Refactoring of new IPC-only pepper implementation

content/renderer/pepper/pepper_in_process_router.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.
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "ppapi/proxy/connection.h"
+
+namespace content {
+
+class RendererPpapiHostImpl;
+
+// This class fakes an IPC channel so that we can take the new resources with
+// IPC backends and run them in-process.
+//
+// (See pepper_in_process_resource_creation.h for more background.)
+//
+// This class just provides the fake routing for in-process plugins.
+// Asynchronous messages are converted into an asynchronous execution of the
+// message receiver on the opposite end. Synchronous messages just call right
+// through.
+//
+// The resources in ppapi/proxy assume that there is an IPC connection to
+// both the renderer and the browser processes. They take a connection object
+// that includes both of these channels. However, in-process plugins don't
+// have a BrowserPpapiHost on the browser side to receive these messages.
+//
+// As a result, we can't support resources that rely on sending messages to the
+// browser process. Since this class is a stopgap until all interfaces are
+// converted and all plugins are run out-of-procss, we just choose not to
+// support faking IPC channels for resources that send messages directly to the
+// browser process. These resources will just have to use the "old" in-process
+// implementation until the conversion is complete and all this code can be
+// deleted.
+//
+// To keep things consistent, we provide an IPC::Sender for the browser channel
+// in the connection object supplied to resources. This dummy browser channel
+// will just assert and delete the message if anything is ever sent over it.
+class PepperInProcessRouter {
+ public:
+  // The given host parameter owns this class and must outlive us.
+  PepperInProcessRouter(RendererPpapiHostImpl* host_impl);
+  ~PepperInProcessRouter();
+
+  // Returns the dummy sender for the cooresponding end of the in-process
+  // emulated channel.
+  IPC::Sender* GetPluginToRendererSender();
+  IPC::Sender* GetRendererToPluginSender();
+
+  // Returns a connection pair for use by a resource proxy. This includes
+  // the plugin->renderer sender as well as a dummy sender to the browser
+  // process. See the class comment above about the dummy sender.
+  ppapi::proxy::Connection GetPluginConnection();
+
+ private:
+  class DummyBrowserChannel;
+  scoped_ptr<DummyBrowserChannel> dummy_browser_channel_;
+
+  // Renderer -> plugin channel.
+  class HostToPluginRouter;
+  scoped_ptr<HostToPluginRouter> host_to_plugin_router_;
+
+  // Plugin -> renderer channel.
+  class PluginToHostRouter;
+  scoped_ptr<PluginToHostRouter> plugin_to_host_router_;
+
+  DISALLOW_COPY_AND_ASSIGN(PepperInProcessRouter);
+};
+
+}  // namespace content