Support frame tree propagation between renderers in the same browsing instance.

content/renderer/render_view_impl.cc

 // Copyright (c) 2012 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 "content/renderer/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/compiler_specific.h"
+#include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/lazy_instance.h"
 #include "base/message_loop_proxy.h"
 #include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/process_util.h"
 #include "base/string_number_conversions.h"
 #include "base/string_piece.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/sys_string_conversions.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "content/common/appcache/appcache_dispatcher.h"
 #include "content/common/child_thread.h"
 #include "content/common/clipboard_messages.h"
 #include "content/common/database_messages.h"
 #include "content/common/drag_messages.h"
 #include "content/common/fileapi/file_system_dispatcher.h"
 #include "content/common/fileapi/webfilesystem_callback_dispatcher.h"
 #include "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
 #include "content/common/intents_messages.h"
 #include "content/common/java_bridge_messages.h"
 #include "content/common/old_browser_plugin_messages.h"
 #include "content/common/pepper_messages.h"
 #include "content/common/pepper_plugin_registry.h"
 #include "content/common/quota_dispatcher.h"
 #include "content/common/request_extra_data.h"
 #include "content/common/socket_stream_handle_data.h"
+#include "content/common/renderer_constants.h"
 #include "content/common/view_messages.h"
 #include "content/common/webmessageportchannel_impl.h"
 #include "content/public/common/bindings_policy.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_constants.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/context_menu_params.h"
 #include "content/public/common/file_chooser_params.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/renderer/content_renderer_client.h"
@@ skipping 283 matching lines @@
 
 static const float kScalingIncrement = 0.1f;
 
 static const float kScalingIncrementForGesture = 0.01f;
 
 static RenderViewImpl* FromRoutingID(int32 routing_id) {
   return static_cast<RenderViewImpl*>(
       ChildThread::current()->ResolveRoute(routing_id));
 }
 
+static WebKit::WebFrame* FindFrameByID(WebKit::WebFrame* root, int frame_id) {
+  for (WebFrame* frame = root; frame; frame = frame->traverseNext(false))

[Charlie Reis, 2012/08/22 22:08:34]

nit: This for loop needs braces.

[nasko, 2012/08/23 21:55:53]

Done.

+    if (frame->identifier() == frame_id)
+      return frame;
+  return NULL;
+}
+
 static void GetRedirectChain(WebDataSource* ds, std::vector<GURL>* result) {
   WebVector<WebURL> urls;
   ds->redirectChain(urls);
   result->reserve(urls.size());
   for (size_t i = 0; i < urls.size(); ++i)
     result->push_back(urls[i]);
 }
 
 // If |data_source| is non-null and has a DocumentState associated with it,
 // the AltErrorPageResourceFetcher is reset.
@@ skipping 84 matching lines @@
     if (!opener) {
       return true;
     }
 
     if (url.GetOrigin() != GURL(opener->document().url()).GetOrigin())
       return true;
   }
   return false;
 }
 
+// Recursively walks the frame tree and serializes it to JSON as described in
+// the comment for ViewMsg_UpdateFrameTree.
+static void ConstructFrameTree(WebKit::WebFrame* frame,
+                      WebKit::WebFrame* exclude_subtree,

[Charlie Reis, 2012/08/22 22:08:34]

nit: Wrong indent.

Also, what is this parameter for?

[nasko, 2012/08/23 21:55:53]

Done.

+                      base::DictionaryValue* dict) {
+  dict->SetString(content::kFrameTreeNodeNameKey,
+                  UTF16ToUTF8(frame->assignedName()).c_str());
+  dict->SetInteger(content::kFrameTreeNodeIdKey, frame->identifier());
+
+  WebFrame* child = frame->firstChild();
+  ListValue* children = new ListValue();
+  for (; child; child = child->nextSibling()) {
+    if (child == exclude_subtree)
+      continue;
+
+    base::DictionaryValue* d = new base::DictionaryValue();
+    ConstructFrameTree(child, exclude_subtree, d);
+    children->Append(d);
+  }
+  if (children->GetSize() > 0) {

[Charlie Reis, 2012/08/22 22:08:34]

nit: No braces on one-line if.

[nasko, 2012/08/23 21:55:53]

Done.

+    dict->Set(content::kFrameTreeNodeSubtreeKey, children);
+  }
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 struct RenderViewImpl::PendingFileChooser {
   PendingFileChooser(const content::FileChooserParams& p,
                      WebFileChooserCompletion* c)
       : params(p),
         completion(c) {
   }
   content::FileChooserParams params;
   WebFileChooserCompletion* completion;  // MAY BE NULL to skip callback.
@@ skipping 89 matching lines @@
       java_bridge_dispatcher_(NULL),
       mouse_lock_dispatcher_(NULL),
       session_storage_namespace_id_(session_storage_namespace_id),
       handling_select_range_(false),
 #if defined(OS_WIN)
       focused_plugin_id_(-1),
 #endif
       guest_to_embedder_channel_(guest_to_embedder_channel),
       guest_pp_instance_(0),
       guest_uninitialized_context_(NULL),
+      updating_frame_tree_(false),
+      pending_frame_tree_update_(false),
+      target_process_id_(0),
+      target_routing_id_(0),
       ALLOW_THIS_IN_INITIALIZER_LIST(pepper_delegate_(this)) {
   set_throttle_input_events(renderer_prefs.throttle_input_events);
   routing_id_ = routing_id;
   surface_id_ = surface_id;
   if (opener_id != MSG_ROUTING_NONE && is_renderer_created)
     opener_id_ = opener_id;
 
   // Ensure we start with a valid next_page_id_ from the browser.
   DCHECK_GE(next_page_id_, 0);
 
@@ skipping 74 matching lines @@
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(switches::kDomAutomationController))
     enabled_bindings_ |= content::BINDINGS_POLICY_DOM_AUTOMATION;
 
   ProcessViewLayoutFlags(command_line);
 
   content::GetContentClient()->renderer()->RenderViewCreated(this);
 
   // If we have an opener_id but we weren't created by a renderer, then
   // it's the browser asking us to set our opener to another RenderView.
-  // TODO(creis): This doesn't yet handle openers that are subframes.
   if (opener_id != MSG_ROUTING_NONE && !is_renderer_created) {
     RenderViewImpl* opener_view = FromRoutingID(opener_id);
     if (opener_view)
       webview()->mainFrame()->setOpener(opener_view->webview()->mainFrame());
   }
 
   // If we are initially swapped out, navigate to kSwappedOutURL.
   // This ensures we are in a unique origin that others cannot script.
   if (is_swapped_out_)
-    NavigateToSwappedOutURL();
+    NavigateToSwappedOutURL(webview()->mainFrame(), NULL);
 }
 
 RenderViewImpl::~RenderViewImpl() {
   history_page_ids_.clear();
 
   if (decrement_shared_popup_at_destruction_)
     shared_popup_counter_->data--;
 
   // If file chooser is still waiting for answer, dispatch empty answer.
   while (!file_chooser_completions_.empty()) {
@@ skipping 282 matching lines @@
     IPC_MESSAGE_HANDLER(ViewMsg_ContextMenuClosed, OnContextMenuClosed)
     // TODO(viettrungluu): Move to a separate message filter.
 #if defined(OS_MACOSX)
     IPC_MESSAGE_HANDLER(ViewMsg_SetInLiveResize, OnSetInLiveResize)
 #endif
     IPC_MESSAGE_HANDLER(ViewMsg_SetHistoryLengthAndPrune,
                         OnSetHistoryLengthAndPrune)
     IPC_MESSAGE_HANDLER(ViewMsg_EnableViewSourceMode, OnEnableViewSourceMode)
     IPC_MESSAGE_HANDLER(JavaBridgeMsg_Init, OnJavaBridgeInit)
     IPC_MESSAGE_HANDLER(ViewMsg_SetAccessibilityMode, OnSetAccessibilityMode)
+    IPC_MESSAGE_HANDLER(ViewMsg_UpdateFrameTree, OnUpdatedFrameTree)
 
     // Have the super handle all other messages.
     IPC_MESSAGE_UNHANDLED(handled = RenderWidget::OnMessageReceived(message))
   IPC_END_MESSAGE_MAP()
 
   if (!msg_is_ok) {
     // The message had a handler, but its deserialization failed.
     // Kill the renderer to avoid potential spoofing attacks.
     CHECK(false) << "Unable to deserialize message in RenderViewImpl.";
   }
@@ skipping 883 matching lines @@
   // NOTE: For now we're doing the safest thing, and sending out notification
   // when done loading. This currently isn't an issue as the favicon is only
   // displayed when done loading. Ideally we would send notification when
   // finished parsing the head, but webkit doesn't support that yet.
   // The feed discovery code would also benefit from access to the head.
   Send(new ViewHostMsg_DidStopLoading(routing_id_));
 
   if (load_progress_tracker_ != NULL)
     load_progress_tracker_->DidStopLoading();
 
+  if (pending_frame_tree_update_) {
+    pending_frame_tree_update_ = false;
+    SendUpdatedFrameTree(webview()->mainFrame(), false);
+  }
+
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, DidStopLoading());
 }
 
 void RenderViewImpl::didChangeLoadProgress(WebFrame* frame,
                                            double load_progress) {
   if (load_progress_tracker_ != NULL)
     load_progress_tracker_->DidChangeLoadProgress(frame, load_progress);
 }
 
 bool RenderViewImpl::isSmartInsertDeleteEnabled() {
@@ skipping 564 matching lines @@
     return NULL;
   return new RendererWebApplicationCacheHostImpl(
       FromWebView(frame->view()), client,
       RenderThreadImpl::current()->appcache_dispatcher()->backend_proxy());
 }
 
 WebCookieJar* RenderViewImpl::cookieJar(WebFrame* frame) {
   return &cookie_jar_;
 }
 
+void RenderViewImpl::didCreateFrame(WebFrame* parent, WebFrame* child) {
+  if (is_loading_) {
+    pending_frame_tree_update_ = true;
+    return;
+  }
+  if (!updating_frame_tree_) {

[Charlie Reis, 2012/08/22 22:08:34]

nit: No braces.

[nasko, 2012/08/23 21:55:53]

Done.

+    SendUpdatedFrameTree(child, false);
+  }
+}
+
 void RenderViewImpl::frameDetached(WebFrame* frame) {
+  if (is_loading_) {
+    pending_frame_tree_update_ = true;
+    return;
+  }
+  if (!updating_frame_tree_) {
+    SendUpdatedFrameTree(frame, true);
+  }
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, FrameDetached(frame));
 }
 
 void RenderViewImpl::willClose(WebFrame* frame) {
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, FrameWillClose(frame));
 }
 
 void RenderViewImpl::loadURLExternally(
     WebFrame* frame, const WebURLRequest& request,
     WebNavigationPolicy policy) {
@@ skipping 1132 matching lines @@
 
     if (!context->Initialize(
             attributes,
             false /* bind generates resources */,
             content::CAUSE_FOR_GPU_LAUNCH_WEBGRAPHICSCONTEXT3DCOMMANDBUFFERIMPL_INITIALIZE))
       return NULL;
     return context.release();
   }
 }
 
+// The browser process needs to know the shape of the tree, as well as the names
+// and ids of all frames. This allows it to properly route JavaScript messages
+// across processes and frames. The serialization format is described in the
+// comments of the ViewMsg_FrameTreeUpdated message.
+// This function sends a those updates to the browser and updates the RVH

[Charlie Reis, 2012/08/22 22:08:34]

nit: sends those

[nasko, 2012/08/23 21:55:53]

Done.

+// corresponding to this object. It must be called on any events that modify
+// the tree structure or the names of any frames.
+void RenderViewImpl::SendUpdatedFrameTree(
+    WebKit::WebFrame* frame, bool exclude_subtree) {
+  std::string json;
+  WebFrame* f = frame->top();
+  base::DictionaryValue tree;
+
+  ConstructFrameTree(f, exclude_subtree ? frame : NULL, &tree);
+  base::JSONWriter::Write(&tree, &json);
+
+  Send(new ViewHostMsg_FrameTreeUpdated(routing_id_, json));
+}
+
 void RenderViewImpl::EnsureMediaStreamImpl() {
   if (!RenderThreadImpl::current())  // Will be NULL during unit tests.
     return;
 
 #if defined(ENABLE_WEBRTC)
   if (!p2p_socket_dispatcher_)
     p2p_socket_dispatcher_ = new content::P2PSocketDispatcher(this);
 
   if (!media_stream_dispatcher_)
     media_stream_dispatcher_ = new MediaStreamDispatcher(this);
@@ skipping 195 matching lines @@
     }
     delete channels;
   }
 
   int id = intents_host_->RegisterWebIntent(intentRequest);
   Send(new IntentsHostMsg_WebIntentDispatch(
       routing_id_, intent_data, id));
 }
 
 bool RenderViewImpl::willCheckAndDispatchMessageEvent(
-    WebKit::WebFrame* source,
+    WebKit::WebFrame* sourceFrame,
+    WebKit::WebFrame* targetFrame,
     WebKit::WebSecurityOrigin target_origin,
     WebKit::WebDOMMessageEvent event) {
   if (!is_swapped_out_)
     return false;
 
   ViewMsg_PostMessage_Params params;
   params.data = event.data().toString();
   params.source_origin = event.origin();
   if (!target_origin.isNull())
     params.target_origin = target_origin.toString();
 
   // Include the routing ID for the source frame, which the browser process
   // will translate into the routing ID for the equivalent frame in the target
   // process.
-  // TODO(creis): Support source subframes.
   params.source_routing_id = MSG_ROUTING_NONE;
-  RenderViewImpl* source_view = FromWebView(source->view());
+  RenderViewImpl* source_view = FromWebView(sourceFrame->view());
   if (source_view)
     params.source_routing_id = source_view->routing_id();
+  params.source_frame_id = sourceFrame->identifier();
+
+  // Include the process, route, and frame IDs of the target frame. This allows
+  // the browser to detect races between this message being sent and the target
+  // frame no longer being valid.
+  params.target_process_id = target_process_id_;
+  params.target_routing_id = target_routing_id_;
+
+  std::map<int,int>::iterator it = frames_map_.find(targetFrame->identifier());
+  if (it != frames_map_.end()) {

[Charlie Reis, 2012/08/22 22:08:34]

nit: no braces

[nasko, 2012/08/23 21:55:53]

Done.

+    params.target_frame_id = it->second;
+  } else {
+    params.target_frame_id = 0;
+  }
 
   Send(new ViewHostMsg_RouteMessageEvent(routing_id_, params));
   return true;
 }
 
 void RenderViewImpl::willOpenSocketStream(
     WebSocketStreamHandle* handle) {
   SocketStreamHandleData::AddToHandle(handle, routing_id_);
 }
 
@@ skipping 709 matching lines @@
 
 void RenderViewImpl::OnScriptEvalRequest(const string16& frame_xpath,
                                          const string16& jscript,
                                          int id,
                                          bool notify_result) {
   EvaluateScript(frame_xpath, jscript, id, notify_result);
 }
 
 void RenderViewImpl::OnPostMessageEvent(
     const ViewMsg_PostMessage_Params& params) {
-  // TODO(creis): Support sending to subframes.
-  WebFrame* frame = webview()->mainFrame();
+  // Find the frame, which is a target of this message. The source tags the

[Charlie Reis, 2012/08/22 22:08:34]

nit: Find the target frame of this message.

[nasko, 2012/08/23 21:55:53]

Done.

+  // message with |remote_frame_id|, so use it to locate the frame.
+  WebFrame* frame = FindFrameByID(webview()->mainFrame(),
+                                  params.target_frame_id);
+  if (!frame)
+    return;
 
   // Find the source frame if it exists.
-  // TODO(creis): Support source subframes.
   WebFrame* source_frame = NULL;
   if (params.source_routing_id != MSG_ROUTING_NONE) {
     RenderViewImpl* source_view = FromRoutingID(params.source_routing_id);
     if (source_view)
-      source_frame = source_view->webview()->mainFrame();
+      source_frame = source_view->GetFrameByRemoteID(params.source_frame_id);
   }
 
   // Create an event with the message.  The final parameter to initMessageEvent
   // is the last event ID, which is not used with postMessage.
   WebDOMEvent event = frame->document().createEvent("MessageEvent");
   WebDOMMessageEvent msg_event = event.to<WebDOMMessageEvent>();
   msg_event.initMessageEvent("message",
                              // |canBubble| and |cancellable| are always false
                              false, false,
                              WebSerializedScriptValue::fromString(params.data),
@@ skipping 328 matching lines @@
     // Synchronously run the unload handler before sending the ACK.
     webview()->dispatchUnloadEvent();
 
     // Swap out and stop sending any IPC messages that are not ACKs.
     SetSwappedOut(true);
 
     // Replace the page with a blank dummy URL. The unload handler will not be
     // run a second time, thanks to a check in FrameLoader::stopLoading.
     // TODO(creis): Need to add a better way to do this that avoids running the
     // beforeunload handler. For now, we just run it a second time silently.
-    NavigateToSwappedOutURL();
+    NavigateToSwappedOutURL(webview()->mainFrame(), NULL);
 
     // Let WebKit know that this view is hidden so it can drop resources and
     // stop compositing.
     webview()->setVisibilityState(WebKit::WebPageVisibilityStateHidden, false);
   }
 
   // Just echo back the params in the ACK.
   Send(new ViewHostMsg_SwapOut_ACK(routing_id_, params));
 }
 
-void RenderViewImpl::NavigateToSwappedOutURL() {
+void RenderViewImpl::NavigateToSwappedOutURL(
+    WebKit::WebFrame* frame,
+    base::DictionaryValue* frame_tree) {
   // We use loadRequest instead of loadHTMLString because the former commits
   // synchronously.  Otherwise a new navigation can interrupt the navigation
   // to content::kSwappedOutURL. If that happens to be to the page we had been
   // showing, then WebKit will never send a commit and we'll be left spinning.
   GURL swappedOutURL(content::kSwappedOutURL);
   WebURLRequest request(swappedOutURL);
-  webview()->mainFrame()->loadRequest(request);
+  frame->loadRequest(request);
+
+  // If a frame tree is specified, recursively recreate it using the data

[Charlie Reis, 2012/08/22 22:08:34]

I feel weird about putting this logic in this function, since it doesn't really
have much to do with the original purpose or name.

Maybe we should have a separate recursive function that simply calls
NavigateToSwappedOutURL(frame) as its first action?

[nasko, 2012/08/23 21:55:53]

Separated it into a separate function. Fits much better.

+  // in the current DictionaryValue.
+  if (frame_tree == NULL)
+    return;
+
+  string16 name;
+  if (frame_tree->GetString(content::kFrameTreeNodeNameKey, &name) &&
+      name != string16())

[Charlie Reis, 2012/08/22 22:08:34]

nit: Needs braces.

[nasko, 2012/08/23 21:55:53]

Done.

+    frame->setName(name);
+
+  int remote_id;
+  if (frame_tree->GetInteger(content::kFrameTreeNodeIdKey, &remote_id))
+    frames_map_.insert(std::pair<int, int>(frame->identifier(), remote_id));
+
+  ListValue* children;
+  if (!frame_tree->GetList(content::kFrameTreeNodeSubtreeKey, &children))
+    return;
+
+  base::DictionaryValue* child;
+  for (size_t i = 0; i < children->GetSize(); ++i) {
+    if (!children->GetDictionary(i, &child))
+      continue;
+    WebElement element = frame->document().createElement("iframe");
+    if (frame->document().body().appendChild(element)) {
+      WebFrame* subframe = WebFrame::fromFrameOwnerElement(element);
+      if (subframe) {

[Charlie Reis, 2012/08/22 22:08:34]

nit: No braces.

[nasko, 2012/08/23 21:55:53]

Done.

+        NavigateToSwappedOutURL(subframe, child);
+      }
+    }
+  }
 }
 
 void RenderViewImpl::OnClosePage() {
   FOR_EACH_OBSERVER(RenderViewObserver, observers_, ClosePage());
   // TODO(creis): We'd rather use webview()->Close() here, but that currently
   // sets the WebView's delegate_ to NULL, preventing any JavaScript dialogs
   // in the onunload handler from appearing.  For now, we're bypassing that and
   // calling the FrameLoader's CloseURL method directly.  This should be
   // revisited to avoid having two ways to close a page.  Having a single way
   // to close that can run onunload is also useful for fixing
@@ skipping 839 matching lines @@
 bool RenderViewImpl::WebWidgetHandlesCompositorScheduling() const {
   return !!RenderThreadImpl::current()->compositor_thread();
 }
 
 void RenderViewImpl::OnJavaBridgeInit() {
   DCHECK(!java_bridge_dispatcher_);
 #if defined(ENABLE_JAVA_BRIDGE)
   java_bridge_dispatcher_ = new JavaBridgeDispatcher(this);
 #endif
 }
+
+void RenderViewImpl::OnUpdatedFrameTree(
+    int process_id,
+    int route_id,
+    const std::string& frame_tree) {
+  base::DictionaryValue* frames = NULL;
+  scoped_ptr<base::Value> tree(base::JSONReader::Read(frame_tree));
+  if (tree.get() != NULL && tree->IsType(base::Value::TYPE_DICTIONARY))

[Charlie Reis, 2012/08/22 22:08:34]

nit: You don't need "!= NULL"

[nasko, 2012/08/23 21:55:53]

Done.

+    tree->GetAsDictionary(&frames);
+
+  updating_frame_tree_ = true;
+  frames_map_.clear();
+
+  target_process_id_ = process_id;
+  target_routing_id_ = route_id;
+  NavigateToSwappedOutURL(webview()->mainFrame(), frames);
+
+  updating_frame_tree_ = false;
+}
+
+WebKit::WebFrame* RenderViewImpl::GetFrameByRemoteID(int remote_frame_id) {
+  WebKit::WebFrame* frame = NULL;
+
+  std::map<int, int>::iterator it = frames_map_.find(remote_frame_id);
+  if (it == frames_map_.end())
+    return NULL;
+
+  for (WebFrame* f = webview()->mainFrame(); f; f = f->traverseNext(false))

[Charlie Reis, 2012/08/22 22:08:34]

This part is just FindFrameByID, right?  No sense in duplicating the code.

[nasko, 2012/08/23 21:55:53]

Yes, indeed.

+    if (f->identifier() == it->second)
+      frame = f;
+
+  return frame;
+}