third_party/blink/renderer/core/frame/remote_dom_window.cc

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "third_party/blink/renderer/core/frame/remote_dom_window.h"

#include "third_party/blink/public/platform/task_type.h"
#include "third_party/blink/renderer/core/dom/document.h"
#include "third_party/blink/renderer/core/events/message_event.h"
#include "third_party/blink/renderer/core/frame/remote_frame_client.h"
#include "third_party/blink/renderer/platform/weborigin/security_origin.h"
#include "third_party/blink/renderer/platform/wtf/functional.h"

namespace blink {

ExecutionContext* RemoteDOMWindow::GetExecutionContext() const {
  return nullptr;
}

void RemoteDOMWindow::Trace(blink::Visitor* visitor) {
  DOMWindow::Trace(visitor);
}

void RemoteDOMWindow::blur() {
  // FIXME: Implement.
}

RemoteDOMWindow::RemoteDOMWindow(RemoteFrame& frame) : DOMWindow(frame) {}

void RemoteDOMWindow::FrameDetached() {
  DisconnectFromFrame();
}

void RemoteDOMWindow::SchedulePostMessage(
    MessageEvent* event,
    scoped_refptr<const SecurityOrigin> target,
    Document* source) {
  // Restrict the user gesture to be forwarded cross-process at most once. This
  // helps avoid unbounded usage of the same user gesture by issuing multiple
  // postMessages to OOPIFs from this process.  A complementary restriction on
  // the receiver side prevents unbounded chaining of user gestures across
  // processes.
  bool has_user_gesture = UserGestureIndicator::ProcessingUserGesture() &&
                          !UserGestureIndicator::WasForwardedCrossProcess();
  if (has_user_gesture)
    UserGestureIndicator::SetWasForwardedCrossProcess();

  // To match same-process behavior, the IPC to forward postMessage
  // cross-process should only be sent after the current script finishes
  // running, to preserve relative ordering of IPCs.  See
  // https://crbug.com/828529.
  //
  // TODO(alexmos, kenrb): PostTask isn't sufficient in some cases, such as
  // when script triggers a layout change after calling postMessage(), which
  // should also be observable by the target frame prior to receiving the
  // postMessage. We might consider forcing layout in ForwardPostMessage or
  // further delaying postMessage forwarding until after the next BeginFrame.
  source->GetTaskRunner(TaskType::kPostedMessage)
      ->PostTask(
          FROM_HERE,
          WTF::Bind(&RemoteDOMWindow::ForwardPostMessage, WrapPersistent(this),
                    WrapPersistent(event), std::move(target),
                    WrapPersistent(source), has_user_gesture));
}

void RemoteDOMWindow::ForwardPostMessage(
    MessageEvent* event,
    scoped_refptr<const SecurityOrigin> target,
    Document* source,
    bool has_user_gesture) {
  // If the target frame was detached after the message was scheduled,
  // don't deliver the message.
  if (!GetFrame())
    return;

  GetFrame()->Client()->ForwardPostMessage(
      event, std::move(target), source->GetFrame(), has_user_gesture);
}

}  // namespace blink