dbus/object_manager.cc - chromium/src - Git at Google

 // Copyright 2013 The Chromium Authors
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "dbus/object_manager.h"

 #include <stddef.h>

 #include "base/functional/bind.h"
 #include "base/functional/callback_helpers.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/stringprintf.h"
 #include "dbus/bus.h"
 #include "dbus/dbus_statistics.h"
 #include "dbus/error.h"
 #include "dbus/message.h"
 #include "dbus/object_proxy.h"
 #include "dbus/property.h"
 #include "dbus/util.h"

 namespace dbus {

 ObjectManager::Object::Object()
   : object_proxy(nullptr) {
 }

 ObjectManager::Object::~Object() = default;

 scoped_refptr<ObjectManager> ObjectManager::Create(
     Bus* bus,
     const std::string& service_name,
     const ObjectPath& object_path) {
   auto object_manager =
       base::WrapRefCounted(new ObjectManager(bus, service_name, object_path));

   // Set up a match rule and a filter function to handle PropertiesChanged
   // signals from the service. This is important to avoid any race conditions
   // that might cause us to miss PropertiesChanged signals once all objects are
   // initialized via GetManagedObjects.
   bus->GetDBusTaskRunner()->PostTaskAndReplyWithResult(
       FROM_HERE,
       base::BindOnce(&ObjectManager::SetupMatchRuleAndFilter, object_manager),
       base::BindOnce(&ObjectManager::OnSetupMatchRuleAndFilterComplete,
                      object_manager));
   return object_manager;
 }

 ObjectManager::ObjectManager(Bus* bus,
                              const std::string& service_name,
                              const ObjectPath& object_path)
     : bus_(bus), service_name_(service_name), object_path_(object_path) {
   LOG_IF(FATAL, !object_path_.IsValid()) << object_path_.value();
   DVLOG(1) << "Creating ObjectManager for " << service_name_
            << " " << object_path_.value();
   DCHECK(bus_);
   bus_->AssertOnOriginThread();
   object_proxy_ = bus_->GetObjectProxy(service_name_, object_path_);
   object_proxy_->SetNameOwnerChangedCallback(base::BindRepeating(
       &ObjectManager::NameOwnerChanged, weak_ptr_factory_.GetWeakPtr()));
 }

 ObjectManager::~ObjectManager() {
   // Clean up Object structures
   for (ObjectMap::iterator iter = object_map_.begin();
        iter != object_map_.end(); ++iter) {
     Object* object = iter->second;

     for (Object::PropertiesMap::iterator piter = object->properties_map.begin();
          piter != object->properties_map.end(); ++piter) {
       PropertySet* properties = piter->second;
       delete properties;
     }

     delete object;
   }
 }

 void ObjectManager::RegisterInterface(const std::string& interface_name,
                                       Interface* interface) {
   interface_map_[interface_name] = interface;
 }

 void ObjectManager::UnregisterInterface(const std::string& interface_name) {
   InterfaceMap::iterator iter = interface_map_.find(interface_name);
   if (iter != interface_map_.end())
     interface_map_.erase(iter);
 }

 bool ObjectManager::IsInterfaceRegisteredForTesting(
     const std::string& interface_name) const {
   return interface_map_.count(interface_name);
 }

 std::vector<ObjectPath> ObjectManager::GetObjects() {
   std::vector<ObjectPath> object_paths;

   for (ObjectMap::iterator iter = object_map_.begin();
        iter != object_map_.end(); ++iter)
     object_paths.push_back(iter->first);

   return object_paths;
 }

 std::vector<ObjectPath> ObjectManager::GetObjectsWithInterface(
       const std::string& interface_name) {
   std::vector<ObjectPath> object_paths;

   for (ObjectMap::iterator oiter = object_map_.begin();
        oiter != object_map_.end(); ++oiter) {
     Object* object = oiter->second;

     Object::PropertiesMap::iterator piter =
         object->properties_map.find(interface_name);
     if (piter != object->properties_map.end())
       object_paths.push_back(oiter->first);
   }

   return object_paths;
 }

 ObjectProxy* ObjectManager::GetObjectProxy(const ObjectPath& object_path) {
   ObjectMap::iterator iter = object_map_.find(object_path);
   if (iter == object_map_.end())
     return nullptr;

   Object* object = iter->second;
   return object->object_proxy;
 }

 PropertySet* ObjectManager::GetProperties(const ObjectPath& object_path,
                                           const std::string& interface_name) {
   ObjectMap::iterator iter = object_map_.find(object_path);
   if (iter == object_map_.end())
     return nullptr;

   Object* object = iter->second;
   Object::PropertiesMap::iterator piter =
       object->properties_map.find(interface_name);
   if (piter == object->properties_map.end())
     return nullptr;

   return piter->second;
 }

 void ObjectManager::GetManagedObjects() {
   MethodCall method_call(kObjectManagerInterface,
                          kObjectManagerGetManagedObjects);

   object_proxy_->CallMethod(&method_call, ObjectProxy::TIMEOUT_USE_DEFAULT,
                             base::BindOnce(&ObjectManager::OnGetManagedObjects,
                                            weak_ptr_factory_.GetWeakPtr()));
 }

 void ObjectManager::CleanUp() {
   DCHECK(bus_);
   bus_->AssertOnDBusThread();
   DCHECK(!cleanup_called_);

   cleanup_called_ = true;

   if (!setup_success_)
     return;

   bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
   Error error;
   bus_->RemoveMatch(match_rule_, &error);
   if (error.IsValid()) {
     LOG(ERROR) << "Failed to remove match rule: " << match_rule_;
   }

   match_rule_.clear();
   // After Cleanup(), the Bus doesn't own `this` anymore and might be deleted
   // before `this`.
   bus_ = nullptr;
 }

 bool ObjectManager::SetupMatchRuleAndFilter() {
   DCHECK(!setup_success_);

   if (cleanup_called_) {
     return false;
   }

   DCHECK(bus_);
   bus_->AssertOnDBusThread();

   if (!bus_->Connect() || !bus_->SetUpAsyncOperations())
     return false;

   // Try to get |service_name_owner_| from dbus if we haven't received any
   // NameOwnerChanged signals.
   if (service_name_owner_.empty()) {
     service_name_owner_ =
         bus_->GetServiceOwnerAndBlock(service_name_, Bus::SUPPRESS_ERRORS);
   }

   const std::string match_rule =
       base::StringPrintf(
           "type='signal', sender='%s', interface='%s', member='%s'",
           service_name_.c_str(),
           kPropertiesInterface,
           kPropertiesChanged);

   bus_->AddFilterFunction(&ObjectManager::HandleMessageThunk, this);

   Error error;
   bus_->AddMatch(match_rule, &error);
   if (error.IsValid()) {
     LOG(ERROR) << "ObjectManager failed to add match rule \"" << match_rule
                << "\". Got " << error.name() << ": " << error.message();
     bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
     return false;
   }

   match_rule_ = match_rule;
   setup_success_ = true;

   return true;
 }

 void ObjectManager::OnSetupMatchRuleAndFilterComplete(bool success) {
   if (!success) {
     LOG(WARNING) << service_name_ << " " << object_path_.value()
                  << ": Failed to set up match rule.";
     return;
   }
   DCHECK(object_proxy_);
   DCHECK(setup_success_);

   // |object_proxy_| is no longer valid if the Bus was shut down before this
   // call. Don't initiate any other action from the origin thread.
   if (cleanup_called_) {
     return;
   }

   DCHECK(bus_);
   bus_->AssertOnOriginThread();

   object_proxy_->ConnectToSignal(
       kObjectManagerInterface, kObjectManagerInterfacesAdded,
       base::BindRepeating(&ObjectManager::InterfacesAddedReceived,
                           weak_ptr_factory_.GetWeakPtr()),
       base::BindOnce(&ObjectManager::InterfacesAddedConnected,
                      weak_ptr_factory_.GetWeakPtr()));

   object_proxy_->ConnectToSignal(
       kObjectManagerInterface, kObjectManagerInterfacesRemoved,
       base::BindRepeating(&ObjectManager::InterfacesRemovedReceived,
                           weak_ptr_factory_.GetWeakPtr()),
       base::BindOnce(&ObjectManager::InterfacesRemovedConnected,
                      weak_ptr_factory_.GetWeakPtr()));

   if (!service_name_owner_.empty())
     GetManagedObjects();
 }

 // static
 DBusHandlerResult ObjectManager::HandleMessageThunk(DBusConnection* connection,
                                                     DBusMessage* raw_message,
                                                     void* user_data) {
   ObjectManager* self = reinterpret_cast<ObjectManager*>(user_data);
   return self->HandleMessage(connection, raw_message);
 }

 DBusHandlerResult ObjectManager::HandleMessage(DBusConnection* connection,
                                                DBusMessage* raw_message) {
   DCHECK(bus_);
   bus_->AssertOnDBusThread();

   // Handle the message only if it is a signal.
   // Note that the match rule in SetupMatchRuleAndFilter() is configured to
   // only accept signals, but we check here just in case.
   if (dbus_message_get_type(raw_message) != DBUS_MESSAGE_TYPE_SIGNAL)
     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

   // raw_message will be unrefed on exit of the function. Increment the
   // reference so we can use it in Signal.
   dbus_message_ref(raw_message);
   std::unique_ptr<Signal> signal(Signal::FromRawMessage(raw_message));

   const std::string interface = signal->GetInterface();
   const std::string member = signal->GetMember();

   statistics::AddReceivedSignal(service_name_, interface, member);

   // Handle the signal only if it is PropertiesChanged.
   // Note that the match rule in SetupMatchRuleAndFilter() is configured to
   // only accept PropertiesChanged signals, but we check here just in case.
   const std::string absolute_signal_name =
       GetAbsoluteMemberName(interface, member);
   const std::string properties_changed_signal_name =
       GetAbsoluteMemberName(kPropertiesInterface, kPropertiesChanged);
   if (absolute_signal_name != properties_changed_signal_name)
     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

   VLOG(1) << "Signal received: " << signal->ToString();

   // Handle the signal only if it is from the service that the ObjectManager
   // instance is interested in.
   // Note that the match rule in SetupMatchRuleAndFilter() is configured to
   // only accept messages from the service name of our interest. However, the
   // service='...' filter does not work as intended. See crbug.com/507206#14
   // and #15 for details, hence it's necessary to check the sender here.
   std::string sender = signal->GetSender();
   if (service_name_owner_ != sender)
     return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

   const ObjectPath path = signal->GetPath();

   if (bus_->HasDBusThread()) {
     // Post a task to run the method in the origin thread. Transfer ownership of
     // |signal| to NotifyPropertiesChanged, which will handle the clean up.
     Signal* released_signal = signal.release();
     bus_->GetOriginTaskRunner()->PostTask(
         FROM_HERE, base::BindOnce(&ObjectManager::NotifyPropertiesChanged, this,
                                   path, released_signal));
   } else {
     // If the D-Bus thread is not used, just call the callback on the
     // current thread. Transfer the ownership of |signal| to
     // NotifyPropertiesChanged.
     NotifyPropertiesChanged(path, signal.release());
   }

   // We don't return DBUS_HANDLER_RESULT_HANDLED for signals because other
   // objects may be interested in them. (e.g. Signals from org.freedesktop.DBus)
   return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 }

 void ObjectManager::NotifyPropertiesChanged(
     const dbus::ObjectPath object_path,
     Signal* signal) {
   DCHECK(bus_);
   bus_->AssertOnOriginThread();

   NotifyPropertiesChangedHelper(object_path, signal);

   // Delete the message on the D-Bus thread. See comments in HandleMessage.
   bus_->GetDBusTaskRunner()->PostTask(
       FROM_HERE, base::BindOnce(&base::DeletePointer<Signal>, signal));
 }

 void ObjectManager::NotifyPropertiesChangedHelper(
     const dbus::ObjectPath object_path,
     Signal* signal) {
   DCHECK(bus_);
   bus_->AssertOnOriginThread();

   MessageReader reader(signal);
   std::string interface;
   if (!reader.PopString(&interface)) {
     LOG(WARNING) << "Property changed signal has wrong parameters: "
                  << "expected interface name: " << signal->ToString();
     return;
   }

   PropertySet* properties = GetProperties(object_path, interface);
   if (properties)
     properties->ChangedReceived(signal);
 }

 void ObjectManager::OnGetManagedObjects(Response* response) {
   if (response != nullptr) {
     MessageReader reader(response);
     MessageReader array_reader(nullptr);
     if (!reader.PopArray(&array_reader))
       return;

     while (array_reader.HasMoreData()) {
       MessageReader dict_entry_reader(nullptr);
       ObjectPath object_path;
       if (!array_reader.PopDictEntry(&dict_entry_reader) ||
           !dict_entry_reader.PopObjectPath(&object_path))
         continue;

       UpdateObject(object_path, &dict_entry_reader);
     }

   } else {
     LOG(WARNING) << service_name_ << " " << object_path_.value()
                  << ": Failed to get managed objects";
   }
 }

 void ObjectManager::InterfacesAddedReceived(Signal* signal) {
   DCHECK(signal);
   MessageReader reader(signal);
   ObjectPath object_path;
   if (!reader.PopObjectPath(&object_path)) {
     LOG(WARNING) << service_name_ << " " << object_path_.value()
                  << ": InterfacesAdded signal has incorrect parameters: "
                  << signal->ToString();
     return;
   }

   UpdateObject(object_path, &reader);
 }

 void ObjectManager::InterfacesAddedConnected(const std::string& interface_name,
                                              const std::string& signal_name,
                                              bool success) {
   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
                             << ": Failed to connect to InterfacesAdded signal.";
 }

 void ObjectManager::InterfacesRemovedReceived(Signal* signal) {
   DCHECK(signal);
   MessageReader reader(signal);
   ObjectPath object_path;
   std::vector<std::string> interface_names;
   if (!reader.PopObjectPath(&object_path) ||
       !reader.PopArrayOfStrings(&interface_names)) {
     LOG(WARNING) << service_name_ << " " << object_path_.value()
                  << ": InterfacesRemoved signal has incorrect parameters: "
                  << signal->ToString();
     return;
   }

   for (size_t i = 0; i < interface_names.size(); ++i)
     RemoveInterface(object_path, interface_names[i]);
 }

 void ObjectManager::InterfacesRemovedConnected(
     const std::string& interface_name,
     const std::string& signal_name,
     bool success) {
   LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
                             << ": Failed to connect to "
                             << "InterfacesRemoved signal.";
 }

 void ObjectManager::UpdateObject(const ObjectPath& object_path,
                                  MessageReader* reader) {
   DCHECK(reader);
   MessageReader array_reader(nullptr);
   if (!reader->PopArray(&array_reader))
     return;

   while (array_reader.HasMoreData()) {
     MessageReader dict_entry_reader(nullptr);
     std::string interface_name;
     if (!array_reader.PopDictEntry(&dict_entry_reader) ||
         !dict_entry_reader.PopString(&interface_name))
       continue;

     AddInterface(object_path, interface_name, &dict_entry_reader);
   }
 }


 void ObjectManager::AddInterface(const ObjectPath& object_path,
                                  const std::string& interface_name,
                                  MessageReader* reader) {
   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
   if (iiter == interface_map_.end())
     return;
   Interface* interface = iiter->second;

   ObjectMap::iterator oiter = object_map_.find(object_path);
   Object* object;
   if (oiter == object_map_.end()) {
     object = object_map_[object_path] = new Object;
     object->object_proxy = bus_->GetObjectProxy(service_name_, object_path);
   } else
     object = oiter->second;

   Object::PropertiesMap::iterator piter =
       object->properties_map.find(interface_name);
   PropertySet* property_set;
   const bool interface_added = (piter == object->properties_map.end());
   if (interface_added) {
     property_set = object->properties_map[interface_name] =
         interface->CreateProperties(object->object_proxy,
                                     object_path, interface_name);
   } else
     property_set = piter->second;

   property_set->UpdatePropertiesFromReader(reader);

   if (interface_added)
     interface->ObjectAdded(object_path, interface_name);
 }

 void ObjectManager::RemoveInterface(const ObjectPath& object_path,
                                     const std::string& interface_name) {
   ObjectMap::iterator oiter = object_map_.find(object_path);
   if (oiter == object_map_.end())
     return;
   Object* object = oiter->second;

   Object::PropertiesMap::iterator piter =
       object->properties_map.find(interface_name);
   if (piter == object->properties_map.end())
     return;

   // Inform the interface before removing the properties structure or object
   // in case it needs details from them to make its own decisions.
   InterfaceMap::iterator iiter = interface_map_.find(interface_name);
   if (iiter != interface_map_.end()) {
     Interface* interface = iiter->second;
     interface->ObjectRemoved(object_path, interface_name);
   }

   delete piter->second;
   object->properties_map.erase(piter);

   if (object->properties_map.empty()) {
     object_map_.erase(oiter);
     delete object;
   }
 }

 void ObjectManager::UpdateServiceNameOwner(const std::string& new_owner) {
   bus_->AssertOnDBusThread();
   service_name_owner_ = new_owner;
 }

 void ObjectManager::NameOwnerChanged(const std::string& old_owner,
                                      const std::string& new_owner) {
   bus_->AssertOnOriginThread();

   bus_->GetDBusTaskRunner()->PostTask(
       FROM_HERE,
       base::BindOnce(&ObjectManager::UpdateServiceNameOwner, this, new_owner));

   if (!old_owner.empty()) {
     ObjectMap::iterator iter = object_map_.begin();
     while (iter != object_map_.end()) {
       ObjectMap::iterator tmp = iter;
       ++iter;

       // PropertiesMap is mutated by RemoveInterface, and also Object is
       // destroyed; easier to collect the object path and interface names
       // and remove them safely.
       const dbus::ObjectPath object_path = tmp->first;
       Object* object = tmp->second;
       std::vector<std::string> interfaces;

       for (Object::PropertiesMap::iterator piter =
               object->properties_map.begin();
            piter != object->properties_map.end(); ++piter)
         interfaces.push_back(piter->first);

       for (std::vector<std::string>::iterator iiter = interfaces.begin();
            iiter != interfaces.end(); ++iiter)
         RemoveInterface(object_path, *iiter);
     }

   }

   if (!new_owner.empty())
     GetManagedObjects();
 }

 }  // namespace dbus
	// Copyright 2013 The Chromium Authors
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "dbus/object_manager.h"

	#include <stddef.h>

	#include "base/functional/bind.h"
	#include "base/functional/callback_helpers.h"
	#include "base/location.h"
	#include "base/logging.h"
	#include "base/metrics/histogram.h"
	#include "base/strings/stringprintf.h"
	#include "dbus/bus.h"
	#include "dbus/dbus_statistics.h"
	#include "dbus/error.h"
	#include "dbus/message.h"
	#include "dbus/object_proxy.h"
	#include "dbus/property.h"
	#include "dbus/util.h"

	namespace dbus {

	ObjectManager::Object::Object()
	: object_proxy(nullptr) {
	}

	ObjectManager::Object::~Object() = default;

	scoped_refptr<ObjectManager> ObjectManager::Create(
	Bus* bus,
	const std::string& service_name,
	const ObjectPath& object_path) {
	auto object_manager =
	base::WrapRefCounted(new ObjectManager(bus, service_name, object_path));

	// Set up a match rule and a filter function to handle PropertiesChanged
	// signals from the service. This is important to avoid any race conditions
	// that might cause us to miss PropertiesChanged signals once all objects are
	// initialized via GetManagedObjects.
	bus->GetDBusTaskRunner()->PostTaskAndReplyWithResult(
	FROM_HERE,
	base::BindOnce(&ObjectManager::SetupMatchRuleAndFilter, object_manager),
	base::BindOnce(&ObjectManager::OnSetupMatchRuleAndFilterComplete,
	object_manager));
	return object_manager;
	}

	ObjectManager::ObjectManager(Bus* bus,
	const std::string& service_name,
	const ObjectPath& object_path)
	: bus_(bus), service_name_(service_name), object_path_(object_path) {
	LOG_IF(FATAL, !object_path_.IsValid()) << object_path_.value();
	DVLOG(1) << "Creating ObjectManager for " << service_name_
	<< " " << object_path_.value();
	DCHECK(bus_);
	bus_->AssertOnOriginThread();
	object_proxy_ = bus_->GetObjectProxy(service_name_, object_path_);
	object_proxy_->SetNameOwnerChangedCallback(base::BindRepeating(
	&ObjectManager::NameOwnerChanged, weak_ptr_factory_.GetWeakPtr()));
	}

	ObjectManager::~ObjectManager() {
	// Clean up Object structures
	for (ObjectMap::iterator iter = object_map_.begin();
	iter != object_map_.end(); ++iter) {
	Object* object = iter->second;

	for (Object::PropertiesMap::iterator piter = object->properties_map.begin();
	piter != object->properties_map.end(); ++piter) {
	PropertySet* properties = piter->second;
	delete properties;
	}

	delete object;
	}
	}

	void ObjectManager::RegisterInterface(const std::string& interface_name,
	Interface* interface) {
	interface_map_[interface_name] = interface;
	}

	void ObjectManager::UnregisterInterface(const std::string& interface_name) {
	InterfaceMap::iterator iter = interface_map_.find(interface_name);
	if (iter != interface_map_.end())
	interface_map_.erase(iter);
	}

	bool ObjectManager::IsInterfaceRegisteredForTesting(
	const std::string& interface_name) const {
	return interface_map_.count(interface_name);
	}

	std::vector<ObjectPath> ObjectManager::GetObjects() {
	std::vector<ObjectPath> object_paths;

	for (ObjectMap::iterator iter = object_map_.begin();
	iter != object_map_.end(); ++iter)
	object_paths.push_back(iter->first);

	return object_paths;
	}

	std::vector<ObjectPath> ObjectManager::GetObjectsWithInterface(
	const std::string& interface_name) {
	std::vector<ObjectPath> object_paths;

	for (ObjectMap::iterator oiter = object_map_.begin();
	oiter != object_map_.end(); ++oiter) {
	Object* object = oiter->second;

	Object::PropertiesMap::iterator piter =
	object->properties_map.find(interface_name);
	if (piter != object->properties_map.end())
	object_paths.push_back(oiter->first);
	}

	return object_paths;
	}

	ObjectProxy* ObjectManager::GetObjectProxy(const ObjectPath& object_path) {
	ObjectMap::iterator iter = object_map_.find(object_path);
	if (iter == object_map_.end())
	return nullptr;

	Object* object = iter->second;
	return object->object_proxy;
	}

	PropertySet* ObjectManager::GetProperties(const ObjectPath& object_path,
	const std::string& interface_name) {
	ObjectMap::iterator iter = object_map_.find(object_path);
	if (iter == object_map_.end())
	return nullptr;

	Object* object = iter->second;
	Object::PropertiesMap::iterator piter =
	object->properties_map.find(interface_name);
	if (piter == object->properties_map.end())
	return nullptr;

	return piter->second;
	}

	void ObjectManager::GetManagedObjects() {
	MethodCall method_call(kObjectManagerInterface,
	kObjectManagerGetManagedObjects);

	object_proxy_->CallMethod(&method_call, ObjectProxy::TIMEOUT_USE_DEFAULT,
	base::BindOnce(&ObjectManager::OnGetManagedObjects,
	weak_ptr_factory_.GetWeakPtr()));
	}

	void ObjectManager::CleanUp() {
	DCHECK(bus_);
	bus_->AssertOnDBusThread();
	DCHECK(!cleanup_called_);

	cleanup_called_ = true;

	if (!setup_success_)
	return;

	bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
	Error error;
	bus_->RemoveMatch(match_rule_, &error);
	if (error.IsValid()) {
	LOG(ERROR) << "Failed to remove match rule: " << match_rule_;
	}

	match_rule_.clear();
	// After Cleanup(), the Bus doesn't own `this` anymore and might be deleted
	// before `this`.
	bus_ = nullptr;
	}

	bool ObjectManager::SetupMatchRuleAndFilter() {
	DCHECK(!setup_success_);

	if (cleanup_called_) {
	return false;
	}

	DCHECK(bus_);
	bus_->AssertOnDBusThread();

	if (!bus_->Connect() \|\| !bus_->SetUpAsyncOperations())
	return false;

	// Try to get \|service_name_owner_\| from dbus if we haven't received any
	// NameOwnerChanged signals.
	if (service_name_owner_.empty()) {
	service_name_owner_ =
	bus_->GetServiceOwnerAndBlock(service_name_, Bus::SUPPRESS_ERRORS);
	}

	const std::string match_rule =
	base::StringPrintf(
	"type='signal', sender='%s', interface='%s', member='%s'",
	service_name_.c_str(),
	kPropertiesInterface,
	kPropertiesChanged);

	bus_->AddFilterFunction(&ObjectManager::HandleMessageThunk, this);

	Error error;
	bus_->AddMatch(match_rule, &error);
	if (error.IsValid()) {
	LOG(ERROR) << "ObjectManager failed to add match rule \"" << match_rule
	<< "\". Got " << error.name() << ": " << error.message();
	bus_->RemoveFilterFunction(&ObjectManager::HandleMessageThunk, this);
	return false;
	}

	match_rule_ = match_rule;
	setup_success_ = true;

	return true;
	}

	void ObjectManager::OnSetupMatchRuleAndFilterComplete(bool success) {
	if (!success) {
	LOG(WARNING) << service_name_ << " " << object_path_.value()
	<< ": Failed to set up match rule.";
	return;
	}
	DCHECK(object_proxy_);
	DCHECK(setup_success_);

	// \|object_proxy_\| is no longer valid if the Bus was shut down before this
	// call. Don't initiate any other action from the origin thread.
	if (cleanup_called_) {
	return;
	}

	DCHECK(bus_);
	bus_->AssertOnOriginThread();

	object_proxy_->ConnectToSignal(
	kObjectManagerInterface, kObjectManagerInterfacesAdded,
	base::BindRepeating(&ObjectManager::InterfacesAddedReceived,
	weak_ptr_factory_.GetWeakPtr()),
	base::BindOnce(&ObjectManager::InterfacesAddedConnected,
	weak_ptr_factory_.GetWeakPtr()));

	object_proxy_->ConnectToSignal(
	kObjectManagerInterface, kObjectManagerInterfacesRemoved,
	base::BindRepeating(&ObjectManager::InterfacesRemovedReceived,
	weak_ptr_factory_.GetWeakPtr()),
	base::BindOnce(&ObjectManager::InterfacesRemovedConnected,
	weak_ptr_factory_.GetWeakPtr()));

	if (!service_name_owner_.empty())
	GetManagedObjects();
	}

	// static
	DBusHandlerResult ObjectManager::HandleMessageThunk(DBusConnection* connection,
	DBusMessage* raw_message,
	void* user_data) {
	ObjectManager* self = reinterpret_cast<ObjectManager*>(user_data);
	return self->HandleMessage(connection, raw_message);
	}

	DBusHandlerResult ObjectManager::HandleMessage(DBusConnection* connection,
	DBusMessage* raw_message) {
	DCHECK(bus_);
	bus_->AssertOnDBusThread();

	// Handle the message only if it is a signal.
	// Note that the match rule in SetupMatchRuleAndFilter() is configured to
	// only accept signals, but we check here just in case.
	if (dbus_message_get_type(raw_message) != DBUS_MESSAGE_TYPE_SIGNAL)
	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

	// raw_message will be unrefed on exit of the function. Increment the
	// reference so we can use it in Signal.
	dbus_message_ref(raw_message);
	std::unique_ptr<Signal> signal(Signal::FromRawMessage(raw_message));

	const std::string interface = signal->GetInterface();
	const std::string member = signal->GetMember();

	statistics::AddReceivedSignal(service_name_, interface, member);

	// Handle the signal only if it is PropertiesChanged.
	// Note that the match rule in SetupMatchRuleAndFilter() is configured to
	// only accept PropertiesChanged signals, but we check here just in case.
	const std::string absolute_signal_name =
	GetAbsoluteMemberName(interface, member);
	const std::string properties_changed_signal_name =
	GetAbsoluteMemberName(kPropertiesInterface, kPropertiesChanged);
	if (absolute_signal_name != properties_changed_signal_name)
	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

	VLOG(1) << "Signal received: " << signal->ToString();

	// Handle the signal only if it is from the service that the ObjectManager
	// instance is interested in.
	// Note that the match rule in SetupMatchRuleAndFilter() is configured to
	// only accept messages from the service name of our interest. However, the
	// service='...' filter does not work as intended. See crbug.com/507206#14
	// and #15 for details, hence it's necessary to check the sender here.
	std::string sender = signal->GetSender();
	if (service_name_owner_ != sender)
	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;

	const ObjectPath path = signal->GetPath();

	if (bus_->HasDBusThread()) {
	// Post a task to run the method in the origin thread. Transfer ownership of
	// \|signal\| to NotifyPropertiesChanged, which will handle the clean up.
	Signal* released_signal = signal.release();
	bus_->GetOriginTaskRunner()->PostTask(
	FROM_HERE, base::BindOnce(&ObjectManager::NotifyPropertiesChanged, this,
	path, released_signal));
	} else {
	// If the D-Bus thread is not used, just call the callback on the
	// current thread. Transfer the ownership of \|signal\| to
	// NotifyPropertiesChanged.
	NotifyPropertiesChanged(path, signal.release());
	}

	// We don't return DBUS_HANDLER_RESULT_HANDLED for signals because other
	// objects may be interested in them. (e.g. Signals from org.freedesktop.DBus)
	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}

	void ObjectManager::NotifyPropertiesChanged(
	const dbus::ObjectPath object_path,
	Signal* signal) {
	DCHECK(bus_);
	bus_->AssertOnOriginThread();

	NotifyPropertiesChangedHelper(object_path, signal);

	// Delete the message on the D-Bus thread. See comments in HandleMessage.
	bus_->GetDBusTaskRunner()->PostTask(
	FROM_HERE, base::BindOnce(&base::DeletePointer<Signal>, signal));
	}

	void ObjectManager::NotifyPropertiesChangedHelper(
	const dbus::ObjectPath object_path,
	Signal* signal) {
	DCHECK(bus_);
	bus_->AssertOnOriginThread();

	MessageReader reader(signal);
	std::string interface;
	if (!reader.PopString(&interface)) {
	LOG(WARNING) << "Property changed signal has wrong parameters: "
	<< "expected interface name: " << signal->ToString();
	return;
	}

	PropertySet* properties = GetProperties(object_path, interface);
	if (properties)
	properties->ChangedReceived(signal);
	}

	void ObjectManager::OnGetManagedObjects(Response* response) {
	if (response != nullptr) {
	MessageReader reader(response);
	MessageReader array_reader(nullptr);
	if (!reader.PopArray(&array_reader))
	return;

	while (array_reader.HasMoreData()) {
	MessageReader dict_entry_reader(nullptr);
	ObjectPath object_path;
	if (!array_reader.PopDictEntry(&dict_entry_reader) \|\|
	!dict_entry_reader.PopObjectPath(&object_path))
	continue;

	UpdateObject(object_path, &dict_entry_reader);
	}

	} else {
	LOG(WARNING) << service_name_ << " " << object_path_.value()
	<< ": Failed to get managed objects";
	}
	}

	void ObjectManager::InterfacesAddedReceived(Signal* signal) {
	DCHECK(signal);
	MessageReader reader(signal);
	ObjectPath object_path;
	if (!reader.PopObjectPath(&object_path)) {
	LOG(WARNING) << service_name_ << " " << object_path_.value()
	<< ": InterfacesAdded signal has incorrect parameters: "
	<< signal->ToString();
	return;
	}

	UpdateObject(object_path, &reader);
	}

	void ObjectManager::InterfacesAddedConnected(const std::string& interface_name,
	const std::string& signal_name,
	bool success) {
	LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
	<< ": Failed to connect to InterfacesAdded signal.";
	}

	void ObjectManager::InterfacesRemovedReceived(Signal* signal) {
	DCHECK(signal);
	MessageReader reader(signal);
	ObjectPath object_path;
	std::vector<std::string> interface_names;
	if (!reader.PopObjectPath(&object_path) \|\|
	!reader.PopArrayOfStrings(&interface_names)) {
	LOG(WARNING) << service_name_ << " " << object_path_.value()
	<< ": InterfacesRemoved signal has incorrect parameters: "
	<< signal->ToString();
	return;
	}

	for (size_t i = 0; i < interface_names.size(); ++i)
	RemoveInterface(object_path, interface_names[i]);
	}

	void ObjectManager::InterfacesRemovedConnected(
	const std::string& interface_name,
	const std::string& signal_name,
	bool success) {
	LOG_IF(WARNING, !success) << service_name_ << " " << object_path_.value()
	<< ": Failed to connect to "
	<< "InterfacesRemoved signal.";
	}

	void ObjectManager::UpdateObject(const ObjectPath& object_path,
	MessageReader* reader) {
	DCHECK(reader);
	MessageReader array_reader(nullptr);
	if (!reader->PopArray(&array_reader))
	return;

	while (array_reader.HasMoreData()) {
	MessageReader dict_entry_reader(nullptr);
	std::string interface_name;
	if (!array_reader.PopDictEntry(&dict_entry_reader) \|\|
	!dict_entry_reader.PopString(&interface_name))
	continue;

	AddInterface(object_path, interface_name, &dict_entry_reader);
	}
	}


	void ObjectManager::AddInterface(const ObjectPath& object_path,
	const std::string& interface_name,
	MessageReader* reader) {
	InterfaceMap::iterator iiter = interface_map_.find(interface_name);
	if (iiter == interface_map_.end())
	return;
	Interface* interface = iiter->second;

	ObjectMap::iterator oiter = object_map_.find(object_path);
	Object* object;
	if (oiter == object_map_.end()) {
	object = object_map_[object_path] = new Object;
	object->object_proxy = bus_->GetObjectProxy(service_name_, object_path);
	} else
	object = oiter->second;

	Object::PropertiesMap::iterator piter =
	object->properties_map.find(interface_name);
	PropertySet* property_set;
	const bool interface_added = (piter == object->properties_map.end());
	if (interface_added) {
	property_set = object->properties_map[interface_name] =
	interface->CreateProperties(object->object_proxy,
	object_path, interface_name);
	} else
	property_set = piter->second;

	property_set->UpdatePropertiesFromReader(reader);

	if (interface_added)
	interface->ObjectAdded(object_path, interface_name);
	}

	void ObjectManager::RemoveInterface(const ObjectPath& object_path,
	const std::string& interface_name) {
	ObjectMap::iterator oiter = object_map_.find(object_path);
	if (oiter == object_map_.end())
	return;
	Object* object = oiter->second;

	Object::PropertiesMap::iterator piter =
	object->properties_map.find(interface_name);
	if (piter == object->properties_map.end())
	return;

	// Inform the interface before removing the properties structure or object
	// in case it needs details from them to make its own decisions.
	InterfaceMap::iterator iiter = interface_map_.find(interface_name);
	if (iiter != interface_map_.end()) {
	Interface* interface = iiter->second;
	interface->ObjectRemoved(object_path, interface_name);
	}

	delete piter->second;
	object->properties_map.erase(piter);

	if (object->properties_map.empty()) {
	object_map_.erase(oiter);
	delete object;
	}
	}

	void ObjectManager::UpdateServiceNameOwner(const std::string& new_owner) {
	bus_->AssertOnDBusThread();
	service_name_owner_ = new_owner;
	}

	void ObjectManager::NameOwnerChanged(const std::string& old_owner,
	const std::string& new_owner) {
	bus_->AssertOnOriginThread();

	bus_->GetDBusTaskRunner()->PostTask(
	FROM_HERE,
	base::BindOnce(&ObjectManager::UpdateServiceNameOwner, this, new_owner));

	if (!old_owner.empty()) {
	ObjectMap::iterator iter = object_map_.begin();
	while (iter != object_map_.end()) {
	ObjectMap::iterator tmp = iter;
	++iter;

	// PropertiesMap is mutated by RemoveInterface, and also Object is
	// destroyed; easier to collect the object path and interface names
	// and remove them safely.
	const dbus::ObjectPath object_path = tmp->first;
	Object* object = tmp->second;
	std::vector<std::string> interfaces;

	for (Object::PropertiesMap::iterator piter =
	object->properties_map.begin();
	piter != object->properties_map.end(); ++piter)
	interfaces.push_back(piter->first);

	for (std::vector<std::string>::iterator iiter = interfaces.begin();
	iiter != interfaces.end(); ++iiter)
	RemoveInterface(object_path, *iiter);
	}

	}

	if (!new_owner.empty())
	GetManagedObjects();
	}

	} // namespace dbus