gecko-dev/xpcom/glue/nsCycleCollectionNoteChild.h

89 строки
3.0 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
// This header will be included by headers that define refpointer and array classes
// in order to specialize CC helpers such as ImplCycleCollectionTraverse for them.
#ifndef nsCycleCollectionNoteChild_h__
#define nsCycleCollectionNoteChild_h__
#include "nsCycleCollectionTraversalCallback.h"
#include "mozilla/Likely.h"
#include "mozilla/TypeTraits.h"
enum {
CycleCollectionEdgeNameArrayFlag = 1
};
// Just a helper for appending "[i]". Didn't want to pull in string headers here.
void
CycleCollectionNoteEdgeNameImpl(nsCycleCollectionTraversalCallback& aCallback,
const char* aName,
uint32_t aFlags = 0);
// Should be inlined so that in the no-debug-info case this is just a simple if().
MOZ_ALWAYS_INLINE void
CycleCollectionNoteEdgeName(nsCycleCollectionTraversalCallback& aCallback,
const char* aName,
uint32_t aFlags = 0)
{
if (MOZ_UNLIKELY(aCallback.WantDebugInfo())) {
CycleCollectionNoteEdgeNameImpl(aCallback, aName, aFlags);
}
}
#define NS_CYCLE_COLLECTION_INNERCLASS \
cycleCollection
#define NS_CYCLE_COLLECTION_INNERNAME \
_cycleCollectorGlobal
#define NS_CYCLE_COLLECTION_PARTICIPANT(_class) \
_class::NS_CYCLE_COLLECTION_INNERCLASS::GetParticipant()
template <typename T>
nsISupports* ToSupports(T* p, typename T::NS_CYCLE_COLLECTION_INNERCLASS* dummy = 0)
{
return T::NS_CYCLE_COLLECTION_INNERCLASS::Upcast(p);
}
// The default implementation of this class template is empty, because it
// should never be used: see the partial specializations below.
template <typename T,
bool IsXPCOM = mozilla::IsBaseOf<nsISupports, T>::value>
struct CycleCollectionNoteChildImpl
{
};
template <typename T>
struct CycleCollectionNoteChildImpl<T, true>
{
static void Run(nsCycleCollectionTraversalCallback& aCallback, T* aChild)
{
aCallback.NoteXPCOMChild(ToSupports(aChild));
}
};
template <typename T>
struct CycleCollectionNoteChildImpl<T, false>
{
static void Run(nsCycleCollectionTraversalCallback& aCallback, T* aChild)
{
aCallback.NoteNativeChild(aChild, NS_CYCLE_COLLECTION_PARTICIPANT(T));
}
};
template <typename T>
inline void CycleCollectionNoteChild(nsCycleCollectionTraversalCallback& aCallback,
T* aChild,
const char* aName,
uint32_t aFlags = 0)
{
CycleCollectionNoteEdgeName(aCallback, aName, aFlags);
CycleCollectionNoteChildImpl<T>::Run(aCallback, aChild);
}
#endif // nsCycleCollectionNoteChild_h__