cef_ref_counted.h File Reference

#include <stddef.h>
#include <utility>
#include "include/base/cef_atomic_ref_count.h"
#include "include/base/cef_build.h"
#include "include/base/cef_compiler_specific.h"
#include "include/base/cef_logging.h"
#include "include/base/cef_scoped_refptr.h"
#include "include/base/cef_thread_checker.h"

Classes
struct	base::DefaultRefCountedTraits< T >
	Default traits for RefCounted<T>. More...
class	base::RefCounted< T, Traits >
	A base class for reference counted classes. More...
struct	base::DefaultRefCountedThreadSafeTraits< T >
	Default traits for RefCountedThreadSafe<T>. More...
class	base::RefCountedThreadSafe< T, Traits >
	A thread-safe variant of RefCounted<T> More...
class	base::RefCountedData< T >
	A thread-safe wrapper for some piece of data so we can place other things in scoped_refptrs<>. More...

Namespaces
	base

Macros
#define	REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE()
	The reference count starts from zero by default, and we intended to migrate to start-from-one ref count. More...

Typedefs
using	base::ScopedAllowCrossThreadRefCountAccess = cef_subtle::ScopedAllowCrossThreadRefCountAccess

Functions
template<typename T >
bool	base::operator== (const RefCountedData< T > &lhs, const RefCountedData< T > &rhs)
template<typename T >
bool	base::operator!= (const RefCountedData< T > &lhs, const RefCountedData< T > &rhs)

Macro Definition Documentation

REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE

#define REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE

(

)

Value:

  static constexpr ::base::cef_subtle::StartRefCountFromOneTag \
      kRefCountPreference = ::base::cef_subtle::kStartRefCountFromOneTag

The reference count starts from zero by default, and we intended to migrate to start-from-one ref count.

Put REQUIRE_ADOPTION_FOR_REFCOUNTED_TYPE() to the ref counted class to opt-in.

If an object has start-from-one ref count, the first scoped_refptr need to be created by base::AdoptRef() or base::MakeRefCounted(). We can use base::MakeRefCounted() to create create both type of ref counted object.

The motivations to use start-from-one ref count are:

• Start-from-one ref count doesn't need the ref count increment for the first reference.
• It can detect an invalid object acquisition for a being-deleted object that has zero ref count. That tends to happen on custom deleter that delays the deletion. TODO(tzik): Implement invalid acquisition detection.
• Behavior parity to Blink's WTF::RefCounted, whose count starts from one. And start-from-one ref count is a step to merge WTF::RefCounted into base::RefCounted.