#ifndef RefCounted_h
#define RefCounted_h
#include <wtf/Assertions.h>
#include <wtf/FastMalloc.h>
#include <wtf/Noncopyable.h>
namespace WTF {
#if defined(NDEBUG) && !ENABLE(SECURITY_ASSERTIONS)
#define CHECK_REF_COUNTED_LIFECYCLE 0
#else
#define CHECK_REF_COUNTED_LIFECYCLE 1
#endif
class RefCountedBase {
public:
void ref()
{
#if CHECK_REF_COUNTED_LIFECYCLE
ASSERT_WITH_SECURITY_IMPLICATION(!m_deletionHasBegun);
ASSERT(!m_adoptionIsRequired);
#endif
++m_refCount;
}
bool hasOneRef() const
{
#if CHECK_REF_COUNTED_LIFECYCLE
ASSERT(!m_deletionHasBegun);
#endif
return m_refCount == 1;
}
unsigned refCount() const
{
return m_refCount;
}
void relaxAdoptionRequirement()
{
#if CHECK_REF_COUNTED_LIFECYCLE
ASSERT_WITH_SECURITY_IMPLICATION(!m_deletionHasBegun);
ASSERT(m_adoptionIsRequired);
m_adoptionIsRequired = false;
#endif
}
protected:
RefCountedBase()
: m_refCount(1)
#if CHECK_REF_COUNTED_LIFECYCLE
, m_deletionHasBegun(false)
, m_adoptionIsRequired(true)
#endif
{
}
~RefCountedBase()
{
#if CHECK_REF_COUNTED_LIFECYCLE
ASSERT(m_deletionHasBegun);
ASSERT(!m_adoptionIsRequired);
#endif
}
bool derefBase()
{
#if CHECK_REF_COUNTED_LIFECYCLE
ASSERT_WITH_SECURITY_IMPLICATION(!m_deletionHasBegun);
ASSERT(!m_adoptionIsRequired);
#endif
ASSERT(m_refCount);
unsigned tempRefCount = m_refCount - 1;
if (!tempRefCount) {
#if CHECK_REF_COUNTED_LIFECYCLE
m_deletionHasBegun = true;
#endif
return true;
}
m_refCount = tempRefCount;
return false;
}
#if CHECK_REF_COUNTED_LIFECYCLE
bool deletionHasBegun() const
{
return m_deletionHasBegun;
}
#endif
private:
#if CHECK_REF_COUNTED_LIFECYCLE
friend void adopted(RefCountedBase*);
#endif
unsigned m_refCount;
#if CHECK_REF_COUNTED_LIFECYCLE
bool m_deletionHasBegun;
bool m_adoptionIsRequired;
#endif
};
#if CHECK_REF_COUNTED_LIFECYCLE
inline void adopted(RefCountedBase* object)
{
if (!object)
return;
ASSERT_WITH_SECURITY_IMPLICATION(!object->m_deletionHasBegun);
object->m_adoptionIsRequired = false;
}
#endif
template<typename T> class RefCounted : public RefCountedBase {
WTF_MAKE_NONCOPYABLE(RefCounted); WTF_MAKE_FAST_ALLOCATED;
public:
void deref()
{
if (derefBase())
delete static_cast<T*>(this);
}
protected:
RefCounted() { }
~RefCounted()
{
}
};
}
using WTF::RefCounted;
#endif // RefCounted_h