Fix a M23 stable crash issue for device enumeration on Mac

content/browser/device_monitor_mac.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/device_monitor_mac.h"
 
-#include <IOKit/audio/IOAudioDefines.h>
 #include <IOKit/usb/IOUSBLib.h>
 
 #include "base/logging.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/mac/scoped_ioobject.h"
 
 namespace content {
 
 namespace {
 
@@ skipping 73 matching lines @@
   // Remove the notification port from the message runloop.
   CFRunLoopRemoveSource(CFRunLoopGetCurrent(),
                         IONotificationPortGetRunLoopSource(notification_port_),
                         kCFRunLoopCommonModes);
 
   // Destroy the notification port allocated by IONotificationPortCreate.
   IONotificationPortDestroy(notification_port_);
 }
 
 void DeviceMonitorMac::RegisterAudioServices() {
-  CFMutableDictionaryRef dictionary =
-      IOServiceMatching(kIOAudioDeviceClassName);
-  RegisterServices(dictionary, &AudioDeviceCallback);
+  // We can't use IOService for audio since IOKit notification will come prior
+  // to the driver is actually fully initialized, and this has two issues:
+  // 1, device enumeration is not correct.
+  // 2, it might crash if the device is being enumerated at the same time as
+  //    as being initialized. See issue 153411 for details.
+  AudioObjectPropertyAddress property = {
+    kAudioHardwarePropertyDevices,
+    kAudioObjectPropertyScopeGlobal,
+    kAudioObjectPropertyElementMaster
+  };
+  AudioObjectAddPropertyListener(kAudioObjectSystemObject, &property,
+                                 &AudioDeviceCallback, this);
 }
 
 void DeviceMonitorMac::RegisterVideoServices() {
   CFMutableDictionaryRef dictionary = CreateMatchingDictionaryForUSBDevices(
       kUSBVideoInterfaceClass, kUSBVideoControlSubClass);
   RegisterServices(dictionary, &VideoDeviceCallback);
 }
 
 void DeviceMonitorMac::RegisterServices(CFMutableDictionaryRef dictionary,
                                         IOServiceMatchingCallback callback) {
@@ skipping 13 matching lines @@
                                 callback,
                                 this,
                                 &service);
 
     // Store the pointer of the object to release the memory when shutting
     // down the services.
     notification_iterators_.push_back(&service);
   }
 }
 
-void DeviceMonitorMac::AudioDeviceCallback(void *context,
-                                           io_iterator_t iterator) {
- for (base::mac::ScopedIOObject<io_service_t> object(IOIteratorNext(iterator));
-      object;
-      object.reset(IOIteratorNext(iterator))) {
-    if (context) {
-      reinterpret_cast<DeviceMonitorMac*>(context)->NotifyDeviceChanged(
-          base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
+OSStatus DeviceMonitorMac::AudioDeviceCallback(
+    AudioObjectID object, UInt32 size,
+    const AudioObjectPropertyAddress addresses[], void* context) {
+  for (UInt32 i = 0; i < size; ++i) {
+    if (addresses[i].mSelector == kAudioHardwarePropertyDevices) {
+      if (context) {
+        reinterpret_cast<DeviceMonitorMac*>(context)->NotifyDeviceChanged(
+            base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
+        break;
+      }
     }
   }
+
+  return noErr;
 }
 
 void DeviceMonitorMac::VideoDeviceCallback(void *context,
                                            io_iterator_t iterator) {
   for (base::mac::ScopedIOObject<io_service_t> object(IOIteratorNext(iterator));
        object;
        object.reset(IOIteratorNext(iterator))) {
     if (context) {
       reinterpret_cast<DeviceMonitorMac*>(context)->NotifyDeviceChanged(
           base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE);
     }
   }
 }
 
 void DeviceMonitorMac::NotifyDeviceChanged(
     base::SystemMonitor::DeviceType type) {
   // TODO(xians): Remove the global variable for SystemMonitor.
   base::SystemMonitor::Get()->ProcessDevicesChanged(type);
 }
 
 }  // namespace content