C++ js::Handle类代码示例

JSBool JavaObject::getPropertyWrapper(JSContext* ctx, JS::Handle<JSObject*> obj,
    JS::Handle<jsid> id, JS::MutableHandle<JS::Value> vp) {
  jsval rval;
  JSBool result = JavaObject::getProperty(ctx, obj.get(), id.get(), &rval);
  vp.set(rval);
  return result;
}

// static
nsresult
IDBKeyRange::FromJSVal(JSContext* aCx,
                       JS::Handle<JS::Value> aVal,
                       IDBKeyRange** aKeyRange)
{
  nsRefPtr<IDBKeyRange> keyRange;

  if (aVal.isNullOrUndefined()) {
    // undefined and null returns no IDBKeyRange.
    keyRange.forget(aKeyRange);
    return NS_OK;
  }

  JS::Rooted<JSObject*> obj(aCx, aVal.isObject() ? &aVal.toObject() : nullptr);
  if (aVal.isPrimitive() || JS_IsArrayObject(aCx, obj) ||
      JS_ObjectIsDate(aCx, obj)) {
    // A valid key returns an 'only' IDBKeyRange.
    keyRange = new IDBKeyRange(nullptr, false, false, true);

    nsresult rv = GetKeyFromJSVal(aCx, aVal, keyRange->Lower());
    if (NS_FAILED(rv)) {
      return rv;
    }
  }
  else {
    MOZ_ASSERT(aVal.isObject());
    // An object is not permitted unless it's another IDBKeyRange.
    if (NS_FAILED(UNWRAP_OBJECT(IDBKeyRange, obj, keyRange))) {
      return NS_ERROR_DOM_INDEXEDDB_DATA_ERR;
    }
  }

  keyRange.forget(aKeyRange);
  return NS_OK;
}

NS_IMETHODIMP
GonkGPSGeolocationProvider::Handle(const nsAString& aName,
                                   JS::Handle<JS::Value> aResult)
{
#ifdef MOZ_B2G_RIL
  if (aName.EqualsLiteral("ril.supl.apn")) {
    // When we get the APN, we attempt to call data_call_open of AGPS.
    if (aResult.isString()) {
      JSContext *cx = nsContentUtils::GetCurrentJSContext();
      NS_ENSURE_TRUE(cx, NS_OK);

      // NB: No need to enter a compartment to read the contents of a string.
      nsAutoJSString apn;
      if (!apn.init(cx, aResult.toString())) {
        return NS_ERROR_FAILURE;
      }
      if (!apn.IsEmpty()) {
        SetAGpsDataConn(apn);
      }
    }
  } else
#endif // MOZ_B2G_RIL
  if (aName.EqualsLiteral(SETTING_DEBUG_ENABLED)) {
    gGPSDebugging = aResult.isBoolean() ? aResult.toBoolean() : false;
    return NS_OK;
  }
  return NS_OK;
}

// PromiseNativeHandler
void
PresentationResponderInfo::ResolvedCallback(JSContext* aCx,
                                            JS::Handle<JS::Value> aValue)
{
  MOZ_ASSERT(NS_IsMainThread());

  if (NS_WARN_IF(!aValue.isObject())) {
    ReplyError(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  JS::Rooted<JSObject*> obj(aCx, &aValue.toObject());
  if (NS_WARN_IF(!obj)) {
    ReplyError(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  // Start to listen to document state change event |STATE_TRANSFERRING|.
  HTMLIFrameElement* frame = nullptr;
  nsresult rv = UNWRAP_OBJECT(HTMLIFrameElement, obj, frame);
  if (NS_WARN_IF(!frame)) {
    ReplyError(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  nsCOMPtr<nsIFrameLoaderOwner> owner = do_QueryInterface((nsIFrameLoaderOwner*) frame);
  if (NS_WARN_IF(!owner)) {
    ReplyError(NS_ERROR_NOT_AVAILABLE);
    return;
  }

  nsCOMPtr<nsIFrameLoader> frameLoader;
  rv = owner->GetFrameLoader(getter_AddRefs(frameLoader));
  if (NS_WARN_IF(NS_FAILED(rv))) {
    ReplyError(rv);
    return;
  }

  nsRefPtr<TabParent> tabParent = TabParent::GetFrom(frameLoader);
  if (tabParent) {
    // OOP frame
    nsCOMPtr<nsIContentParent> cp = tabParent->Manager();
    NS_WARN_IF(!static_cast<ContentParent*>(cp.get())->SendNotifyPresentationReceiverLaunched(tabParent, mSessionId));
  } else {
    // In-process frame
    nsCOMPtr<nsIDocShell> docShell;
    rv = frameLoader->GetDocShell(getter_AddRefs(docShell));
    if (NS_WARN_IF(NS_FAILED(rv))) {
      ReplyError(rv);
      return;
    }

    mLoadingCallback = new PresentationResponderLoadingCallback(mSessionId);
    rv = mLoadingCallback->Init(docShell);
    if (NS_WARN_IF(NS_FAILED(rv))) {
      ReplyError(rv);
      return;
    }
  }
}

NS_IMETHODIMP
ArrayBufferInputStream::SetData(JS::Handle<JS::Value> aBuffer,
                                uint32_t aByteOffset,
                                uint32_t aLength,
                                JSContext* aCx)
{
  if (!aBuffer.isObject()) {
    return NS_ERROR_FAILURE;
  }
  JS::RootedObject arrayBuffer(aCx, &aBuffer.toObject());
  if (!JS_IsArrayBufferObject(arrayBuffer)) {
    return NS_ERROR_FAILURE;
  }

  mArrayBuffer.construct(aCx, aBuffer);

  uint32_t buflen = JS_GetArrayBufferByteLength(arrayBuffer);
  mOffset = std::min(buflen, aByteOffset);
  mBufferLength = std::min(buflen - mOffset, aLength);
  mBuffer = JS_GetStableArrayBufferData(aCx, arrayBuffer);
  if (!mBuffer) {
      return NS_ERROR_FAILURE;
  }
  return NS_OK;
}

bool
FieldSetterImpl(JSContext *cx, JS::CallArgs args)
{
  JS::Handle<JS::Value> thisv = args.thisv();
  MOZ_ASSERT(ValueHasISupportsPrivate(thisv));

  JS::Rooted<JSObject*> thisObj(cx, &thisv.toObject());

  // We should be in the compartment of |this|. If we got here via nativeCall,
  // |this| is not same-compartment with |callee|, and it's possible via
  // asymmetric security semantics that |args.calleev()| is actually a security
  // wrapper. In this case, we know we want to do an unsafe unwrap, and
  // InstallXBLField knows how to handle cross-compartment pointers.
  bool installed = false;
  JS::Rooted<JSObject*> callee(cx, js::UncheckedUnwrap(&args.calleev().toObject()));
  JS::Rooted<jsid> id(cx);
  if (!InstallXBLField(cx, callee, thisObj, &id, &installed)) {
    return false;
  }

  if (installed) {
    if (!::JS_SetPropertyById(cx, thisObj, id, args.get(0))) {
      return false;
    }
  }
  args.rval().setUndefined();
  return true;
}

NS_IMETHODIMP
TCPSocketParent::InitJS(JS::Handle<JS::Value> aIntermediary, JSContext* aCx)
{
  MOZ_ASSERT(aIntermediary.isObject());
  mIntermediaryObj = &aIntermediary.toObject();
  return NS_OK;
}

  NS_IMETHOD Handle(const nsAString& aName, JS::Handle<JS::Value> aResult)
  {
    RefPtr<AudioManager> audioManager = AudioManager::GetInstance();
    MOZ_ASSERT(audioManager);
    for (uint32_t idx = 0; idx < MOZ_ARRAY_LENGTH(gVolumeData); ++idx) {
      NS_ConvertASCIItoUTF16 volumeType(gVolumeData[idx].mChannelName);
      if (StringBeginsWith(aName, volumeType)) {
        uint32_t device = GetDeviceFromSettingName(aName);
        MOZ_ASSERT(device != AUDIO_DEVICE_NONE);
        if (aResult.isInt32()) {
          int32_t stream = gVolumeData[idx].mStreamType;
          uint32_t volIndex = aResult.toInt32();
          nsresult rv = audioManager->ValidateVolumeIndex(stream, volIndex);
          if (NS_WARN_IF(NS_FAILED(rv))) {
            mPromiseHolder.Reject("Error : invalid volume index.", __func__);
            return rv;
          }
          audioManager->SetStreamVolumeForDevice(stream, volIndex, device);
        }

        if (++mInitCounter == MOZ_ARRAY_LENGTH(kAudioDeviceInfos) * MOZ_ARRAY_LENGTH(gVolumeData)) {
          mPromiseHolder.Resolve(true, __func__);
        }
        return NS_OK;
      }
    }
    mPromiseHolder.Reject("Error : unexpected audio init event.", __func__);
    return NS_OK;
  }

NS_IMETHODIMP
nsBinaryInputStream::ReadArrayBuffer(uint32_t aLength,
                                     JS::Handle<JS::Value> aBuffer,
                                     JSContext* aCx, uint32_t* aReadLength)
{
  if (!aBuffer.isObject()) {
    return NS_ERROR_FAILURE;
  }
  JS::RootedObject buffer(aCx, &aBuffer.toObject());
  if (!JS_IsArrayBufferObject(buffer)) {
    return NS_ERROR_FAILURE;
  }

  uint32_t bufferLength = JS_GetArrayBufferByteLength(buffer);
  if (bufferLength < aLength) {
    return NS_ERROR_FAILURE;
  }

  uint32_t bufSize = std::min<uint32_t>(aLength, 4096);
  UniquePtr<char[]> buf = MakeUnique<char[]>(bufSize);

  uint32_t pos = 0;
  *aReadLength = 0;
  do {
    // Read data into temporary buffer.
    uint32_t bytesRead;
    uint32_t amount = std::min(aLength - pos, bufSize);
    nsresult rv = Read(buf.get(), amount, &bytesRead);
    if (NS_WARN_IF(NS_FAILED(rv))) {
      return rv;
    }
    MOZ_ASSERT(bytesRead <= amount);

    if (bytesRead == 0) {
      break;
    }

    // Copy data into actual buffer.

    JS::AutoCheckCannotGC nogc;
    bool isShared;
    if (bufferLength != JS_GetArrayBufferByteLength(buffer)) {
      return NS_ERROR_FAILURE;
    }

    char* data = reinterpret_cast<char*>(JS_GetArrayBufferData(buffer, &isShared, nogc));
    MOZ_ASSERT(!isShared);      // Implied by JS_GetArrayBufferData()
    if (!data) {
      return NS_ERROR_FAILURE;
    }

    *aReadLength += bytesRead;
    PodCopy(data + pos, buf.get(), bytesRead);

    pos += bytesRead;
  } while (pos < aLength);

  return NS_OK;
}

NS_IMETHODIMP
nsSpeechTask::SendAudio(JS::Handle<JS::Value> aData, JS::Handle<JS::Value> aLandmarks,
                        JSContext* aCx)
{
  MOZ_ASSERT(XRE_IsParentProcess());

  if(NS_WARN_IF(!(mStream))) {
    return NS_ERROR_NOT_AVAILABLE;
  }
  if(NS_WARN_IF(mStream->IsDestroyed())) {
    return NS_ERROR_NOT_AVAILABLE;
  }
  if(NS_WARN_IF(!(mChannels))) {
    return NS_ERROR_FAILURE;
  }
  if(NS_WARN_IF(!(aData.isObject()))) {
    return NS_ERROR_INVALID_ARG;
  }

  if (mIndirectAudio) {
    NS_WARNING("Can't call SendAudio from an indirect audio speech service.");
    return NS_ERROR_FAILURE;
  }

  JS::Rooted<JSObject*> darray(aCx, &aData.toObject());
  JSAutoCompartment ac(aCx, darray);

  JS::Rooted<JSObject*> tsrc(aCx, nullptr);

  // Allow either Int16Array or plain JS Array
  if (JS_IsInt16Array(darray)) {
    tsrc = darray;
  } else {
    bool isArray;
    if (!JS_IsArrayObject(aCx, darray, &isArray)) {
      return NS_ERROR_UNEXPECTED;
    }
    if (isArray) {
      tsrc = JS_NewInt16ArrayFromArray(aCx, darray);
    }
  }

  if (!tsrc) {
    return NS_ERROR_DOM_TYPE_MISMATCH_ERR;
  }

  uint32_t dataLen = JS_GetTypedArrayLength(tsrc);
  RefPtr<mozilla::SharedBuffer> samples;
  {
    JS::AutoCheckCannotGC nogc;
    samples = makeSamples(JS_GetInt16ArrayData(tsrc, nogc), dataLen);
  }
  SendAudioImpl(samples, dataLen);

  return NS_OK;
}

static already_AddRefed<EventListener>
ToEventListener(JSContext* aCx, JS::Handle<JS::Value> aValue)
{
  if (NS_WARN_IF(!aValue.isObject())) {
    return nullptr;
  }

  JS::Rooted<JSObject*> obj(aCx, &aValue.toObject());
  RefPtr<EventListener> listener =
    new EventListener(aCx, obj, GetIncumbentGlobal());
  return listener.forget();
}

NS_IMETHODIMP
GonkGPSGeolocationProvider::Handle(const nsAString& aName,
                                   JS::Handle<JS::Value> aResult)
{
#ifdef MOZ_B2G_RIL
  if (aName.EqualsLiteral("ril.supl.apn")) {
    // When we get the APN, we attempt to call data_call_open of AGPS.
    if (aResult.isString()) {
      JSContext *cx = nsContentUtils::GetCurrentJSContext();
      NS_ENSURE_TRUE(cx, NS_OK);

      // NB: No need to enter a compartment to read the contents of a string.
      nsAutoJSString apn;
      if (!apn.init(cx, aResult.toString())) {
        return NS_ERROR_FAILURE;
      }
      if (!apn.IsEmpty()) {
        SetAGpsDataConn(apn);
      }
    }
  } else if (aName.EqualsASCII(kSettingRilDefaultServiceId)) {
    uint32_t id = 0;
    JSContext *cx = nsContentUtils::GetCurrentJSContext();
    NS_ENSURE_TRUE(cx, NS_OK);
    if (!JS::ToUint32(cx, aResult, &id)) {
      return NS_ERROR_FAILURE;
    }

    if (!IsValidRilServiceId(id)) {
      return NS_ERROR_UNEXPECTED;
    }

    mRilDataServiceId = id;
    UpdateRadioInterface();

    MOZ_ASSERT(!mObservingNetworkConnStateChange);

    // Now we know which service ID to deal with, observe necessary topic then
    nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
    NS_ENSURE_TRUE(obs, NS_OK);

    if (NS_FAILED(obs->AddObserver(this, kNetworkConnStateChangedTopic, false))) {
      NS_WARNING("Failed to add network state changed observer!");
    } else {
      mObservingNetworkConnStateChange = true;
    }
  }
#endif // MOZ_B2G_RIL
  return NS_OK;
}

NS_IMETHODIMP
SmsFilter::SetRead(JSContext* aCx, JS::Handle<JS::Value> aRead)
{
  if (aRead.isNull()) {
    mData.read() = eReadState_Unknown;
    return NS_OK;
  }

  if (!aRead.isBoolean()) {
    return NS_ERROR_INVALID_ARG;
  }

  mData.read() = aRead.toBoolean() ? eReadState_Read : eReadState_Unread;
  return NS_OK;
}

NS_IMETHODIMP
WebVTTListener::OnRegion(JS::Handle<JS::Value> aRegion, JSContext* aCx)
{
  if (!aRegion.isObject()) {
    return NS_ERROR_FAILURE;
  }

  TextTrackRegion* region;
  nsresult rv = UNWRAP_OBJECT(VTTRegion, &aRegion.toObject(), region);
  NS_ENSURE_SUCCESS(rv, rv);

  mElement->mTrack->AddRegion(*region);

  return NS_OK;
}

js_DefineOwnProperty(JSContext *cx, JSObject *objArg, jsid idArg,
                     JS::Handle<js::PropertyDescriptor> descriptor, bool *bp)
{
    RootedObject obj(cx, objArg);
    RootedId id(cx, idArg);
    js::AssertHeapIsIdle(cx);
    CHECK_REQUEST(cx);
    assertSameCompartment(cx, obj, id, descriptor.value());
    if (descriptor.hasGetterObject())
        assertSameCompartment(cx, descriptor.getterObject());
    if (descriptor.hasSetterObject())
        assertSameCompartment(cx, descriptor.setterObject());

    return DefineOwnProperty(cx, HandleObject(obj), id, descriptor, bp);
}