arc: bluetooth: Implement Gatt notify

components/arc/bluetooth/arc_bluetooth_bridge.cc

Index: components/arc/bluetooth/arc_bluetooth_bridge.cc
diff --git a/components/arc/bluetooth/arc_bluetooth_bridge.cc b/components/arc/bluetooth/arc_bluetooth_bridge.cc
index 45228c0379ccf23323cfdf50c117b724f27ca508..ae78c5e8e39aca02b158f1c860158a3dbb077cc8 100644
--- a/components/arc/bluetooth/arc_bluetooth_bridge.cc
+++ b/components/arc/bluetooth/arc_bluetooth_bridge.cc
@@ -45,7 +45,8 @@ using device::BluetoothRemoteGattService;
 using device::BluetoothUUID;
 
 namespace {
-const int kMinBtleVersion = 1;
+enum { kMinBtleVersion = 1 };
+enum { kMinBtleNotifyVersion = 2 };
 const uint32_t kGattReadPermission =
     BluetoothGattCharacteristic::Permission::PERMISSION_READ |
     BluetoothGattCharacteristic::Permission::PERMISSION_READ_ENCRYPTED |
@@ -257,7 +258,31 @@ void ArcBluetoothBridge::GattCharacteristicValueChanged(
     BluetoothAdapter* adapter,
     BluetoothRemoteGattCharacteristic* characteristic,
     const std::vector<uint8_t>& value) {
-  // Placeholder for GATT client functionality
+  if (!HasBluetoothInstance())
+    return;
+
+  if (arc_bridge_service()->bluetooth_version() < kMinBtleNotifyVersion) {
+    LOG(WARNING) << "Bluetooth instance is too old and does not support notify";
+    return;
+  }
+  BluetoothRemoteGattService* service = characteristic->GetService();
+  BluetoothDevice* device = service->GetDevice();
+  mojom::BluetoothAddressPtr address =
+      mojom::BluetoothAddress::From(device->GetAddress());
+  mojom::BluetoothGattServiceIDPtr service_id =
+      mojom::BluetoothGattServiceID::New();
+  service_id->is_primary = service->IsPrimary();
+  service_id->id = mojom::BluetoothGattID::New();
+  service_id->id->inst_id = ConvertGattIdentifierToId(service->GetIdentifier());
+  service_id->id->uuid = mojom::BluetoothUUID::From(service->GetUUID());
+
+  mojom::BluetoothGattIDPtr char_id = mojom::BluetoothGattID::New();
+  char_id->inst_id = ConvertGattIdentifierToId(characteristic->GetIdentifier());
+  char_id->uuid = mojom::BluetoothUUID::From(characteristic->GetUUID());
+
+  arc_bridge_service()->bluetooth_instance()->OnGattNotify(
+      std::move(address), std::move(service_id), std::move(char_id),
+      true /* is_notify */, mojo::Array<uint8_t>::From(value));
 }
 
 void ArcBluetoothBridge::GattDescriptorValueChanged(
@@ -902,6 +927,14 @@ void ArcBluetoothBridge::WriteGattDescriptor(
   DCHECK(descriptor);
   DCHECK(descriptor->GetPermissions() & kGattWritePermission);
 
+  // Chrome does not support writing to CCC Descriptor
+  // Always return success when encounter this.
+  if (descriptor->GetUUID() ==

[rkc, 2016/06/23 19:36:38]

This is definitely going to break behavior in some apps. I am fine with this
going in for M53, but please create a P1 bug for this and add it here in a TODO.
We should discuss potential solutions and see if there is a simple one we can
get in for 53 later.


We could either simulate the write with calling StartNotify or we could just
remove this check:
http://git.kernel.org/cgit/bluetooth/bluez.git/tree/src/gatt-client.c#n588 but
that can break notification behavior on BlueZ. More investigation is needed.

+      BluetoothGattDescriptor::ClientCharacteristicConfigurationUuid()) {
+    OnGattWriteDone(callback);
+    return;
+  }
+
   descriptor->WriteRemoteDescriptor(
       value->value.To<std::vector<uint8_t>>(),
       base::Bind(&ArcBluetoothBridge::OnGattWriteDone,