1 // Copyright (c) 2012 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.
5 #include "content/browser/device_monitor_mac.h"
7 #import <QTKit/QTKit.h>
11 #include "base/bind_helpers.h"
12 #include "base/logging.h"
13 #include "base/mac/bind_objc_block.h"
14 #include "base/mac/scoped_nsobject.h"
15 #include "base/threading/thread_checker.h"
16 #include "content/public/browser/browser_thread.h"
17 #import "media/base/mac/avfoundation_glue.h"
19 using content::BrowserThread;
23 // This class is used to keep track of system devices names and their types.
34 DeviceInfo(std::string unique_id, DeviceType type)
35 : unique_id_(unique_id), type_(type) {}
37 // Operator== is needed here to use this class in a std::find. A given
38 // |unique_id_| always has the same |type_| so for comparison purposes the
39 // latter can be safely ignored.
40 bool operator==(const DeviceInfo& device) const {
41 return unique_id_ == device.unique_id_;
44 const std::string& unique_id() const { return unique_id_; }
45 DeviceType type() const { return type_; }
48 std::string unique_id_;
50 // Allow generated copy constructor and assignment.
53 // Base abstract class used by DeviceMonitorMac to interact with either a QTKit
54 // or an AVFoundation implementation of events and notifications.
55 class DeviceMonitorMacImpl {
57 explicit DeviceMonitorMacImpl(content::DeviceMonitorMac* monitor)
61 device_removal_(nil) {
63 // Initialise the devices_cache_ with a not-valid entry. For the case in
64 // which there is one single device in the system and we get notified when
65 // it gets removed, this will prevent the system from thinking that no
66 // devices were added nor removed and not notifying the |monitor_|.
67 cached_devices_.push_back(DeviceInfo("invalid", DeviceInfo::kInvalid));
69 virtual ~DeviceMonitorMacImpl() {}
71 virtual void OnDeviceChanged() = 0;
73 // Method called by the default notification center when a device is removed
74 // or added to the system. It will compare the |cached_devices_| with the
75 // current situation, update it, and, if there's an update, signal to
76 // |monitor_| with the appropriate device type.
77 void ConsolidateDevicesListAndNotify(
78 const std::vector<DeviceInfo>& snapshot_devices);
81 content::DeviceMonitorMac* monitor_;
82 std::vector<DeviceInfo> cached_devices_;
84 // Handles to NSNotificationCenter block observers.
89 DISALLOW_COPY_AND_ASSIGN(DeviceMonitorMacImpl);
92 void DeviceMonitorMacImpl::ConsolidateDevicesListAndNotify(
93 const std::vector<DeviceInfo>& snapshot_devices) {
94 bool video_device_added = false;
95 bool audio_device_added = false;
96 bool video_device_removed = false;
97 bool audio_device_removed = false;
99 // Compare the current system devices snapshot with the ones cached to detect
100 // additions, present in the former but not in the latter. If we find a device
101 // in snapshot_devices entry also present in cached_devices, we remove it from
102 // the latter vector.
103 std::vector<DeviceInfo>::const_iterator it;
104 for (it = snapshot_devices.begin(); it != snapshot_devices.end(); ++it) {
105 std::vector<DeviceInfo>::iterator cached_devices_iterator =
106 std::find(cached_devices_.begin(), cached_devices_.end(), *it);
107 if (cached_devices_iterator == cached_devices_.end()) {
108 video_device_added |= ((it->type() == DeviceInfo::kVideo) ||
109 (it->type() == DeviceInfo::kMuxed));
110 audio_device_added |= ((it->type() == DeviceInfo::kAudio) ||
111 (it->type() == DeviceInfo::kMuxed));
112 DVLOG(1) << "Device has been added, id: " << it->unique_id();
114 cached_devices_.erase(cached_devices_iterator);
117 // All the remaining entries in cached_devices are removed devices.
118 for (it = cached_devices_.begin(); it != cached_devices_.end(); ++it) {
119 video_device_removed |= ((it->type() == DeviceInfo::kVideo) ||
120 (it->type() == DeviceInfo::kMuxed) ||
121 (it->type() == DeviceInfo::kInvalid));
122 audio_device_removed |= ((it->type() == DeviceInfo::kAudio) ||
123 (it->type() == DeviceInfo::kMuxed) ||
124 (it->type() == DeviceInfo::kInvalid));
125 DVLOG(1) << "Device has been removed, id: " << it->unique_id();
127 // Update the cached devices with the current system snapshot.
128 cached_devices_ = snapshot_devices;
130 if (video_device_added || video_device_removed)
131 monitor_->NotifyDeviceChanged(base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE);
132 if (audio_device_added || audio_device_removed)
133 monitor_->NotifyDeviceChanged(base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
136 class QTKitMonitorImpl : public DeviceMonitorMacImpl {
138 explicit QTKitMonitorImpl(content::DeviceMonitorMac* monitor);
139 ~QTKitMonitorImpl() override;
141 void OnDeviceChanged() override;
145 void OnAttributeChanged(NSNotification* notification);
150 QTKitMonitorImpl::QTKitMonitorImpl(content::DeviceMonitorMac* monitor)
151 : DeviceMonitorMacImpl(monitor) {
152 NSNotificationCenter* nc = [NSNotificationCenter defaultCenter];
154 [nc addObserverForName:QTCaptureDeviceWasConnectedNotification
157 usingBlock:^(NSNotification* notification) {
158 OnDeviceChanged();}];
160 [nc addObserverForName:QTCaptureDeviceWasDisconnectedNotification
163 usingBlock:^(NSNotification* notification) {
164 OnDeviceChanged();}];
166 [nc addObserverForName:QTCaptureDeviceAttributeDidChangeNotification
169 usingBlock:^(NSNotification* notification) {
170 OnAttributeChanged(notification);}];
173 QTKitMonitorImpl::~QTKitMonitorImpl() {
174 NSNotificationCenter* nc = [NSNotificationCenter defaultCenter];
175 [nc removeObserver:device_arrival_];
176 [nc removeObserver:device_removal_];
177 [nc removeObserver:device_change_];
180 void QTKitMonitorImpl::OnAttributeChanged(
181 NSNotification* notification) {
182 if ([[[notification userInfo]
183 objectForKey:QTCaptureDeviceChangedAttributeKey]
184 isEqualToString:QTCaptureDeviceSuspendedAttribute]) {
189 void QTKitMonitorImpl::OnDeviceChanged() {
190 std::vector<DeviceInfo> snapshot_devices;
192 NSArray* devices = [QTCaptureDevice inputDevices];
193 for (QTCaptureDevice* device in devices) {
194 DeviceInfo::DeviceType device_type = DeviceInfo::kUnknown;
195 // Act as if suspended video capture devices are not attached. For
196 // example, a laptop's internal webcam is suspended when the lid is closed.
197 if ([device hasMediaType:QTMediaTypeVideo] &&
198 ![[device attributeForKey:QTCaptureDeviceSuspendedAttribute]
200 device_type = DeviceInfo::kVideo;
201 } else if ([device hasMediaType:QTMediaTypeMuxed] &&
202 ![[device attributeForKey:QTCaptureDeviceSuspendedAttribute]
204 device_type = DeviceInfo::kMuxed;
205 } else if ([device hasMediaType:QTMediaTypeSound] &&
206 ![[device attributeForKey:QTCaptureDeviceSuspendedAttribute]
208 device_type = DeviceInfo::kAudio;
210 snapshot_devices.push_back(
211 DeviceInfo([[device uniqueID] UTF8String], device_type));
213 ConsolidateDevicesListAndNotify(snapshot_devices);
216 // Forward declaration for use by CrAVFoundationDeviceObserver.
217 class SuspendObserverDelegate;
221 // This class is a Key-Value Observer (KVO) shim. It is needed because C++
222 // classes cannot observe Key-Values directly. Created, manipulated, and
223 // destroyed on the UI Thread by SuspendObserverDelegate.
224 @interface CrAVFoundationDeviceObserver : NSObject {
226 // Callback for device changed, has to run on Device Thread.
227 base::Closure onDeviceChangedCallback_;
229 // Member to keep track of the devices we are already monitoring.
230 std::set<base::scoped_nsobject<CrAVCaptureDevice> > monitoredDevices_;
233 - (id)initWithOnChangedCallback:(const base::Closure&)callback;
234 - (void)startObserving:(base::scoped_nsobject<CrAVCaptureDevice>)device;
235 - (void)stopObserving:(CrAVCaptureDevice*)device;
236 - (void)clearOnDeviceChangedCallback;
242 // This class owns and manages the lifetime of a CrAVFoundationDeviceObserver.
243 // It is created and destroyed in UI thread by AVFoundationMonitorImpl, and it
244 // operates on this thread except for the expensive device enumerations which
245 // are run on Device Thread.
246 class SuspendObserverDelegate :
247 public base::RefCountedThreadSafe<SuspendObserverDelegate> {
249 explicit SuspendObserverDelegate(DeviceMonitorMacImpl* monitor);
251 // Create |suspend_observer_| for all devices and register OnDeviceChanged()
252 // as its change callback. Schedule bottom half in DoStartObserver().
254 const scoped_refptr<base::SingleThreadTaskRunner>& device_thread);
255 // Enumerate devices in |device_thread| and run the bottom half in
256 // DoOnDeviceChange(). |suspend_observer_| calls back here on suspend event,
257 // and our parent AVFoundationMonitorImpl calls on connect/disconnect device.
258 void OnDeviceChanged(
259 const scoped_refptr<base::SingleThreadTaskRunner>& device_thread);
260 // Remove the device monitor's weak reference. Remove ourselves as suspend
261 // notification observer from |suspend_observer_|.
262 void ResetDeviceMonitor();
265 friend class base::RefCountedThreadSafe<SuspendObserverDelegate>;
267 virtual ~SuspendObserverDelegate();
269 // Bottom half of StartObserver(), starts |suspend_observer_| for all devices.
270 // Assumes that |devices| has been retained prior to being called, and
271 // releases it internally.
272 void DoStartObserver(NSArray* devices);
273 // Bottom half of OnDeviceChanged(), starts |suspend_observer_| for current
274 // devices and composes a snapshot of them to send it to
275 // |avfoundation_monitor_impl_|. Assumes that |devices| has been retained
276 // prior to being called, and releases it internally.
277 void DoOnDeviceChanged(NSArray* devices);
279 base::scoped_nsobject<CrAVFoundationDeviceObserver> suspend_observer_;
280 DeviceMonitorMacImpl* avfoundation_monitor_impl_;
283 SuspendObserverDelegate::SuspendObserverDelegate(DeviceMonitorMacImpl* monitor)
284 : avfoundation_monitor_impl_(monitor) {
285 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
288 void SuspendObserverDelegate::StartObserver(
289 const scoped_refptr<base::SingleThreadTaskRunner>& device_thread) {
290 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
292 base::Closure on_device_changed_callback =
293 base::Bind(&SuspendObserverDelegate::OnDeviceChanged,
294 this, device_thread);
295 suspend_observer_.reset([[CrAVFoundationDeviceObserver alloc]
296 initWithOnChangedCallback:on_device_changed_callback]);
298 // Enumerate the devices in Device thread and post the observers start to be
299 // done on UI thread. The devices array is retained in |device_thread| and
300 // released in DoStartObserver().
301 base::PostTaskAndReplyWithResult(
304 base::BindBlock(^{ return [[AVCaptureDeviceGlue devices] retain]; }),
305 base::Bind(&SuspendObserverDelegate::DoStartObserver, this));
308 void SuspendObserverDelegate::OnDeviceChanged(
309 const scoped_refptr<base::SingleThreadTaskRunner>& device_thread) {
310 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
311 // Enumerate the devices in Device thread and post the consolidation of the
312 // new devices and the old ones to be done on UI thread. The devices array
313 // is retained in |device_thread| and released in DoOnDeviceChanged().
314 PostTaskAndReplyWithResult(
317 base::BindBlock(^{ return [[AVCaptureDeviceGlue devices] retain]; }),
318 base::Bind(&SuspendObserverDelegate::DoOnDeviceChanged, this));
321 void SuspendObserverDelegate::ResetDeviceMonitor() {
322 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
323 avfoundation_monitor_impl_ = NULL;
324 [suspend_observer_ clearOnDeviceChangedCallback];
327 SuspendObserverDelegate::~SuspendObserverDelegate() {
328 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
331 void SuspendObserverDelegate::DoStartObserver(NSArray* devices) {
332 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
333 base::scoped_nsobject<NSArray> auto_release(devices);
334 for (CrAVCaptureDevice* device in devices) {
335 base::scoped_nsobject<CrAVCaptureDevice> device_ptr([device retain]);
336 [suspend_observer_ startObserving:device_ptr];
340 void SuspendObserverDelegate::DoOnDeviceChanged(NSArray* devices) {
341 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
342 base::scoped_nsobject<NSArray> auto_release(devices);
343 std::vector<DeviceInfo> snapshot_devices;
344 for (CrAVCaptureDevice* device in devices) {
345 base::scoped_nsobject<CrAVCaptureDevice> device_ptr([device retain]);
346 [suspend_observer_ startObserving:device_ptr];
348 BOOL suspended = [device respondsToSelector:@selector(isSuspended)] &&
349 [device isSuspended];
350 DeviceInfo::DeviceType device_type = DeviceInfo::kUnknown;
351 if ([device hasMediaType:AVFoundationGlue::AVMediaTypeVideo()]) {
354 device_type = DeviceInfo::kVideo;
355 } else if ([device hasMediaType:AVFoundationGlue::AVMediaTypeMuxed()]) {
356 device_type = suspended ? DeviceInfo::kAudio : DeviceInfo::kMuxed;
357 } else if ([device hasMediaType:AVFoundationGlue::AVMediaTypeAudio()]) {
358 device_type = DeviceInfo::kAudio;
360 snapshot_devices.push_back(DeviceInfo([[device uniqueID] UTF8String],
363 // Make sure no references are held to |devices| when
364 // ConsolidateDevicesListAndNotify is called since the VideoCaptureManager
365 // and AudioCaptureManagers also enumerates the available devices but on
367 auto_release.reset();
368 // |avfoundation_monitor_impl_| might have been NULLed asynchronously before
369 // arriving at this line.
370 if (avfoundation_monitor_impl_) {
371 avfoundation_monitor_impl_->ConsolidateDevicesListAndNotify(
376 // AVFoundation implementation of the Mac Device Monitor, registers as a global
377 // device connect/disconnect observer and plugs suspend/wake up device observers
378 // per device. This class is created and lives in UI thread. Owns a
379 // SuspendObserverDelegate that notifies when a device is suspended/resumed.
380 class AVFoundationMonitorImpl : public DeviceMonitorMacImpl {
382 AVFoundationMonitorImpl(
383 content::DeviceMonitorMac* monitor,
384 const scoped_refptr<base::SingleThreadTaskRunner>& device_task_runner);
385 ~AVFoundationMonitorImpl() override;
387 void OnDeviceChanged() override;
390 // {Video,AudioInput}DeviceManager's "Device" thread task runner used for
391 // posting tasks to |suspend_observer_delegate_|; valid after
392 // MediaStreamManager calls StartMonitoring().
393 const scoped_refptr<base::SingleThreadTaskRunner> device_task_runner_;
395 scoped_refptr<SuspendObserverDelegate> suspend_observer_delegate_;
397 DISALLOW_COPY_AND_ASSIGN(AVFoundationMonitorImpl);
400 AVFoundationMonitorImpl::AVFoundationMonitorImpl(
401 content::DeviceMonitorMac* monitor,
402 const scoped_refptr<base::SingleThreadTaskRunner>& device_task_runner)
403 : DeviceMonitorMacImpl(monitor),
404 device_task_runner_(device_task_runner),
405 suspend_observer_delegate_(new SuspendObserverDelegate(this)) {
406 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
407 NSNotificationCenter* nc = [NSNotificationCenter defaultCenter];
409 [nc addObserverForName:AVFoundationGlue::
410 AVCaptureDeviceWasConnectedNotification()
413 usingBlock:^(NSNotification* notification) {
414 OnDeviceChanged();}];
416 [nc addObserverForName:AVFoundationGlue::
417 AVCaptureDeviceWasDisconnectedNotification()
420 usingBlock:^(NSNotification* notification) {
421 OnDeviceChanged();}];
422 suspend_observer_delegate_->StartObserver(device_task_runner_);
425 AVFoundationMonitorImpl::~AVFoundationMonitorImpl() {
426 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
427 suspend_observer_delegate_->ResetDeviceMonitor();
428 NSNotificationCenter* nc = [NSNotificationCenter defaultCenter];
429 [nc removeObserver:device_arrival_];
430 [nc removeObserver:device_removal_];
433 void AVFoundationMonitorImpl::OnDeviceChanged() {
434 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
435 suspend_observer_delegate_->OnDeviceChanged(device_task_runner_);
440 @implementation CrAVFoundationDeviceObserver
442 - (id)initWithOnChangedCallback:(const base::Closure&)callback {
443 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
444 if ((self = [super init])) {
445 DCHECK(!callback.is_null());
446 onDeviceChangedCallback_ = callback;
452 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
453 std::set<base::scoped_nsobject<CrAVCaptureDevice> >::iterator it =
454 monitoredDevices_.begin();
455 while (it != monitoredDevices_.end())
456 [self removeObservers:*(it++)];
460 - (void)startObserving:(base::scoped_nsobject<CrAVCaptureDevice>)device {
461 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
462 DCHECK(device != nil);
463 // Skip this device if there are already observers connected to it.
464 if (std::find(monitoredDevices_.begin(), monitoredDevices_.end(), device) !=
465 monitoredDevices_.end()) {
468 [device addObserver:self
469 forKeyPath:@"suspended"
471 context:device.get()];
472 [device addObserver:self
473 forKeyPath:@"connected"
475 context:device.get()];
476 monitoredDevices_.insert(device);
479 - (void)stopObserving:(CrAVCaptureDevice*)device {
480 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
481 DCHECK(device != nil);
483 std::set<base::scoped_nsobject<CrAVCaptureDevice> >::iterator found =
484 std::find(monitoredDevices_.begin(), monitoredDevices_.end(), device);
485 DCHECK(found != monitoredDevices_.end());
486 [self removeObservers:*found];
487 monitoredDevices_.erase(found);
490 - (void)clearOnDeviceChangedCallback {
491 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
492 onDeviceChangedCallback_.Reset();
495 - (void)removeObservers:(CrAVCaptureDevice*)device {
496 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
497 // Check sanity of |device| via its -observationInfo. http://crbug.com/371271.
498 if ([device observationInfo]) {
499 [device removeObserver:self
500 forKeyPath:@"suspended"];
501 [device removeObserver:self
502 forKeyPath:@"connected"];
506 - (void)observeValueForKeyPath:(NSString*)keyPath
508 change:(NSDictionary*)change
509 context:(void*)context {
510 DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
511 if ([keyPath isEqual:@"suspended"])
512 onDeviceChangedCallback_.Run();
513 if ([keyPath isEqual:@"connected"])
514 [self stopObserving:static_cast<CrAVCaptureDevice*>(context)];
517 @end // @implementation CrAVFoundationDeviceObserver
521 DeviceMonitorMac::DeviceMonitorMac() {
522 // Both QTKit and AVFoundation do not need to be fired up until the user
523 // exercises a GetUserMedia. Bringing up either library and enumerating the
524 // devices in the system is an operation taking in the range of hundred of ms,
525 // so it is triggered explicitly from MediaStreamManager::StartMonitoring().
528 DeviceMonitorMac::~DeviceMonitorMac() {}
530 void DeviceMonitorMac::StartMonitoring(
531 const scoped_refptr<base::SingleThreadTaskRunner>& device_task_runner) {
532 DCHECK(thread_checker_.CalledOnValidThread());
533 if (AVFoundationGlue::IsAVFoundationSupported()) {
534 DVLOG(1) << "Monitoring via AVFoundation";
535 device_monitor_impl_.reset(new AVFoundationMonitorImpl(this,
536 device_task_runner));
538 DVLOG(1) << "Monitoring via QTKit";
539 device_monitor_impl_.reset(new QTKitMonitorImpl(this));
543 void DeviceMonitorMac::NotifyDeviceChanged(
544 base::SystemMonitor::DeviceType type) {
545 DCHECK(thread_checker_.CalledOnValidThread());
546 // TODO(xians): Remove the global variable for SystemMonitor.
547 base::SystemMonitor::Get()->ProcessDevicesChanged(type);
550 } // namespace content