extensions/browser/api/hid/hid_device_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 EXTENSIONS_BROWSER_API_HID_HID_DEVICE_MANAGER_H_
   6 #define EXTENSIONS_BROWSER_API_HID_HID_DEVICE_MANAGER_H_
   7
   8 #include <map>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13 #include "base/memory/scoped_vector.h"
  14 #include "base/scoped_observer.h"
  15 #include "base/threading/thread_checker.h"
  16 #include "device/hid/hid_device_info.h"
  17 #include "device/hid/hid_service.h"
  18 #include "extensions/browser/browser_context_keyed_api_factory.h"
  19 #include "extensions/browser/event_router.h"
  20 #include "extensions/common/api/hid.h"
  21
  22 namespace device {
  23 class HidDeviceFilter;
  24 }
  25
  26 namespace extensions {
  27
  28 class Extension;
  29
  30 // This service maps devices enumerated by device::HidService to resource IDs
  31 // returned by the chrome.hid API.
  32 class HidDeviceManager : public BrowserContextKeyedAPI,
  33                          public device::HidService::Observer,
  34                          public EventRouter::Observer {
  35  public:
  36   typedef base::Callback<void(scoped_ptr<base::ListValue>)>
  37       GetApiDevicesCallback;
  38
  39   explicit HidDeviceManager(content::BrowserContext* context);
  40   ~HidDeviceManager() override;
  41
  42   // BrowserContextKeyedAPI implementation.
  43   static BrowserContextKeyedAPIFactory<HidDeviceManager>* GetFactoryInstance();
  44
  45   // Convenience method to get the HidDeviceManager for a profile.
  46   static HidDeviceManager* Get(content::BrowserContext* context) {
  47     return BrowserContextKeyedAPIFactory<HidDeviceManager>::Get(context);
  48   }
  49
  50   // Enumerates available devices, taking into account the permissions held by
  51   // the given extension and the filters provided. The provided callback will
  52   // be posted to the calling thread's task runner with a list of device info
  53   // objects.
  54   void GetApiDevices(const Extension* extension,
  55                      const std::vector<device::HidDeviceFilter>& filters,
  56                      const GetApiDevicesCallback& callback);
  57
  58   scoped_refptr<device::HidDeviceInfo> GetDeviceInfo(int resource_id);
  59
  60   static bool HasPermission(const Extension* extension,
  61                             scoped_refptr<device::HidDeviceInfo> device_info);
  62
  63  private:
  64   friend class BrowserContextKeyedAPIFactory<HidDeviceManager>;
  65
  66   typedef std::map<int, device::HidDeviceId> ResourceIdToDeviceIdMap;
  67   typedef std::map<device::HidDeviceId, int> DeviceIdToResourceIdMap;
  68
  69   struct GetApiDevicesParams;
  70
  71   // KeyedService:
  72   void Shutdown() override;
  73
  74   // BrowserContextKeyedAPI:
  75   static const char* service_name() { return "HidDeviceManager"; }
  76   static const bool kServiceHasOwnInstanceInIncognito = true;
  77   static const bool kServiceIsNULLWhileTesting = true;
  78
  79   // EventRouter::Observer:
  80   void OnListenerAdded(const EventListenerInfo& details) override;
  81
  82   // HidService::Observer:
  83   void OnDeviceAdded(scoped_refptr<device::HidDeviceInfo> device_info) override;
  84   void OnDeviceRemoved(
  85       scoped_refptr<device::HidDeviceInfo> device_info) override;
  86
  87   // Wait to perform an initial enumeration and register a HidService::Observer
  88   // until the first API customer makes a request or registers an event
  89   // listener.
  90   void LazyInitialize();
  91
  92   // Builds a list of device info objects representing the currently enumerated
  93   // devices, taking into account the permissions held by the given extension
  94   // and the filters provided.
  95   scoped_ptr<base::ListValue> CreateApiDeviceList(
  96       const Extension* extension,
  97       const std::vector<device::HidDeviceFilter>& filters);
  98   void OnEnumerationComplete(
  99       const std::vector<scoped_refptr<device::HidDeviceInfo>>& devices);
 100
 101   void DispatchEvent(const std::string& event_name,
 102                      scoped_ptr<base::ListValue> event_args,
 103                      scoped_refptr<device::HidDeviceInfo> device_info);
 104
 105   base::ThreadChecker thread_checker_;
 106   EventRouter* event_router_;
 107   bool initialized_;
 108   ScopedObserver<device::HidService, device::HidService::Observer>
 109       hid_service_observer_;
 110   bool enumeration_ready_;
 111   ScopedVector<GetApiDevicesParams> pending_enumerations_;
 112   int next_resource_id_;
 113   ResourceIdToDeviceIdMap device_ids_;
 114   DeviceIdToResourceIdMap resource_ids_;
 115   base::WeakPtrFactory<HidDeviceManager> weak_factory_;
 116
 117   DISALLOW_COPY_AND_ASSIGN(HidDeviceManager);
 118 };
 119
 120 }  // namespace extensions
 121
 122 #endif  // EXTENSIONS_BROWSER_API_HID_HID_DEVICE_MANAGER_H_