chrome/browser/chromeos/system/automatic_reboot_manager.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROME_BROWSER_CHROMEOS_SYSTEM_AUTOMATIC_REBOOT_MANAGER_H_
   6 #define CHROME_BROWSER_CHROMEOS_SYSTEM_AUTOMATIC_REBOOT_MANAGER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "base/compiler_specific.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "base/memory/weak_ptr.h"
  12 #include "base/observer_list.h"
  13 #include "base/prefs/pref_change_registrar.h"
  14 #include "base/time/time.h"
  15 #include "base/timer/timer.h"
  16 #include "chromeos/dbus/power_manager_client.h"
  17 #include "chromeos/dbus/update_engine_client.h"
  18 #include "content/public/browser/notification_observer.h"
  19 #include "content/public/browser/notification_registrar.h"
  20 #include "ui/wm/core/user_activity_observer.h"
  21
  22 class PrefRegistrySimple;
  23
  24 namespace base {
  25 class TickClock;
  26 }
  27
  28 namespace chromeos {
  29 namespace system {
  30
  31 class AutomaticRebootManagerObserver;
  32
  33 // Schedules and executes automatic reboots.
  34 //
  35 // Automatic reboots may be scheduled for any number of reasons. Currently, the
  36 // following are implemented:
  37 // * When Chrome OS has applied a system update, a reboot may become necessary
  38 //   to complete the update process. If the policy to automatically reboot after
  39 //   an update is enabled, a reboot is scheduled at that point.
  40 // * If an uptime limit is set through policy, a reboot is scheduled when the
  41 //   device's uptime reaches the limit. Time spent sleeping counts as uptime as
  42 //   well.
  43 //
  44 // When the time of the earliest scheduled reboot is reached, the reboot is
  45 // requested. The reboot is performed immediately unless one of the following
  46 // reasons inhibits it:
  47 // * If the login screen is being shown: Reboots are inhibited while the user is
  48 //   interacting with the screen (determined by checking whether there has been
  49 //   any user activity in the past 60 seconds).
  50 // * If a session is in progress: Reboots are inhibited until the session ends,
  51 //   the browser is restarted or the device is suspended.
  52 //
  53 // If reboots are inhibited, a 24 hour grace period is started. The reboot
  54 // request is carried out the moment none of the inhibiting criteria apply
  55 // anymore (e.g. the user becomes idle on the login screen, the user logs exits
  56 // a session, the user suspends the device). If reboots remain inhibited for the
  57 // entire grace period, a reboot is unconditionally performed at its end.
  58 //
  59 // Note: Currently, automatic reboots are only enabled while the login screen is
  60 // being shown or a kiosk app session is in progress. This will change in the
  61 // future and the policy will always apply, regardless of whether a session of
  62 // any particular type is in progress or not. http://crbug.com/244972
  63 //
  64 // Reboots may be scheduled and canceled at any time. This causes the time at
  65 // which a reboot should be requested and the grace period that follows it to
  66 // be recalculated.
  67 //
  68 // Reboots are scheduled in terms of device uptime. The current uptime is read
  69 // from /proc/uptime. The time at which a reboot became necessary to finish
  70 // applying an update is stored in /var/run/chrome/update_reboot_needed_uptime,
  71 // making it persist across browser restarts and crashes. Placing the file under
  72 // /var/run ensures that it gets cleared automatically on every boot.
  73 class AutomaticRebootManager : public PowerManagerClient::Observer,
  74                                public UpdateEngineClient::Observer,
  75                                public wm::UserActivityObserver,
  76                                public content::NotificationObserver {
  77  public:
  78   // The current uptime and the uptime at which an update was applied and a
  79   // reboot became necessary (if any). Used to pass this information from the
  80   // blocking thread pool to the UI thread.
  81   struct SystemEventTimes {
  82     SystemEventTimes();
  83     SystemEventTimes(const base::TimeDelta& uptime,
  84                      const base::TimeDelta& update_reboot_needed_uptime);
  85
  86     bool has_boot_time;
  87     base::TimeTicks boot_time;
  88
  89     bool has_update_reboot_needed_time;
  90     base::TimeTicks update_reboot_needed_time;
  91   };
  92
  93   explicit AutomaticRebootManager(scoped_ptr<base::TickClock> clock);
  94   virtual ~AutomaticRebootManager();
  95
  96   void AddObserver(AutomaticRebootManagerObserver* observer);
  97   void RemoveObserver(AutomaticRebootManagerObserver* observer);
  98
  99   // PowerManagerClient::Observer:
 100   virtual void SuspendDone(const base::TimeDelta& sleep_duration) OVERRIDE;
 101
 102   // UpdateEngineClient::Observer:
 103   virtual void UpdateStatusChanged(
 104       const UpdateEngineClient::Status& status) OVERRIDE;
 105
 106   // wm::UserActivityObserver:
 107   virtual void OnUserActivity(const ui::Event* event) OVERRIDE;
 108
 109   // content::NotificationObserver:
 110   virtual void Observe(int type,
 111                        const content::NotificationSource& source,
 112                        const content::NotificationDetails& details) OVERRIDE;
 113
 114   static void RegisterPrefs(PrefRegistrySimple* registry);
 115
 116  private:
 117   friend class AutomaticRebootManagerBasicTest;
 118
 119   // Finishes initialization. Called after the |system_event_times| have been
 120   // loaded in the blocking thread pool.
 121   void Init(const SystemEventTimes& system_event_times);
 122
 123   // Reschedules the reboot request, start and end of the grace period. Reboots
 124   // immediately if the end of the grace period has already passed.
 125   void Reschedule();
 126
 127   // Requests a reboot.
 128   void RequestReboot();
 129
 130   // Called whenever the status of the criteria inhibiting reboots may have
 131   // changed. Reboots immediately if a reboot has actually been requested and
 132   // none of the criteria inhibiting it apply anymore. Otherwise, does nothing.
 133   // If |ignore_session|, a session in progress does not inhibit reboots.
 134   void MaybeReboot(bool ignore_session);
 135
 136   // Reboots immediately.
 137   void Reboot();
 138
 139   // A clock that can be mocked in tests to fast-forward time.
 140   scoped_ptr<base::TickClock> clock_;
 141
 142   PrefChangeRegistrar local_state_registrar_;
 143
 144   content::NotificationRegistrar notification_registrar_;
 145
 146   // Fires when the user has been idle on the login screen for a set amount of
 147   // time.
 148   scoped_ptr<base::OneShotTimer<AutomaticRebootManager> >
 149       login_screen_idle_timer_;
 150
 151   // The time at which the device was booted, in |clock_| ticks.
 152   bool have_boot_time_;
 153   base::TimeTicks boot_time_;
 154
 155   // The time at which an update was applied and a reboot became necessary to
 156   // complete the update process, in |clock_| ticks.
 157   bool have_update_reboot_needed_time_;
 158   base::TimeTicks update_reboot_needed_time_;
 159
 160   // Whether a reboot has been requested.
 161   bool reboot_requested_;
 162
 163   // Timers that start and end the grace period.
 164   scoped_ptr<base::OneShotTimer<AutomaticRebootManager> > grace_start_timer_;
 165   scoped_ptr<base::OneShotTimer<AutomaticRebootManager> > grace_end_timer_;
 166
 167   base::WeakPtrFactory<AutomaticRebootManager> weak_ptr_factory_;
 168
 169   ObserverList<AutomaticRebootManagerObserver, true> observers_;
 170
 171   DISALLOW_COPY_AND_ASSIGN(AutomaticRebootManager);
 172 };
 173
 174 }  // namespace system
 175 }  // namespace chromeos
 176
 177 #endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_AUTOMATIC_REBOOT_MANAGER_H_