ThreadPool.cxx

#include "ThreadPool.hpp"

// the constructor just launches some amount of workers
ThreadPool::ThreadPool(size_t threads)
  : stop(false)
{
  for(size_t i = 0; i<threads; ++i)
    workers.emplace_back([this] {
      for(;;) {
        std::packaged_task<void()> task;

        {
          std::unique_lock<std::mutex> lock(this->queue_mutex);
          this->condition.wait(lock,
            [this]{ return this->stop || !this->tasks.empty(); });
          if(this->stop && this->tasks.empty())
            return;
          task = std::move(this->tasks.front());
          this->tasks.pop();
        }

        task();
      }
    });
}

// the destructor joins all threads
ThreadPool::~ThreadPool() {
  {
    std::unique_lock<std::mutex> lock(queue_mutex);
    stop = true;
  }
  condition.notify_all();
  for(std::thread& worker : workers)
    worker.join();
}