The Tor Browser: dom/speakermanager/SpeakerManager.cpp@97036ab72558 (annotated)

dom/speakermanager/SpeakerManager.cpp@97036ab72558 (annotated)

dom/speakermanager/SpeakerManager.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* 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 "SpeakerManager.h"
 #include "nsIDOMClassInfo.h"
 #include "nsIDOMEvent.h"
 #include "nsIDOMEventListener.h"
 #include "SpeakerManagerService.h"
 #include "nsIPermissionManager.h"
 #include "nsIInterfaceRequestorUtils.h"
 #include "nsIDocShell.h"
 #include "AudioChannelService.h"
 namespace mozilla {
 namespace dom {
 NS_IMPL_QUERY_INTERFACE_INHERITED(SpeakerManager, DOMEventTargetHelper,
                                   nsIDOMEventListener)
 NS_IMPL_ADDREF_INHERITED(SpeakerManager, DOMEventTargetHelper)
 NS_IMPL_RELEASE_INHERITED(SpeakerManager, DOMEventTargetHelper)
 SpeakerManager::SpeakerManager()
   : mForcespeaker(false)
   , mVisible(false)
 {
   SetIsDOMBinding();
   SpeakerManagerService *service =
     SpeakerManagerService::GetSpeakerManagerService();
   if (service) {
     service->RegisterSpeakerManager(this);
   }
 }
 SpeakerManager::~SpeakerManager()
 {
   SpeakerManagerService *service = SpeakerManagerService::GetSpeakerManagerService();
   if (service) {
     service->UnRegisterSpeakerManager(this);
   }
   nsCOMPtr<EventTarget> target = do_QueryInterface(GetOwner());
   NS_ENSURE_TRUE_VOID(target);
   target->RemoveSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
                                     this,
                                     /* useCapture = */ true);
 }
 bool
 SpeakerManager::Speakerforced()
 {
   // If a background app calls forcespeaker=true that doesn't change anything.
   // 'speakerforced' remains false everywhere.
   if (mForcespeaker && !mVisible) {
     return false;
   }
   SpeakerManagerService *service = SpeakerManagerService::GetSpeakerManagerService();
   if (service) {
     return service->GetSpeakerStatus();
   }
   return false;
 }
 bool
 SpeakerManager::Forcespeaker()
 {
   return mForcespeaker;
 }
 void
 SpeakerManager::SetForcespeaker(bool aEnable)
 {
   SpeakerManagerService *service = SpeakerManagerService::GetSpeakerManagerService();
   if (service) {
     service->ForceSpeaker(aEnable, mVisible);
   }
   mForcespeaker = aEnable;
 }
 void
 SpeakerManager::DispatchSimpleEvent(const nsAString& aStr)
 {
   NS_ABORT_IF_FALSE(NS_IsMainThread(), "Not running on main thread");
   nsresult rv = CheckInnerWindowCorrectness();
   if (NS_FAILED(rv)) {
     return;
   }
   nsCOMPtr<nsIDOMEvent> event;
   rv = NS_NewDOMEvent(getter_AddRefs(event), this, nullptr, nullptr);
   if (NS_FAILED(rv)) {
     NS_WARNING("Failed to create the error event!!!");
     return;
   }
   rv = event->InitEvent(aStr, false, false);
   if (NS_FAILED(rv)) {
     NS_WARNING("Failed to init the error event!!!");
     return;
   }
   event->SetTrusted(true);
   rv = DispatchDOMEvent(nullptr, event, nullptr, nullptr);
   if (NS_FAILED(rv)) {
     NS_ERROR("Failed to dispatch the event!!!");
     return;
   }
 }
 void
 SpeakerManager::Init(nsPIDOMWindow* aWindow)
 {
   BindToOwner(aWindow);
   nsCOMPtr<nsIDocShell> docshell = do_GetInterface(GetOwner());
   NS_ENSURE_TRUE_VOID(docshell);
   docshell->GetIsActive(&mVisible);
   nsCOMPtr<nsIDOMEventTarget> target = do_QueryInterface(GetOwner());
   NS_ENSURE_TRUE_VOID(target);
   target->AddSystemEventListener(NS_LITERAL_STRING("visibilitychange"),
                                  this,
                                  /* useCapture = */ true,
                                  /* wantsUntrusted = */ false);
 }
 nsPIDOMWindow*
 SpeakerManager::GetParentObject() const
 {
   return GetOwner();
 }
 /* static */ already_AddRefed<SpeakerManager>
 SpeakerManager::Constructor(const GlobalObject& aGlobal, ErrorResult& aRv)
 {
   nsCOMPtr<nsIScriptGlobalObject> sgo = do_QueryInterface(aGlobal.GetAsSupports());
   if (!sgo) {
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
   nsCOMPtr<nsPIDOMWindow> ownerWindow = do_QueryInterface(aGlobal.GetAsSupports());
   if (!ownerWindow) {
     aRv.Throw(NS_ERROR_FAILURE);
     return nullptr;
   }
   nsCOMPtr<nsIPermissionManager> permMgr =
     do_GetService(NS_PERMISSIONMANAGER_CONTRACTID);
   NS_ENSURE_TRUE(permMgr, nullptr);
   uint32_t permission = nsIPermissionManager::DENY_ACTION;
   nsresult rv =
     permMgr->TestPermissionFromWindow(ownerWindow, "speaker-control",
                                       &permission);
   NS_ENSURE_SUCCESS(rv, nullptr);
   if (permission != nsIPermissionManager::ALLOW_ACTION) {
     aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
     return nullptr;
   }
   nsRefPtr<SpeakerManager> object = new SpeakerManager();
   object->Init(ownerWindow);
   return object.forget();
 }
 JSObject*
 SpeakerManager::WrapObject(JSContext* aCx)
 {
   return MozSpeakerManagerBinding::Wrap(aCx, this);
 }
 NS_IMETHODIMP
 SpeakerManager::HandleEvent(nsIDOMEvent* aEvent)
 {
   nsAutoString type;
   aEvent->GetType(type);
   if (!type.EqualsLiteral("visibilitychange")) {
     return NS_ERROR_FAILURE;
   }
   nsCOMPtr<nsIDocShell> docshell = do_GetInterface(GetOwner());
   NS_ENSURE_TRUE(docshell, NS_ERROR_FAILURE);
   docshell->GetIsActive(&mVisible);
   // If an app that has called forcespeaker=true is switched
   // from the background to the foreground 'speakerforced'
   // switches to true in all apps. I.e. the app doesn't have to
   // call forcespeaker=true again when it comes into foreground.
   SpeakerManagerService *service =
     SpeakerManagerService::GetSpeakerManagerService();
   if (service && mVisible && mForcespeaker) {
     service->ForceSpeaker(mForcespeaker, mVisible);
   }
   // If an application that has called forcespeaker=true, but no audio is
   // currently playing in the app itself, if application switch to
   // the background, we switch 'speakerforced' to false.
   if (!mVisible && mForcespeaker) {
     AudioChannelService* audioChannelService =
       AudioChannelService::GetAudioChannelService();
     if (audioChannelService && !audioChannelService->AnyAudioChannelIsActive()) {
       service->ForceSpeaker(false, mVisible);
     }
   }
   return NS_OK;
 }
 void
 SpeakerManager::SetAudioChannelActive(bool isActive)
 {
   if (!isActive && !mVisible) {
     SpeakerManagerService *service =
       SpeakerManagerService::GetSpeakerManagerService();
     if (service) {
       service->ForceSpeaker(false, mVisible);
     }
   }
 }
 } // namespace dom
 } // namespace mozilla

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dom/speakermanager/SpeakerManager.cpp@97036ab72558 (annotated)

dom/speakermanager/SpeakerManager.cpp