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