gattlib/gattlib-py/gattlib/device.py

228 lines
7.8 KiB
Python

#
# SPDX-License-Identifier: BSD-3-Clause
#
# Copyright (c) 2016-2021, Olivier Martin <olivier@labapart.org>
#
import logging
import uuid
from gattlib import *
from .exception import handle_return, DeviceError
from .gatt import GattService, GattCharacteristic
from .uuid import gattlib_uuid_to_int
CONNECTION_OPTIONS_LEGACY_BDADDR_LE_PUBLIC = (1 << 0)
CONNECTION_OPTIONS_LEGACY_BDADDR_LE_RANDOM = (1 << 1)
CONNECTION_OPTIONS_LEGACY_BT_SEC_LOW = (1 << 2)
CONNECTION_OPTIONS_LEGACY_BT_SEC_MEDIUM = (1 << 3)
CONNECTION_OPTIONS_LEGACY_BT_SEC_HIGH = (1 << 4)
CONNECTION_OPTIONS_LEGACY_DEFAULT = \
CONNECTION_OPTIONS_LEGACY_BDADDR_LE_PUBLIC | \
CONNECTION_OPTIONS_LEGACY_BDADDR_LE_RANDOM | \
CONNECTION_OPTIONS_LEGACY_BT_SEC_LOW
class Device:
def __init__(self, adapter, addr, name=None):
self._adapter = adapter
if type(addr) == str:
self._addr = addr.encode("utf-8")
else:
self._addr = addr
self._name = name
self._connection = None
# Keep track if notification handler has been initialized
self._is_notification_init = False
# Dictionnary for GATT characteristic callback
self._gatt_characteristic_callbacks = {}
@property
def id(self):
return self._addr.decode("utf-8")
@property
def connection(self):
if self._connection:
return self._connection
else:
return c_void_p(None)
def connect(self, options=CONNECTION_OPTIONS_LEGACY_DEFAULT):
if self._adapter:
adapter_name = self._adapter.name
else:
adapter_name = None
self._connection = gattlib_connect(adapter_name, self._addr, options)
if self._connection == 0:
raise DeviceError()
# Disable until https://github.com/labapart/gattlib/issues/75 is resolved
# @property
# def rssi(self):
# _rssi = c_int16(0)
# ret = gattlib_get_rssi(self._connection, byref(_rssi))
# handle_return(ret)
# return _rssi.value
@staticmethod
def on_disconnection(user_data):
this = user_data
this.disconnection_callback(this.disconnection_user_data)
def register_on_disconnect(self, callback, user_data):
self.disconnection_callback = callback
self.disconnection_user_data = user_data
gattlib_register_on_disconnect(self.connection, Device.on_disconnection, self)
def disconnect(self):
ret = gattlib_disconnect(self.connection)
handle_return(ret)
def discover(self):
#
# Discover GATT Services
#
_services = POINTER(GattlibPrimaryService)()
_services_count = c_int(0)
ret = gattlib_discover_primary(self.connection, byref(_services), byref(_services_count))
handle_return(ret)
self._services = {}
for i in range(0, _services_count.value):
service = GattService(self, _services[i])
self._services[service.short_uuid] = service
logging.debug("Service UUID:0x%x" % service.short_uuid)
#
# Discover GATT Characteristics
#
_characteristics = POINTER(GattlibCharacteristic)()
_characteristics_count = c_int(0)
ret = gattlib_discover_char(self.connection, byref(_characteristics), byref(_characteristics_count))
handle_return(ret)
self._characteristics = {}
for i in range(0, _characteristics_count.value):
characteristic = GattCharacteristic(self, _characteristics[i])
self._characteristics[characteristic.short_uuid] = characteristic
logging.debug("Characteristic UUID:0x%x" % characteristic.short_uuid)
def get_advertisement_data(self):
_advertisement_data = POINTER(GattlibAdvertisementData)()
_advertisement_data_count = c_size_t(0)
_manufacturer_id = c_uint16(0)
_manufacturer_data = c_void_p(None)
_manufacturer_data_len = c_size_t(0)
if self._connection is None:
ret = gattlib_get_advertisement_data_from_mac(self._adapter._adapter, self._addr,
byref(_advertisement_data), byref(_advertisement_data_count),
byref(_manufacturer_id),
byref(_manufacturer_data), byref(_manufacturer_data_len))
else:
ret = gattlib_get_advertisement_data(self._connection,
byref(_advertisement_data), byref(_advertisement_data_count),
byref(_manufacturer_id),
byref(_manufacturer_data), byref(_manufacturer_data_len))
handle_return(ret)
advertisement_data = {}
manufacturer_data = None
for i in range(0, _advertisement_data_count.value):
service_data = _advertisement_data[i]
uuid = gattlib_uuid_to_int(service_data.uuid)
pointer_type = POINTER(c_byte * service_data.data_length)
c_bytearray = cast(service_data.data, pointer_type)
data = bytearray(service_data.data_length)
for i in range(service_data.data_length):
data[i] = c_bytearray.contents[i] & 0xFF
advertisement_data[uuid] = data
if _manufacturer_data_len.value > 0:
pointer_type = POINTER(c_byte * _manufacturer_data_len.value)
c_bytearray = cast(_manufacturer_data, pointer_type)
manufacturer_data = bytearray(_manufacturer_data_len.value)
for i in range(_manufacturer_data_len.value):
manufacturer_data[i] = c_bytearray.contents[i] & 0xFF
return advertisement_data, _manufacturer_id.value, manufacturer_data
@property
def services(self):
if not hasattr(self, '_services'):
logging.warning("Start GATT discovery implicitly")
self.discover()
return self._services
@property
def characteristics(self):
if not hasattr(self, '_characteristics'):
logging.warning("Start GATT discovery implicitly")
self.discover()
return self._characteristics
@staticmethod
def notification_callback(uuid_str, data, data_len, user_data):
this = user_data
notification_uuid = uuid.UUID(uuid_str)
short_uuid = notification_uuid.int
if short_uuid not in this._gatt_characteristic_callbacks:
raise RuntimeError("UUID '%s' is expected to be part of the notification list")
else:
characteristic_callback = this._gatt_characteristic_callbacks[short_uuid]
# value = bytearray(data_len)
# for i in range(data_len):
# value[i] = data[i]
pointer_type = POINTER(c_ubyte * data_len)
c_bytearray = cast(data, pointer_type)
value = bytearray(data_len)
for i in range(data_len):
value[i] = c_bytearray.contents[i]
# Call GATT characteristic Notification callback
characteristic_callback['callback'](value, characteristic_callback['user_data'])
def _notification_init(self):
if self._is_notification_init:
return
self._is_notification_init = True
gattlib_register_notification(self._connection, Device.notification_callback, self)
def _notification_add_gatt_characteristic_callback(self, gatt_characteristic, callback, user_data):
if not self._is_notification_init:
self._notification_init()
self._gatt_characteristic_callbacks[gatt_characteristic.short_uuid] = { 'callback': callback, 'user_data': user_data }
def __str__(self):
name = self._name
if name:
return str(name)
else:
return str(self._addr)