1 // Copyright 2014 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CHROMEOS_DBUS_BLUETOOTH_GATT_CHARACTERISTIC_CLIENT_H_ 6 #define CHROMEOS_DBUS_BLUETOOTH_GATT_CHARACTERISTIC_CLIENT_H_ 7 8 #include <string> 9 10 #include "base/basictypes.h" 11 #include "base/callback.h" 12 #include "chromeos/chromeos_export.h" 13 #include "chromeos/dbus/dbus_client.h" 14 #include "dbus/object_path.h" 15 #include "dbus/property.h" 16 17 namespace chromeos { 18 19 // BluetoothGattCharacteristicClient is used to communicate with remote GATT 20 // characteristic objects exposed by the Bluetooth daemon. 21 class CHROMEOS_EXPORT BluetoothGattCharacteristicClient : public DBusClient { 22 public: 23 // Structure of properties associated with GATT characteristics. 24 struct Properties : public dbus::PropertySet { 25 // The 128-bit characteristic UUID. [read-only] 26 dbus::Property<std::string> uuid; 27 28 // Object path of the GATT service the characteristic belongs to. 29 // [read-only] 30 dbus::Property<dbus::ObjectPath> service; 31 32 // Whether or not this characteristic is currently sending ValueUpdated 33 // signals. 34 dbus::Property<bool> notifying; 35 36 // List of flags representing the GATT "Characteristic Properties bit field" 37 // and properties read from the GATT "Characteristic Extended Properties" 38 // descriptor bit field. [read-only, optional] 39 dbus::Property<std::vector<std::string> > flags; 40 41 Properties(dbus::ObjectProxy* object_proxy, 42 const std::string& interface_name, 43 const PropertyChangedCallback& callback); 44 virtual ~Properties(); 45 }; 46 47 // Interface for observing changes from a remote GATT characteristic. 48 class Observer { 49 public: ~Observer()50 virtual ~Observer() {} 51 52 // Called when the GATT characteristic with object path |object_path| is 53 // added to the system. GattCharacteristicAdded(const dbus::ObjectPath & object_path)54 virtual void GattCharacteristicAdded(const dbus::ObjectPath& object_path) {} 55 56 // Called when the GATT characteristic with object path |object_path| is 57 // removed from the system. GattCharacteristicRemoved(const dbus::ObjectPath & object_path)58 virtual void GattCharacteristicRemoved( 59 const dbus::ObjectPath& object_path) {} 60 61 // Called when the GATT characteristic with object path |object_path| has a 62 // change in the value of the property named |property_name|. GattCharacteristicPropertyChanged(const dbus::ObjectPath & object_path,const std::string & property_name)63 virtual void GattCharacteristicPropertyChanged( 64 const dbus::ObjectPath& object_path, 65 const std::string& property_name) {} 66 67 // Called when a "ValueUpdated" signal is received from the remote GATT 68 // characteristic with object path |object_path| with characteristic value 69 // |value|. GattCharacteristicValueUpdated(const dbus::ObjectPath & object_path,const std::vector<uint8> & value)70 virtual void GattCharacteristicValueUpdated( 71 const dbus::ObjectPath& object_path, 72 const std::vector<uint8>& value) {} 73 }; 74 75 // Callbacks used to report the result of asynchronous methods. 76 typedef base::Callback<void(const std::string& error_name, 77 const std::string& error_message)> ErrorCallback; 78 typedef base::Callback<void(const std::vector<uint8>& value)> ValueCallback; 79 80 virtual ~BluetoothGattCharacteristicClient(); 81 82 // Adds and removes observers for events on all remote GATT characteristics. 83 // Check the |object_path| parameter of observer methods to determine which 84 // GATT characteristic is issuing the event. 85 virtual void AddObserver(Observer* observer) = 0; 86 virtual void RemoveObserver(Observer* observer) = 0; 87 88 // Returns the list of GATT characteristic object paths known to the system. 89 virtual std::vector<dbus::ObjectPath> GetCharacteristics() = 0; 90 91 // Obtain the properties for the GATT characteristic with object path 92 // |object_path|. Values should be copied if needed. 93 virtual Properties* GetProperties(const dbus::ObjectPath& object_path) = 0; 94 95 // Issues a request to read the value of GATT characteristic with object path 96 // |object_path| and returns the value in |callback| on success. On error, 97 // invokes |error_callback|. 98 virtual void ReadValue(const dbus::ObjectPath& object_path, 99 const ValueCallback& callback, 100 const ErrorCallback& error_callback) = 0; 101 102 // Issues a request to write the value of GATT characteristic with object path 103 // |object_path| with value |value|. Invokes |callback| on success and 104 // |error_callback| on failure. 105 virtual void WriteValue(const dbus::ObjectPath& object_path, 106 const std::vector<uint8>& value, 107 const base::Closure& callback, 108 const ErrorCallback& error_callback) = 0; 109 110 // Starts a notification session from this characteristic with object path 111 // |object_path| if it supports value notifications or indications. Invokes 112 // |callback| on success and |error_callback| on failure. 113 virtual void StartNotify(const dbus::ObjectPath& object_path, 114 const base::Closure& callback, 115 const ErrorCallback& error_callback) = 0; 116 117 // Cancels any previous StartNotify transaction for characteristic with 118 // object path |object_path|. Invokes |callback| on success and 119 // |error_callback| on failure. 120 virtual void StopNotify(const dbus::ObjectPath& object_path, 121 const base::Closure& callback, 122 const ErrorCallback& error_callback) = 0; 123 124 // Creates the instance. 125 static BluetoothGattCharacteristicClient* Create(); 126 127 // Constants used to indicate exceptional error conditions. 128 static const char kNoResponseError[]; 129 static const char kUnknownCharacteristicError[]; 130 131 protected: 132 BluetoothGattCharacteristicClient(); 133 134 private: 135 DISALLOW_COPY_AND_ASSIGN(BluetoothGattCharacteristicClient); 136 }; 137 138 } // namespace chromeos 139 140 #endif // CHROMEOS_DBUS_BLUETOOTH_GATT_CHARACTERISTIC_CLIENT_H_ 141