Browser Plugin: New Implementation (Browser Side)

content/browser/browser_plugin/browser_plugin_guest.h

+// 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.
+
+// A BrowserPluginGuest represents the browser side of browser <--> renderer

[awong, 2012/09/07 20:51:03]

This comment block could use some paragraphs breaks (with newlines between
paragraphs).

[lazyboy, 2012/09/08 02:12:22]

Done.

+// communication (a browser plugin (which is a WebPlugin) is on the renderer

[awong, 2012/09/07 20:51:03]

Make the parenthetical statement its own sentence.  Nested parenthesis == new
sentence ;)

Also clarify that this is browser <--> guest renderer, and that a "guest"
renderer is a <browser> tag.

The target audience will be maintainers who might know chrome, but know
BrowserPlugin so assume that knowledge level.

[lazyboy, 2012/09/08 02:12:22]

Done.

+// side). It lives on the UI thread of the browser process.  It has a helper,
+// BrowserPluginGuestHelper, which is a RenderViewHostObserver.  The helper
+// object receives messages (RenderViewHostMsg_*) directed at the browser plugin

[awong, 2012/09/07 20:51:03]

Is there a way to know which RenderViewHostMsg_* we want to listen for
specifically?  Do we just want to grab each message that has analogous handler
in WebPlugin?

Stating the constraint would be useful for future maintainers who want to modify
or validate the implementation.

[lazyboy, 2012/09/08 02:12:22]

Fady can you answer this one? Thanks.

[Fady Samuel, 2012/09/10 16:24:11]

Firstly, I believe that should say ViewHostMsg_* rather than
RenderViewHostMsg_*.

Secondly, I don't have a simple answer to this question.

Basically, anything the embedder might be interested in knowing or modifying
about the guest should be listened for here. 

[awong, 2012/09/10 19:21:07]

Yeah...you're right. feel free to ignore my comment.

[lazyboy, 2012/09/10 23:40:56]

Fixed the note here saying ViewHostMsg_* instead of RenderViewHostMsg*_; also
added the comment saying we intercept anything that is interesting.

+// and redirects them to this class. Since BrowserPlugin is a WebPlugin, we need
+// to provide overriden behaviors for messages like handleInputEvent,
+// updateGeometry. Such messages gets routed into BrowserPluginGuest via its
+// embedder (BrowserPluginEmbedder). These are BrowserPluginHost_* messages sent
+// from the BrowserPlugin.
+// It knows about its embedder process, communication to renderer happens

[awong, 2012/09/07 20:51:03]

s/It/BrowserPluginGuest/

Otherwise the antecedent is very ambiguous.

[lazyboy, 2012/09/08 02:12:22]

Done.

+// through the embedder process.
+// A BrowserPluginGuest is also associated directly with the WebContents related
+// to the BrowserPlugin, its a WebContentsDelegate and WebContentsObserver for

[awong, 2012/09/07 20:51:03]

, its -> . It is

[lazyboy, 2012/09/08 02:12:22]

Done.

+// it.

[awong, 2012/09/07 20:51:03]

"it" twice in one sentence referring to 2 different things == ambiguous
antecedent again :)

Refer to both by their full names to be completely clear.

[lazyboy, 2012/09/08 02:12:22]

Done.

+
+#ifndef CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_H_
+#define CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_H_
+
+#include <string>
+#include <map>
+
+#include "base/compiler_specific.h"
+#include "base/id_map.h"
+#include "content/browser/browser_plugin/browser_plugin_host_factory.h"
+#include "content/public/browser/render_view_host_observer.h"
+#include "content/public/browser/web_contents_delegate.h"
+#include "content/public/browser/web_contents_observer.h"
+#include "ipc/ipc_channel_handle.h"
+#include "ipc/ipc_sync_message.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
+#include "ui/surface/transport_dib.h"
+#include "ui/gfx/rect.h"
+#include "ui/gfx/size.h"
+#include "webkit/glue/webcursor.h"
+
+namespace gfx {
+class Size;
+}
+
+struct BrowserPluginHostMsg_ResizeGuest_Params;
+struct ViewHostMsg_UpdateRect_Params;
+
+namespace content {
+
+class BrowserPluginHostFactory;
+class BrowserPluginEmbedder;
+class RenderProcessHost;
+
+// A browser plugin guest provides functionality for WebContents to operate in
+// the guest role and implements guest specific overrides for ViewHostMsg_*
+// messages.

[awong, 2012/09/07 20:51:03]

Newline between paragraphs.  Please fix here and in other comment blocks.

[lazyboy, 2012/09/08 02:12:22]

Done.

+// BrowserPluginEmbedder is responsible for creating and destroying a guest.
+class CONTENT_EXPORT BrowserPluginGuest : public WebContentsDelegate,
+                                          public WebContentsObserver {
+ public:
+  virtual ~BrowserPluginGuest();
+
+  static BrowserPluginGuest* Create(int instance_id,
+                                    WebContentsImpl* web_contents,
+                                    content::RenderViewHost* render_view_host);
+
+  // Overrides factory for testing. Default (NULL) value indicates regular
+  // (non-test) environment.
+  static void set_factory_for_testing(BrowserPluginHostFactory* factory) {
+    content::BrowserPluginGuest::factory_ = factory;
+  }
+
+  // WebContentsObserver implementation.
+  virtual void DidCommitProvisionalLoadForFrame(
+      int64 frame_id,
+      bool is_main_frame,
+      const GURL& url,
+      PageTransition transition_type,
+      RenderViewHost* render_view_host) OVERRIDE;
+  virtual void RenderViewGone(base::TerminationStatus status) OVERRIDE;
+
+  // WebContentsDelegate implementation.
+  virtual void RendererUnresponsive(WebContents* source) OVERRIDE;
+
+ private:
+  friend class BrowserPluginEmbedder;
+  friend class BrowserPluginGuestHelper;
+  friend class TestBrowserPluginGuest;
+
+  BrowserPluginGuest(int instance_id,
+                     WebContentsImpl* web_contents,
+                     RenderViewHost* render_view_host);
+
+  void set_embedder_render_process_host(
+      RenderProcessHost* render_process_host) {
+    embedder_render_process_host_ = render_process_host;
+  }
+  RenderProcessHost* embedder_render_process_host() {
+    return embedder_render_process_host_;
+  }
+  // Returns the identifier that uniquely identifies a browser plugin guest
+  // within an embedder.
+  int instance_id() const { return instance_id_; }
+
+  void SetDamageBuffer(TransportDIB* damage_buffer,
+                       const gfx::Size& size,
+                       float scale_factor);
+  TransportDIB* damage_buffer() const { return damage_buffer_.get(); }
+  const gfx::Size& damage_buffer_size() const { return damage_buffer_size_; }
+  float damage_buffer_scale_factor() const {
+    return damage_buffer_scale_factor_;
+  }
+
+  void UpdateRect(RenderViewHost* render_view_host,
+                  const ViewHostMsg_UpdateRect_Params& params);
+  void UpdateRectACK(int message_id, const gfx::Size& size);
+  // Handles input event routed through the embedder (which is initiated in the
+  // browser plugin (renderer side of the embedder)).
+  void HandleInputEvent(RenderViewHost* render_view_host,
+                        const gfx::Rect& guest_rect,
+                        const WebKit::WebInputEvent& event,
+                        IPC::Message* reply_message);
+  // Overrides default ShowWidget message so we show them on the correct
+  // coordinates.
+  void ShowWidget(RenderViewHost* render_view_host,
+                  int route_id,
+                  const gfx::Rect& initial_pos);
+  void SetFocus(bool focused);
+  void SetCursor(const WebCursor& cursor);
+  // Handles input event acks so they are sent to browser plugin host (via
+  // embedder) instead of default view/widget host.
+  void HandleInputEventAck(RenderViewHost* render_view_host, bool handled);
+
+  void Destroy();
+
+  // Helper to send messages to embedder. Overriden in test implementation since
+  // we want to intercept certain messages for testing.
+  virtual void SendMessageToEmbedder(IPC::Message*);
+
+  // Static factory instance (always NULL for non-test).
+  static content::BrowserPluginHostFactory* factory_;
+
+  bool ViewTakeFocus(bool reverse);
+
+  RenderProcessHost* embedder_render_process_host_;
+  // An identifier that uniquely identifies a browser plugin guest within an
+  // embedder.
+  int instance_id_;
+  scoped_ptr<TransportDIB> damage_buffer_;
+  gfx::Size damage_buffer_size_;
+  float damage_buffer_scale_factor_;
+  scoped_ptr<IPC::Message> pending_input_event_reply_;
+  gfx::Rect guest_rect_;
+  WebCursor cursor_;
+  IDMap<RenderViewHost> pending_updates_;
+  int pending_update_counter_;
+
+  DISALLOW_COPY_AND_ASSIGN(BrowserPluginGuest);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BROWSER_PLUGIN_BROWSER_PLUGIN_GUEST_H_