concurrency_limit_test.cc

#include "concurrency_limit.h"

#include <unistd.h>
#include <cassert>
#include <future>
#include <iostream>
#include <mutex>
#include <string>
#include <vector>

using std::async;
using std::cout;
using std::endl;
using std::future;
using std::lock_guard;
using std::mutex;
using std::vector;

void TestAsync() {
  int counter = 0;
  std::mutex m{};
  {
    vector<future<void> > jobs;

    // 20 iterations should finish in about 3 beats
    for (int i = 0; i < 20; ++i) {
      jobs.emplace_back(async([i, &m, &counter] {
        char buffer[20];
        sprintf(buffer, "task %i", i);
        ScopedConcurrencyLimit l(buffer);
        // sleep for a quaver
        usleep(250000);
        {
          lock_guard<mutex> l(m);
          counter++;
        }
      }));
    }
  }

  assert(counter == 20);
}

int main(int argc, char** argv) { TestAsync(); }