1# Copyright 2021-2023 Google LLC 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); 4# you may not use this file except in compliance with the License. 5# You may obtain a copy of the License at 6# 7# https://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, 11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12# See the License for the specific language governing permissions and 13# limitations under the License. 14 15# ----------------------------------------------------------------------------- 16# Imports 17# ----------------------------------------------------------------------------- 18import logging 19import grpc 20 21from .common import PumpedTransport, PumpedPacketSource, PumpedPacketSink 22from .emulated_bluetooth_pb2_grpc import EmulatedBluetoothServiceStub 23from .emulated_bluetooth_vhci_pb2_grpc import VhciForwardingServiceStub 24 25# pylint: disable-next=no-name-in-module 26from .emulated_bluetooth_packets_pb2 import HCIPacket 27 28 29# ----------------------------------------------------------------------------- 30# Logging 31# ----------------------------------------------------------------------------- 32logger = logging.getLogger(__name__) 33 34 35# ----------------------------------------------------------------------------- 36async def open_android_emulator_transport(spec): 37 ''' 38 Open a transport connection to an Android emulator via its gRPC interface. 39 The parameter string has this syntax: 40 [<remote-host>:<remote-port>][,mode=<host|controller>] 41 The <remote-host>:<remote-port> part is optional, it defaults to localhost:8554 42 The mode=<mode> part is optional, it defaults to mode=host 43 When the mode is set to 'controller', the connection is for a controller (i.e the 44 Android Bluetooth stack will use the connected endpoint as its controller). When 45 the mode is set to 'host', the connection is to the 'Root Canal' virtual controller 46 that runs as part of the emulator, and used by the Android Bluetooth stack. 47 48 Examples: 49 (empty string) --> connect as a host to the emulator on localhost:8554 50 localhost:8555 --> connect as a host to the emulator on localhost:8555 51 mode=controller --> connect as a controller to the emulator on localhost:8554 52 ''' 53 54 # Wrapper for I/O operations 55 class HciDevice: 56 def __init__(self, hci_device): 57 self.hci_device = hci_device 58 59 async def read(self): 60 packet = await self.hci_device.read() 61 return bytes([packet.type]) + packet.packet 62 63 async def write(self, packet): 64 await self.hci_device.write(HCIPacket(type=packet[0], packet=packet[1:])) 65 66 # Parse the parameters 67 mode = 'host' 68 server_host = 'localhost' 69 server_port = 8554 70 if spec is not None: 71 params = spec.split(',') 72 for param in params: 73 if param.startswith('mode='): 74 mode = param.split('=')[1] 75 elif ':' in param: 76 server_host, server_port = param.split(':') 77 else: 78 raise ValueError('invalid parameter') 79 80 # Connect to the gRPC server 81 server_address = f'{server_host}:{server_port}' 82 logger.debug(f'connecting to gRPC server at {server_address}') 83 channel = grpc.aio.insecure_channel(server_address) 84 85 if mode == 'host': 86 # Connect as a host 87 service = EmulatedBluetoothServiceStub(channel) 88 hci_device = HciDevice(service.registerHCIDevice()) 89 elif mode == 'controller': 90 # Connect as a controller 91 service = VhciForwardingServiceStub(channel) 92 hci_device = HciDevice(service.attachVhci()) 93 else: 94 raise ValueError('invalid mode') 95 96 # Create the transport object 97 transport = PumpedTransport( 98 PumpedPacketSource(hci_device.read), 99 PumpedPacketSink(hci_device.write), 100 channel.close, 101 ) 102 transport.start() 103 104 return transport 105