nsCycleCollectionTraversalCallback.h

Enable keyboard shortcuts

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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/. */

#ifndef nsCycleCollectionTraversalCallback_h__

#define nsCycleCollectionTraversalCallback_h__

#include <cstdint>

#include "nscore.h"

class nsCycleCollectionParticipant;

class nsISupports;

class JSObject;

namespace JS {

class GCCellPtr;

class NS_NO_VTABLE nsCycleCollectionTraversalCallback {

 public:

  // You must call DescribeRefCountedNode() with an accurate

  // refcount, otherwise cycle collection will fail, and probably crash.

  // If the callback cares about objname, it should put

  // WANT_DEBUG_INFO in mFlags.

  NS_IMETHOD_(void)

  DescribeRefCountedNode(nsrefcnt aRefcount, const char* aObjName) = 0;

  // Note, aCompartmentAddress is 0 if it is unknown.

  NS_IMETHOD_(void)

  DescribeGCedNode(bool aIsMarked, const char* aObjName,

                   uint64_t aCompartmentAddress = 0) = 0;

  NS_IMETHOD_(void) NoteXPCOMChild(nsISupports* aChild) = 0;

  NS_IMETHOD_(void) NoteJSChild(JS::GCCellPtr aThing) = 0;

  NS_IMETHOD_(void)

  NoteNativeChild(void* aChild, nsCycleCollectionParticipant* aHelper) = 0;

  NS_IMETHOD_(void)

  NoteWeakMapping(JSObject* aKey, nsISupports* aVal,

                  nsCycleCollectionParticipant* aValParticipant) = 0;

  // Give a name to the edge associated with the next call to

  // NoteXPCOMChild, NoteJSObject, NoteJSScript, or NoteNativeChild.

  // Callbacks who care about this should set WANT_DEBUG_INFO in the

  // flags.

  NS_IMETHOD_(void) NoteNextEdgeName(const char* aName) = 0;

  enum {

    // Values for flags:

    // Caller should call NoteNextEdgeName and pass useful objName

    // to DescribeRefCountedNode and DescribeGCedNode.

    WANT_DEBUG_INFO = (1 << 0),

    // Caller should not skip objects that we know will be

    // uncollectable.

    WANT_ALL_TRACES = (1 << 1)

};

  uint32_t Flags() const { return mFlags; }

  bool WantDebugInfo() const { return (mFlags & WANT_DEBUG_INFO) != 0; }

  bool WantAllTraces() const { return (mFlags & WANT_ALL_TRACES) != 0; }

 protected:

  nsCycleCollectionTraversalCallback() : mFlags(0) {}

  uint32_t mFlags;

};

#endif  // nsCycleCollectionTraversalCallback_h__