device/usb/usb_service.cc

   1 // Copyright 2015 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 #include "device/usb/usb_service.h"
   6
   7 #include "base/message_loop/message_loop.h"
   8 #include "components/device_event_log/device_event_log.h"
   9 #include "device/usb/usb_device.h"
  10 #include "device/usb/usb_service_impl.h"
  11
  12 namespace device {
  13
  14 namespace {
  15
  16 UsbService* g_service;
  17
  18 }  // namespace
  19
  20 void UsbService::Observer::OnDeviceAdded(scoped_refptr<UsbDevice> device) {
  21 }
  22
  23 void UsbService::Observer::OnDeviceRemoved(scoped_refptr<UsbDevice> device) {
  24 }
  25
  26 void UsbService::Observer::OnDeviceRemovedCleanup(
  27     scoped_refptr<UsbDevice> device) {
  28 }
  29
  30 // static
  31 UsbService* UsbService::GetInstance(
  32     scoped_refptr<base::SequencedTaskRunner> blocking_task_runner) {
  33   if (!g_service) {
  34     // UsbService constructor saves the pointer this returns and UsbServiceImpl
  35     // will destroy itself when the current message loop exits.
  36     UsbServiceImpl::Create(blocking_task_runner);
  37   }
  38   return g_service;
  39 }
  40
  41 UsbService::UsbService() {
  42   DCHECK(!g_service);
  43   g_service = this;
  44 }
  45
  46 UsbService::~UsbService() {
  47   DCHECK(g_service);
  48   g_service = nullptr;
  49 }
  50
  51 void UsbService::AddObserver(Observer* observer) {
  52   DCHECK(CalledOnValidThread());
  53   observer_list_.AddObserver(observer);
  54 }
  55
  56 void UsbService::RemoveObserver(Observer* observer) {
  57   DCHECK(CalledOnValidThread());
  58   observer_list_.RemoveObserver(observer);
  59 }
  60
  61 void UsbService::NotifyDeviceAdded(scoped_refptr<UsbDevice> device) {
  62   DCHECK(CalledOnValidThread());
  63
  64   FOR_EACH_OBSERVER(Observer, observer_list_, OnDeviceAdded(device));
  65 }
  66
  67 void UsbService::NotifyDeviceRemoved(scoped_refptr<UsbDevice> device) {
  68   DCHECK(CalledOnValidThread());
  69
  70   FOR_EACH_OBSERVER(Observer, observer_list_, OnDeviceRemoved(device));
  71   FOR_EACH_OBSERVER(Observer, observer_list_, OnDeviceRemovedCleanup(device));
  72 }
  73
  74 }  // namespace device