src/dbus/object_manager.cc

   1 // Copyright (c) 2013 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 "dbus/object_manager.h"
   6
   7 #include "base/bind.h"
   8 #include "base/location.h"
   9 #include "base/logging.h"
  10 #include "base/metrics/histogram.h"
  11 #include "base/strings/stringprintf.h"
  12 #include "base/task_runner_util.h"
  13 #include "dbus/bus.h"
  14 #include "dbus/dbus_statistics.h"
  15 #include "dbus/message.h"
  16 #include "dbus/object_proxy.h"
  17 #include "dbus/property.h"
  18 #include "dbus/scoped_dbus_error.h"
  19 #include "dbus/util.h"
  20
  21 namespace dbus {
  22
  23 ObjectManager::Object::Object()
  24   : object_proxy(NULL) {
  25 }
  26
  27 ObjectManager::Object::~Object() {
  28 }
  29
  30 ObjectManager::ObjectManager(Bus* bus,
  31                              const std::string& service_name,
  32                              const ObjectPath& object_path)
  33     : bus_(bus),
  34       service_name_(service_name),
  35       object_path_(object_path),
  36       setup_success_(false),
  37       cleanup_called_(false),
  38       weak_ptr_factory_(this) {
  39   DVLOG(1) << "Creating ObjectManager for " << service_name_
  40            << " " << object_path_.value();
  41   DCHECK(bus_);
  42   bus_->AssertOnOriginThread();
  43   object_proxy_ = bus_->GetObjectProxy(service_name_, object_path_);
  44   object_proxy_->SetNameOwnerChangedCallback(
  45       base::Bind(&ObjectManager::NameOwnerChanged,
  46                  weak_ptr_factory_.GetWeakPtr()));
  47
  48   // Set up a match rule and a filter function to handle PropertiesChanged
  49   // signals from the service. This is important to avoid any race conditions
  50   // that might cause us to miss PropertiesChanged signals once all objects are
  51   // initialized via GetManagedObjects.
  52   base::PostTaskAndReplyWithResult(
  53       bus_->GetDBusTaskRunner(),
  54       FROM_HERE,
  55       base::Bind(&ObjectManager::SetupMatchRuleAndFilter, this),
  56       base::Bind(&ObjectManager::OnSetupMatchRuleAndFilterComplete, this));
  57 }
  58
  59 ObjectManager::~ObjectManager() {
  60   // Clean up Object structures
  61   for (ObjectMap::iterator iter = object_map_.begin();
  62        iter != object_map_.end(); ++iter) {
  63     Object* object = iter->second;
  64
  65     for (Object::PropertiesMap::iterator piter = object->properties_map.begin();
  66          piter != object->properties_map.end(); ++piter) {
  67       PropertySet* properties = piter->second;
  68       delete properties;
  69     }
  70
  71     delete object;
  72   }
  73 }
  74
  75 void ObjectManager::RegisterInterface(const std::string& interface_name,
  76                                       Interface* interface) {
  77   interface_map_[interface_name] = interface;
  78 }
  79
  80 void ObjectManager::UnregisterInterface(const std::string& interface_name) {
  81   InterfaceMap::iterator iter = interface_map_.find(interface_name);
  82   if (iter != interface_map_.end())
  83     interface_map_.erase(iter);
  84 }
  85
  86 std::vector<ObjectPath> ObjectManager::GetObjects() {
  87   std::vector<ObjectPath> object_paths;
  88
  89   for (ObjectMap::iterator iter = object_map_.begin();
  90        iter != object_map_.end(); ++iter)
  91     object_paths.push_back(iter->first);
  92
  93   return object_paths;
  94 }
  95
  96 std::vector<ObjectPath> ObjectManager::GetObjectsWithInterface(
  97       const std::string& interface_name) {
  98   std::vector<ObjectPath> object_paths;
  99
 100   for (ObjectMap::iterator oiter = object_map_.begin();
 101        oiter != object_map_.end(); ++oiter) {
 102     Object* object = oiter->second;
 103
 104     Object::PropertiesMap::iterator piter =
 105         object->properties_map.find(interface_name);
 106     if (piter != object->properties_map.end())
 107       object_paths.push_back(oiter->first);
 108   }
 109
 110   return object_paths;
 111 }
 112
 113 ObjectProxy* ObjectManager::GetObjectProxy(const ObjectPath& object_path) {
 114   ObjectMap::iterator iter = object_map_.find(object_path);
 115   if (iter == object_map_.end())
 116     return NULL;
 117
 118   Object* object = iter->second;
 119   return object->object_proxy;
 120 }
 121
 122 PropertySet* ObjectManager::GetProperties(const ObjectPath& object_path,
 123                                           const std::string& interface_name) {
 124   ObjectMap::iterator iter = object_map_.find(object_path);
 125   if (iter == object_map_.end())
 126     return NULL;
 127
 128   Object* object = iter->second;
 129   Object::PropertiesMap::iterator piter =
 130       object->properties_map.find(interface_name);
 131   if (piter == object->properties_map.end())
 132     return NULL;
 133
 134   return piter->second;
 135 }
 136
 137 void ObjectManager::GetManagedObjects() {
 138   MethodCall method_call(kObjectManagerInterface,
 139                          kObjectManagerGetManagedObjects);
 140
 141   object_proxy_->CallMethod(
 142       &method_call,
 143       ObjectProxy::TIMEOUT_USE_DEFAULT,
 144       base::Bind(&ObjectManager::OnGetManagedObjects,
 145                  weak_ptr_factory_.GetWeakPtr()));
 146 }
 147
 148 void ObjectManager::CleanUp() {
 149   DCHECK(bus_);
 150   bus_->AssertOnDBusThread();
 151   DCHECK(!cleanup_called_);
 152
 153   cleanup_called_ = true;
 154
 155   if (!setup_success_)
 156     return;
 157
 158   if (!bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this))
 159     LOG(ERROR) << "Failed to remove filter function";
 160
 161   ScopedDBusError error;
 162   bus_->RemoveMatch(match_rule_, error.get());
 163   if (error.is_set())
 164     LOG(ERROR) << "Failed to remove match rule: " << match_rule_;
 165
 166   match_rule_.clear();
 167 }
 168
 169 void ObjectManager::InitializeObjects() {
 170   DCHECK(bus_);
 171   DCHECK(object_proxy_);
 172   DCHECK(setup_success_);
 173
 174   // |object_proxy_| is no longer valid if the Bus was shut down before this
 175   // call. Don't initiate any other action from the origin thread.
 176   if (cleanup_called_)
 177     return;
 178
 179   object_proxy_->ConnectToSignal(
 180       kObjectManagerInterface,
 181       kObjectManagerInterfacesAdded,
 182       base::Bind(&ObjectManager::InterfacesAddedReceived,
 183                  weak_ptr_factory_.GetWeakPtr()),
 184       base::Bind(&ObjectManager::InterfacesAddedConnected,
 185                  weak_ptr_factory_.GetWeakPtr()));
 186
 187   object_proxy_->ConnectToSignal(
 188       kObjectManagerInterface,
 189       kObjectManagerInterfacesRemoved,
 190       base::Bind(&ObjectManager::InterfacesRemovedReceived,
 191                  weak_ptr_factory_.GetWeakPtr()),
 192       base::Bind(&ObjectManager::InterfacesRemovedConnected,
 193                  weak_ptr_factory_.GetWeakPtr()));
 194
 195   GetManagedObjects();
 196 }
 197
 198 bool ObjectManager::SetupMatchRuleAndFilter() {
 199   DCHECK(bus_);
 200   DCHECK(!setup_success_);
 201   bus_->AssertOnDBusThread();
 202
 203   if (cleanup_called_)
 204     return false;
 205
 206   if (!bus_->Connect() || !bus_->SetUpAsyncOperations())
 207     return false;
 208
 209   service_name_owner_ =
 210       bus_->GetServiceOwnerAndBlock(service_name_, Bus::SUPPRESS_ERRORS);
 211
 212   const std::string match_rule =
 213       base::StringPrintf(
 214           "type='signal', sender='%s', interface='%s', member='%s'",
 215           service_name_.c_str(),
 216           kPropertiesInterface,
 217           kPropertiesChanged);
 218
 219   if (!bus_->AddFilterFunction(&ObjectManager::HandleMessageThunk, this)) {
 220     LOG(ERROR) << "ObjectManager failed to add filter function";
 221     return false;
 222   }
 223
 224   ScopedDBusError error;
 225   bus_->AddMatch(match_rule, error.get());
 226   if (error.is_set()) {
 227     LOG(ERROR) << "ObjectManager failed to add match rule \"" << match_rule
 228                << "\". Got " << error.name() << ": " << error.message();
 229     bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
 230     return false;
 231   }
 232
 233   match_rule_ = match_rule;
 234   setup_success_ = true;
 235
 236   return true;
 237 }
 238
 239 void ObjectManager::OnSetupMatchRuleAndFilterComplete(bool success) {
 240   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 241                             << ": Failed to set up match rule.";
 242   if (success)
 243     InitializeObjects();
 244 }
 245
 246 // static
 247 DBusHandlerResult ObjectManager::HandleMessageThunk(DBusConnection* connection,
 248                                                     DBusMessage* raw_message,
 249                                                     void* user_data) {
 250   ObjectManager* self = reinterpret_cast<ObjectManager*>(user_data);
 251   return self->HandleMessage(connection, raw_message);
 252 }
 253
 254 DBusHandlerResult ObjectManager::HandleMessage(DBusConnection* connection,
 255                                                DBusMessage* raw_message) {
 256   DCHECK(bus_);
 257   bus_->AssertOnDBusThread();
 258
 259   if (dbus_message_get_type(raw_message) != DBUS_MESSAGE_TYPE_SIGNAL)
 260     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 261
 262   // raw_message will be unrefed on exit of the function. Increment the
 263   // reference so we can use it in Signal.
 264   dbus_message_ref(raw_message);
 265   scoped_ptr<Signal> signal(
 266       Signal::FromRawMessage(raw_message));
 267
 268   const std::string interface = signal->GetInterface();
 269   const std::string member = signal->GetMember();
 270
 271   statistics::AddReceivedSignal(service_name_, interface, member);
 272
 273   // Only handle the PropertiesChanged signal.
 274   const std::string absolute_signal_name =
 275       GetAbsoluteMemberName(interface, member);
 276   const std::string properties_changed_signal_name =
 277       GetAbsoluteMemberName(kPropertiesInterface, kPropertiesChanged);
 278   if (absolute_signal_name != properties_changed_signal_name)
 279     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 280
 281   VLOG(1) << "Signal received: " << signal->ToString();
 282
 283   // Make sure that the signal originated from the correct sender.
 284   std::string sender = signal->GetSender();
 285   if (service_name_owner_ != sender) {
 286     LOG(ERROR) << "Rejecting a message from a wrong sender.";
 287     UMA_HISTOGRAM_COUNTS("DBus.RejectedSignalCount", 1);
 288     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 289   }
 290
 291   const ObjectPath path = signal->GetPath();
 292
 293   if (bus_->HasDBusThread()) {
 294     // Post a task to run the method in the origin thread. Transfer ownership of
 295     // |signal| to NotifyPropertiesChanged, which will handle the clean up.
 296     Signal* released_signal = signal.release();
 297     bus_->GetOriginTaskRunner()->PostTask(
 298         FROM_HERE,
 299         base::Bind(&ObjectManager::NotifyPropertiesChanged,
 300                    this, path,
 301                    released_signal));
 302   } else {
 303     // If the D-Bus thread is not used, just call the callback on the
 304     // current thread. Transfer the ownership of |signal| to
 305     // NotifyPropertiesChanged.
 306     NotifyPropertiesChanged(path, signal.release());
 307   }
 308
 309   // We don't return DBUS_HANDLER_RESULT_HANDLED for signals because other
 310   // objects may be interested in them. (e.g. Signals from org.freedesktop.DBus)
 311   return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 312 }
 313
 314 void ObjectManager::NotifyPropertiesChanged(
 315     const dbus::ObjectPath object_path,
 316     Signal* signal) {
 317   DCHECK(bus_);
 318   bus_->AssertOnOriginThread();
 319
 320   NotifyPropertiesChangedHelper(object_path, signal);
 321
 322   // Delete the message on the D-Bus thread. See comments in HandleMessage.
 323   bus_->GetDBusTaskRunner()->PostTask(
 324       FROM_HERE,
 325       base::Bind(&base::DeletePointer<Signal>, signal));
 326 }
 327
 328 void ObjectManager::NotifyPropertiesChangedHelper(
 329     const dbus::ObjectPath object_path,
 330     Signal* signal) {
 331   DCHECK(bus_);
 332   bus_->AssertOnOriginThread();
 333
 334   MessageReader reader(signal);
 335   std::string interface;
 336   if (!reader.PopString(&interface)) {
 337     LOG(WARNING) << "Property changed signal has wrong parameters: "
 338                  << "expected interface name: " << signal->ToString();
 339     return;
 340   }
 341
 342   PropertySet* properties = GetProperties(object_path, interface);
 343   if (properties)
 344     properties->ChangedReceived(signal);
 345 }
 346
 347 void ObjectManager::OnGetManagedObjects(Response* response) {
 348   if (response != NULL) {
 349     MessageReader reader(response);
 350     MessageReader array_reader(NULL);
 351     if (!reader.PopArray(&array_reader))
 352       return;
 353
 354     while (array_reader.HasMoreData()) {
 355       MessageReader dict_entry_reader(NULL);
 356       ObjectPath object_path;
 357       if (!array_reader.PopDictEntry(&dict_entry_reader) ||
 358           !dict_entry_reader.PopObjectPath(&object_path))
 359         continue;
 360
 361       UpdateObject(object_path, &dict_entry_reader);
 362     }
 363
 364   } else {
 365     LOG(WARNING) << service_name_ << " " << object_path_.value()
 366                  << ": Failed to get managed objects";
 367   }
 368 }
 369
 370 void ObjectManager::InterfacesAddedReceived(Signal* signal) {
 371   DCHECK(signal);
 372   MessageReader reader(signal);
 373   ObjectPath object_path;
 374   if (!reader.PopObjectPath(&object_path)) {
 375     LOG(WARNING) << service_name_ << " " << object_path_.value()
 376                  << ": InterfacesAdded signal has incorrect parameters: "
 377                  << signal->ToString();
 378     return;
 379   }
 380
 381   UpdateObject(object_path, &reader);
 382 }
 383
 384 void ObjectManager::InterfacesAddedConnected(const std::string& interface_name,
 385                                              const std::string& signal_name,
 386                                              bool success) {
 387   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 388                             << ": Failed to connect to InterfacesAdded signal.";
 389 }
 390
 391 void ObjectManager::InterfacesRemovedReceived(Signal* signal) {
 392   DCHECK(signal);
 393   MessageReader reader(signal);
 394   ObjectPath object_path;
 395   std::vector<std::string> interface_names;
 396   if (!reader.PopObjectPath(&object_path) ||
 397       !reader.PopArrayOfStrings(&interface_names)) {
 398     LOG(WARNING) << service_name_ << " " << object_path_.value()
 399                  << ": InterfacesRemoved signal has incorrect parameters: "
 400                  << signal->ToString();
 401     return;
 402   }
 403
 404   for (size_t i = 0; i < interface_names.size(); ++i)
 405     RemoveInterface(object_path, interface_names[i]);
 406 }
 407
 408 void ObjectManager::InterfacesRemovedConnected(
 409     const std::string& interface_name,
 410     const std::string& signal_name,
 411     bool success) {
 412   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 413                             << ": Failed to connect to "
 414                             << "InterfacesRemoved signal.";
 415 }
 416
 417 void ObjectManager::UpdateObject(const ObjectPath& object_path,
 418                                  MessageReader* reader) {
 419   DCHECK(reader);
 420   MessageReader array_reader(NULL);
 421   if (!reader->PopArray(&array_reader))
 422     return;
 423
 424   while (array_reader.HasMoreData()) {
 425     MessageReader dict_entry_reader(NULL);
 426     std::string interface_name;
 427     if (!array_reader.PopDictEntry(&dict_entry_reader) ||
 428         !dict_entry_reader.PopString(&interface_name))
 429       continue;
 430
 431     AddInterface(object_path, interface_name, &dict_entry_reader);
 432   }
 433 }
 434
 435
 436 void ObjectManager::AddInterface(const ObjectPath& object_path,
 437                                  const std::string& interface_name,
 438                                  MessageReader* reader) {
 439   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
 440   if (iiter == interface_map_.end())
 441     return;
 442   Interface* interface = iiter->second;
 443
 444   ObjectMap::iterator oiter = object_map_.find(object_path);
 445   Object* object;
 446   if (oiter == object_map_.end()) {
 447     object = object_map_[object_path] = new Object;
 448     object->object_proxy = bus_->GetObjectProxy(service_name_, object_path);
 449   } else
 450     object = oiter->second;
 451
 452   Object::PropertiesMap::iterator piter =
 453       object->properties_map.find(interface_name);
 454   PropertySet* property_set;
 455   const bool interface_added = (piter == object->properties_map.end());
 456   if (interface_added) {
 457     property_set = object->properties_map[interface_name] =
 458         interface->CreateProperties(object->object_proxy,
 459                                     object_path, interface_name);
 460   } else
 461     property_set = piter->second;
 462
 463   property_set->UpdatePropertiesFromReader(reader);
 464
 465   if (interface_added)
 466     interface->ObjectAdded(object_path, interface_name);
 467 }
 468
 469 void ObjectManager::RemoveInterface(const ObjectPath& object_path,
 470                                     const std::string& interface_name) {
 471   ObjectMap::iterator oiter = object_map_.find(object_path);
 472   if (oiter == object_map_.end())
 473     return;
 474   Object* object = oiter->second;
 475
 476   Object::PropertiesMap::iterator piter =
 477       object->properties_map.find(interface_name);
 478   if (piter == object->properties_map.end())
 479     return;
 480
 481   // Inform the interface before removing the properties structure or object
 482   // in case it needs details from them to make its own decisions.
 483   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
 484   if (iiter != interface_map_.end()) {
 485     Interface* interface = iiter->second;
 486     interface->ObjectRemoved(object_path, interface_name);
 487   }
 488
 489   object->properties_map.erase(piter);
 490
 491   if (object->properties_map.empty()) {
 492     object_map_.erase(oiter);
 493     delete object;
 494   }
 495 }
 496
 497 void ObjectManager::NameOwnerChanged(const std::string& old_owner,
 498                                      const std::string& new_owner) {
 499   service_name_owner_ = new_owner;
 500
 501   if (!old_owner.empty()) {
 502     ObjectMap::iterator iter = object_map_.begin();
 503     while (iter != object_map_.end()) {
 504       ObjectMap::iterator tmp = iter;
 505       ++iter;
 506
 507       // PropertiesMap is mutated by RemoveInterface, and also Object is
 508       // destroyed; easier to collect the object path and interface names
 509       // and remove them safely.
 510       const dbus::ObjectPath object_path = tmp->first;
 511       Object* object = tmp->second;
 512       std::vector<std::string> interfaces;
 513
 514       for (Object::PropertiesMap::iterator piter =
 515               object->properties_map.begin();
 516            piter != object->properties_map.end(); ++piter)
 517         interfaces.push_back(piter->first);
 518
 519       for (std::vector<std::string>::iterator iiter = interfaces.begin();
 520            iiter != interfaces.end(); ++iiter)
 521         RemoveInterface(object_path, *iiter);
 522     }
 523
 524   }
 525
 526   if (!new_owner.empty())
 527     GetManagedObjects();
 528 }
 529
 530 }  // namespace dbus