C++ MutableHandle::set方法代码示例

void
WorkerDebuggerGlobalScope::CreateSandbox(JSContext* aCx, const nsAString& aName,
                                         JS::Handle<JSObject*> aPrototype,
                                         JS::MutableHandle<JSObject*> aResult,
                                         ErrorResult& aRv)
{
  mWorkerPrivate->AssertIsOnWorkerThread();

  aResult.set(nullptr);

  JS::Rooted<JS::Value> protoVal(aCx);
  protoVal.setObjectOrNull(aPrototype);
  JS::Rooted<JSObject*> sandbox(aCx,
    SimpleGlobalObject::Create(SimpleGlobalObject::GlobalType::WorkerDebuggerSandbox,
                               protoVal));

  if (!sandbox) {
    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return;
  }

  if (!JS_WrapObject(aCx, &sandbox)) {
    aRv.NoteJSContextException(aCx);
    return;
  }

  aResult.set(sandbox);
}

void
IDBIndex::GetKeyPath(JSContext* aCx,
                     JS::MutableHandle<JS::Value> aResult,
                     ErrorResult& aRv)
{
  AssertIsOnOwningThread();

  if (!mCachedKeyPath.isUndefined()) {
    MOZ_ASSERT(mRooted);
    JS::ExposeValueToActiveJS(mCachedKeyPath);
    aResult.set(mCachedKeyPath);
    return;
  }

  MOZ_ASSERT(!mRooted);

  aRv = GetKeyPath().ToJSVal(aCx, mCachedKeyPath);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }

  if (mCachedKeyPath.isGCThing()) {
    mozilla::HoldJSObjects(this);
    mRooted = true;
  }

  JS::ExposeValueToActiveJS(mCachedKeyPath);
  aResult.set(mCachedKeyPath);
}

/* jsval testJsval (in jsval a, in jsval b); */
NS_IMETHODIMP nsXPCTestParams::TestJsval(JS::Handle<JS::Value> a,
                                         JS::MutableHandle<JS::Value> b,
                                         JS::MutableHandle<JS::Value> _retval)
{
    _retval.set(b);
    b.set(a);
    return NS_OK;
}

void
WebGLContext::GetExtension(JSContext* cx,
                           const nsAString& wideName,
                           JS::MutableHandle<JSObject*> retval,
                           dom::CallerType callerType,
                           ErrorResult& rv)
{
    retval.set(nullptr);

    if (IsContextLost())
        return;

    NS_LossyConvertUTF16toASCII name(wideName);

    WebGLExtensionID ext = WebGLExtensionID::Unknown;

    // step 1: figure what extension is wanted
    for (size_t i = 0; i < size_t(WebGLExtensionID::Max); i++) {
        WebGLExtensionID extension = WebGLExtensionID(i);

        if (CompareWebGLExtensionName(name, GetExtensionString(extension))) {
            ext = extension;
            break;
        }
    }

    if (ext == WebGLExtensionID::Unknown)
        return;

    // step 2: check if the extension is supported
    if (!IsExtensionSupported(callerType, ext))
        return;

    // step 3: if the extension hadn't been previously been created, create it now, thus enabling it
    WebGLExtensionBase* extObj = EnableSupportedExtension(callerType, ext);
    if (!extObj)
        return;

    // Step 4: Enable any implied extensions.
    switch (ext) {
    case WebGLExtensionID::OES_texture_float:
        EnableSupportedExtension(callerType,
                                 WebGLExtensionID::WEBGL_color_buffer_float);
        break;

    case WebGLExtensionID::OES_texture_half_float:
        EnableSupportedExtension(callerType,
                                 WebGLExtensionID::EXT_color_buffer_half_float);
        break;

    default:
        break;
    }

    retval.set(WebGLObjectAsJSObject(cx, extObj, rv));
}

void
WebGLExtensionMOZDebug::GetParameter(JSContext* cx, GLenum pname,
                                     JS::MutableHandle<JS::Value> retval,
                                     ErrorResult& er) const
{
    const auto& gl = mContext->gl;
    gl->MakeCurrent();

    switch (pname) {
    case LOCAL_GL_EXTENSIONS:
        {
            nsString ret;
            if (!gl->IsCoreProfile()) {
                const auto rawExts = (const char*)gl->fGetString(LOCAL_GL_EXTENSIONS);
                ret = NS_ConvertUTF8toUTF16(rawExts);
            } else {
                const auto& numExts = gl->GetIntAs<GLuint>(LOCAL_GL_NUM_EXTENSIONS);
                for (GLuint i = 0; i < numExts; i++) {
                    const auto rawExt = (const char*)gl->fGetStringi(LOCAL_GL_EXTENSIONS,
                                                                     i);
                    if (i > 0) {
                        ret.AppendLiteral(" ");
                    }
                    ret.Append(NS_ConvertUTF8toUTF16(rawExt));
                }
            }
            retval.set(StringValue(cx, ret, er));
            return;
        }

    case LOCAL_GL_RENDERER:
    case LOCAL_GL_VENDOR:
    case LOCAL_GL_VERSION:
        {
            const auto raw = (const char*)gl->fGetString(pname);
            retval.set(StringValue(cx, NS_ConvertUTF8toUTF16(raw), er));
            return;
        }

    case 0x10000: // "WSI_INFO"
        {
            nsCString info;
            gl->GetWSIInfo(&info);
            retval.set(StringValue(cx, NS_ConvertUTF8toUTF16(info), er));
            return;
        }

    default:
        mContext->ErrorInvalidEnumArg("MOZ_debug.getParameter", "pname", pname);
        retval.set(JS::NullValue());
        return;
    }
}

void
WaveShaperNode::GetCurve(JSContext* aCx,
                         JS::MutableHandle<JSObject*> aRetval)
{
  // Let's return a null value if the list is empty.
  if (mCurve.IsEmpty()) {
    aRetval.set(nullptr);
    return;
  }

  MOZ_ASSERT(mCurve.Length() >= 2);
  aRetval.set(Float32Array::Create(aCx, this, mCurve.Length(),
                                   mCurve.Elements()));
}

nsresult
DOMCameraCapabilities::ParameterListToNewArray(JSContext* aCx,
                                               JS::MutableHandle<JSObject*> aArray,
                                               uint32_t aKey,
                                               ParseItemAndAddFunc aParseItemAndAdd)
{
  NS_ENSURE_TRUE(mCamera, NS_ERROR_NOT_AVAILABLE);

  const char* value = mCamera->GetParameterConstChar(aKey);
  if (!value) {
    // in case we get nonsense data back
    aArray.set(nullptr);
    return NS_OK;
  }

  aArray.set(JS_NewArrayObject(aCx, 0, nullptr));
  if (!aArray) {
    return NS_ERROR_OUT_OF_MEMORY;
  }

  const char* p = value;
  uint32_t index = 0;
  nsresult rv;
  char* q;

  while (p) {
    /**
     * In C's string.h, strchr() is declared as returning 'char*'; in C++'s
     * cstring, it is declared as returning 'const char*', _except_ in MSVC,
     * where the C version is declared to return const like the C++ version.
     *
     * Unfortunately, for both cases, strtod() and strtol() take a 'char**' as
     * the end-of-conversion pointer, so we need to cast away strchr()'s
     * const-ness here to make the MSVC build everything happy.
     */
    q = const_cast<char*>(strchr(p, ','));
    if (q != p) { // skip consecutive delimiters, just in case
      rv = aParseItemAndAdd(aCx, aArray, index, p, &q);
      NS_ENSURE_SUCCESS(rv, rv);
      ++index;
    }
    p = q;
    if (p) {
      ++p;
    }
  }

  return JS_FreezeObject(aCx, aArray) ? NS_OK : NS_ERROR_FAILURE;
}

void
IDBCursor::GetPrimaryKey(JSContext* aCx, JS::MutableHandle<JS::Value> aResult,
                         ErrorResult& aRv)
{
  AssertIsOnOwningThread();

  if (!mHaveValue) {
    aResult.setUndefined();
    return;
  }

  if (!mHaveCachedPrimaryKey) {
    if (!mRooted) {
      mozilla::HoldJSObjects(this);
      mRooted = true;
    }

    const Key& key =
      (mType == Type_ObjectStore || mType == Type_ObjectStoreKey) ?
      mKey :
      mPrimaryKey;

    MOZ_ASSERT(!key.IsUnset());

    aRv = key.ToJSVal(aCx, mCachedPrimaryKey);
    if (NS_WARN_IF(aRv.Failed())) {
      return;
    }

    mHaveCachedPrimaryKey = true;
  }

  JS::ExposeValueToActiveJS(mCachedPrimaryKey);
  aResult.set(mCachedPrimaryKey);
}

bool BaseDOMProxyHandler::getPrototypeIfOrdinary(
    JSContext* cx, JS::Handle<JSObject*> proxy, bool* isOrdinary,
    JS::MutableHandle<JSObject*> proto) const {
  *isOrdinary = true;
  proto.set(GetStaticPrototype(proxy));
  return true;
}

void
FileReader::GetResult(JSContext* aCx,
                      JS::MutableHandle<JS::Value> aResult,
                      ErrorResult& aRv)
{
  JS::Rooted<JS::Value> result(aCx);

  if (mDataFormat == FILE_AS_ARRAYBUFFER) {
    if (mReadyState == DONE && mResultArrayBuffer) {
      result.setObject(*mResultArrayBuffer);
    } else {
      result.setNull();
    }

    if (!JS_WrapValue(aCx, &result)) {
      aRv.Throw(NS_ERROR_FAILURE);
      return;
    }

    aResult.set(result);
    return;
  }

  nsString tmpResult = mResult;
  if (!xpc::StringToJsval(aCx, tmpResult, aResult)) {
    aRv.Throw(NS_ERROR_FAILURE);
    return;
  }
}

void FetchStreamReader::StartConsuming(JSContext* aCx, JS::HandleObject aStream,
                                       JS::MutableHandle<JSObject*> aReader,
                                       ErrorResult& aRv) {
  MOZ_DIAGNOSTIC_ASSERT(!mReader);
  MOZ_DIAGNOSTIC_ASSERT(aStream);

  aRv.MightThrowJSException();

  // Here, by spec, we can pick any global we want. Just to avoid extra
  // cross-compartment steps, we want to create the reader in the same
  // compartment of the owning Fetch Body object.
  // The same global will be used to retrieve data from this reader.
  JSAutoRealm ar(aCx, mGlobal->GetGlobalJSObject());

  JS::Rooted<JSObject*> reader(
      aCx, JS::ReadableStreamGetReader(aCx, aStream,
                                       JS::ReadableStreamReaderMode::Default));
  if (!reader) {
    aRv.StealExceptionFromJSContext(aCx);
    CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  mReader = reader;
  aReader.set(reader);

  aRv = mPipeOut->AsyncWait(this, 0, 0, mOwningEventTarget);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }
}

void
TextEncoder::Encode(JSContext* aCx,
                    JS::Handle<JSObject*> aObj,
                    const nsAString& aString,
                    JS::MutableHandle<JSObject*> aRetval,
                    ErrorResult& aRv)
{
  nsAutoCString utf8;
  nsresult rv;
  const Encoding* ignored;
  Tie(rv, ignored) = UTF_8_ENCODING->Encode(aString, utf8);
  if (NS_FAILED(rv)) {
    aRv.Throw(rv);
    return;
  }

  JSAutoCompartment ac(aCx, aObj);
  JSObject* outView = Uint8Array::Create(
    aCx, utf8.Length(), reinterpret_cast<const uint8_t*>(utf8.BeginReading()));
  if (!outView) {
    aRv.Throw(NS_ERROR_OUT_OF_MEMORY);
    return;
  }

  aRetval.set(outView);
}

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;
}

void
FetchStreamReader::StartConsuming(JSContext* aCx,
                                  JS::HandleObject aStream,
                                  JS::MutableHandle<JSObject*> aReader,
                                  ErrorResult& aRv)
{
  MOZ_DIAGNOSTIC_ASSERT(!mReader);
  MOZ_DIAGNOSTIC_ASSERT(aStream);

  JS::Rooted<JSObject*> reader(aCx,
                               JS::ReadableStreamGetReader(aCx, aStream,
                                                           JS::ReadableStreamReaderMode::Default));
  if (!reader) {
    aRv.StealExceptionFromJSContext(aCx);
    CloseAndRelease(aCx, NS_ERROR_DOM_INVALID_STATE_ERR);
    return;
  }

  mReader = reader;
  aReader.set(reader);

  aRv = mPipeOut->AsyncWait(this, 0, 0, mOwningEventTarget);
  if (NS_WARN_IF(aRv.Failed())) {
    return;
  }
}

void
WebGLExtensionDisjointTimerQuery::GetQueryObjectEXT(JSContext* cx,
                                                    WebGLTimerQuery* query,
                                                    GLenum pname,
                                                    JS::MutableHandle<JS::Value> retval)
{
  if (mIsLost)
    return;

  if (!mContext->ValidateObject("getQueryObjectEXT", query))
    return;

  if (query == mActiveQuery.get()) {
    mContext->ErrorInvalidOperation("getQueryObjectEXT: Query must not be"
                                    " active.");
  }

  mContext->MakeContextCurrent();
  // XXX: Note that the query result *may change* within the same task!
  // This does not follow the specification, which states that all calls
  // checking query results must return the same value until the event loop
  // is empty.
  switch (pname) {
  case LOCAL_GL_QUERY_RESULT_EXT: {
    GLuint64 result = 0;
    mContext->GL()->fGetQueryObjectui64v(query->mGLName,
                                         LOCAL_GL_QUERY_RESULT_EXT,
                                         &result);
    retval.set(JS::NumberValue(result));
    break;
  }
  case LOCAL_GL_QUERY_RESULT_AVAILABLE_EXT: {
    GLuint avail = 0;
    mContext->GL()->fGetQueryObjectuiv(query->mGLName,
                                       LOCAL_GL_QUERY_RESULT_AVAILABLE_EXT,
                                       &avail);
    bool canBeAvailable = query->CanBeAvailable() || gfxPrefs::WebGLImmediateQueries();
    retval.set(JS::BooleanValue(bool(avail) && canBeAvailable));
    break;
  }
  default:
    mContext->ErrorInvalidEnumInfo("getQueryObjectEXT: Invalid query"
                                   " property.", pname);
    break;
  }
}