Complete //device/bt implementation for hosting local GATT attributes.

device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc

Index: device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc
diff --git a/device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc b/device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc
index 239be9ccc133a7015739d2da101c971336b72e32..a0bce309daa129200ac0720de88b8a649eb73b38 100644
--- a/device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc
+++ b/device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.cc
@@ -5,18 +5,16 @@
 #include "device/bluetooth/dbus/bluetooth_gatt_descriptor_service_provider.h"
 
 #include <stddef.h>
-
-#include <memory>
-#include <utility>
+#include <iostream>
 
 #include "base/bind.h"
+#include "base/callback.h"
 #include "base/logging.h"
-#include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string_util.h"
 #include "base/threading/platform_thread.h"
 #include "dbus/exported_object.h"
-#include "dbus/message.h"
 #include "device/bluetooth/dbus/bluez_dbus_manager.h"
 #include "device/bluetooth/dbus/fake_bluetooth_gatt_descriptor_service_provider.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
@@ -36,7 +34,7 @@ class BluetoothGattDescriptorServiceProviderImpl
   BluetoothGattDescriptorServiceProviderImpl(
       dbus::Bus* bus,
       const dbus::ObjectPath& object_path,
-      Delegate* delegate,
+      BluetoothGattServiceBlueZ::AttributeValueDelegate* delegate,
       const std::string& uuid,
       const std::vector<std::string>& permissions,
       const dbus::ObjectPath& characteristic_path)
@@ -160,7 +158,7 @@ class BluetoothGattDescriptorServiceProviderImpl
     // If getting the "Value" property, obtain the value from the delegate.
     if (property_name == bluetooth_gatt_descriptor::kValueProperty) {
       DCHECK(delegate_);
-      delegate_->GetDescriptorValue(
+      delegate_->GetValue(
           base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnGet,
                      weak_ptr_factory_.GetWeakPtr(), method_call,
                      response_sender),
@@ -262,7 +260,7 @@ class BluetoothGattDescriptorServiceProviderImpl
     // Pass the set request onto the delegate.
     std::vector<uint8_t> value(bytes, bytes + length);
     DCHECK(delegate_);
-    delegate_->SetDescriptorValue(
+    delegate_->SetValue(
         value, base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnSet,
                           weak_ptr_factory_.GetWeakPtr(), method_call,
                           response_sender),
@@ -304,7 +302,7 @@ class BluetoothGattDescriptorServiceProviderImpl
     // Try to obtain the value from the delegate. We will construct the
     // response in the success callback.
     DCHECK(delegate_);
-    delegate_->GetDescriptorValue(
+    delegate_->GetValue(
         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnGetAll,
                    weak_ptr_factory_.GetWeakPtr(), method_call,
                    response_sender),
@@ -333,11 +331,20 @@ class BluetoothGattDescriptorServiceProviderImpl
     std::unique_ptr<dbus::Response> response =
         dbus::Response::FromMethodCall(method_call);
     dbus::MessageWriter writer(response.get());
+    WriteProperties(&writer, &value);
+    response_sender.Run(std::move(response));
+  }
+
+  // Writes the characteristics's properties into the provided writer. If
+  // value is not null, it is written also, otherwise no value property is
+  // written.
+  void WriteProperties(dbus::MessageWriter* writer,
+                       const std::vector<uint8_t>* value) override {
     dbus::MessageWriter array_writer(NULL);
     dbus::MessageWriter dict_entry_writer(NULL);
     dbus::MessageWriter variant_writer(NULL);
 
-    writer.OpenArray("{sv}", &array_writer);
+    writer->OpenArray("{sv}", &array_writer);
 
     array_writer.OpenDictEntry(&dict_entry_writer);
     dict_entry_writer.AppendString(bluetooth_gatt_descriptor::kUUIDProperty);
@@ -350,18 +357,17 @@ class BluetoothGattDescriptorServiceProviderImpl
     dict_entry_writer.AppendVariantOfObjectPath(characteristic_path_);
     array_writer.CloseContainer(&dict_entry_writer);
 
-    array_writer.OpenDictEntry(&dict_entry_writer);
-    dict_entry_writer.AppendString(bluetooth_gatt_descriptor::kValueProperty);
-    dict_entry_writer.OpenVariant("ay", &variant_writer);
-    variant_writer.AppendArrayOfBytes(value.data(), value.size());
-    dict_entry_writer.CloseContainer(&variant_writer);
-    array_writer.CloseContainer(&dict_entry_writer);
+    if (value) {
+      array_writer.OpenDictEntry(&dict_entry_writer);
+      dict_entry_writer.AppendString(bluetooth_gatt_descriptor::kValueProperty);
+      dict_entry_writer.OpenVariant("ay", &variant_writer);
+      variant_writer.AppendArrayOfBytes(value->data(), value->size());
+      dict_entry_writer.CloseContainer(&variant_writer);
+      array_writer.CloseContainer(&dict_entry_writer);
+    }
 
     // TODO(armansito): Process "Permissions" property.
-
-    writer.CloseContainer(&array_writer);
-
-    response_sender.Run(std::move(response));
+    writer->CloseContainer(&array_writer);
   }
 
   // Called by the Delegate in response to a successful method call to get the
@@ -401,6 +407,8 @@ class BluetoothGattDescriptorServiceProviderImpl
     response_sender.Run(std::move(error_response));
   }
 
+  const dbus::ObjectPath& object_path() const override { return object_path_; }
+
   // Origin thread (i.e. the UI thread in production).
   base::PlatformThreadId origin_thread_id_;
 
@@ -414,7 +422,7 @@ class BluetoothGattDescriptorServiceProviderImpl
   // Incoming methods to get and set the "Value" property are passed on to the
   // delegate and callbacks passed to generate a reply. |delegate_| is generally
   // the object that owns this one and must outlive it.
-  Delegate* delegate_;
+  BluetoothGattServiceBlueZ::AttributeValueDelegate* delegate_;
 
   // D-Bus object path of object we are exporting, kept so we can unregister
   // again in our destructor.
@@ -448,7 +456,7 @@ BluetoothGattDescriptorServiceProvider*
 BluetoothGattDescriptorServiceProvider::Create(
     dbus::Bus* bus,
     const dbus::ObjectPath& object_path,
-    Delegate* delegate,
+    BluetoothGattServiceBlueZ::AttributeValueDelegate* delegate,
     const std::string& uuid,
     const std::vector<std::string>& permissions,
     const dbus::ObjectPath& characteristic_path) {