base/refcountedobject.h.pump

/*
 *  Copyright 2016 The WebRTC Project Authors. All rights reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

// To generate refcount.h from refcount.h.pump, execute:
// ./testing/gtest/scripts/pump.py ./webrtc/base/refcountedobject.h.pump

#ifndef WEBRTC_BASE_REFCOUNTEDOBJECT_H_
#define WEBRTC_BASE_REFCOUNTEDOBJECT_H_

#include <utility>

#include "webrtc/base/atomicops.h"

namespace rtc {

template <class T>
class RefCountedObject : public T {
 public:
  RefCountedObject() {}

  $range i 0..10
  $for i [[
  $range j 0..i
  template <$for j , [[class P$j]]>
  $if i == 0 [[explicit ]]
  RefCountedObject($for j , [[P$j&& p$j]]) : T($for j , [[std::forward<P$j>(p$j)]]) {}
  ]]

  virtual int AddRef() const { return AtomicOps::Increment(&ref_count_); }

  virtual int Release() const {
    int count = AtomicOps::Decrement(&ref_count_);
    if (!count) {
      delete this;
    }
    return count;
  }

  // Return whether the reference count is one. If the reference count is used
  // in the conventional way, a reference count of 1 implies that the current
  // thread owns the reference and no other thread shares it. This call
  // performs the test for a reference count of one, and performs the memory
  // barrier needed for the owning thread to act on the object, knowing that it
  // has exclusive access to the object.
  virtual bool HasOneRef() const {
    return AtomicOps::AcquireLoad(&ref_count_) == 1;
  }

 protected:
  virtual ~RefCountedObject() {}

  mutable volatile int ref_count_ = 0;
};

}  // namespace rtc

#endif  // WEBRTC_BASE_REFCOUNTEDOBJECT_H_