image/ShutdownTracker.cpp
author Noemi Erli <nerli@mozilla.com>
Thu, 20 Jun 2019 22:13:33 +0300
changeset 479716 7034f38fc20714e2467db5288b4896db811afbef
parent 461891 240e874ed11862376247ea177a88ddf00924e0da
permissions -rw-r--r--
Backed out 3 changesets (bug 1557265) for causing Linux bustages CLOSED TREE Backed out changeset 5e797f74091a (bug 1557265) Backed out changeset f10c947516e0 (bug 1557265) Backed out changeset f7e5ef31a50b (bug 1557265)

/* -*- 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/. */

#include "ShutdownTracker.h"

#include "mozilla/Services.h"
#include "nsIObserver.h"
#include "nsIObserverService.h"

namespace mozilla {
namespace image {

class ShutdownTrackerImpl;

///////////////////////////////////////////////////////////////////////////////
// Static Data
///////////////////////////////////////////////////////////////////////////////

// Whether we've observed shutdown starting yet.
static bool sShutdownHasStarted = false;

///////////////////////////////////////////////////////////////////////////////
// Implementation
///////////////////////////////////////////////////////////////////////////////

struct ShutdownObserver : public nsIObserver {
  NS_DECL_ISUPPORTS

  NS_IMETHOD Observe(nsISupports*, const char* aTopic,
                     const char16_t*) override {
    if (strcmp(aTopic, "xpcom-will-shutdown") != 0) {
      return NS_OK;
    }

    nsCOMPtr<nsIObserverService> os = services::GetObserverService();
    if (os) {
      os->RemoveObserver(this, "xpcom-will-shutdown");
    }

    sShutdownHasStarted = true;
    return NS_OK;
  }

 private:
  virtual ~ShutdownObserver() {}
};

NS_IMPL_ISUPPORTS(ShutdownObserver, nsIObserver)

///////////////////////////////////////////////////////////////////////////////
// Public API
///////////////////////////////////////////////////////////////////////////////

/* static */
void ShutdownTracker::Initialize() {
  nsCOMPtr<nsIObserverService> os = services::GetObserverService();
  if (os) {
    os->AddObserver(new ShutdownObserver, "xpcom-will-shutdown", false);
  }
}

/* static */
bool ShutdownTracker::ShutdownHasStarted() { return sShutdownHasStarted; }

}  // namespace image
}  // namespace mozilla