third_party/WebKit/Source/platform/InstanceCounters.h

/*
* Copyright (C) 2012 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
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* notice, this list of conditions and the following disclaimer.
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* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
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*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef InstanceCounters_h
#define InstanceCounters_h

#include "platform/PlatformExport.h"
#include "wtf/Allocator.h"
#include "wtf/Atomics.h"

namespace blink {

class InstanceCounters {
  STATIC_ONLY(InstanceCounters);

 public:
  enum CounterType {
    ActiveDOMObjectCounter,
    AudioHandlerCounter,
    DocumentCounter,
    FrameCounter,
    JSEventListenerCounter,
    LayoutObjectCounter,
    NodeCounter,
    ResourceCounter,
    ScriptPromiseCounter,
    V8PerContextDataCounter,
    WorkerGlobalScopeCounter,

    // This value must be the last.
    CounterTypeLength,
  };

  static inline void incrementCounter(CounterType type) {
    DCHECK_NE(type, NodeCounter);
    atomicIncrement(&s_counters[type]);
  }

  static inline void decrementCounter(CounterType type) {
    DCHECK_NE(type, NodeCounter);
    atomicDecrement(&s_counters[type]);
  }

  static inline void incrementNodeCounter() {
    DCHECK(isMainThread());
    s_nodeCounter++;
  }

  static inline void decrementNodeCounter() {
    DCHECK(isMainThread());
    s_nodeCounter--;
  }

  PLATFORM_EXPORT static int counterValue(CounterType);

 private:
  PLATFORM_EXPORT static int s_counters[CounterTypeLength];
  PLATFORM_EXPORT static int s_nodeCounter;
};

}  // namespace blink

#endif  // !defined(InstanceCounters_h)