chromeos/dbus/bluetooth_gatt_descriptor_service_provider.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chromeos/dbus/bluetooth_gatt_descriptor_service_provider.h"
   6
   7 #include "base/bind.h"
   8 #include "base/logging.h"
   9 #include "base/memory/weak_ptr.h"
  10 #include "base/strings/string_util.h"
  11 #include "base/threading/platform_thread.h"
  12 #include "chromeos/dbus/dbus_thread_manager.h"
  13 #include "chromeos/dbus/fake_bluetooth_gatt_descriptor_service_provider.h"
  14 #include "dbus/exported_object.h"
  15 #include "dbus/message.h"
  16 #include "third_party/cros_system_api/dbus/service_constants.h"
  17
  18 namespace chromeos {
  19 namespace {
  20 const char kErrorInvalidArgs[] =
  21     "org.freedesktop.DBus.Error.InvalidArgs";
  22 const char kErrorPropertyReadOnly[] =
  23     "org.freedesktop.DBus.Error.PropertyReadOnly";
  24 const char kErrorFailed[] =
  25     "org.freedesktop.DBus.Error.Failed";
  26 }  // namespace
  27
  28 // The BluetoothGattDescriptorServiceProvider implementation used in production.
  29 class BluetoothGattDescriptorServiceProviderImpl
  30     : public BluetoothGattDescriptorServiceProvider {
  31  public:
  32   BluetoothGattDescriptorServiceProviderImpl(
  33       dbus::Bus* bus,
  34       const dbus::ObjectPath& object_path,
  35       Delegate* delegate,
  36       const std::string& uuid,
  37       const std::vector<std::string>& permissions,
  38       const dbus::ObjectPath& characteristic_path)
  39       : origin_thread_id_(base::PlatformThread::CurrentId()),
  40         uuid_(uuid),
  41         bus_(bus),
  42         delegate_(delegate),
  43         object_path_(object_path),
  44         characteristic_path_(characteristic_path),
  45         weak_ptr_factory_(this) {
  46     VLOG(1) << "Created Bluetooth GATT characteristic descriptor: "
  47             << object_path.value() << " UUID: " << uuid;
  48     DCHECK(bus_);
  49     DCHECK(delegate_);
  50     DCHECK(!uuid_.empty());
  51     DCHECK(object_path_.IsValid());
  52     DCHECK(characteristic_path_.IsValid());
  53     DCHECK(StartsWithASCII(
  54         object_path_.value(), characteristic_path_.value() + "/", true));
  55
  56     exported_object_ = bus_->GetExportedObject(object_path_);
  57
  58     exported_object_->ExportMethod(
  59         dbus::kDBusPropertiesInterface,
  60         dbus::kDBusPropertiesGet,
  61         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::Get,
  62                    weak_ptr_factory_.GetWeakPtr()),
  63         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnExported,
  64                    weak_ptr_factory_.GetWeakPtr()));
  65
  66     exported_object_->ExportMethod(
  67         dbus::kDBusPropertiesInterface,
  68         dbus::kDBusPropertiesSet,
  69         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::Set,
  70                    weak_ptr_factory_.GetWeakPtr()),
  71         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnExported,
  72                    weak_ptr_factory_.GetWeakPtr()));
  73
  74     exported_object_->ExportMethod(
  75         dbus::kDBusPropertiesInterface,
  76         dbus::kDBusPropertiesGetAll,
  77         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::GetAll,
  78                    weak_ptr_factory_.GetWeakPtr()),
  79         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnExported,
  80                    weak_ptr_factory_.GetWeakPtr()));
  81   }
  82
  83   ~BluetoothGattDescriptorServiceProviderImpl() override {
  84     VLOG(1) << "Cleaning up Bluetooth GATT characteristic descriptor: "
  85             << object_path_.value();
  86     bus_->UnregisterExportedObject(object_path_);
  87   }
  88
  89   // BluetoothGattDescriptorServiceProvider override.
  90   void SendValueChanged(const std::vector<uint8>& value) override {
  91     VLOG(2) << "Emitting a PropertiesChanged signal for descriptor value.";
  92     dbus::Signal signal(
  93         dbus::kDBusPropertiesInterface,
  94         dbus::kDBusPropertiesChangedSignal);
  95     dbus::MessageWriter writer(&signal);
  96     dbus::MessageWriter array_writer(NULL);
  97     dbus::MessageWriter dict_entry_writer(NULL);
  98     dbus::MessageWriter variant_writer(NULL);
  99
 100     // interface_name
 101     writer.AppendString(
 102         bluetooth_gatt_descriptor::kBluetoothGattDescriptorInterface);
 103
 104     // changed_properties
 105     writer.OpenArray("{sv}", &array_writer);
 106     array_writer.OpenDictEntry(&dict_entry_writer);
 107     dict_entry_writer.AppendString(bluetooth_gatt_descriptor::kValueProperty);
 108     dict_entry_writer.OpenVariant("ay", &variant_writer);
 109     variant_writer.AppendArrayOfBytes(value.data(), value.size());
 110     dict_entry_writer.CloseContainer(&variant_writer);
 111     array_writer.CloseContainer(&dict_entry_writer);
 112     writer.CloseContainer(&array_writer);
 113
 114     // invalidated_properties.
 115     writer.OpenArray("s", &array_writer);
 116     writer.CloseContainer(&array_writer);
 117
 118     exported_object_->SendSignal(&signal);
 119   }
 120
 121  private:
 122   // Returns true if the current thread is on the origin thread.
 123   bool OnOriginThread() {
 124     return base::PlatformThread::CurrentId() == origin_thread_id_;
 125   }
 126
 127   // Called by dbus:: when the Bluetooth daemon fetches a single property of
 128   // the descriptor.
 129   void Get(dbus::MethodCall* method_call,
 130            dbus::ExportedObject::ResponseSender response_sender) {
 131     VLOG(2) << "BluetoothGattDescriptorServiceProvider::Get: "
 132             << object_path_.value();
 133     DCHECK(OnOriginThread());
 134
 135     dbus::MessageReader reader(method_call);
 136
 137     std::string interface_name;
 138     std::string property_name;
 139     if (!reader.PopString(&interface_name) ||
 140         !reader.PopString(&property_name) ||
 141         reader.HasMoreData()) {
 142       scoped_ptr<dbus::ErrorResponse> error_response =
 143           dbus::ErrorResponse::FromMethodCall(
 144               method_call, kErrorInvalidArgs, "Expected 'ss'.");
 145       response_sender.Run(error_response.Pass());
 146       return;
 147     }
 148
 149     // Only the GATT descriptor interface is supported.
 150     if (interface_name !=
 151         bluetooth_gatt_descriptor::kBluetoothGattDescriptorInterface) {
 152       scoped_ptr<dbus::ErrorResponse> error_response =
 153           dbus::ErrorResponse::FromMethodCall(
 154               method_call, kErrorInvalidArgs,
 155               "No such interface: '" + interface_name + "'.");
 156       response_sender.Run(error_response.Pass());
 157       return;
 158     }
 159
 160     // If getting the "Value" property, obtain the value from the delegate.
 161     if (property_name == bluetooth_gatt_descriptor::kValueProperty) {
 162       DCHECK(delegate_);
 163       delegate_->GetDescriptorValue(
 164           base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnGet,
 165                      weak_ptr_factory_.GetWeakPtr(),
 166                      method_call, response_sender),
 167           base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnFailure,
 168                      weak_ptr_factory_.GetWeakPtr(),
 169                      method_call, response_sender));
 170       return;
 171     }
 172
 173     scoped_ptr<dbus::Response> response =
 174         dbus::Response::FromMethodCall(method_call);
 175     dbus::MessageWriter writer(response.get());
 176     dbus::MessageWriter variant_writer(NULL);
 177
 178     // TODO(armansito): Process the "Permissions" property below.
 179     if (property_name == bluetooth_gatt_descriptor::kUUIDProperty) {
 180       writer.OpenVariant("s", &variant_writer);
 181       variant_writer.AppendString(uuid_);
 182       writer.CloseContainer(&variant_writer);
 183     } else if (property_name ==
 184                bluetooth_gatt_descriptor::kCharacteristicProperty) {
 185       writer.OpenVariant("o", &variant_writer);
 186       variant_writer.AppendObjectPath(characteristic_path_);
 187       writer.CloseContainer(&variant_writer);
 188     } else {
 189       response = dbus::ErrorResponse::FromMethodCall(
 190           method_call,
 191           kErrorInvalidArgs,
 192           "No such property: '" + property_name + "'.");
 193     }
 194
 195     response_sender.Run(response.Pass());
 196   }
 197
 198   // Called by dbus:: when the Bluetooth daemon sets a single property of the
 199   // descriptor.
 200   void Set(dbus::MethodCall* method_call,
 201            dbus::ExportedObject::ResponseSender response_sender) {
 202     VLOG(2) << "BluetoothGattDescriptorServiceProvider::Set: "
 203             << object_path_.value();
 204     DCHECK(OnOriginThread());
 205
 206     dbus::MessageReader reader(method_call);
 207
 208     std::string interface_name;
 209     std::string property_name;
 210     dbus::MessageReader variant_reader(NULL);
 211     if (!reader.PopString(&interface_name) ||
 212         !reader.PopString(&property_name) ||
 213         !reader.PopVariant(&variant_reader) ||
 214         reader.HasMoreData()) {
 215       scoped_ptr<dbus::ErrorResponse> error_response =
 216           dbus::ErrorResponse::FromMethodCall(
 217               method_call, kErrorInvalidArgs, "Expected 'ssv'.");
 218       response_sender.Run(error_response.Pass());
 219       return;
 220     }
 221
 222     // Only the GATT descriptor interface is allowed.
 223     if (interface_name !=
 224         bluetooth_gatt_descriptor::kBluetoothGattDescriptorInterface) {
 225       scoped_ptr<dbus::ErrorResponse> error_response =
 226           dbus::ErrorResponse::FromMethodCall(
 227               method_call, kErrorInvalidArgs,
 228               "No such interface: '" + interface_name + "'.");
 229       response_sender.Run(error_response.Pass());
 230       return;
 231     }
 232
 233     // Only the "Value" property is writeable.
 234     if (property_name != bluetooth_gatt_descriptor::kValueProperty) {
 235       std::string error_name;
 236       std::string error_message;
 237       if (property_name == bluetooth_gatt_descriptor::kUUIDProperty ||
 238           property_name == bluetooth_gatt_descriptor::kCharacteristicProperty) {
 239         error_name = kErrorPropertyReadOnly;
 240         error_message = "Read-only property: '" + property_name + "'.";
 241       } else {
 242         error_name = kErrorInvalidArgs;
 243         error_message = "No such property: '" + property_name + "'.";
 244       }
 245       scoped_ptr<dbus::ErrorResponse> error_response =
 246           dbus::ErrorResponse::FromMethodCall(
 247               method_call, error_name, error_message);
 248       response_sender.Run(error_response.Pass());
 249       return;
 250     }
 251
 252     // Obtain the value.
 253     const uint8* bytes = NULL;
 254     size_t length = 0;
 255     if (!variant_reader.PopArrayOfBytes(&bytes, &length)) {
 256       scoped_ptr<dbus::ErrorResponse> error_response =
 257           dbus::ErrorResponse::FromMethodCall(
 258               method_call, kErrorInvalidArgs,
 259               "Property '" + property_name + "' has type 'ay'.");
 260       response_sender.Run(error_response.Pass());
 261       return;
 262     }
 263
 264     // Pass the set request onto the delegate.
 265     std::vector<uint8> value(bytes, bytes + length);
 266     DCHECK(delegate_);
 267     delegate_->SetDescriptorValue(
 268         value,
 269         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnSet,
 270                    weak_ptr_factory_.GetWeakPtr(),
 271                    method_call, response_sender),
 272         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnFailure,
 273                    weak_ptr_factory_.GetWeakPtr(),
 274                    method_call, response_sender));
 275   }
 276
 277   // Called by dbus:: when the Bluetooth daemon fetches all properties of the
 278   // descriptor.
 279   void GetAll(dbus::MethodCall* method_call,
 280               dbus::ExportedObject::ResponseSender response_sender) {
 281     VLOG(2) << "BluetoothGattDescriptorServiceProvider::GetAll: "
 282             << object_path_.value();
 283     DCHECK(OnOriginThread());
 284
 285     dbus::MessageReader reader(method_call);
 286
 287     std::string interface_name;
 288     if (!reader.PopString(&interface_name) || reader.HasMoreData()) {
 289       scoped_ptr<dbus::ErrorResponse> error_response =
 290           dbus::ErrorResponse::FromMethodCall(
 291               method_call, kErrorInvalidArgs, "Expected 's'.");
 292       response_sender.Run(error_response.Pass());
 293       return;
 294     }
 295
 296     // Only the GATT descriptor interface is supported.
 297     if (interface_name !=
 298         bluetooth_gatt_descriptor::kBluetoothGattDescriptorInterface) {
 299       scoped_ptr<dbus::ErrorResponse> error_response =
 300           dbus::ErrorResponse::FromMethodCall(
 301               method_call, kErrorInvalidArgs,
 302               "No such interface: '" + interface_name + "'.");
 303       response_sender.Run(error_response.Pass());
 304       return;
 305     }
 306
 307     // Try to obtain the value from the delegate. We will construct the
 308     // response in the success callback.
 309     DCHECK(delegate_);
 310     delegate_->GetDescriptorValue(
 311         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnGetAll,
 312                    weak_ptr_factory_.GetWeakPtr(),
 313                    method_call, response_sender),
 314         base::Bind(&BluetoothGattDescriptorServiceProviderImpl::OnFailure,
 315                    weak_ptr_factory_.GetWeakPtr(),
 316                    method_call, response_sender));
 317   }
 318
 319   // Called by dbus:: when a method is exported.
 320   void OnExported(const std::string& interface_name,
 321                   const std::string& method_name,
 322                   bool success) {
 323     LOG_IF(WARNING, !success) << "Failed to export "
 324                               << interface_name << "." << method_name;
 325   }
 326
 327   // Called by the Delegate in response to a method to call to get all
 328   // properties, in which the delegate has successfully returned the
 329   // descriptor value.
 330   void OnGetAll(dbus::MethodCall* method_call,
 331                 dbus::ExportedObject::ResponseSender response_sender,
 332                 const std::vector<uint8>& value) {
 333     VLOG(2) << "Descriptor value obtained from delegate. Responding to "
 334             << "GetAll.";
 335
 336     scoped_ptr<dbus::Response> response =
 337         dbus::Response::FromMethodCall(method_call);
 338     dbus::MessageWriter writer(response.get());
 339     dbus::MessageWriter array_writer(NULL);
 340     dbus::MessageWriter dict_entry_writer(NULL);
 341     dbus::MessageWriter variant_writer(NULL);
 342
 343     writer.OpenArray("{sv}", &array_writer);
 344
 345     array_writer.OpenDictEntry(&dict_entry_writer);
 346     dict_entry_writer.AppendString(
 347         bluetooth_gatt_descriptor::kUUIDProperty);
 348     dict_entry_writer.AppendVariantOfString(uuid_);
 349     array_writer.CloseContainer(&dict_entry_writer);
 350
 351     array_writer.OpenDictEntry(&dict_entry_writer);
 352     dict_entry_writer.AppendString(
 353         bluetooth_gatt_descriptor::kCharacteristicProperty);
 354     dict_entry_writer.AppendVariantOfObjectPath(characteristic_path_);
 355     array_writer.CloseContainer(&dict_entry_writer);
 356
 357     array_writer.OpenDictEntry(&dict_entry_writer);
 358     dict_entry_writer.AppendString(
 359         bluetooth_gatt_descriptor::kValueProperty);
 360     dict_entry_writer.OpenVariant("ay", &variant_writer);
 361     variant_writer.AppendArrayOfBytes(value.data(), value.size());
 362     dict_entry_writer.CloseContainer(&variant_writer);
 363     array_writer.CloseContainer(&dict_entry_writer);
 364
 365     // TODO(armansito): Process "Permissions" property.
 366
 367     writer.CloseContainer(&array_writer);
 368
 369     response_sender.Run(response.Pass());
 370   }
 371
 372   // Called by the Delegate in response to a successful method call to get the
 373   // descriptor value.
 374   void OnGet(dbus::MethodCall* method_call,
 375              dbus::ExportedObject::ResponseSender response_sender,
 376              const std::vector<uint8>& value) {
 377     VLOG(2) << "Returning descriptor value obtained from delegate.";
 378     scoped_ptr<dbus::Response> response =
 379         dbus::Response::FromMethodCall(method_call);
 380     dbus::MessageWriter writer(response.get());
 381     dbus::MessageWriter variant_writer(NULL);
 382
 383     writer.OpenVariant("ay", &variant_writer);
 384     variant_writer.AppendArrayOfBytes(value.data(), value.size());
 385     writer.CloseContainer(&variant_writer);
 386
 387     response_sender.Run(response.Pass());
 388   }
 389
 390   // Called by the Delegate in response to a successful method call to set the
 391   // descriptor value.
 392   void OnSet(dbus::MethodCall* method_call,
 393              dbus::ExportedObject::ResponseSender response_sender) {
 394     VLOG(2) << "Successfully set descriptor value. Return success.";
 395     response_sender.Run(dbus::Response::FromMethodCall(method_call));
 396   }
 397
 398   // Called by the Delegate in response to a failed method call to get or set
 399   // the descriptor value.
 400   void OnFailure(dbus::MethodCall* method_call,
 401                  dbus::ExportedObject::ResponseSender response_sender) {
 402     VLOG(2) << "Failed to get/set descriptor value. Report error.";
 403     scoped_ptr<dbus::ErrorResponse> error_response =
 404         dbus::ErrorResponse::FromMethodCall(
 405             method_call, kErrorFailed,
 406             "Failed to get/set descriptor value.");
 407     response_sender.Run(error_response.Pass());
 408   }
 409
 410   // Origin thread (i.e. the UI thread in production).
 411   base::PlatformThreadId origin_thread_id_;
 412
 413   // 128-bit descriptor UUID of this object.
 414   std::string uuid_;
 415
 416   // D-Bus bus object is exported on, not owned by this object and must
 417   // outlive it.
 418   dbus::Bus* bus_;
 419
 420   // Incoming methods to get and set the "Value" property are passed on to the
 421   // delegate and callbacks passed to generate a reply. |delegate_| is generally
 422   // the object that owns this one and must outlive it.
 423   Delegate* delegate_;
 424
 425   // D-Bus object path of object we are exporting, kept so we can unregister
 426   // again in our destructor.
 427   dbus::ObjectPath object_path_;
 428
 429   // Object path of the GATT characteristic that the exported descriptor belongs
 430   // to.
 431   dbus::ObjectPath characteristic_path_;
 432
 433   // D-Bus object we are exporting, owned by this object.
 434   scoped_refptr<dbus::ExportedObject> exported_object_;
 435
 436   // Weak pointer factory for generating 'this' pointers that might live longer
 437   // than we do.
 438   // Note: This should remain the last member so it'll be destroyed and
 439   // invalidate its weak pointers before any other members are destroyed.
 440   base::WeakPtrFactory<BluetoothGattDescriptorServiceProviderImpl>
 441       weak_ptr_factory_;
 442
 443   DISALLOW_COPY_AND_ASSIGN(BluetoothGattDescriptorServiceProviderImpl);
 444 };
 445
 446 BluetoothGattDescriptorServiceProvider::
 447     BluetoothGattDescriptorServiceProvider() {
 448 }
 449
 450 BluetoothGattDescriptorServiceProvider::
 451     ~BluetoothGattDescriptorServiceProvider() {
 452 }
 453
 454 // static
 455 BluetoothGattDescriptorServiceProvider*
 456 BluetoothGattDescriptorServiceProvider::Create(
 457     dbus::Bus* bus,
 458     const dbus::ObjectPath& object_path,
 459     Delegate* delegate,
 460     const std::string& uuid,
 461     const std::vector<std::string>& permissions,
 462     const dbus::ObjectPath& characteristic_path) {
 463   if (!DBusThreadManager::Get()->IsUsingStub(DBusClientBundle::BLUETOOTH)) {
 464     return new BluetoothGattDescriptorServiceProviderImpl(
 465         bus, object_path, delegate, uuid, permissions, characteristic_path);
 466   }
 467   return new FakeBluetoothGattDescriptorServiceProvider(
 468       object_path, delegate, uuid, permissions, characteristic_path);
 469 }
 470
 471 }  // namespace chromeos