/*

 * This file is part of PowerDNS or dnsdist.

 * Copyright -- PowerDNS.COM B.V. and its contributors

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of version 2 of the GNU General Public License as

 * published by the Free Software Foundation.

 *

 * In addition, for the avoidance of any doubt, permission is granted to

 * link this program with OpenSSL and to (re)distribute the binaries

 * produced as the result of such linking.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 */

#include "dnsdist-configuration.hh"

#include "sholder.hh"

namespace dnsdist::configuration

{

static GlobalStateHolder<RuntimeConfiguration> s_currentRuntimeConfiguration;

static ImmutableConfiguration s_immutableConfiguration;

static std::atomic<bool> s_immutableConfigurationDone{false};

const RuntimeConfiguration& getCurrentRuntimeConfiguration()

{

  static thread_local auto t_threadLocalConfiguration = s_currentRuntimeConfiguration.getLocal();

  return *t_threadLocalConfiguration;

}

void updateRuntimeConfiguration(const std::function<void(RuntimeConfiguration&)>& mutator)

{

  s_currentRuntimeConfiguration.modify(mutator);

}

void updateImmutableConfiguration(const std::function<void(ImmutableConfiguration&)>& mutator)

{

  if (isImmutableConfigurationDone()) {

    throw std::runtime_error("Trying to update an immutable setting at runtime!");

  }

  mutator(s_immutableConfiguration);

}

const ImmutableConfiguration& getImmutableConfiguration()

{

  return s_immutableConfiguration;

}

bool isImmutableConfigurationDone()

{

  return s_immutableConfigurationDone.load();

}

void setImmutableConfigurationDone()

{

  if (s_immutableConfigurationDone.exchange(true)) {

    throw std::runtime_error("Trying to seal the runtime-immutable configuration a second time");

  }

}

}