Moved ExtensionMessage* into extensions namespace

chrome/browser/extensions/extension_message_service.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 CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_SERVICE_H_
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_SERVICE_H_
-
-#include <map>
-#include <set>
-#include <string>
-
-#include "base/compiler_specific.h"
-#include "base/memory/linked_ptr.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-
-class ExtensionHost;
-class Profile;
-
-namespace content {
-class RenderProcessHost;
-class WebContents;
-}
-
-namespace extensions {
-class LazyBackgroundTaskQueue;
-}
-
-// This class manages message and event passing between renderer processes.
-// It maintains a list of processes that are listening to events and a set of
-// open channels.
-//
-// Messaging works this way:
-// - An extension-owned script context (like a background page or a content
-//   script) adds an event listener to the "onConnect" event.
-// - Another context calls "extension.connect()" to open a channel to the
-// extension process, or an extension context calls "tabs.connect(tabId)" to
-// open a channel to the content scripts for the given tab.  The EMS notifies
-// the target process/tab, which then calls the onConnect event in every
-// context owned by the connecting extension in that process/tab.
-// - Once the channel is established, either side can call postMessage to send
-// a message to the opposite side of the channel, which may have multiple
-// listeners.
-//
-// Terminology:
-// channel: connection between two ports
-// port: an IPC::Message::Process interface and an optional routing_id (in the
-// case that the port is a tab).  The Process is usually either a
-// RenderProcessHost or a RenderViewHost.
-class ExtensionMessageService : public content::NotificationObserver {
- public:
-  // A messaging channel. Note that the opening port can be the same as the
-  // receiver, if an extension background page wants to talk to its tab (for
-  // example).
-  struct MessageChannel;
-  struct MessagePort;
-
-  // Allocates a pair of port ids.
-  // NOTE: this can be called from any thread.
-  static void AllocatePortIdPair(int* port1, int* port2);
-
-  explicit ExtensionMessageService(extensions::LazyBackgroundTaskQueue* queue);
-  virtual ~ExtensionMessageService();
-
-  // Given an extension's ID, opens a channel between the given renderer "port"
-  // and every listening context owned by that extension. |channel_name| is
-  // an optional identifier for use by extension developers.
-  void OpenChannelToExtension(
-      int source_process_id, int source_routing_id, int receiver_port_id,
-      const std::string& source_extension_id,
-      const std::string& target_extension_id,
-      const std::string& channel_name);
-
-  // Same as above, but opens a channel to the tab with the given ID.  Messages
-  // are restricted to that tab, so if there are multiple tabs in that process,
-  // only the targeted tab will receive messages.
-  void OpenChannelToTab(
-      int source_process_id, int source_routing_id, int receiver_port_id,
-      int tab_id, const std::string& extension_id,
-      const std::string& channel_name);
-
-  // Closes the message channel associated with the given port, and notifies
-  // the other side.
-  void CloseChannel(int port_id, bool connection_error);
-
-  // Sends a message from a renderer to the given port.
-  void PostMessageFromRenderer(int port_id, const std::string& message);
-
- private:
-  friend class MockExtensionMessageService;
-  struct OpenChannelParams;
-
-  // A map of channel ID to its channel object.
-  typedef std::map<int, MessageChannel*> MessageChannelMap;
-
-  // A map of channel ID to information about the extension that is waiting
-  // for that channel to open. Used for lazy background pages.
-  typedef std::string ExtensionID;
-  typedef std::pair<Profile*, ExtensionID> PendingChannel;
-  typedef std::map<int, PendingChannel> PendingChannelMap;
-
-  // Common among OpenChannel* variants.
-  bool OpenChannelImpl(const OpenChannelParams& params);
-
-  void CloseChannelImpl(MessageChannelMap::iterator channel_iter,
-                        int port_id, bool connection_error,
-                        bool notify_other_port);
-
-  // content::NotificationObserver interface.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
-  // A process that might be in our list of channels has closed.
-  void OnProcessClosed(content::RenderProcessHost* process);
-
-  // Potentially registers a pending task with the LazyBackgroundTaskQueue
-  // to open a channel. Returns true if a task was queued.
-  bool MaybeAddPendingOpenChannelTask(Profile* profile,
-                                      const OpenChannelParams& params);
-
-  // Callbacks for LazyBackgroundTaskQueue tasks. The queue passes in an
-  // ExtensionHost to its task callbacks, though some of our callbacks don't
-  // use that argument.
-  void PendingOpenChannel(const OpenChannelParams& params,
-                          int source_process_id,
-                          ExtensionHost* host);
-  void PendingCloseChannel(int port_id,
-                           bool connection_error,
-                           ExtensionHost* host) {
-    if (host)
-      CloseChannel(port_id, connection_error);
-  }
-  void PendingPostMessage(int port_id,
-                          const std::string& message,
-                          ExtensionHost* host) {
-    if (host)
-      PostMessageFromRenderer(port_id, message);
-  }
-
-  content::NotificationRegistrar registrar_;
-  MessageChannelMap channels_;
-  PendingChannelMap pending_channels_;
-
-  // Weak pointer. Guaranteed to outlive this class.
-  extensions::LazyBackgroundTaskQueue* lazy_background_task_queue_;
-
-  DISALLOW_COPY_AND_ASSIGN(ExtensionMessageService);
-};
-
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_MESSAGE_SERVICE_H_