "$key" = "-o" ]; then :;
        NEXT_IS_AFL_PTMIN_OU=true;
      elif is_help_param "$key"; then :;
        help;
        exit 0;
      else
        set -- "$@" "$key";
      fi
      if [ "$key" = "--" ]; then :;
        PARSE=false;
      fi
    fi
  done

  if   [ ! -n "${AFL_PTMIN_IN+x}" ]; then :;
    printf 'Missing input directory\n'  >&2; exit 1;
  elif [ ! -n "${AFL_PTMIN_IN+x}" ] ; then :;
    printf 'Missing output directory\n' >&2; exit 1;
  fi
  tmin_dir "$AFL_PTMIN_IN" "$AFL_PTMIN_OU" "$@";
}

main "$@";

# consider alternative design: add option to afl to enable/disable parallel processing