Allow renderer to create pepper ResourceHosts in the browser

content/renderer/pepper/pepper_browser_connection.h

+// Copyright (c) 2013 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.
+
+#ifndef CONTENT_RENDERER_PEPPER_PEPPER_BROWSER_CONNECTION_H_
+#define CONTENT_RENDERER_PEPPER_PEPPER_BROWSER_CONNECTION_H_
+
+#include <map>
+
+#include "base/callback.h"
+#include "content/public/renderer/render_view_observer.h"
+#include "ppapi/c/pp_instance.h"
+
+namespace content {
+
+class RenderView;
+
+// This class represents a connection from the renderer to the browser for
+// sending/receiving pepper ResourceHost related messages. When the browser
+// and renderer communicate about ResourceHosts, they should pass the plugin
+// process ID to identify which plugin they are talking about.
+class PepperBrowserConnection : public RenderViewObserver {
+ public:
+  typedef base::Callback<void(int)> PendingResourceIDCallback;
+
+  explicit PepperBrowserConnection(RenderView* render_view);
+  virtual ~PepperBrowserConnection();
+
+  // RenderViewObserver overrides.
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  // Sends a request to the browser to create a ResourceHost for the given
+  // |instance| of a plugin identified by |child_process_id|. |callback| will be
+  // run when a reply is received with the pending resource ID.
+  void SendBrowserCreate(PP_Instance instance,
+                         int child_process_id,
+                         const IPC::Message& create_message,
+                         PendingResourceIDCallback callback);
+
+ private:
+  // Message handlers.
+  void OnMsgCreateResourceHostFromHostReply(int32_t sequence_number,
+                                            int pending_resource_host_id);
+
+  // Return the next sequence number.
+  int32_t GetNextSequence();
+
+  // Sequence number to track pending callbacks.
+  int32_t next_sequence_number_;
+
+  // Maps a sequence number to the callback to be run.
+  std::map<int32_t, PendingResourceIDCallback> pending_create_map_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperBrowserConnection);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_PEPPER_PEPPER_BROWSER_CONNECTION_H_