MdePkg: UefiDevicePathLib: Support UefiDevicePathLib under StandaloneMm

[mirror_edk2.git] / MdePkg / Library / UefiDevicePathLib / DevicePathUtilitiesDxeSmm.c

/** @file\r
  Device Path services. The thing to remember is device paths are built out of\r
  nodes. The device path is terminated by an end node that is length\r
  sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL)\r
  all over this file.\r
\r
  The only place where multi-instance device paths are supported is in\r
  environment varibles. Multi-instance device paths should never be placed\r
  on a Handle.\r
\r
  Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
  Copyright (c) Microsoft Corporation.\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "UefiDevicePathLib.h"\r
\r
\r
/**\r
  Retrieves the device path protocol from a handle.\r
\r
  This function returns the device path protocol from the handle specified by Handle.\r
  If Handle is NULL or Handle does not contain a device path protocol, then NULL\r
  is returned.\r
\r
  @param  Handle                     The handle from which to retrieve the device\r
                                     path protocol.\r
\r
  @return The device path protocol from the handle specified by Handle.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
DevicePathFromHandle (\r
  IN EFI_HANDLE                      Handle\r
  )\r
{\r
  EFI_DEVICE_PATH_PROTOCOL  *DevicePath;\r
  EFI_STATUS                Status;\r
\r
  Status = gBS->HandleProtocol (\r
                  Handle,\r
                  &gEfiDevicePathProtocolGuid,\r
                  (VOID *) &DevicePath\r
                  );\r
  if (EFI_ERROR (Status)) {\r
    DevicePath = NULL;\r
  }\r
  return DevicePath;\r
}\r