DriverStudio 和 WDF驱动 通过GUID获取设备句柄的差别

DriverStudio

/*****************************************************************************
* 功能： 通过GUID打开设备，获得设备句柄
* 参数： 
*****************************************************************************/
HANDLE lOpenByInterface(
  GUID* pClassGuid, // points to the GUID that identifies the interface class
  DWORD instance,  // specifies which instance of the enumerated devices to open
  PDWORD pError  // address of variable to receive error status
  )
{
 HANDLE hDev=0;
 
 CDeviceInterfaceClass DevClass(pClassGuid, pError);

 if (*pError != ERROR_SUCCESS)
  return INVALID_HANDLE_VALUE;

 CDeviceInterface DevInterface(&DevClass, instance, pError);

 if (*pError != ERROR_SUCCESS)
  return INVALID_HANDLE_VALUE;

 hDev = CreateFile(
  DevInterface.DevicePath(),
  GENERIC_READ | GENERIC_WRITE,
  FILE_SHARE_READ | FILE_SHARE_WRITE,
  NULL,
  OPEN_EXISTING,
  FILE_ATTRIBUTE_NORMAL,
  NULL
  );

 if (hDev == INVALID_HANDLE_VALUE)
  *pError = GetLastError();
 
 return hDev;
}

//WDF驱动

HANDLE CxDriverInterface::SetupDevInterfaces(DWORD dev_interface_index, int board_type)
{
 HANDLE hd_invalid = INVALID_HANDLE_VALUE;
 DWORD required_buf_size;
 GUID *pGuid = (LPGUID)&GUID_DEVINTERFACE_ATHENA;

 if ( board_type == Athena_EVK )
 {
  pGuid = (LPGUID)&GUID_DEVINTERFACE_ATHENA;
 }
 else if( (board_type == Atlas_Plus_EVK) || (board_type == Atlas_EVK) )
 {
  pGuid = (LPGUID)&GUID_DEVINTERFACE_ATLAS;
 }

 //Get handle to our device information set that contains requested device information elements
 HDEVINFO devInfoSetHandle = SetupDiGetClassDevs(pGuid, NULL, NULL, DIGCF_PRESENT | DIGCF_INTERFACEDEVICE);
 if ( devInfoSetHandle == INVALID_HANDLE_VALUE )
 {
  TRACE("SetupDiGetClassDevs failed to find device GUID in system! ");
  return hd_invalid;
 }

 SP_INTERFACE_DEVICE_DATA devInterfaceInfo;
 devInterfaceInfo.cbSize = sizeof(devInterfaceInfo);

 // Try to enumerate the device interfaces that are contained in device information set just retrieved
 if( !SetupDiEnumDeviceInterfaces( devInfoSetHandle, NULL, pGuid, dev_interface_index, &devInterfaceInfo ) )
 {
  TRACE("SetupDiEnumDeviceInterfaces failed to enumerate device GUID! ");
  SetupDiDestroyDeviceInfoList(devInfoSetHandle);
  return hd_invalid;
 }

 // Get the required buffer size and allocate proper sized buffer
 SetupDiGetDeviceInterfaceDetail( devInfoSetHandle, &devInterfaceInfo, NULL, 0, &required_buf_size, NULL );
 PSP_INTERFACE_DEVICE_DETAIL_DATA devInterfaceDetail = (PSP_INTERFACE_DEVICE_DETAIL_DATA) malloc (required_buf_size);

 if( devInterfaceDetail == NULL )
 {
  TRACE("SetupDiGetDeviceInterfaceDetail failed! ");
  SetupDiDestroyDeviceInfoList( devInfoSetHandle );
  return hd_invalid;
 }

 // Get details for the device interface
 devInterfaceDetail->cbSize = sizeof(SP_INTERFACE_DEVICE_DETAIL_DATA);
 if( !SetupDiGetDeviceInterfaceDetail( devInfoSetHandle, &devInterfaceInfo, devInterfaceDetail, required_buf_size, NULL, NULL) )
 {
  TRACE("SetupDiGetDeviceInterfaceDetail failed to set SP_INTERFACE_DEVICE_DETAIL_DATA! ");
  SetupDiDestroyDeviceInfoList( devInfoSetHandle );
  delete devInterfaceDetail;
  return hd_invalid;
 }
 //前面这部分在Driverworks中用两个类来完成
 // Get device handle
 LPCWSTR dev_path = devInterfaceDetail->DevicePath;
 HANDLE dev_hd = CreateFile( devInterfaceDetail->DevicePath, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

 if( dev_hd == INVALID_HANDLE_VALUE )
 {
  TRACE("Failed to create device handleB!");
  exit(1);
 }

 delete devInterfaceDetail;

 if ( devInfoSetHandle )
  SetupDiDestroyDeviceInfoList( devInfoSetHandle );

 return dev_hd;
}