Move webkit/plugins/ppapi to content/renderer/pepper.

webkit/plugins/ppapi/message_channel.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.
-
-#ifndef WEBKIT_PLUGINS_PPAPI_MESSAGE_CHANNEL_H_
-#define WEBKIT_PLUGINS_PPAPI_MESSAGE_CHANNEL_H_
-
-#include <deque>
-
-#include "base/memory/weak_ptr.h"
-#include "ppapi/shared_impl/resource.h"
-#include "third_party/WebKit/public/web/WebSerializedScriptValue.h"
-#include "third_party/npapi/bindings/npruntime.h"
-
-struct PP_Var;
-
-namespace webkit {
-namespace ppapi {
-
-class PluginInstanceImpl;
-
-// MessageChannel implements bidirectional postMessage functionality, allowing
-// calls from JavaScript to plugins and vice-versa. See
-// PPB_Messaging::PostMessage and PPP_Messaging::HandleMessage for more
-// information.
-//
-// Currently, only 1 MessageChannel can exist, to implement postMessage
-// functionality for the instance interfaces.  In the future, when we create a
-// MessagePort type in PPAPI, those may be implemented here as well with some
-// refactoring.
-//   - Separate message ports won't require the passthrough object.
-//   - The message target won't be limited to instance, and should support
-//     either plugin-provided or JS objects.
-// TODO(dmichael):  Add support for separate MessagePorts.
-class MessageChannel {
- public:
-  // MessageChannelNPObject is a simple struct that adds a pointer back to a
-  // MessageChannel instance.  This way, we can use an NPObject to allow
-  // JavaScript interactions without forcing MessageChannel to inherit from
-  // NPObject.
-  struct MessageChannelNPObject : public NPObject {
-    MessageChannelNPObject();
-    ~MessageChannelNPObject();
-
-    base::WeakPtr<MessageChannel> message_channel;
-  };
-
-  explicit MessageChannel(PluginInstanceImpl* instance);
-  ~MessageChannel();
-
-  // Post a message to the onmessage handler for this channel's instance
-  // asynchronously.
-  void PostMessageToJavaScript(PP_Var message_data);
-  // Post a message to the PPP_Instance HandleMessage function for this
-  // channel's instance.
-  void PostMessageToNative(PP_Var message_data);
-
-  // Return the NPObject* to which we should forward any calls which aren't
-  // related to postMessage.  Note that this can be NULL;  it only gets set if
-  // there is a scriptable 'InstanceObject' associated with this channel's
-  // instance.
-  NPObject* passthrough_object() {
-    return passthrough_object_;
-  }
-  void SetPassthroughObject(NPObject* passthrough);
-
-  NPObject* np_object() { return np_object_; }
-
-  PluginInstanceImpl* instance() {
-    return instance_;
-  }
-
-  // Messages sent to JavaScript are queued by default. After the DOM is
-  // set up for the plugin, users of MessageChannel should call
-  // StopQueueingJavaScriptMessages to start dispatching messages to JavaScript.
-  void QueueJavaScriptMessages();
-  void StopQueueingJavaScriptMessages();
-
- private:
-  PluginInstanceImpl* instance_;
-
-  // We pass all non-postMessage calls through to the passthrough_object_.
-  // This way, a plugin can use PPB_Class or PPP_Class_Deprecated and also
-  // postMessage.  This is necessary to support backwards-compatibility, and
-  // also trusted plugins for which we will continue to support synchronous
-  // scripting.
-  NPObject* passthrough_object_;
-
-  // The NPObject we use to expose postMessage to JavaScript.
-  MessageChannelNPObject* np_object_;
-
-  // Post a message to the onmessage handler for this channel's instance
-  // synchronously.  This is used by PostMessageToJavaScript.
-  void PostMessageToJavaScriptImpl(
-      const WebKit::WebSerializedScriptValue& message_data);
-  // Post a message to the PPP_Instance HandleMessage function for this
-  // channel's instance.  This is used by PostMessageToNative.
-  void PostMessageToNativeImpl(PP_Var message_data);
-
-  void DrainEarlyMessageQueue();
-
-  // This is used to ensure pending tasks will not fire after this object is
-  // destroyed.
-  base::WeakPtrFactory<MessageChannel> weak_ptr_factory_;
-
-  // TODO(teravest): Remove all the tricky DRAIN_CANCELLED logic once
-  // webkit::ppapi::PluginInstance::ResetAsProxied() is gone.
-  std::deque<WebKit::WebSerializedScriptValue> early_message_queue_;
-  enum EarlyMessageQueueState {
-    QUEUE_MESSAGES,       // Queue JS messages.
-    SEND_DIRECTLY,        // Post JS messages directly.
-    DRAIN_PENDING,        // Drain queue, then transition to DIRECT.
-    DRAIN_CANCELLED       // Preempt drain, go back to QUEUE.
-  };
-  EarlyMessageQueueState early_message_queue_state_;
-
-  DISALLOW_COPY_AND_ASSIGN(MessageChannel);
-};
-
-}  // namespace ppapi
-}  // namespace webkit
-
-#endif  // WEBKIT_PLUGINS_PPAPI_MESSAGE_CHANNEL_H_