amxmodx/public/amtl/am-refcounting-threadsafe.h

// vim: set sts=8 ts=2 sw=2 tw=99 et:
//
// Copyright (C) 2013, David Anderson and AlliedModders LLC
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// 
//  * Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
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//    this list of conditions and the following disclaimer in the documentation
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#ifndef _include_amtl_ts_refcounting_h_
#define _include_amtl_ts_refcounting_h_

#include <am-refcounting.h>
#include <am-atomics.h>

namespace ke {

// See the comment above Refcounted<T> for more information. This class is
// identical, except changing the reference count is guaranteed to be atomic
// with respect to other threads changing the reference count.
template <typename T>
class RefcountedThreadsafe
{
  public:
    RefcountedThreadsafe()
     : refcount_(0)
    {
    }

    void AddRef() {
      refcount_.increment();
    }
    bool Release() {
        if (!refcount_.decrement()) {
            delete static_cast<T *>(this);
            return false;
        }
        return true;
    }

  protected:
    ~RefcountedThreadsafe() {
    }

  private:
    AtomicRefCount refcount_;
};

} // namespace ke

#endif // _include_amtl_ts_refcounting_h_