test_Fifo.cxx

Go to the documentation of this file.

// Copyright 2019-2020 CERN and copyright holders of ALICE O2.
// See https://alice-o2.web.cern.ch/copyright for details of the copyright holders.
// All rights not expressly granted are reserved.
//
// This software is distributed under the terms of the GNU General Public
// License v3 (GPL Version 3), copied verbatim in the file "COPYING".
//
// In applying this license CERN does not waive the privileges and immunities
// granted to it by virtue of its status as an Intergovernmental Organization
// or submit itself to any jurisdiction.
 
 
#define BOOST_TEST_MODULE Utility test
#define BOOST_TEST_MAIN
#define BOOST_TEST_DYN_LINK
#include <boost/test/unit_test.hpp>
#include "Fifo.h"
#include <iostream>
#include <iomanip>
#include <unistd.h>
#include <thread>
 
const int nEvents = 6;
const int sleepTime = 1;
 
template <typename T>
bool processValue(T value)
{
  std::cout << "processing " << value << std::endl;
  sleep(sleepTime);
  return (value + 1 < nEvents);
}
 
template <class FifoT, typename T>
void pushFifo(FifoT& fifo, T value = FifoT::value_type)
{
  std::cout << "pushing " << value << std::endl;
  fifo.push(value);
}
 
BOOST_AUTO_TEST_CASE(test_Fifo)
{
  using value_type = unsigned int;
  o2::test::Fifo<value_type> fifo;
 
  // start a consumer thread which pulls from the FIFO to the function
  // processValue with a simulated prcessing of one second.
  std::thread consumer([&fifo]() {
    do {
    } while (fifo.pull([](value_type v) { return processValue(v); }));
  });
 
  // fill some values into the FIFO which the consumer can process
  // immediately
  unsigned int value = 0;
  pushFifo(fifo, value++);
  pushFifo(fifo, value++);
  pushFifo(fifo, value++);
 
  // now continue filling with a period longer than the consumer
  // processing, consumer and producer are in sync once consumer
  // has processed events which have been added to the FIFO before
  while (value < nEvents) {
    sleep(2 * sleepTime);
    pushFifo(fifo, value++);
  }
 
  consumer.join();
}