ceph/src/dmclock/support/src/run_every.h

   1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
   2 // vim: ts=8 sw=2 smarttab
   3 /*
   4  * Copyright (C) 2017 Red Hat Inc.
   5  */
   6
   7
   8 #pragma once
   9
  10 #include <chrono>
  11 #include <mutex>
  12 #include <condition_variable>
  13 #include <thread>
  14 #include <functional>
  15
  16 namespace crimson {
  17   using std::chrono::duration_cast;
  18   using std::chrono::milliseconds;
  19
  20   // runs a given simple function object waiting wait_period
  21   // milliseconds between; the destructor stops the other thread
  22   // immediately
  23   class RunEvery {
  24     using Lock      = std::unique_lock<std::mutex>;
  25     using Guard     = std::lock_guard<std::mutex>;
  26     using TimePoint = std::chrono::steady_clock::time_point;
  27
  28     bool                      finishing = false;
  29     std::chrono::milliseconds wait_period;
  30     std::function<void()>     body;
  31     std::mutex                mtx;
  32     std::condition_variable   cv;
  33
  34     // put threads last so all other variables are initialized first
  35
  36     std::thread               thd;
  37
  38   public:
  39
  40 #ifdef ADD_MOVE_SEMANTICS
  41     RunEvery();
  42 #endif
  43
  44     template<typename D>
  45     RunEvery(D                     _wait_period,
  46              std::function<void()> _body) :
  47       wait_period(duration_cast<milliseconds>(_wait_period)),
  48       body(_body)
  49     {
  50       thd = std::thread(&RunEvery::run, this);
  51     }
  52
  53     RunEvery(const RunEvery& other) = delete;
  54     RunEvery& operator=(const RunEvery& other) = delete;
  55     RunEvery(RunEvery&& other) = delete;
  56 #ifdef ADD_MOVE_SEMANTICS
  57     RunEvery& operator=(RunEvery&& other);
  58 #else
  59     RunEvery& operator=(RunEvery&& other) = delete;
  60 #endif
  61
  62     ~RunEvery();
  63
  64     void join();
  65
  66   protected:
  67
  68     void run();
  69   };
  70 }