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   bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
 159
 160   ScopedDBusError error;
 161   bus_->RemoveMatch(match_rule_, error.get());
 162   if (error.is_set())
 163     LOG(ERROR) << "Failed to remove match rule: " << match_rule_;
 164
 165   match_rule_.clear();
 166 }
 167
 168 void ObjectManager::InitializeObjects() {
 169   DCHECK(bus_);
 170   DCHECK(object_proxy_);
 171   DCHECK(setup_success_);
 172
 173   // |object_proxy_| is no longer valid if the Bus was shut down before this
 174   // call. Don't initiate any other action from the origin thread.
 175   if (cleanup_called_)
 176     return;
 177
 178   object_proxy_->ConnectToSignal(
 179       kObjectManagerInterface,
 180       kObjectManagerInterfacesAdded,
 181       base::Bind(&ObjectManager::InterfacesAddedReceived,
 182                  weak_ptr_factory_.GetWeakPtr()),
 183       base::Bind(&ObjectManager::InterfacesAddedConnected,
 184                  weak_ptr_factory_.GetWeakPtr()));
 185
 186   object_proxy_->ConnectToSignal(
 187       kObjectManagerInterface,
 188       kObjectManagerInterfacesRemoved,
 189       base::Bind(&ObjectManager::InterfacesRemovedReceived,
 190                  weak_ptr_factory_.GetWeakPtr()),
 191       base::Bind(&ObjectManager::InterfacesRemovedConnected,
 192                  weak_ptr_factory_.GetWeakPtr()));
 193
 194   GetManagedObjects();
 195 }
 196
 197 bool ObjectManager::SetupMatchRuleAndFilter() {
 198   DCHECK(bus_);
 199   DCHECK(!setup_success_);
 200   bus_->AssertOnDBusThread();
 201
 202   if (cleanup_called_)
 203     return false;
 204
 205   if (!bus_->Connect() || !bus_->SetUpAsyncOperations())
 206     return false;
 207
 208   service_name_owner_ =
 209       bus_->GetServiceOwnerAndBlock(service_name_, Bus::SUPPRESS_ERRORS);
 210
 211   const std::string match_rule =
 212       base::StringPrintf(
 213           "type='signal', sender='%s', interface='%s', member='%s'",
 214           service_name_.c_str(),
 215           kPropertiesInterface,
 216           kPropertiesChanged);
 217
 218   bus_->AddFilterFunction(&ObjectManager::HandleMessageThunk, this);
 219
 220   ScopedDBusError error;
 221   bus_->AddMatch(match_rule, error.get());
 222   if (error.is_set()) {
 223     LOG(ERROR) << "ObjectManager failed to add match rule \"" << match_rule
 224                << "\". Got " << error.name() << ": " << error.message();
 225     bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
 226     return false;
 227   }
 228
 229   match_rule_ = match_rule;
 230   setup_success_ = true;
 231
 232   return true;
 233 }
 234
 235 void ObjectManager::OnSetupMatchRuleAndFilterComplete(bool success) {
 236   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 237                             << ": Failed to set up match rule.";
 238   if (success)
 239     InitializeObjects();
 240 }
 241
 242 // static
 243 DBusHandlerResult ObjectManager::HandleMessageThunk(DBusConnection* connection,
 244                                                     DBusMessage* raw_message,
 245                                                     void* user_data) {
 246   ObjectManager* self = reinterpret_cast<ObjectManager*>(user_data);
 247   return self->HandleMessage(connection, raw_message);
 248 }
 249
 250 DBusHandlerResult ObjectManager::HandleMessage(DBusConnection* connection,
 251                                                DBusMessage* raw_message) {
 252   DCHECK(bus_);
 253   bus_->AssertOnDBusThread();
 254
 255   if (dbus_message_get_type(raw_message) != DBUS_MESSAGE_TYPE_SIGNAL)
 256     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 257
 258   // raw_message will be unrefed on exit of the function. Increment the
 259   // reference so we can use it in Signal.
 260   dbus_message_ref(raw_message);
 261   scoped_ptr<Signal> signal(
 262       Signal::FromRawMessage(raw_message));
 263
 264   const std::string interface = signal->GetInterface();
 265   const std::string member = signal->GetMember();
 266
 267   statistics::AddReceivedSignal(service_name_, interface, member);
 268
 269   // Only handle the PropertiesChanged signal.
 270   const std::string absolute_signal_name =
 271       GetAbsoluteMemberName(interface, member);
 272   const std::string properties_changed_signal_name =
 273       GetAbsoluteMemberName(kPropertiesInterface, kPropertiesChanged);
 274   if (absolute_signal_name != properties_changed_signal_name)
 275     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 276
 277   VLOG(1) << "Signal received: " << signal->ToString();
 278
 279   // Make sure that the signal originated from the correct sender.
 280   std::string sender = signal->GetSender();
 281   if (service_name_owner_ != sender) {
 282     LOG(ERROR) << "Rejecting a message from a wrong sender.";
 283     UMA_HISTOGRAM_COUNTS("DBus.RejectedSignalCount", 1);
 284     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 285   }
 286
 287   const ObjectPath path = signal->GetPath();
 288
 289   if (bus_->HasDBusThread()) {
 290     // Post a task to run the method in the origin thread. Transfer ownership of
 291     // |signal| to NotifyPropertiesChanged, which will handle the clean up.
 292     Signal* released_signal = signal.release();
 293     bus_->GetOriginTaskRunner()->PostTask(
 294         FROM_HERE,
 295         base::Bind(&ObjectManager::NotifyPropertiesChanged,
 296                    this, path,
 297                    released_signal));
 298   } else {
 299     // If the D-Bus thread is not used, just call the callback on the
 300     // current thread. Transfer the ownership of |signal| to
 301     // NotifyPropertiesChanged.
 302     NotifyPropertiesChanged(path, signal.release());
 303   }
 304
 305   // We don't return DBUS_HANDLER_RESULT_HANDLED for signals because other
 306   // objects may be interested in them. (e.g. Signals from org.freedesktop.DBus)
 307   return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 308 }
 309
 310 void ObjectManager::NotifyPropertiesChanged(
 311     const dbus::ObjectPath object_path,
 312     Signal* signal) {
 313   DCHECK(bus_);
 314   bus_->AssertOnOriginThread();
 315
 316   NotifyPropertiesChangedHelper(object_path, signal);
 317
 318   // Delete the message on the D-Bus thread. See comments in HandleMessage.
 319   bus_->GetDBusTaskRunner()->PostTask(
 320       FROM_HERE,
 321       base::Bind(&base::DeletePointer<Signal>, signal));
 322 }
 323
 324 void ObjectManager::NotifyPropertiesChangedHelper(
 325     const dbus::ObjectPath object_path,
 326     Signal* signal) {
 327   DCHECK(bus_);
 328   bus_->AssertOnOriginThread();
 329
 330   MessageReader reader(signal);
 331   std::string interface;
 332   if (!reader.PopString(&interface)) {
 333     LOG(WARNING) << "Property changed signal has wrong parameters: "
 334                  << "expected interface name: " << signal->ToString();
 335     return;
 336   }
 337
 338   PropertySet* properties = GetProperties(object_path, interface);
 339   if (properties)
 340     properties->ChangedReceived(signal);
 341 }
 342
 343 void ObjectManager::OnGetManagedObjects(Response* response) {
 344   if (response != NULL) {
 345     MessageReader reader(response);
 346     MessageReader array_reader(NULL);
 347     if (!reader.PopArray(&array_reader))
 348       return;
 349
 350     while (array_reader.HasMoreData()) {
 351       MessageReader dict_entry_reader(NULL);
 352       ObjectPath object_path;
 353       if (!array_reader.PopDictEntry(&dict_entry_reader) ||
 354           !dict_entry_reader.PopObjectPath(&object_path))
 355         continue;
 356
 357       UpdateObject(object_path, &dict_entry_reader);
 358     }
 359
 360   } else {
 361     LOG(WARNING) << service_name_ << " " << object_path_.value()
 362                  << ": Failed to get managed objects";
 363   }
 364 }
 365
 366 void ObjectManager::InterfacesAddedReceived(Signal* signal) {
 367   DCHECK(signal);
 368   MessageReader reader(signal);
 369   ObjectPath object_path;
 370   if (!reader.PopObjectPath(&object_path)) {
 371     LOG(WARNING) << service_name_ << " " << object_path_.value()
 372                  << ": InterfacesAdded signal has incorrect parameters: "
 373                  << signal->ToString();
 374     return;
 375   }
 376
 377   UpdateObject(object_path, &reader);
 378 }
 379
 380 void ObjectManager::InterfacesAddedConnected(const std::string& interface_name,
 381                                              const std::string& signal_name,
 382                                              bool success) {
 383   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 384                             << ": Failed to connect to InterfacesAdded signal.";
 385 }
 386
 387 void ObjectManager::InterfacesRemovedReceived(Signal* signal) {
 388   DCHECK(signal);
 389   MessageReader reader(signal);
 390   ObjectPath object_path;
 391   std::vector<std::string> interface_names;
 392   if (!reader.PopObjectPath(&object_path) ||
 393       !reader.PopArrayOfStrings(&interface_names)) {
 394     LOG(WARNING) << service_name_ << " " << object_path_.value()
 395                  << ": InterfacesRemoved signal has incorrect parameters: "
 396                  << signal->ToString();
 397     return;
 398   }
 399
 400   for (size_t i = 0; i < interface_names.size(); ++i)
 401     RemoveInterface(object_path, interface_names[i]);
 402 }
 403
 404 void ObjectManager::InterfacesRemovedConnected(
 405     const std::string& interface_name,
 406     const std::string& signal_name,
 407     bool success) {
 408   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
 409                             << ": Failed to connect to "
 410                             << "InterfacesRemoved signal.";
 411 }
 412
 413 void ObjectManager::UpdateObject(const ObjectPath& object_path,
 414                                  MessageReader* reader) {
 415   DCHECK(reader);
 416   MessageReader array_reader(NULL);
 417   if (!reader->PopArray(&array_reader))
 418     return;
 419
 420   while (array_reader.HasMoreData()) {
 421     MessageReader dict_entry_reader(NULL);
 422     std::string interface_name;
 423     if (!array_reader.PopDictEntry(&dict_entry_reader) ||
 424         !dict_entry_reader.PopString(&interface_name))
 425       continue;
 426
 427     AddInterface(object_path, interface_name, &dict_entry_reader);
 428   }
 429 }
 430
 431
 432 void ObjectManager::AddInterface(const ObjectPath& object_path,
 433                                  const std::string& interface_name,
 434                                  MessageReader* reader) {
 435   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
 436   if (iiter == interface_map_.end())
 437     return;
 438   Interface* interface = iiter->second;
 439
 440   ObjectMap::iterator oiter = object_map_.find(object_path);
 441   Object* object;
 442   if (oiter == object_map_.end()) {
 443     object = object_map_[object_path] = new Object;
 444     object->object_proxy = bus_->GetObjectProxy(service_name_, object_path);
 445   } else
 446     object = oiter->second;
 447
 448   Object::PropertiesMap::iterator piter =
 449       object->properties_map.find(interface_name);
 450   PropertySet* property_set;
 451   const bool interface_added = (piter == object->properties_map.end());
 452   if (interface_added) {
 453     property_set = object->properties_map[interface_name] =
 454         interface->CreateProperties(object->object_proxy,
 455                                     object_path, interface_name);
 456   } else
 457     property_set = piter->second;
 458
 459   property_set->UpdatePropertiesFromReader(reader);
 460
 461   if (interface_added)
 462     interface->ObjectAdded(object_path, interface_name);
 463 }
 464
 465 void ObjectManager::RemoveInterface(const ObjectPath& object_path,
 466                                     const std::string& interface_name) {
 467   ObjectMap::iterator oiter = object_map_.find(object_path);
 468   if (oiter == object_map_.end())
 469     return;
 470   Object* object = oiter->second;
 471
 472   Object::PropertiesMap::iterator piter =
 473       object->properties_map.find(interface_name);
 474   if (piter == object->properties_map.end())
 475     return;
 476
 477   // Inform the interface before removing the properties structure or object
 478   // in case it needs details from them to make its own decisions.
 479   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
 480   if (iiter != interface_map_.end()) {
 481     Interface* interface = iiter->second;
 482     interface->ObjectRemoved(object_path, interface_name);
 483   }
 484
 485   delete piter->second;
 486   object->properties_map.erase(piter);
 487
 488   if (object->properties_map.empty()) {
 489     object_map_.erase(oiter);
 490     delete object;
 491   }
 492 }
 493
 494 void ObjectManager::NameOwnerChanged(const std::string& old_owner,
 495                                      const std::string& new_owner) {
 496   service_name_owner_ = new_owner;
 497
 498   if (!old_owner.empty()) {
 499     ObjectMap::iterator iter = object_map_.begin();
 500     while (iter != object_map_.end()) {
 501       ObjectMap::iterator tmp = iter;
 502       ++iter;
 503
 504       // PropertiesMap is mutated by RemoveInterface, and also Object is
 505       // destroyed; easier to collect the object path and interface names
 506       // and remove them safely.
 507       const dbus::ObjectPath object_path = tmp->first;
 508       Object* object = tmp->second;
 509       std::vector<std::string> interfaces;
 510
 511       for (Object::PropertiesMap::iterator piter =
 512               object->properties_map.begin();
 513            piter != object->properties_map.end(); ++piter)
 514         interfaces.push_back(piter->first);
 515
 516       for (std::vector<std::string>::iterator iiter = interfaces.begin();
 517            iiter != interfaces.end(); ++iiter)
 518         RemoveInterface(object_path, *iiter);
 519     }
 520
 521   }
 522
 523   if (!new_owner.empty())
 524     GetManagedObjects();
 525 }
 526
 527 }  // namespace dbus