/**************************************************************************** ** ** Copyright (C) 2017 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the QtBluetooth module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 3 as published by the Free Software ** Foundation and appearing in the file LICENSE.LGPL3 included in the ** packaging of this file. Please review the following information to ** ensure the GNU Lesser General Public License version 3 requirements ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 2.0 or (at your option) the GNU General ** Public license version 3 or any later version approved by the KDE Free ** Qt Foundation. The licenses are as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-2.0.html and ** https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/ #include "qlowenergycontroller.h" #include "qlowenergycharacteristicdata.h" #include "qlowenergyconnectionparameters.h" #include "qlowenergydescriptordata.h" #include "qlowenergyservicedata.h" #include #include #if QT_CONFIG(bluez) && !defined(QT_BLUEZ_NO_BTLE) #include "bluez/bluez5_helper_p.h" #include "qlowenergycontroller_bluezdbus_p.h" #include "qlowenergycontroller_bluez_p.h" #elif defined(QT_ANDROID_BLUETOOTH) #include "qlowenergycontroller_android_p.h" #elif defined(QT_WINRT_BLUETOOTH) #include "qlowenergycontroller_winrt_p.h" #else #include "qlowenergycontroller_p.h" #endif #include QT_BEGIN_NAMESPACE Q_DECLARE_LOGGING_CATEGORY(QT_BT) /*! \class QLowEnergyController \inmodule QtBluetooth \brief The QLowEnergyController class provides access to Bluetooth Low Energy Devices. \since 5.4 QLowEnergyController acts as the entry point for Bluetooth Low Energy development. Bluetooth Low Energy defines two types of devices; the peripheral and the central. Each role performs a different task. The peripheral device provides data which is utilized by central devices. An example might be a humidity sensor which measures the moisture in a winter garden. A device such as a mobile phone might read the sensor's value and display it to the user in the greater context of all sensors in the same environment. In this case the sensor is the peripheral device and the mobile phone acts as the central device. A controller in the central role is created via the \l createCentral() factory method. Such an object essentially acts as a placeholder towards a remote Low Energy peripheral device, enabling features such as service discovery and state tracking. After having created a controller object in the central role, the first step is to establish a connection via \l connectToDevice(). Once the connection has been established, the controller's \l state() changes to \l QLowEnergyController::ConnectedState and the \l connected() signal is emitted. It is important to mention that some platforms such as a BlueZ based Linux cannot maintain two connected instances of \l QLowEnergyController to the same remote device. In such cases the second call to \l connectToDevice() may fail. This limitation may disappear at some stage in the future. The \l disconnectFromDevice() function is used to break the existing connection. The second step after establishing the connection is to discover the services offered by the remote peripheral device. This process is started via \l discoverServices() and has finished once the \l discoveryFinished() signal has been emitted. The discovered services can be enumerated via \l services(). The last step is to create service objects. The \l createServiceObject() function acts as factory for each service object and expects the service UUID as parameter. The calling context should take ownership of the returned \l QLowEnergyService instance. Any \l QLowEnergyService, \l QLowEnergyCharacteristic or \l QLowEnergyDescriptor instance which is later created from this controller's connection becomes invalid as soon as the controller disconnects from the remote Bluetooth Low Energy device. A controller in the peripheral role is created via the \l createPeripheral() factory method. Such an object acts as a peripheral device itself, enabling features such as advertising services and allowing clients to get notified about changes to characteristic values. After having created a controller object in the peripheral role, the first step is to populate the set of GATT services offered to client devices via calls to \l addService(). Afterwards, one would call \l startAdvertising() to let the device broadcast some data and, depending on the type of advertising being done, also listen for incoming connections from GATT clients. \sa QLowEnergyService, QLowEnergyCharacteristic, QLowEnergyDescriptor \sa QLowEnergyAdvertisingParameters, QLowEnergyAdvertisingData */ /*! \enum QLowEnergyController::Error Indicates all possible error conditions found during the controller's existence. \value NoError No error has occurred. \value UnknownError An unknown error has occurred. \value UnknownRemoteDeviceError The remote Bluetooth Low Energy device with the address passed to the constructor of this class cannot be found. \value NetworkError The attempt to read from or write to the remote device failed. \value InvalidBluetoothAdapterError The local Bluetooth device with the address passed to the constructor of this class cannot be found or there is no local Bluetooth device. \value ConnectionError The attempt to connect to the remote device failed. This value was introduced by Qt 5.5. \value AdvertisingError The attempt to start advertising failed. This value was introduced by Qt 5.7. \value RemoteHostClosedError The remote device closed the connection. This value was introduced by Qt 5.10. */ /*! \enum QLowEnergyController::ControllerState Indicates the state of the controller object. \value UnconnectedState The controller is not connected to a remote device. \value ConnectingState The controller is attempting to connect to a remote device. \value ConnectedState The controller is connected to a remote device. \value DiscoveringState The controller is retrieving the list of services offered by the remote device. \value DiscoveredState The controller has discovered all services offered by the remote device. \value ClosingState The controller is about to be disconnected from the remote device. \value AdvertisingState The controller is currently advertising data. This value was introduced by Qt 5.7. */ /*! \enum QLowEnergyController::RemoteAddressType Indicates what type of Bluetooth address the remote device uses. \value PublicAddress The remote device uses a public Bluetooth address. \value RandomAddress A random address is a Bluetooth Low Energy security feature. Peripherals using such addresses may frequently change their Bluetooth address. This information is needed when trying to connect to a peripheral. */ /*! \enum QLowEnergyController::Role Indicates the role of the controller object. \value CentralRole The controller acts as a client interacting with a remote device which is in the peripheral role. The controller can initiate connections, discover services and read and write characteristics. \value PeripheralRole The controller can be used to advertise services and handle incoming connections and client requests, acting as a GATT server. A remote device connected to the controller is in the central role. \sa QLowEnergyController::createCentral() \sa QLowEnergyController::createPeripheral() \since 5.7 \note The peripheral role is currently only supported on Linux. In addition, handling the "Signed Write" ATT command on the server side requires BlueZ 5 and kernel version 3.7 or newer. */ /*! \fn void QLowEnergyController::connected() This signal is emitted when the controller successfully connects to the remote Low Energy device (if the controller is in the \l CentralRole) or if a remote Low Energy device connected to the controller (if the controller is in the \l PeripheralRole). On iOS and OS X this signal is not reliable if the controller is in the \l PeripheralRole - the controller only guesses that some central connected to our peripheral as soon as this central tries to write/read a characteristic/descriptor. */ /*! \fn void QLowEnergyController::disconnected() This signal is emitted when the controller disconnects from the remote Low Energy device or vice versa. On iOS and OS X this signal is unreliable if the controller is in the \l PeripheralRole. */ /*! \fn void QLowEnergyController::stateChanged(ControllerState state) This signal is emitted when the controller's state changes. The new \a state can also be retrieved via \l state(). \sa state() */ /*! \fn void QLowEnergyController::error(QLowEnergyController::Error newError) This signal is emitted when an error occurs. The \a newError parameter describes the error that occurred. \sa error(), errorString() */ /*! \fn void QLowEnergyController::serviceDiscovered(const QBluetoothUuid &newService) This signal is emitted each time a new service is discovered. The \a newService parameter contains the UUID of the found service. This signal can only be emitted if the controller is in the \c CentralRole. \sa discoverServices(), discoveryFinished() */ /*! \fn void QLowEnergyController::discoveryFinished() This signal is emitted when the running service discovery finishes. The signal is not emitted if the discovery process finishes with an error. This signal can only be emitted if the controller is in the \l CentralRole. \sa discoverServices(), error() */ /*! \fn void QLowEnergyController::connectionUpdated(const QLowEnergyConnectionParameters &newParameters) This signal is emitted when the connection parameters change. This can happen as a result of calling \l requestConnectionUpdate() or due to other reasons, for instance because the other side of the connection requested new parameters. The new values can be retrieved from \a newParameters. \since 5.7 \sa requestConnectionUpdate() */ void registerQLowEnergyControllerMetaType() { static bool initDone = false; if (!initDone) { qRegisterMetaType(); qRegisterMetaType(); qRegisterMetaType(); qRegisterMetaType(); qRegisterMetaType(); initDone = true; } } static QLowEnergyControllerPrivate *privateController(QLowEnergyController::Role role) { #if QT_CONFIG(bluez) && !defined(QT_BLUEZ_NO_BTLE) // The new DBUS implementation only supports Central role for now // For Peripheral role support see QTBUG-66909 if (role == QLowEnergyController::CentralRole && bluetoothdVersion() >= QVersionNumber(5, 42)) { qCWarning(QT_BT) << "Using BlueZ LE DBus API"; return new QLowEnergyControllerPrivateBluezDBus(); } else { qCWarning(QT_BT) << "Using BlueZ kernel ATT interface"; return new QLowEnergyControllerPrivateBluez(); } #elif defined(QT_ANDROID_BLUETOOTH) Q_UNUSED(role); return new QLowEnergyControllerPrivateAndroid(); #elif defined(QT_WINRT_BLUETOOTH) Q_UNUSED(role); return new QLowEnergyControllerPrivateWinRT(); #else Q_UNUSED(role); return new QLowEnergyControllerPrivateCommon(); #endif } /*! Constructs a new instance of this class with \a parent. The \a remoteDevice must contain the address of the remote Bluetooth Low Energy device to which this object should attempt to connect later on. The controller uses the local default Bluetooth adapter for the connection management. \obsolete */ QLowEnergyController::QLowEnergyController( const QBluetoothAddress &remoteDevice, QObject *parent) : QObject(parent) { d_ptr = privateController(CentralRole); Q_D(QLowEnergyController); d->q_ptr = this; d->role = CentralRole; d->remoteDevice = remoteDevice; d->localAdapter = QBluetoothLocalDevice().address(); d->addressType = QLowEnergyController::PublicAddress; d->init(); } /*! Constructs a new instance of this class with \a parent. The \a remoteDeviceInfo must contain the details of the remote Bluetooth Low Energy device to which this object should attempt to connect later on. The controller uses the local default Bluetooth adapter for the connection management. \since 5.5 \obsolete */ QLowEnergyController::QLowEnergyController( const QBluetoothDeviceInfo &remoteDeviceInfo, QObject *parent) : QObject(parent) { d_ptr = privateController(CentralRole); Q_D(QLowEnergyController); d->q_ptr = this; d->role = CentralRole; d->remoteDevice = remoteDeviceInfo.address(); d->localAdapter = QBluetoothLocalDevice().address(); d->addressType = QLowEnergyController::PublicAddress; d->remoteName = remoteDeviceInfo.name(); d->init(); } /*! Constructs a new instance of this class with \a parent. The \a remoteDevice must contain the address of the remote Bluetooth Low Energy device to which this object should attempt to connect later on. The connection is established via \a localDevice. If \a localDevice is invalid, the local default device is automatically selected. If \a localDevice specifies a local device that is not a local Bluetooth adapter, \l error() is set to \l InvalidBluetoothAdapterError once \l connectToDevice() is called. \obsolete */ QLowEnergyController::QLowEnergyController( const QBluetoothAddress &remoteDevice, const QBluetoothAddress &localDevice, QObject *parent) : QObject(parent) { d_ptr = privateController(CentralRole); Q_D(QLowEnergyController); d->q_ptr = this; d->role = CentralRole; d->remoteDevice = remoteDevice; d->localAdapter = localDevice; d->init(); } /*! Returns a new object of this class that is in the \l CentralRole and has the parent object \a parent. The \a remoteDevice refers to the device that a connection will be established to later. The controller uses the local default Bluetooth adapter for the connection management. \sa QLowEnergyController::CentralRole \since 5.7 */ QLowEnergyController *QLowEnergyController::createCentral(const QBluetoothDeviceInfo &remoteDevice, QObject *parent) { return new QLowEnergyController(remoteDevice, parent); } /*! Returns a new object of this class that is in the \l PeripheralRole and has the parent object \a parent. Typically, the next step is to call \l startAdvertising() on the returned object. The controller uses the local default Bluetooth adapter for the connection management. \sa QLowEnergyController::PeripheralRole \since 5.7 */ QLowEnergyController *QLowEnergyController::createPeripheral(QObject *parent) { return new QLowEnergyController(parent); } QLowEnergyController::QLowEnergyController(QObject *parent) : QObject(parent) { d_ptr = privateController(PeripheralRole); Q_D(QLowEnergyController); d->q_ptr = this; d->role = PeripheralRole; d->localAdapter = QBluetoothLocalDevice().address(); d->init(); } /*! Destroys the QLowEnergyController instance. */ QLowEnergyController::~QLowEnergyController() { disconnectFromDevice(); //in case we were connected delete d_ptr; } /*! Returns the address of the local Bluetooth adapter being used for the communication. If this class instance was requested to use the default adapter but there was no default adapter when creating this class instance, the returned \l QBluetoothAddress will be null. \sa QBluetoothAddress::isNull() */ QBluetoothAddress QLowEnergyController::localAddress() const { return d_ptr->localAdapter; } /*! Returns the address of the remote Bluetooth Low Energy device. For a controller in the \l CentralRole, this value will always be the one passed in when the controller object was created. For a controller in the \l PeripheralRole, this value is the address of the currently connected client device. In particular, this address will be invalid if the controller is not currently in the \l ConnectedState. */ QBluetoothAddress QLowEnergyController::remoteAddress() const { return d_ptr->remoteDevice; } /*! Returns the unique identifier of the remote Bluetooth Low Energy device. On macOS/iOS/tvOS CoreBluetooth does not expose/accept hardware addresses for LE devices; instead developers are supposed to use unique 128-bit UUIDs, generated by CoreBluetooth. These UUIDS will stay constant for the same central <-> peripheral pair and we use them when connecting to a remote device. For a controller in the \l CentralRole, this value will always be the one passed in when the controller object was created. For a controller in the \l PeripheralRole, this value is invalid. \since 5.8 */ QBluetoothUuid QLowEnergyController::remoteDeviceUuid() const { return QBluetoothUuid(); } /*! Returns the name of the remote Bluetooth Low Energy device, if the controller is in the \l CentralRole. Otherwise the result is unspecified. \since 5.5 */ QString QLowEnergyController::remoteName() const { return d_ptr->remoteName; } /*! Returns the current state of the controller. \sa stateChanged() */ QLowEnergyController::ControllerState QLowEnergyController::state() const { return d_ptr->state; } /*! Returns the type of \l remoteAddress(). By default, this value is initialized to \l PublicAddress. \sa setRemoteAddressType() */ QLowEnergyController::RemoteAddressType QLowEnergyController::remoteAddressType() const { return d_ptr->addressType; } /*! Sets the remote address \a type. The type is required to connect to the remote Bluetooth Low Energy device. This attribute is only required to be set on Linux/BlueZ systems with older Linux kernels (v3.3 or lower), or if CAP_NET_ADMIN is not set for the executable. The default value of the attribute is \l RandomAddress. \note All other platforms handle this flag transparently and therefore applications can ignore it entirely. On Linux, the address type flag is not directly exposed by BlueZ although some use cases do require this information. The only way to detect the flag is via the Linux kernel's Bluetooth Management API (kernel version 3.4+ required). This API requires CAP_NET_ADMIN capabilities though. If the local QtBluetooth process has this capability set QtBluetooth will use the API. This assumes that \l QBluetoothDeviceDiscoveryAgent was used prior to calling \l QLowEnergyController::connectToDevice(). */ void QLowEnergyController::setRemoteAddressType( QLowEnergyController::RemoteAddressType type) { d_ptr->addressType = type; } /*! Connects to the remote Bluetooth Low Energy device. This function does nothing if the controller's \l state() is not equal to \l UnconnectedState. The \l connected() signal is emitted once the connection is successfully established. On Linux/BlueZ systems, it is not possible to connect to the same remote device using two instances of this class. The second call to this function may fail with an error. This limitation may be removed in future releases. \sa disconnectFromDevice() */ void QLowEnergyController::connectToDevice() { Q_D(QLowEnergyController); if (role() != CentralRole) { qCWarning(QT_BT) << "Connection can only be established while in central role"; return; } if (!d->isValidLocalAdapter()) { d->setError(QLowEnergyController::InvalidBluetoothAdapterError); return; } if (state() != QLowEnergyController::UnconnectedState) return; d->connectToDevice(); } /*! Disconnects from the remote device. Any \l QLowEnergyService, \l QLowEnergyCharacteristic or \l QLowEnergyDescriptor instance that resulted from the current connection is automatically invalidated. Once any of those objects become invalid they remain invalid even if this controller object reconnects. This function does nothing if the controller is in the \l UnconnectedState. If the controller is in the peripheral role, it stops advertising and removes all services which have previously been added via \l addService(). To reuse the QLowEnergyController instance the application must re-add services and restart the advertising mode by calling \l startAdvertising(). \sa connectToDevice() */ void QLowEnergyController::disconnectFromDevice() { Q_D(QLowEnergyController); if (state() == QLowEnergyController::UnconnectedState) return; d->invalidateServices(); d->disconnectFromDevice(); } /*! Initiates the service discovery process. The discovery progress is indicated via the \l serviceDiscovered() signal. The \l discoveryFinished() signal is emitted when the process has finished. If the controller instance is not connected or the controller has performed the service discovery already this function will do nothing. \note Some platforms internally cache the service list of a device which was discovered in the past. This can be problematic if the remote device changed its list of services or their inclusion tree. If this behavior is a problem, the best workaround is to temporarily turn Bluetooth off. This causes a reset of the cache data. Currently Android exhibits such a cache behavior. */ void QLowEnergyController::discoverServices() { Q_D(QLowEnergyController); if (d->role != CentralRole) { qCWarning(QT_BT) << "Cannot discover services in peripheral role"; return; } if (d->state != QLowEnergyController::ConnectedState) return; d->setState(QLowEnergyController::DiscoveringState); d->discoverServices(); } /*! Returns the list of services offered by the remote device, if the controller is in the \l CentralRole. Otherwise, the result is unspecified. The list contains all primary and secondary services. \sa createServiceObject() */ QList QLowEnergyController::services() const { return d_ptr->serviceList.keys(); } /*! Creates an instance of the service represented by \a serviceUuid. The \a serviceUuid parameter must have been obtained via \l services(). The caller takes ownership of the returned pointer and may pass a \a parent parameter as default owner. This function returns a null pointer if no service with \a serviceUuid can be found on the remote device or the controller is disconnected. This function can return instances for secondary services too. The include relationships between services can be expressed via \l QLowEnergyService::includedServices(). If this function is called multiple times using the same service UUID, the returned \l QLowEnergyService instances share their internal data. Therefore if one of the instances initiates the discovery of the service details, the other instances automatically transition into the discovery state too. \sa services() */ QLowEnergyService *QLowEnergyController::createServiceObject( const QBluetoothUuid &serviceUuid, QObject *parent) { Q_D(QLowEnergyController); QLowEnergyService *service = nullptr; ServiceDataMap::const_iterator it = d->serviceList.constFind(serviceUuid); if (it != d->serviceList.constEnd()) { const QSharedPointer &serviceData = it.value(); service = new QLowEnergyService(serviceData, parent); } return service; } /*! Starts advertising the data given in \a advertisingData and \a scanResponseData, using the parameters set in \a parameters. The controller has to be in the \l PeripheralRole. If \a parameters indicates that the advertisement should be connectable, then this function also starts listening for incoming client connections. Providing \a scanResponseData is not required, as it is not applicable for certain configurations of \c parameters. \a advertisingData and \a scanResponseData are limited to 31 byte user data. If, for example, several 128bit uuids are added to \a advertisingData, the advertised packets may not contain all uuids. The existing limit may have caused the truncation of uuids. In such cases \a scanResponseData may be used for additional information. If this object is currently not in the \l UnconnectedState, nothing happens. \note Advertising will stop automatically once a client connects to the local device. \since 5.7 \sa stopAdvertising() */ void QLowEnergyController::startAdvertising(const QLowEnergyAdvertisingParameters ¶meters, const QLowEnergyAdvertisingData &advertisingData, const QLowEnergyAdvertisingData &scanResponseData) { Q_D(QLowEnergyController); if (role() != PeripheralRole) { qCWarning(QT_BT) << "Cannot start advertising in central role" << state(); return; } if (state() != UnconnectedState) { qCWarning(QT_BT) << "Cannot start advertising in state" << state(); return; } d->startAdvertising(parameters, advertisingData, scanResponseData); } /*! Stops advertising, if this object is currently in the advertising state. The controller has to be in the \l PeripheralRole for this function to work. It does not invalidate services which have previously been added via \l addService(). \since 5.7 \sa startAdvertising() */ void QLowEnergyController::stopAdvertising() { Q_D(QLowEnergyController); if (state() != AdvertisingState) { qCDebug(QT_BT) << "stopAdvertising called in state" << state(); return; } d->stopAdvertising(); } /*! Constructs and returns a \l QLowEnergyService object with \a parent from \a service. The controller must be in the \l PeripheralRole and in the \l UnconnectedState. The \a service object must be valid. \note Once the peripheral instance is disconnected from the remote central device or if \l disconnectFromDevice() is manually called, every service definition that was previously added via this function is removed from the peripheral. Therefore this function must be called again before re-advertising this peripheral controller instance. The described behavior is connection specific and therefore not dependent on whether \l stopAdvertising() was called. \since 5.7 \sa stopAdvertising(), disconnectFromDevice(), QLowEnergyServiceData::addIncludedService */ QLowEnergyService *QLowEnergyController::addService(const QLowEnergyServiceData &service, QObject *parent) { if (role() != PeripheralRole) { qCWarning(QT_BT) << "Services can only be added in the peripheral role"; return nullptr; } if (state() != UnconnectedState) { qCWarning(QT_BT) << "Services can only be added in unconnected state"; return nullptr; } if (!service.isValid()) { qCWarning(QT_BT) << "Not adding invalid service"; return nullptr; } Q_D(QLowEnergyController); QLowEnergyService *newService = d->addServiceHelper(service); if (newService) newService->setParent(parent); return newService; } /*! Requests the controller to update the connection according to \a parameters. If the request is successful, the \l connectionUpdated() signal will be emitted with the actual new parameters. See the \l QLowEnergyConnectionParameters class for more information on connection parameters. Android only indirectly permits the adjustment of this parameter set. The connection parameters are separated into three categories (high, low & balanced priority). Each category implies a pre-configured set of values for \l QLowEnergyConnectionParameters::minimumInterval(), \l QLowEnergyConnectionParameters::maximumInterval() and \l QLowEnergyConnectionParameters::latency(). Although the connection request is an asynchronous operation, Android does not provide a callback stating the result of the request. This is an acknowledged Android bug. Due to this bug Android does not emit the \l connectionUpdated() signal. \note Currently, this functionality is only implemented on Linux and Android. \sa connectionUpdated() \since 5.7 */ void QLowEnergyController::requestConnectionUpdate(const QLowEnergyConnectionParameters ¶meters) { switch (state()) { case ConnectedState: case DiscoveredState: case DiscoveringState: d_ptr->requestConnectionUpdate(parameters); break; default: qCWarning(QT_BT) << "Connection update request only possible in connected state"; } } /*! Returns the last occurred error or \l NoError. */ QLowEnergyController::Error QLowEnergyController::error() const { return d_ptr->error; } /*! Returns a textual representation of the last occurred error. The string is translated. */ QString QLowEnergyController::errorString() const { return d_ptr->errorString; } /*! Returns the role that this controller object is in. The role is determined when constructing a QLowEnergyController instance using \l createCentral() or \l createPeripheral(). \since 5.7 */ QLowEnergyController::Role QLowEnergyController::role() const { return d_ptr->role; } QT_END_NAMESPACE