gecko-dev/xpcom/base/nsCycleCollector.h

/* -*- 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 nsCycleCollector_h__
#define nsCycleCollector_h__

class nsICycleCollectorListener;
class nsICycleCollectorLogSink;
class nsISupports;
template<class T> struct already_AddRefed;

#include "nsError.h"
#include "nsID.h"

#include "js/SliceBudget.h"

namespace mozilla {

class CycleCollectedJSRuntime;

// Called back from DeferredFinalize.  Should add 'thing' to the array of smart
// pointers in 'pointers', creating the array if 'pointers' is null, and return
// the array.
typedef void* (*DeferredFinalizeAppendFunction)(void* aPointers, void* aThing);

// Called to finalize a number of objects. Slice is the number of objects
// to finalize, or if it's UINT32_MAX, all objects should be finalized.
// Return value indicates whether it finalized all objects in the buffer.
typedef bool (*DeferredFinalizeFunction)(uint32_t aSlice, void* aData);

}

bool nsCycleCollector_init();

void nsCycleCollector_startup();

typedef void (*CC_BeforeUnlinkCallback)(void);
void nsCycleCollector_setBeforeUnlinkCallback(CC_BeforeUnlinkCallback aCB);

typedef void (*CC_ForgetSkippableCallback)(void);
void nsCycleCollector_setForgetSkippableCallback(CC_ForgetSkippableCallback aCB);

void nsCycleCollector_forgetSkippable(bool aRemoveChildlessNodes = false,
                                      bool aAsyncSnowWhiteFreeing = false);

void nsCycleCollector_prepareForGarbageCollection();

// If an incremental cycle collection is in progress, finish it.
void nsCycleCollector_finishAnyCurrentCollection();

void nsCycleCollector_dispatchDeferredDeletion(bool aContinuation = false);
bool nsCycleCollector_doDeferredDeletion();

already_AddRefed<nsICycleCollectorLogSink> nsCycleCollector_createLogSink();

void nsCycleCollector_collect(nsICycleCollectorListener* aManualListener);

void nsCycleCollector_collectSlice(js::SliceBudget& budget,
                                   bool aPreferShorterSlices = false);

uint32_t nsCycleCollector_suspectedCount();
void nsCycleCollector_shutdown();

// Helpers for interacting with JS
void nsCycleCollector_registerJSRuntime(mozilla::CycleCollectedJSRuntime* aRt);
void nsCycleCollector_forgetJSRuntime();

#define NS_CYCLE_COLLECTOR_LOGGER_CID \
{ 0x58be81b4, 0x39d2, 0x437c, \
{ 0x94, 0xea, 0xae, 0xde, 0x2c, 0x62, 0x08, 0xd3 } }

extern nsresult
nsCycleCollectorLoggerConstructor(nsISupports* aOuter,
                                  const nsIID& aIID,
                                  void** aInstancePtr);

namespace mozilla {
namespace cyclecollector {

#ifdef DEBUG
bool IsJSHolder(void* aHolder);
#endif

void DeferredFinalize(DeferredFinalizeAppendFunction aAppendFunc,
                      DeferredFinalizeFunction aFunc,
                      void* aThing);
void DeferredFinalize(nsISupports* aSupports);


} // namespace cyclecollector
} // namespace mozilla

#endif // nsCycleCollector_h__