Method loadClassifiers

plugins/cachekey/configs.cc:280–366

* @brief a helper function which loads the classifier from files. * @param args classname + filename in ' : ' format. * @param denylist true - load as a denylist classifier, false - allowlist. * @return true if successful, false otherwise. */

 * @return true if successful, false otherwise.
 */
bool
Configs::loadClassifiers(const String &args, bool denylist)
{
  static const char *EXPECTED_FORMAT = "<classname>:<filename>";

  std::size_t d = args.find(':');
  if (String::npos == d) {
    CacheKeyError("failed to parse classifier string '%s', expected format: '%s'", optarg ? optarg : "null", EXPECTED_FORMAT);
    return false;
  }

  String classname(optarg, 0, d);
  String filename(optarg, d + 1, String::npos);

  if (classname.empty() || filename.empty()) {
    CacheKeyError("'<classname>' and '<filename>' in '%s' cannot be empty, expected format: '%s'", optarg ? optarg : "null",
                  EXPECTED_FORMAT);
    return false;
  }

  String path(makeConfigPath(filename));

  std::ifstream ifstr;
  String        regex;
  unsigned      lineno = 0;

  ifstr.open(path.c_str());
  if (!ifstr) {
    CacheKeyError("failed to load classifier '%s' from '%s'", classname.c_str(), path.c_str());
    return false;
  }

  MultiPattern *multiPattern;
  if (denylist) {
    multiPattern = new NonMatchingMultiPattern(classname);
  } else {
    multiPattern = new MultiPattern(classname);
  }
  if (nullptr == multiPattern) {
    CacheKeyError("failed to allocate classifier '%s'", classname.c_str());
    return false;
  }

  CacheKeyDebug("loading classifier '%s' from '%s'", classname.c_str(), path.c_str());

  while (std::getline(ifstr, regex)) {
    Pattern          *p;
    String::size_type pos;

    ++lineno;

    // Allow #-prefixed comments.
    pos = regex.find_first_of('#');
    if (pos != String::npos) {
      regex.resize(pos);
    }

    if (regex.empty()) {