openpilot代码分析

openpliot

openpliot适配不同车型

openpliot支持不同的车型，代码中对车辆创建了一个抽象模型，根据can信息加载不同的车辆文件。代码逻辑在selfdrive/car/car_helpers.py文件。Controls类初始化时调用了car_helpers的get_car函数获取了两个对象CI(Car Interface)， CP (car Params)。

def get_car(logcan, sendcan, experimental_long_allowed, num_pandas=1):
  candidate, fingerprints, vin, car_fw, source, exact_match = fingerprint(logcan, sendcan, num_pandas)

  if candidate is None:
    cloudlog.event("car doesn't match any fingerprints", fingerprints=fingerprints, error=True)
    candidate = "mock"

  CarInterface, CarController, CarState = interfaces[candidate]
  #创建CP对象
  CP = CarInterface.get_params(candidate, fingerprints, car_fw, experimental_long_allowed, docs=False)
  CP.carVin = vin
  CP.carFw = car_fw
  CP.fingerprintSource = source
  CP.fuzzyFingerprint = not exact_match

  return CarInterface(CP, CarController, CarState), CP

# imports from directory selfdrive/car/<name>/
#_get_interface_names获取selfdrive/car/下的车辆name
interface_names = _get_interface_names()
#load_interfaces import车辆文件：interface.py, carstate.py, carcontroller.py，对应CarInterface, CarController, CarState三个对象
interfaces = load_interfaces(interface_names)

获取到CarInterface对象后，调用CarInterfaceBase类的静态函数get_params，get_params调用CarInterface子类的_get_params对参数进行调整，最终返回CI，CP对象。