hphp/runtime/server/host-health-monitor.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef incl_HPHP_SERVER_MEMORY_PROTECTOR_H_
  18 #define incl_HPHP_SERVER_MEMORY_PROTECTOR_H_
  19
  20 #include <condition_variable>
  21 #include <memory>
  22 #include <mutex>
  23 #include <vector>
  24 #include <boost/container/flat_set.hpp>
  25
  26 #include "hphp/runtime/base/config.h"
  27 #include "hphp/util/async-func.h"
  28 #include "hphp/util/health-monitor-types.h"
  29
  30 namespace HPHP {
  31
  32 // This class must be used as a singleton.
  33 struct HostHealthMonitor {
  34   void subscribe(IHostHealthObserver* observer) {
  35     assert(observer != nullptr);
  36     std::lock_guard<std::mutex> g(m_lock);
  37     m_observers.insert(observer);
  38   }
  39   bool unsubscribe(IHostHealthObserver* observer) {
  40     std::lock_guard<std::mutex> g(m_lock);
  41     return !!m_observers.erase(observer);
  42   }
  43   void addMetric(IHealthMonitorMetric* metric);
  44
  45   void start();
  46   void stop();
  47   void waitForEnd();
  48
  49  private:
  50   HealthLevel evaluate();
  51   void notifyObservers(HealthLevel newStatus);
  52   void monitor();
  53
  54   std::vector<IHealthMonitorMetric*> m_metrics;
  55   boost::container::flat_set<IHostHealthObserver*> m_observers;
  56   std::mutex m_lock;                    // protects metrics/observers
  57   HealthLevel m_status{HealthLevel::Bold};
  58   std::mutex m_stopped_lock;
  59   std::condition_variable m_condition;
  60   bool m_stopped{true};
  61   std::unique_ptr<AsyncFunc<HostHealthMonitor>> m_monitor_func;
  62 };
  63
  64 }
  65
  66 #endif