Move MachBroker to content.

chrome/browser/mach_broker_mac.h

-// Copyright (c) 2011 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_MACH_BROKER_H_
-#define CHROME_BROWSER_MACH_BROKER_H_
-#pragma once
-
-#include <map>
-#include <string>
-
-#include <mach/mach.h>
-
-#include "base/memory/singleton.h"
-#include "base/process.h"
-#include "base/process_util.h"
-#include "base/synchronization/lock.h"
-#include "content/common/notification_observer.h"
-#include "content/common/notification_registrar.h"
-
-// On OS X, the mach_port_t of a process is required to collect metrics about
-// the process. Running |task_for_pid()| is only allowed for privileged code.
-// However, a process has port rights to all its subprocesses, so let the
-// browser's child processes send their Mach port to the browser over IPC.
-// This way, the brower can at least collect metrics of its child processes,
-// which is what it's most interested in anyway.
-//
-// Mach ports can only be sent over Mach IPC, not over the |socketpair()| that
-// the regular IPC system uses. Hence, the child processes open a Mach
-// connection shortly after launching and ipc their mach data to the browser
-// process. This data is kept in a global |MachBroker| object.
-//
-// Since this data arrives over a separate channel, it is not available
-// immediately after a child process has been started.
-class MachBroker : public base::ProcessMetrics::PortProvider,
-                   public NotificationObserver {
- public:
-  // Returns the global MachBroker.
-  static MachBroker* GetInstance();
-
-  // Performs any necessary setup that cannot happen in the constructor.
-  // Clients MUST call this method before fork()ing any children.
-  void PrepareForFork();
-
-  struct MachInfo {
-    MachInfo() : mach_task_(MACH_PORT_NULL) {}
-
-    MachInfo& SetTask(mach_port_t task) {
-      mach_task_ = task;
-      return *this;
-    }
-
-    mach_port_t mach_task_;
-  };
-
-  // Adds a placeholder to the map for the given pid with MACH_PORT_NULL.
-  // Callers are expected to later update the port with FinalizePid().  Callers
-  // MUST acquire the lock given by GetLock() before calling this method (and
-  // release the lock afterwards).
-  void AddPlaceholderForPid(base::ProcessHandle pid);
-
-  // Updates the mapping for |pid| to include the given |mach_info|.  Does
-  // nothing if PlaceholderForPid() has not already been called for the given
-  // |pid|.  Callers MUST acquire the lock given by GetLock() before calling
-  // this method (and release the lock afterwards).
-  void FinalizePid(base::ProcessHandle pid, const MachInfo& mach_info);
-
-  // Removes all mappings belonging to |pid| from the broker.
-  void InvalidatePid(base::ProcessHandle pid);
-
-  // The lock that protects this MachBroker object.  Clients MUST acquire and
-  // release this lock around calls to PlaceholderForPid() and FinalizePid().
-  base::Lock& GetLock();
-
-  // Returns the Mach port name to use when sending or receiving messages.
-  // Does the Right Thing in the browser and in child processes.
-  static std::string GetMachPortName();
-
-  // Implement |ProcessMetrics::PortProvider|.
-  virtual mach_port_t TaskForPid(base::ProcessHandle process) const;
-
-  // Implement |NotificationObserver|.
-  virtual void Observe(NotificationType type,
-                       const NotificationSource& source,
-                       const NotificationDetails& details);
- private:
-  // Private constructor.
-  MachBroker();
-  virtual ~MachBroker();
-
-  // True if the listener thread has been started.
-  bool listener_thread_started_;
-
-  // Used to register for notifications received by NotificationObserver.
-  // Accessed only on the UI thread.
-  NotificationRegistrar registrar_;
-
-  // Stores mach info for every process in the broker.
-  typedef std::map<base::ProcessHandle, MachInfo> MachMap;
-  MachMap mach_map_;
-
-  // Mutex that guards |mach_map_|.
-  mutable base::Lock lock_;
-
-  friend class MachBrokerTest;
-  friend class RegisterNotificationTask;
-  // Needed in order to make the constructor private.
-  friend struct DefaultSingletonTraits<MachBroker>;
-  DISALLOW_COPY_AND_ASSIGN(MachBroker);
-};
-
-#endif  // CHROME_BROWSER_MACH_BROKER_H_