Function EnvAppend

be/src/rpc/authentication.cc:1325–1354

For the environment variable attr, append "-Dthing=thingval" if "thing" is not already in the current attr's value.

// For the environment variable attr, append "-Dthing=thingval" if "thing" is not already
// in the current attr's value.
static Status EnvAppend(const string& attr, const string& thing, const string& thingval) {
  // Carefully append to attr. There are three distinct cases:
  // 1. Attr doesn't exist: set it
  // 2. Attr exists, and doesn't contain thing: append to it
  // 3. Attr exists, and already contains thing: do nothing
  string current_val;
  char* current_val_c = getenv(attr.c_str());
  if (current_val_c != NULL) {
    current_val = current_val_c;
  }

  if (!current_val.empty() && (current_val.find(thing) != string::npos)) {
    // Case 3 above
    return Status::OK();
  }

  stringstream val_out;
  if (!current_val.empty()) {
    // Case 2 above
    val_out << current_val << " ";
  }
  val_out << "-D" << thing << "=" << thingval;

  if (setenv(attr.c_str(), val_out.str().c_str(), 1) < 0) {
    return Status(Substitute("Bad $0=$1 value: Could not set environment variable $2: $3",
        thing, thingval, attr, GetStrErrMsg()));
  }

  return Status::OK();
}

Status AuthManager::InitKerberosEnv() {
  if (IsKerberosEnabled()) {