add device notification to Mac

content/browser/device_monitor_mac.mm

Index: content/browser/device_monitor_mac.mm
diff --git a/content/browser/device_monitor_mac.mm b/content/browser/device_monitor_mac.mm
new file mode 100644
index 0000000000000000000000000000000000000000..dfc6ca1c65d1bf67a0737c9d178dbffdabc62831
--- /dev/null
+++ b/content/browser/device_monitor_mac.mm
@@ -0,0 +1,174 @@
+// 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 "base/logging.h"
+#include "base/system_monitor/system_monitor.h"
+
+#include <CoreFoundation/CFNumber.h>

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

shouldn't these be above the chrome includes?

[no longer working on chromium, 2012/08/03 13:07:07]

done.

+#include <CoreFoundation/CoreFoundation.h>
+#include <IOKit/usb/IOUSBLib.h>
+
+namespace content {
+
+namespace {
+
+DeviceMonitorMac* InstanceFromContext(void* context) {
+  return reinterpret_cast<DeviceMonitorMac*>(context);
+}
+
+void AddValueToDictionary(CFMutableDictionaryRef dictionary,
+                          SInt32 code,
+                          const void *key) {
+  CFNumberRef number_ref = CFNumberCreate(kCFAllocatorDefault,
+                                          kCFNumberSInt32Type,
+                                          &code);
+  if (!number_ref) {
+    NOTREACHED() << "failed to create CFNumberRef for " << code;
+    return;
+  }
+
+  CFDictionaryAddValue(dictionary, key, number_ref);
+  CFRelease(number_ref);
+
+  dictionary = (CFMutableDictionaryRef)(CFRetain(dictionary));

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

fix cast or is this how things are done in mm land? :)

[no longer working on chromium, 2012/08/03 13:07:07]

neither static_cast nor reinterpret_cast passes the compiler, though I am not
sure if it is correct. Lets wait for comments from other reviewers.

+}
+
+void VideoDeviceChangedCallback(void *context, io_iterator_t devices) {

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

void* context.

In order to allow this method to call the private NotifyVideoDeviceChanged
method (assuming you do that), you should make this a static method in the
class.

[no longer working on chromium, 2012/08/03 13:07:07]

Done.

+  io_object_t thisObject;
+  while ((thisObject = IOIteratorNext(devices))) {
+    if (context)
+      InstanceFromContext(context)->NotifyVideoDeviceChanged();
+
+    IOObjectRelease(thisObject);
+  }
+}
+
+void AudioDeviceChangedCallback(void *context, io_iterator_t devices) {

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

same as above.

[no longer working on chromium, 2012/08/03 13:07:07]

Done.

+  io_object_t thisObject;
+  while ((thisObject = IOIteratorNext(devices))) {
+     if (context)
+      InstanceFromContext(context)->NotifyAudioDeviceChanged();
+
+    IOObjectRelease(thisObject);
+  }
+}
+
+}  // namespace
+
+DeviceMonitorMac::DeviceMonitorMac() {
+  CFRunLoopRef runloop = CFRunLoopGetCurrent ();

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

no space before ()

[no longer working on chromium, 2012/08/03 13:07:07]

Done.

+  CFRetain (runloop);
+
+  // Add the notification port to the run loop.
+  IONotificationPortRef notification_port =
+      IONotificationPortCreate (kIOMasterPortDefault);

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

same here. please fix throughout

[no longer working on chromium, 2012/08/03 13:07:07]

Done.

+  CFRunLoopSourceRef notification_cfsource =
+      IONotificationPortGetRunLoopSource (notification_port);
+
+  RegisterVideoCallbacks(notification_port);
+  RegisterAudioCallbacks(notification_port);
+  CFRunLoopAddSource(runloop, notification_cfsource, kCFRunLoopCommonModes);
+}
+
+void DeviceMonitorMac::RegisterVideoCallbacks(IONotificationPortRef port) {
+  SInt32 interface_class_code = kUSBVideoInterfaceClass;
+  SInt32 interface_subclass_code = kUSBVideoControlSubClass;
+  CFMutableDictionaryRef matching_dictionary = IOServiceMatching(
+      kIOUSBInterfaceClassName);
+  AddValueToDictionary(matching_dictionary, interface_class_code,
+                       CFSTR(kUSBInterfaceClass));
+  AddValueToDictionary(matching_dictionary, interface_subclass_code,
+                       CFSTR(kUSBInterfaceSubClass));
+
+  // Add a callback which will be called when a video device is plugged in.
+  io_iterator_t new_devices_iterator = 0;
+  kern_return_t err = IOServiceAddMatchingNotification(
+      port,
+      kIOMatchedNotification,
+      matching_dictionary,
+      &VideoDeviceChangedCallback,
+      this,
+      &new_devices_iterator);
+  if (err) {
+    NOTREACHED() << "Failed to register the video IO mached notification";
+    return;
+  }
+  VideoDeviceChangedCallback(NULL, new_devices_iterator);
+
+  // Add a callback which will be called when a video device is terminated.
+  io_iterator_t lost_devices_iterator = 0;
+  err = IOServiceAddMatchingNotification(
+      port,
+      kIOTerminatedNotification,
+      matching_dictionary,
+      &VideoDeviceChangedCallback,
+      this,
+      &lost_devices_iterator);
+  if (err) {
+    NOTREACHED() << "Failed to register the video IO terminated notification";
+    return;
+  }
+  VideoDeviceChangedCallback(NULL, lost_devices_iterator);
+}
+
+void DeviceMonitorMac::RegisterAudioCallbacks(IONotificationPortRef port) {
+  SInt32 interface_class_code = kUSBAudioInterfaceClass;
+  SInt32 interface_subclass_code = kUSBAudioControlSubClass;
+  CFMutableDictionaryRef matching_dictionary = IOServiceMatching(
+      kIOUSBInterfaceClassName);
+  AddValueToDictionary(matching_dictionary, interface_class_code,
+                       CFSTR(kUSBInterfaceClass));
+  AddValueToDictionary(matching_dictionary, interface_subclass_code,
+                       CFSTR(kUSBInterfaceSubClass));
+
+  // Add a callback which will be called when a audio device is plugged in.
+  io_iterator_t added_devices_iterator = 0;
+  kern_return_t err = IOServiceAddMatchingNotification(
+      port,
+      kIOMatchedNotification,
+      matching_dictionary,
+      &AudioDeviceChangedCallback,
+      this,
+      &added_devices_iterator);
+  if (err) {
+    NOTREACHED() << "Failed to register the audio IO mached notification";
+    return;
+  }
+  // Iterate over set of matching devices to access already-present devices
+  // and to arm the notification.
+  AudioDeviceChangedCallback(NULL, added_devices_iterator);
+
+  // Add a callback which will be called when a audio device is terminated.
+  io_iterator_t removed_devices_iterator = 0;
+  err = IOServiceAddMatchingNotification(
+      port,
+      kIOTerminatedNotification,
+      matching_dictionary,
+      &AudioDeviceChangedCallback,
+      this,
+      &removed_devices_iterator);
+  if (err) {
+     NOTREACHED() << "Failed to register the audio IO terminated notification";

[tommi (sloooow) - chröme, 2012/08/03 11:24:29]

fix indent

[no longer working on chromium, 2012/08/03 13:07:07]

Done.

+    return;
+  }
+  // Iterate over set of matching devices to release each one and to
+  // arm the notification.
+  AudioDeviceChangedCallback(NULL, removed_devices_iterator);
+}
+
+void DeviceMonitorMac::NotifyAudioDeviceChanged() {
+  base::SystemMonitor* monitor = base::SystemMonitor::Get();
+  monitor->ProcessDevicesChanged(base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
+}
+
+void DeviceMonitorMac::NotifyVideoDeviceChanged() {
+  base::SystemMonitor* monitor = base::SystemMonitor::Get();
+  monitor->ProcessDevicesChanged(base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE);
+}
+
+DeviceMonitorMac::~DeviceMonitorMac() {}
+
+}  // namespace content