dom/workers/WorkerHolderToken.cpp
author Jared Wein <jwein@mozilla.com>
Mon, 24 Dec 2018 16:19:20 +0000
changeset 511855 28805dd1b97ab5b421d9e886fd5d96460d5d26ab
parent 508163 6f3709b3878117466168c40affa7bca0b60cf75b
permissions -rw-r--r--
Bug 1507595 - Convert about:support to Fluent. r=Gijs,flod Initial patch by Collin Wing (masterkrombi@gmail.com). Differential Revision: https://phabricator.services.mozilla.com/D14905

/* -*- 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/. */

#include "WorkerHolderToken.h"

#include "WorkerPrivate.h"

namespace mozilla {
namespace dom {

// static
already_AddRefed<WorkerHolderToken> WorkerHolderToken::Create(
    WorkerPrivate* aWorkerPrivate, WorkerStatus aShutdownStatus,
    Behavior aBehavior) {
  MOZ_DIAGNOSTIC_ASSERT(aWorkerPrivate);
  aWorkerPrivate->AssertIsOnWorkerThread();

  RefPtr<WorkerHolderToken> workerHolder =
      new WorkerHolderToken(aShutdownStatus, aBehavior);

  if (NS_WARN_IF(!workerHolder->HoldWorker(aWorkerPrivate, aShutdownStatus))) {
    return nullptr;
  }

  return workerHolder.forget();
}

void WorkerHolderToken::AddListener(Listener* aListener) {
  NS_ASSERT_OWNINGTHREAD(WorkerHolderToken);
  MOZ_ASSERT(aListener);
  MOZ_ASSERT(!mListenerList.Contains(aListener));

  mListenerList.AppendElement(aListener);

  // Allow an actor to be added after we've entered the Notifying case.  We
  // can't stop the actor creation from racing with out destruction of the
  // other actors and we need to wait for this extra one to close as well.
  // Signal it should destroy itself right away.
  if (mShuttingDown) {
    aListener->WorkerShuttingDown();
  }
}

void WorkerHolderToken::RemoveListener(Listener* aListener) {
  NS_ASSERT_OWNINGTHREAD(WorkerHolderToken);
  MOZ_ASSERT(aListener);

  DebugOnly<bool> removed = mListenerList.RemoveElement(aListener);

  MOZ_ASSERT(removed);
  MOZ_ASSERT(!mListenerList.Contains(aListener));
}

bool WorkerHolderToken::IsShuttingDown() const { return mShuttingDown; }

WorkerPrivate* WorkerHolderToken::GetWorkerPrivate() const {
  NS_ASSERT_OWNINGTHREAD(WorkerHolderToken);
  return mWorkerPrivate;
}

WorkerHolderToken::WorkerHolderToken(WorkerStatus aShutdownStatus,
                                     Behavior aBehavior)
    : WorkerHolder("WorkerHolderToken", aBehavior),
      mShutdownStatus(aShutdownStatus),
      mShuttingDown(false) {}

WorkerHolderToken::~WorkerHolderToken() {
  NS_ASSERT_OWNINGTHREAD(WorkerHolderToken);
  MOZ_ASSERT(mListenerList.IsEmpty());
}

bool WorkerHolderToken::Notify(WorkerStatus aStatus) {
  NS_ASSERT_OWNINGTHREAD(WorkerHolderToken);

  // When the service worker thread is stopped we will get Canceling,
  // but nothing higher than that.  We must shut things down at Canceling.
  if (aStatus < mShutdownStatus || mShuttingDown) {
    return true;
  }

  // Start the asynchronous destruction of our actors.  These will call back
  // into RemoveActor() once the actor is destroyed.
  nsTObserverArray<Listener*>::ForwardIterator iter(mListenerList);
  while (iter.HasMore()) {
    iter.GetNext()->WorkerShuttingDown();
  }

  // Set this after calling WorkerShuttingDown() on listener list in case
  // one callback triggers another listener to be added.
  mShuttingDown = true;

  return true;
}

}  // namespace dom
}  // namespace mozilla