BluetoothAdapterMac::LowEnergyDeviceUpdated() Implemented

device/bluetooth/bluetooth_adapter_mac.mm

 // Copyright 2013 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 "device/bluetooth/bluetooth_adapter_mac.h"
 
 #import <IOBluetooth/objc/IOBluetoothDevice.h>
 #import <IOBluetooth/objc/IOBluetoothHostController.h>
 
 #include <string>
@@ skipping 384 matching lines @@
   // Only notify observers once per device.
   if (devices_.count(device_address))
     return;
 
   devices_[device_address] = new BluetoothClassicDeviceMac(device);
   FOR_EACH_OBSERVER(BluetoothAdapter::Observer,
                     observers_,
                     DeviceAdded(this, devices_[device_address]));
 }
 
-// TODO(krstnmnlsn): Implement method. http://crbug.com/496987.
 void BluetoothAdapterMac::LowEnergyDeviceUpdated(
     CBPeripheral* peripheral,
     NSDictionary* advertisementData,
     int rssi) {
+  std::string device_address =
+      BluetoothLowEnergyDeviceMac::GetPeripheralHashAddress(peripheral);
+  BluetoothDevice*& device_reference = devices_[device_address];
+
+  if (!device_reference) {
+    // A new device has been found.
+    device_reference =
+        new BluetoothLowEnergyDeviceMac(peripheral, advertisementData, rssi);
+    FOR_EACH_OBSERVER(BluetoothAdapter::Observer, observers_,

[scheib, 2015/07/13 18:24:39]

Only one of DeviceAdded or DeviceChanged should be called. Either add a return
to this block, or adjust the following blocks to be else if {...} else {...}

[krstnmnlsn, 2015/07/13 20:40:43]

Right, thanks.  This is what I get for cutting and pasting code around...

+                      DeviceAdded(this, device_reference));
+
+  } else {
+    if (static_cast<BluetoothLowEnergyDeviceMac*>(device_reference)
+            ->GetIdentifier() !=
+        BluetoothLowEnergyDeviceMac::GetPeripheralIdentifier(peripheral)) {
+      // Collision, two identifiers map to the same hash address.  With a 48 bit
+      // hash the probability of this occuring with 10,000 devices
+      // simultaneously present is 1e-6 (see
+      // https://en.wikipedia.org/wiki/Birthday_problem#Probability_table).  We
+      // ignore the second device by returning.
+      return;
+    }
+    // A device has an update.
+    static_cast<BluetoothLowEnergyDeviceMac*>(device_reference)
+        ->Update(peripheral, advertisementData, rssi);
+    FOR_EACH_OBSERVER(BluetoothAdapter::Observer, observers_,
+                      DeviceChanged(this, device_reference));
+    return;
+  }
 }
 
 void BluetoothAdapterMac::RemoveTimedOutDevices() {
   // Notify observers if any previously seen devices are no longer available,
   // i.e. if they are no longer paired, connected, nor recently discovered via
   // an inquiry.
   std::set<std::string> removed_devices;
   for (DevicesMap::iterator it = devices_.begin(); it != devices_.end(); ++it) {
     BluetoothDevice* device = it->second;
     if (device->IsPaired() || device->IsConnected())
@@ skipping 18 matching lines @@
 }
 
 void BluetoothAdapterMac::AddPairedDevices() {
   // Add any new paired devices.
   for (IOBluetoothDevice* device in [IOBluetoothDevice pairedDevices]) {
     ClassicDeviceAdded(device);
   }
 }
 
 }  // namespace device