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#ifndef GRPC_INTERNAL_CPP_SERVER_THREAD_POOL_H
#define GRPC_INTERNAL_CPP_SERVER_THREAD_POOL_H

#include <grpc++/config.h>
#include <grpc++/thread_pool_interface.h>

#include <condition_variable>
#include <thread>
#include <mutex>
#include <queue>
#include <vector>

namespace grpc {

class ThreadPool GRPC_FINAL : public ThreadPoolInterface {
 public:
  explicit ThreadPool(int num_threads);
  ~ThreadPool();

  void ScheduleCallback(const std::function<void()>& callback) GRPC_OVERRIDE;

 private:
  std::mutex mu_;
  std::condition_variable cv_;
  bool shutdown_;
  std::queue<std::function<void()>> callbacks_;
  std::vector<std::thread> threads_;

  void ThreadFunc();
};

}  // namespace grpc

#endif  // GRPC_INTERNAL_CPP_SERVER_THREAD_POOL_H