xpcom/ds/nsObserverService.h
author Nicholas Nethercote <nnethercote@mozilla.com>
Thu, 28 Apr 2016 17:11:17 +1000
changeset 336701 1d99e6c5a2bf41b983658369b97c5d152649695b
parent 285589 4469946f2f7b753a9ee689b7575b50540ae1fddd
child 506430 c77a41fad0e6a6b22df9a077b536098adb42db86
permissions -rw-r--r--
Bug 1268772 (part 5) - Use MOZ_MUST_USE in other parts of xpcom/ds/. r=erahm. As well as adding MOZ_MUST_USE to a number of functions, this patch: - Changes the return type of nsObserverList::GetObserverList() from |nsresult| to |void|, because it always returned NS_OK and none of the callers checked the result. - Removes an unnecessary |new| check in nsSupportsArray::Enumerate().

/* -*- 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 nsObserverService_h___
#define nsObserverService_h___

#include "nsIObserverService.h"
#include "nsObserverList.h"
#include "nsIMemoryReporter.h"
#include "nsTHashtable.h"
#include "mozilla/Attributes.h"

// {D07F5195-E3D1-11d2-8ACD-00105A1B8860}
#define NS_OBSERVERSERVICE_CID \
    { 0xd07f5195, 0xe3d1, 0x11d2, { 0x8a, 0xcd, 0x0, 0x10, 0x5a, 0x1b, 0x88, 0x60 } }

class nsIMemoryReporter;

class nsObserverService final
  : public nsIObserverService
  , public nsIMemoryReporter
{
public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_OBSERVERSERVICE_CID)

  nsObserverService();

  NS_DECL_ISUPPORTS
  NS_DECL_NSIOBSERVERSERVICE
  NS_DECL_NSIMEMORYREPORTER

  void Shutdown();

  static MOZ_MUST_USE nsresult Create(nsISupports* aOuter, const nsIID& aIID,
                                      void** aInstancePtr);

  // Unmark any strongly held observers implemented in JS so the cycle
  // collector will not traverse them.
  NS_IMETHOD UnmarkGrayStrongObservers();

private:
  ~nsObserverService(void);
  void RegisterReporter();

  static const size_t kSuspectReferentCount = 100;
  bool mShuttingDown;
  nsTHashtable<nsObserverList> mObserverTopicTable;
};

NS_DEFINE_STATIC_IID_ACCESSOR(nsObserverService, NS_OBSERVERSERVICE_CID)

#endif /* nsObserverService_h___ */