Method run

gecode/search/par/dfs.hpp:161–299

   */
  template<class Tracer>
  void
  DFS<Tracer>::Worker::run(void) {
    /*
     * The engine maintains the following invariant:
     *  - If the current space (cur) is not nullptr, the path always points
     *    to exactly that space.
     *  - If the current space (cur) is nullptr, the path always points
     *    to the next space (if there is any).
     *
     * This invariant is needed so that no-goods can be extracted properly
     * when the engine is stopped or has found a solution.
     *
     */
    // Perform initial delay, if not first worker
    if (this != engine().worker(0))
      Support::Thread::sleep(Config::initial_delay);
    // Okay, we are in business, start working
    while (true) {
      switch (engine().cmd()) {
      case C_WAIT:
        // Wait
        engine().wait();
        break;
      case C_TERMINATE:
        // Acknowledge termination request
        engine().ack_terminate();
        // Wait until termination can proceed
        engine().wait_terminate();
        // Thread will be terminated by returning from run
        return;
      case C_RESET:
        // Acknowledge reset request
        engine().ack_reset_start();
        // Wait until reset has been performed
        engine().wait_reset();
        // Acknowledge that reset cycle is over
        engine().ack_reset_stop();
        break;
      case C_WORK:
        // Perform exploration work
        {
          m.acquire();
          if (idle) {
            m.release();
            // Try to find new work
            find();
          } else if (cur != nullptr) {
            start();
            if (stop(engine().opt())) {
              // Report stop
              m.release();
              engine().stop();
            } else {
              node++;
              SearchTracer::EdgeInfo ei;
              if (tracer) {
                if (path.entries() > 0) {
                  typename Path<Tracer>::Edge& top = path.top();