components/keyed_service/ios/browser_state_dependency_manager.h

   1 // Copyright 2014 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 COMPONENTS_KEYED_SERVICE_IOS_BROWSER_STATE_DEPENDENCY_MANAGER_H_
   6 #define COMPONENTS_KEYED_SERVICE_IOS_BROWSER_STATE_DEPENDENCY_MANAGER_H_
   7
   8 #include "base/callback_forward.h"
   9 #include "base/callback_list.h"
  10 #include "base/macros.h"
  11 #include "components/keyed_service/core/dependency_manager.h"
  12 #include "components/keyed_service/core/keyed_service_export.h"
  13
  14 namespace base {
  15 template <typename T>
  16 struct DefaultSingletonTraits;
  17 }  // namespace base
  18
  19 namespace web {
  20 class BrowserState;
  21 }
  22
  23 namespace user_prefs {
  24 class PrefRegistrySyncable;
  25 }
  26
  27 // A singleton that listens for context destruction notifications and
  28 // rebroadcasts them to each KeyedServiceBaseFactory in a safe order
  29 // based on the stated dependencies by each service.
  30 class KEYED_SERVICE_EXPORT BrowserStateDependencyManager
  31     : public DependencyManager {
  32  public:
  33   static BrowserStateDependencyManager* GetInstance();
  34
  35   // Registers context-specific preferences for all services via |registry|.
  36   // |context| should be the BrowserState containing |registry| and is used as
  37   // a key to prevent multiple registrations on the same BrowserState in
  38   // tests.
  39   void RegisterBrowserStatePrefsForServices(
  40       web::BrowserState* context,
  41       user_prefs::PrefRegistrySyncable* registry);
  42
  43   // Called by each BrowserState to alert us of its creation. Service that
  44   // want to be started when BrowserState is created should override the
  45   // ServiceIsCreatedWithBrowserState() method in their factory. Preferences
  46   // registration also happens during that method call.
  47   void CreateBrowserStateServices(web::BrowserState* context);
  48
  49   // Similar to CreateBrowserStateServices(), except this is used for creating
  50   // test BrowserStates - these contexts will not create services for any
  51   // BrowserStateKeyedBaseFactories that return true from
  52   // ServiceIsNULLWhileTesting().
  53   void CreateBrowserStateServicesForTest(web::BrowserState* context);
  54
  55   // Called by each BrowserState to alert us that we should destroy services
  56   // associated with it.
  57   void DestroyBrowserStateServices(web::BrowserState* context);
  58
  59 #ifndef NDEBUG
  60   // Debugging assertion called as part of GetServiceForBrowserState in debug
  61   // mode. This will NOTREACHED() whenever the user is trying to access a stale
  62   // BrowserState*.
  63   void AssertBrowserStateWasntDestroyed(web::BrowserState* context);
  64
  65   // Marks |context| as live (i.e., not stale). This method can be called as a
  66   // safeguard against |AssertBrowserStateWasntDestroyed()| checks going off
  67   // due to |context| aliasing a BrowserState instance from a prior test
  68   // (i.e., 0xWhatever might be created, be destroyed, and then a new
  69   // BrowserState object might be created at 0xWhatever).
  70   void MarkBrowserStateLiveForTesting(web::BrowserState* context);
  71 #endif  // NDEBUG
  72
  73  private:
  74   friend struct base::DefaultSingletonTraits<BrowserStateDependencyManager>;
  75
  76   BrowserStateDependencyManager();
  77   ~BrowserStateDependencyManager() override;
  78
  79   // Helper function used by CreateBrowserStateServices[ForTest].
  80   void DoCreateBrowserStateServices(web::BrowserState* context,
  81                                     bool is_testing_context);
  82
  83 #ifndef NDEBUG
  84   // DependencyManager:
  85   void DumpContextDependencies(base::SupportsUserData* context) const final;
  86 #endif  // NDEBUG
  87
  88   DISALLOW_COPY_AND_ASSIGN(BrowserStateDependencyManager);
  89 };
  90
  91 #endif  // COMPONENTS_KEYED_SERVICE_IOS_BROWSER_STATE_DEPENDENCY_MANAGER_H_