text: /// Copyright (c) 2012 The Chromium Embedded Framework Authors.
  // Portions (c) 2011 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 "libcef/renderer/render_message_filter.h"
  
  #include "libcef/common/cef_messages.h"
  #include "libcef/renderer/thread_util.h"
  
  #include "base/bind.h"
  #include "base/message_loop/message_loop.h"
  #include "base/task/post_task.h"
  #include "chrome/common/render_messages.h"
  #include "content/public/browser/browser_task_traits.h"
  #include "content/public/browser/browser_thread.h"
  #include "third_party/blink/public/platform/web_string.h"
  #include "third_party/blink/public/web/web_security_policy.h"
  #include "url/gurl.h"
  #include "url/url_util.h"
  
  using content::BrowserThread;
  
  CefRenderMessageFilter::CefRenderMessageFilter() : channel_(NULL) {}
  
  CefRenderMessageFilter::~CefRenderMessageFilter() {}
  
  void CefRenderMessageFilter::OnFilterAdded(IPC::Channel* channel) {
    channel_ = channel;
  }
  
  void CefRenderMessageFilter::OnFilterRemoved() {
    channel_ = nullptr;
  }
  
  bool CefRenderMessageFilter::OnMessageReceived(const IPC::Message& message) {
    bool handled = true;
    IPC_BEGIN_MESSAGE_MAP(CefRenderMessageFilter, message)
      IPC_MESSAGE_HANDLER(ChromeViewHostMsg_IsCrashReportingEnabled,
                          OnIsCrashReportingEnabled)
      IPC_MESSAGE_UNHANDLED(handled = false)
    IPC_END_MESSAGE_MAP()
    return handled;
  }
  
  // Based on BrowserMessageFilter::Send.
  bool CefRenderMessageFilter::Send(IPC::Message* message) {
    if (message->is_sync()) {
      // We don't support sending synchronous messages from the browser.  If we
      // really needed it, we can make this class derive from SyncMessageFilter
      // but it seems better to not allow sending synchronous messages from the
      // browser, since it might allow a corrupt/malicious renderer to hang us.
      NOTREACHED() << "Can't send sync message through CefRenderMessageFilter!";
      return false;
    }
  
    if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
      base::PostTask(FROM_HERE, {content::BrowserThread::IO},
                     base::Bind(base::IgnoreResult(&CefRenderMessageFilter::Send),
                                this, message));
      return true;
    }
  
    if (channel_)
      return channel_->Send(message);
  
    delete message;
    return false;
  }
  
  void CefRenderMessageFilter::OnIsCrashReportingEnabled(bool* enabled) {
    // TODO(cef): Explore whether it's useful for CEF clients to report when crash
    // reporting is enabled.
    *enabled = false;
  }
  