base/ref_counted.cc

// Copyright 2008, Google Inc.
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#include "base/ref_counted.h"

#include "base/logging.h"

namespace base {

namespace subtle {

RefCountedBase::RefCountedBase() : ref_count_(0) {
#ifndef NDEBUG
  in_dtor_ = false;
#endif
}

RefCountedBase::~RefCountedBase() {
#ifndef NDEBUG
  DCHECK(in_dtor_) << "RefCounted object deleted without calling Release()";
#endif
}

void RefCountedBase::AddRef() {
#ifndef NDEBUG
  DCHECK(!in_dtor_);
#endif
  ++ref_count_;
}

bool RefCountedBase::Release() {
#ifndef NDEBUG
  DCHECK(!in_dtor_);
#endif
  if (--ref_count_ == 0) {
#ifndef NDEBUG
    in_dtor_ = true;
#endif
    return true;
  }
  return false;
}

RefCountedThreadSafeBase::RefCountedThreadSafeBase() : ref_count_(0) {
#ifndef NDEBUG
  in_dtor_ = false;
#endif
}

RefCountedThreadSafeBase::~RefCountedThreadSafeBase() {
#ifndef NDEBUG
  DCHECK(in_dtor_) << "RefCountedThreadSafe object deleted without "
                      "calling Release()";
#endif
}

void RefCountedThreadSafeBase::AddRef() {
#ifndef NDEBUG
  DCHECK(!in_dtor_);
#endif
  AtomicRefCountInc(&ref_count_);
}

bool RefCountedThreadSafeBase::Release() {
#ifndef NDEBUG
  DCHECK(!in_dtor_);
  DCHECK(!AtomicRefCountIsZero(&ref_count_));
#endif
  if (!AtomicRefCountDec(&ref_count_)) {
#ifndef NDEBUG
    in_dtor_ = true;
#endif
    return true;
  }
  return false;
}

}  // namespace subtle

}  // namespace base