Browser Plugin: New Implementation (Browser Side)

content/browser/browser_plugin/browser_plugin_embedder.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/browser/browser_plugin/browser_plugin_embedder.h"
+
+#include <set>
+
+#include "base/logging.h"
+#include "base/stl_util.h"
+#include "base/time.h"
+#include "content/browser/browser_plugin/browser_plugin_embedder_helper.h"
+#include "content/browser/browser_plugin/browser_plugin_guest.h"
+#include "content/browser/browser_plugin/browser_plugin_guest_helper.h"
+#include "content/browser/browser_plugin/browser_plugin_host_factory.h"
+#include "content/browser/renderer_host/render_view_host_impl.h"
+#include "content/browser/renderer_host/render_widget_host_impl.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+#include "content/common/browser_plugin_messages.h"
+#include "content/common/view_messages.h"
+#include "content/public/browser/notification_details.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/notification_types.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/render_widget_host_view.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_view.h"
+#include "content/public/common/url_constants.h"
+#include "ui/gfx/size.h"
+
+namespace content {
+
+// static
+BrowserPluginHostFactory* BrowserPluginEmbedder::factory_ = NULL;
+
+BrowserPluginEmbedder::BrowserPluginEmbedder(
+    WebContentsImpl* web_contents,
+    RenderViewHost* render_view_host)
+    : WebContentsObserver(web_contents),
+      render_view_host_(render_view_host) {
+  // Listen to visibility changes so that an embedder hides its guests
+  // as well.
+  registrar_.Add(this,
+                 NOTIFICATION_WEB_CONTENTS_VISIBILITY_CHANGED,
+                 Source<WebContents>(web_contents));
+
+  // |render_view_host| manages the ownership of this BrowserPluginGuestHelper.
+  new BrowserPluginEmbedderHelper(this, render_view_host);
+}
+
+BrowserPluginEmbedder::~BrowserPluginEmbedder() {
+  // Destroy guests that are managed by the current embedder, for more details

[Charlie Reis, 2012/09/13 00:51:44]

nit: These are two separate sentences.  (There have been a lot of run-on
sentences like this in this review, so please keep an eye out for them.)

[lazyboy, 2012/09/13 15:56:23]

Ok.
Done.

+  // see BrowserPluginEmbedder::DidCommitProvisionalLoadForFrame().
+  DestroyGuests();
+}
+
+// static
+BrowserPluginEmbedder* BrowserPluginEmbedder::Create(
+    WebContentsImpl* web_contents,
+    content::RenderViewHost* render_view_host) {
+  if (factory_) {
+    return factory_->CreateBrowserPluginEmbedder(web_contents,
+                                                 render_view_host);
+  }
+  return new BrowserPluginEmbedder(web_contents, render_view_host);
+}
+
+BrowserPluginGuest* BrowserPluginEmbedder::GetGuestByInstanceID(
+    int instance_id) const {
+  ContainerInstanceMap::const_iterator it =
+      guest_web_contents_by_instance_id_.find(instance_id);
+  if (it != guest_web_contents_by_instance_id_.end())
+    return static_cast<WebContentsImpl*>(it->second)->GetBrowserPluginGuest();
+  return NULL;
+}
+
+void BrowserPluginEmbedder::AddGuest(int instance_id,
+                                     WebContents* guest_web_contents,
+                                     int64 frame_id) {
+  DCHECK(guest_web_contents_by_instance_id_.find(instance_id) ==
+         guest_web_contents_by_instance_id_.end());
+  guest_web_contents_by_instance_id_[instance_id] = guest_web_contents;
+  guest_web_contents_container_[guest_web_contents] = frame_id;
+}
+
+void BrowserPluginEmbedder::NavigateGuest(RenderViewHost* render_view_host,
+                                          int instance_id,
+                                          int64 frame_id,
+                                          const std::string& src,
+                                          const gfx::Size& size) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  WebContentsImpl* guest_web_contents = NULL;
+  GURL url(src);
+  if (!guest) {
+    const std::string& host =
+        render_view_host->GetSiteInstance()->GetSite().host();
+    guest_web_contents = WebContentsImpl::CreateGuest(
+        web_contents()->GetBrowserContext(),
+        host,
+        instance_id);
+
+    guest = guest_web_contents->GetBrowserPluginGuest();
+    guest->set_embedder_render_process_host(
+        render_view_host->GetProcess());
+
+    guest_web_contents->GetMutableRendererPrefs()->
+        throttle_input_events = false;
+    AddGuest(instance_id, guest_web_contents, frame_id);
+    guest_web_contents->SetDelegate(guest);
+  } else {
+    guest_web_contents = static_cast<WebContentsImpl*>(guest->web_contents());
+  }
+  guest_web_contents->GetController().LoadURL(url,
+                                              Referrer(),
+                                              PAGE_TRANSITION_AUTO_SUBFRAME,
+                                              std::string());
+  if (!size.IsEmpty())
+    guest_web_contents->GetView()->SizeContents(size);
+}
+
+void BrowserPluginEmbedder::UpdateRectACK(int instance_id,
+                                          int message_id,
+                                          const gfx::Size& size) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  if (guest)
+    guest->UpdateRectACK(message_id, size);
+}
+
+void BrowserPluginEmbedder::ResizeGuest(int instance_id,
+                                        TransportDIB* damage_buffer,
+#if defined(OS_WIN)
+                                        int damage_buffer_size,
+#endif
+                                        int width,
+                                        int height,
+                                        bool resize_pending,
+                                        float scale_factor) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  if (!guest)
+    return;
+  WebContentsImpl* guest_web_contents =
+      static_cast<WebContentsImpl*>(guest->web_contents());
+  guest->SetDamageBuffer(damage_buffer,
+#if defined(OS_WIN)
+                         damage_buffer_size,
+#endif
+                         gfx::Size(width, height),
+                         scale_factor);
+  if (!resize_pending)
+    guest_web_contents->GetView()->SizeContents(gfx::Size(width, height));
+}
+
+void BrowserPluginEmbedder::SetFocus(int instance_id,
+                                     bool focused) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  if (guest)
+    guest->SetFocus(focused);
+}
+
+void BrowserPluginEmbedder::DestroyGuests() {
+  STLDeleteContainerPairFirstPointers(guest_web_contents_container_.begin(),
+                                      guest_web_contents_container_.end());
+  guest_web_contents_container_.clear();
+  guest_web_contents_by_instance_id_.clear();
+}
+
+void BrowserPluginEmbedder::HandleInputEvent(int instance_id,
+                                             RenderViewHost* render_view_host,
+                                             const gfx::Rect& guest_rect,
+                                             const WebKit::WebInputEvent& event,
+                                             IPC::Message* reply_message) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  if (guest)
+    guest->HandleInputEvent(render_view_host, guest_rect, event, reply_message);
+}
+
+void BrowserPluginEmbedder::DestroyGuestByInstanceID(int instance_id) {
+  BrowserPluginGuest* guest = GetGuestByInstanceID(instance_id);
+  if (guest) {
+    WebContents* guest_web_contents = guest->web_contents();
+
+    GuestWebContentsMap::iterator guest_it = guest_web_contents_container_.find(
+        guest_web_contents);
+    DCHECK(guest_it != guest_web_contents_container_.end());
+
+    // Destroy the guest's web_contents.
+    delete guest_it->first;
+
+    guest_web_contents_container_.erase(guest_it);
+    guest_web_contents_by_instance_id_.erase(instance_id);
+  }
+}
+
+void BrowserPluginEmbedder::DidCommitProvisionalLoadForFrame(
+    int64 frame_id,
+    bool is_main_frame,
+    const GURL& url,
+    PageTransition transition_type,
+    RenderViewHost* render_view_host) {
+  // Clean up guests that lie in the frame that we're navigating.
+  //
+  // Subframe's guest(s) clean up is not handled here. They are handled by
+  // either the lifetime of WebContents associated directly with the guest(s) or
+  // by the lifetime of their embedders. Consider the following cases:
+  //
+  // Case 1: (Subframe's guest clean up managed by embedder) A WebContents WC1
+  // embeds a guest (therefore it is an embedder E1), call this guest G1. G1
+  // points to a page that has an iframe. Call the iframe's WebContents WC2. Now
+  // the iframe has a guest of its own in it, lets call it G2, which makes WC2
+  // an embedder as well, call it E2. Now when

[Charlie Reis, 2012/09/13 00:51:44]

Is this possible?  I didn't think we could support guests within guests yet.

[lazyboy, 2012/09/13 15:56:23]

We don't forcefully disallow it yet, but we will disallow it.
See comments below since we plan to remove this function.
(with the following pluginDestroyed(), we would cover guest inside guest too if
we had it).

+  // DidCommitProvisionalLoadForFrame() is called, G2 won't be cleaned up by the
+  // code below since it doesn't directly belong to the top level frame. However
+  // when the WebContents WC2 gets destroyed, it destroys the embedder E2
+  // associated with it, eventually destroying all of its guests (G2).
+  //
+  // Case 2: (Subframe's guest cleanup managed by WebContents) A page has an
+  // iframe which points to a page that has a guest G1. Therefore this makes top
+  // level page's WebContents WC1 an embedder E1. Lets say the WebContents
+  // associated with G1 is WC2. When DidCommitProvisionalLoadForFrame() occurs,
+  // G1 is not a guest within the top level frame that called commit, so it
+  // won't be cleaned up with the code below; However since WC2 goes away, this

[Charlie Reis, 2012/09/13 00:51:44]

How does WC2 go away?  There's no code that I know of that would delete the
guest's WebContents in this case, nor in the case that the top-level page
deletes the iframe.

If there is code for deleting a guest's WebContents when its embedder navigates
or destroys it, then I don't see why the code below is needed.

[lazyboy, 2012/09/13 15:56:23]

I talked to Fady about this part of the code: it seems we don't need this bit of
code anymore.

(WebPlugin's pluginDestroyed() seems to be good enough for handling deletions of
guests)

The fact that I saw WC2 go away was because of BrowserPlugin.pluginDestroyed()
call from renderer (which I wasn't aware of, and Fady says it was added after
this function was added), which removes the BrowserPluginGuest, that deletes WC
associated with the plugin in browser side; Therefore we don't need any special
handling for deleting guests here.
Fady/Charlie: can you think of any other cases we might need this code for?

[Charlie Reis, 2012/09/13 16:55:30]

Great!  I'm not aware of another need for this code if
BrowserPlugin.pluginDestroyed() is cleaning up the guest's WebContents and
BrowserPluginGuest.  Feel free to remove unless Fady thinks otherwise.  Thanks.

[Fady Samuel, 2012/09/13 16:59:57]

I don't believe this code is necessary any more. Please remove it.

[lazyboy, 2012/09/13 18:52:49]

Removed.

+  // eventually destroys G1 since G1 is an observer for WC2.
+  //
+  // The following code is repsonsible for deleting the top-level frame which
+  // will eventually invoke one of the two cases above covering all guests in
+  // the whole frame tree.
+  typedef std::set<WebContents*> GuestSet;
+  GuestSet guests_to_delete;
+  for (GuestWebContentsMap::const_iterator it =
+           guest_web_contents_container_.begin();
+       it != guest_web_contents_container_.end(); ++it) {
+    if (it->second == frame_id)
+      guests_to_delete.insert(it->first);
+  }
+  for (GuestSet::const_iterator it = guests_to_delete.begin();
+       it != guests_to_delete.end(); ++it) {
+    int instance_id = static_cast<WebContentsImpl*>(*it)->
+        GetBrowserPluginGuest()->instance_id();
+    DestroyGuestByInstanceID(instance_id);
+  }
+}
+
+void BrowserPluginEmbedder::RenderViewDeleted(
+    RenderViewHost* render_view_host) {
+  DestroyGuests();
+}
+
+void BrowserPluginEmbedder::RenderViewGone(base::TerminationStatus status) {
+  DestroyGuests();
+}
+
+void BrowserPluginEmbedder::WebContentsVisibilityChanged(bool visible) {
+  // If the embedder is hidden we need to hide the guests as well.
+  for (GuestWebContentsMap::const_iterator it =
+           guest_web_contents_container_.begin();
+       it != guest_web_contents_container_.end(); ++it) {
+    WebContents* web_contents = it->first;
+    if (visible)
+      web_contents->WasShown();
+    else
+      web_contents->WasHidden();
+  }
+}
+
+void BrowserPluginEmbedder::PluginDestroyed(int instance_id) {
+  DestroyGuestByInstanceID(instance_id);
+}
+
+void BrowserPluginEmbedder::Observe(int type,
+                                    const NotificationSource& source,
+                                    const NotificationDetails& details) {
+  switch (type) {
+    case NOTIFICATION_WEB_CONTENTS_VISIBILITY_CHANGED: {
+      bool visible = *Details<bool>(details).ptr();
+      WebContentsVisibilityChanged(visible);
+      break;
+    }
+    default:
+      NOTREACHED() << "Unexpected notification type: " << type;
+  }
+}
+
+}  // namespace content