sequence_barrier.h

// Copyright (c) 2011-2015, Francois Saint-Jacques
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright
//       notice, this list of conditions and the following disclaimer in the
//       documentation and/or other materials provided with the distribution.
//     * Neither the name of the disruptor-- nor the
//       names of its contributors may be used to endorse or promote products
//       derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL FRANCOIS SAINT-JACQUES BE LIABLE FOR ANY
// DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef DISRUPTOR_SEQUENCE_BARRIER_H_  // NOLINT
#define DISRUPTOR_SEQUENCE_BARRIER_H_  // NOLINT

#include <memory>
#include <vector>

#include "disruptor/wait_strategy.h"
#include "disruptor/sequence.h"

namespace disruptor {

template <typename W = kDefaultWaitStrategy>
class SequenceBarrier {
 public:
  SequenceBarrier(const Sequence& cursor,
                  const std::vector<Sequence*>& dependents)
      : cursor_(cursor), dependents_(dependents), alerted_(false) {}

  int64_t WaitFor(const int64_t& sequence) {
    return wait_strategy_.WaitFor(sequence, cursor_, dependents_, alerted_);
  }

  template <class R, class P>
  int64_t WaitFor(const int64_t& sequence,
                  const std::chrono::duration<R, P>& timeout) {
    return wait_strategy_.WaitFor(sequence, cursor_, dependents_, alerted_,
                                  timeout);
  }

  int64_t get_sequence() const { return cursor_.sequence(); }

  bool alerted() const {
    return alerted_.load(std::memory_order::memory_order_acquire);
  }

  void set_alerted(bool alert) {
    alerted_.store(alert, std::memory_order::memory_order_release);
  }

 private:
  W wait_strategy_;
  const Sequence& cursor_;
  std::vector<Sequence*> dependents_;
  std::atomic<bool> alerted_;
};

};  // namespace disruptor

#endif  // DISRUPTOR_DEPENDENCY_BARRIER_H_ NOLINT