MdePkg: Change OPTIONAL keyword usage style

[mirror_edk2.git] / MdePkg / Library / UefiDevicePathLib / UefiDevicePathLibOptionalDevicePathProtocol.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) 2013 - 2018, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
\r
#include "UefiDevicePathLib.h"\r
\r
GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_UTILITIES_PROTOCOL *mDevicePathLibDevicePathUtilities = NULL;\r
GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_TO_TEXT_PROTOCOL   *mDevicePathLibDevicePathToText    = NULL;\r
GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_FROM_TEXT_PROTOCOL *mDevicePathLibDevicePathFromText  = NULL;\r
\r
/**\r
  The constructor function caches the pointer to DevicePathUtilites protocol,\r
  DevicePathToText protocol and DevicePathFromText protocol.\r
\r
  The constructor function locates these three protocols from protocol database.\r
  It will caches the pointer to local protocol instance if that operation fails\r
  and it will always return EFI_SUCCESS.\r
\r
  @param  ImageHandle   The firmware allocated handle for the EFI image.\r
  @param  SystemTable   A pointer to the EFI System Table.\r
\r
  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
UefiDevicePathLibOptionalDevicePathProtocolConstructor (\r
  IN      EFI_HANDLE                ImageHandle,\r
  IN      EFI_SYSTEM_TABLE          *SystemTable\r
  )\r
{\r
  EFI_STATUS                        Status;\r
\r
  Status = gBS->LocateProtocol (\r
                  &gEfiDevicePathUtilitiesProtocolGuid,\r
                  NULL,\r
                  (VOID**) &mDevicePathLibDevicePathUtilities\r
                  );\r
  ASSERT_EFI_ERROR (Status);\r
  ASSERT (mDevicePathLibDevicePathUtilities != NULL);\r
  return Status;\r
}\r
\r
/**\r
  Returns the size of a device path in bytes.\r
\r
  This function returns the size, in bytes, of the device path data structure\r
  specified by DevicePath including the end of device path node.\r
  If DevicePath is NULL or invalid, then 0 is returned.\r
\r
  @param  DevicePath  A pointer to a device path data structure.\r
\r
  @retval 0           If DevicePath is NULL or invalid.\r
  @retval Others      The size of a device path in bytes.\r
\r
**/\r
UINTN\r
EFIAPI\r
GetDevicePathSize (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->GetDevicePathSize (DevicePath);\r
  } else {\r
    return UefiDevicePathLibGetDevicePathSize (DevicePath);\r
  }\r
}\r
\r
/**\r
  Creates a new copy of an existing device path.\r
\r
  This function allocates space for a new copy of the device path specified by DevicePath.\r
  If DevicePath is NULL, then NULL is returned.  If the memory is successfully\r
  allocated, then the contents of DevicePath are copied to the newly allocated\r
  buffer, and a pointer to that buffer is returned.  Otherwise, NULL is returned.\r
  The memory for the new device path is allocated from EFI boot services memory.\r
  It is the responsibility of the caller to free the memory allocated.\r
\r
  @param  DevicePath    A pointer to a device path data structure.\r
\r
  @retval NULL          DevicePath is NULL or invalid.\r
  @retval Others        A pointer to the duplicated device path.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
DuplicateDevicePath (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->DuplicateDevicePath (DevicePath);\r
  } else {\r
    return UefiDevicePathLibDuplicateDevicePath (DevicePath);\r
  }\r
}\r
\r
/**\r
  Creates a new device path by appending a second device path to a first device path.\r
\r
  This function creates a new device path by appending a copy of SecondDevicePath\r
  to a copy of FirstDevicePath in a newly allocated buffer.  Only the end-of-device-path\r
  device node from SecondDevicePath is retained. The newly created device path is\r
  returned. If FirstDevicePath is NULL, then it is ignored, and a duplicate of\r
  SecondDevicePath is returned.  If SecondDevicePath is NULL, then it is ignored,\r
  and a duplicate of FirstDevicePath is returned. If both FirstDevicePath and\r
  SecondDevicePath are NULL, then a copy of an end-of-device-path is returned.\r
\r
  If there is not enough memory for the newly allocated buffer, then NULL is returned.\r
  The memory for the new device path is allocated from EFI boot services memory.\r
  It is the responsibility of the caller to free the memory allocated.\r
\r
  @param  FirstDevicePath            A pointer to a device path data structure.\r
  @param  SecondDevicePath           A pointer to a device path data structure.\r
\r
  @retval NULL      If there is not enough memory for the newly allocated buffer.\r
  @retval NULL      If FirstDevicePath or SecondDevicePath is invalid.\r
  @retval Others    A pointer to the new device path if success.\r
                    Or a copy an end-of-device-path if both FirstDevicePath and SecondDevicePath are NULL.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
AppendDevicePath (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *FirstDevicePath   OPTIONAL,\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *SecondDevicePath  OPTIONAL\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->AppendDevicePath (FirstDevicePath, SecondDevicePath);\r
  } else {\r
    return UefiDevicePathLibAppendDevicePath (FirstDevicePath, SecondDevicePath);\r
  }\r
}\r
\r
/**\r
  Creates a new path by appending the device node to the device path.\r
\r
  This function creates a new device path by appending a copy of the device node\r
  specified by DevicePathNode to a copy of the device path specified by DevicePath\r
  in an allocated buffer. The end-of-device-path device node is moved after the\r
  end of the appended device node.\r
  If DevicePathNode is NULL then a copy of DevicePath is returned.\r
  If DevicePath is NULL then a copy of DevicePathNode, followed by an end-of-device\r
  path device node is returned.\r
  If both DevicePathNode and DevicePath are NULL then a copy of an end-of-device-path\r
  device node is returned.\r
  If there is not enough memory to allocate space for the new device path, then\r
  NULL is returned.\r
  The memory is allocated from EFI boot services memory. It is the responsibility\r
  of the caller to free the memory allocated.\r
\r
  @param  DevicePath                 A pointer to a device path data structure.\r
  @param  DevicePathNode             A pointer to a single device path node.\r
\r
  @retval NULL      If there is not enough memory for the new device path.\r
  @retval Others    A pointer to the new device path if success.\r
                    A copy of DevicePathNode followed by an end-of-device-path node\r
                    if both FirstDevicePath and SecondDevicePath are NULL.\r
                    A copy of an end-of-device-path node if both FirstDevicePath\r
                    and SecondDevicePath are NULL.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
AppendDevicePathNode (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath      OPTIONAL,\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathNode  OPTIONAL\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->AppendDeviceNode (DevicePath, DevicePathNode);\r
  } else {\r
    return UefiDevicePathLibAppendDevicePathNode (DevicePath, DevicePathNode);\r
  }\r
}\r
\r
/**\r
  Creates a new device path by appending the specified device path instance to the specified device\r
  path.\r
\r
  This function creates a new device path by appending a copy of the device path\r
  instance specified by DevicePathInstance to a copy of the device path specified\r
  by DevicePath in a allocated buffer.\r
  The end-of-device-path device node is moved after the end of the appended device\r
  path instance and a new end-of-device-path-instance node is inserted between.\r
  If DevicePath is NULL, then a copy if DevicePathInstance is returned.\r
  If DevicePathInstance is NULL, then NULL is returned.\r
  If DevicePath or DevicePathInstance is invalid, then NULL is returned.\r
  If there is not enough memory to allocate space for the new device path, then\r
  NULL is returned.\r
  The memory is allocated from EFI boot services memory. It is the responsibility\r
  of the caller to free the memory allocated.\r
\r
  @param  DevicePath                 A pointer to a device path data structure.\r
  @param  DevicePathInstance         A pointer to a device path instance.\r
\r
  @return A pointer to the new device path.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
AppendDevicePathInstance (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath         OPTIONAL,\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathInstance OPTIONAL\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->AppendDevicePathInstance (DevicePath, DevicePathInstance);\r
  } else {\r
    return UefiDevicePathLibAppendDevicePathInstance (DevicePath, DevicePathInstance);\r
  }\r
}\r
\r
/**\r
  Creates a copy of the current device path instance and returns a pointer to the next device path\r
  instance.\r
\r
  This function creates a copy of the current device path instance. It also updates\r
  DevicePath to point to the next device path instance in the device path (or NULL\r
  if no more) and updates Size to hold the size of the device path instance copy.\r
  If DevicePath is NULL, then NULL is returned.\r
  If DevicePath points to a invalid device path, then NULL is returned.\r
  If there is not enough memory to allocate space for the new device path, then\r
  NULL is returned.\r
  The memory is allocated from EFI boot services memory. It is the responsibility\r
  of the caller to free the memory allocated.\r
  If Size is NULL, then ASSERT().\r
\r
  @param  DevicePath                 On input, this holds the pointer to the current\r
                                     device path instance. On output, this holds\r
                                     the pointer to the next device path instance\r
                                     or NULL if there are no more device path\r
                                     instances in the device path pointer to a\r
                                     device path data structure.\r
  @param  Size                       On output, this holds the size of the device\r
                                     path instance, in bytes or zero, if DevicePath\r
                                     is NULL.\r
\r
  @return A pointer to the current device path instance.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
GetNextDevicePathInstance (\r
  IN OUT EFI_DEVICE_PATH_PROTOCOL    **DevicePath,\r
  OUT UINTN                          *Size\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->GetNextDevicePathInstance (DevicePath, Size);\r
  } else {\r
    return UefiDevicePathLibGetNextDevicePathInstance (DevicePath, Size);\r
  }\r
}\r
\r
/**\r
  Creates a device node.\r
\r
  This function creates a new device node in a newly allocated buffer of size\r
  NodeLength and initializes the device path node header with NodeType and NodeSubType.\r
  The new device path node is returned.\r
  If NodeLength is smaller than a device path header, then NULL is returned.\r
  If there is not enough memory to allocate space for the new device path, then\r
  NULL is returned.\r
  The memory is allocated from EFI boot services memory. It is the responsibility\r
  of the caller to free the memory allocated.\r
\r
  @param  NodeType                   The device node type for the new device node.\r
  @param  NodeSubType                The device node sub-type for the new device node.\r
  @param  NodeLength                 The length of the new device node.\r
\r
  @return The new device path.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
CreateDeviceNode (\r
  IN UINT8                           NodeType,\r
  IN UINT8                           NodeSubType,\r
  IN UINT16                          NodeLength\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->CreateDeviceNode (NodeType, NodeSubType, NodeLength);\r
  } else {\r
    return UefiDevicePathLibCreateDeviceNode (NodeType, NodeSubType, NodeLength);\r
  }\r
}\r
\r
/**\r
  Determines if a device path is single or multi-instance.\r
\r
  This function returns TRUE if the device path specified by DevicePath is\r
  multi-instance.\r
  Otherwise, FALSE is returned.\r
  If DevicePath is NULL or invalid, then FALSE is returned.\r
\r
  @param  DevicePath                 A pointer to a device path data structure.\r
\r
  @retval  TRUE                      DevicePath is multi-instance.\r
  @retval  FALSE                     DevicePath is not multi-instance, or DevicePath\r
                                     is NULL or invalid.\r
\r
**/\r
BOOLEAN\r
EFIAPI\r
IsDevicePathMultiInstance (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath\r
  )\r
{\r
  if (mDevicePathLibDevicePathUtilities != NULL) {\r
    return mDevicePathLibDevicePathUtilities->IsDevicePathMultiInstance (DevicePath);\r
  } else {\r
    return UefiDevicePathLibIsDevicePathMultiInstance (DevicePath);\r
  }\r
}\r
\r
/**\r
  Locate and return the protocol instance identified by the ProtocolGuid.\r
\r
  @param ProtocolGuid     The GUID of the protocol.\r
\r
  @return A pointer to the protocol instance or NULL when absent.\r
**/\r
VOID *\r
UefiDevicePathLibLocateProtocol (\r
  EFI_GUID                         *ProtocolGuid\r
  )\r
{\r
  EFI_STATUS Status;\r
  VOID       *Protocol;\r
  Status = gBS->LocateProtocol (\r
                  ProtocolGuid,\r
                  NULL,\r
                  (VOID**) &Protocol\r
                  );\r
  if (EFI_ERROR (Status)) {\r
    return NULL;\r
  } else {\r
    return Protocol;\r
  }\r
}\r
\r
/**\r
  Converts a device node to its string representation.\r
\r
  @param DeviceNode        A Pointer to the device node to be converted.\r
  @param DisplayOnly       If DisplayOnly is TRUE, then the shorter text representation\r
                           of the display node is used, where applicable. If DisplayOnly\r
                           is FALSE, then the longer text representation of the display node\r
                           is used.\r
  @param AllowShortcuts    If AllowShortcuts is TRUE, then the shortcut forms of text\r
                           representation for a device node can be used, where applicable.\r
\r
  @return A pointer to the allocated text representation of the device node or NULL if DeviceNode\r
          is NULL or there was insufficient memory.\r
\r
**/\r
CHAR16 *\r
EFIAPI\r
ConvertDeviceNodeToText (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DeviceNode,\r
  IN BOOLEAN                         DisplayOnly,\r
  IN BOOLEAN                         AllowShortcuts\r
  )\r
{\r
  if (mDevicePathLibDevicePathToText == NULL) {\r
    mDevicePathLibDevicePathToText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathToTextProtocolGuid);\r
  }\r
  if (mDevicePathLibDevicePathToText != NULL) {\r
    return mDevicePathLibDevicePathToText->ConvertDeviceNodeToText (DeviceNode, DisplayOnly, AllowShortcuts);\r
  }\r
\r
  return UefiDevicePathLibConvertDeviceNodeToText (DeviceNode, DisplayOnly, AllowShortcuts);\r
}\r
\r
/**\r
  Converts a device path to its text representation.\r
\r
  @param DevicePath      A Pointer to the device to be converted.\r
  @param DisplayOnly     If DisplayOnly is TRUE, then the shorter text representation\r
                         of the display node is used, where applicable. If DisplayOnly\r
                         is FALSE, then the longer text representation of the display node\r
                         is used.\r
  @param AllowShortcuts  If AllowShortcuts is TRUE, then the shortcut forms of text\r
                         representation for a device node can be used, where applicable.\r
\r
  @return A pointer to the allocated text representation of the device path or\r
          NULL if DeviceNode is NULL or there was insufficient memory.\r
\r
**/\r
CHAR16 *\r
EFIAPI\r
ConvertDevicePathToText (\r
  IN CONST EFI_DEVICE_PATH_PROTOCOL   *DevicePath,\r
  IN BOOLEAN                          DisplayOnly,\r
  IN BOOLEAN                          AllowShortcuts\r
  )\r
{\r
  if (mDevicePathLibDevicePathToText == NULL) {\r
    mDevicePathLibDevicePathToText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathToTextProtocolGuid);\r
  }\r
  if (mDevicePathLibDevicePathToText != NULL) {\r
    return mDevicePathLibDevicePathToText->ConvertDevicePathToText (DevicePath, DisplayOnly, AllowShortcuts);\r
  }\r
\r
  return UefiDevicePathLibConvertDevicePathToText (DevicePath, DisplayOnly, AllowShortcuts);\r
}\r
\r
/**\r
  Convert text to the binary representation of a device node.\r
\r
  @param TextDeviceNode  TextDeviceNode points to the text representation of a device\r
                         node. Conversion starts with the first character and continues\r
                         until the first non-device node character.\r
\r
  @return A pointer to the EFI device node or NULL if TextDeviceNode is NULL or there was\r
          insufficient memory or text unsupported.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
ConvertTextToDeviceNode (\r
  IN CONST CHAR16 *TextDeviceNode\r
  )\r
{\r
  if (mDevicePathLibDevicePathFromText == NULL) {\r
    mDevicePathLibDevicePathFromText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathFromTextProtocolGuid);\r
  }\r
  if (mDevicePathLibDevicePathFromText != NULL) {\r
    return mDevicePathLibDevicePathFromText->ConvertTextToDeviceNode (TextDeviceNode);\r
  }\r
\r
  return UefiDevicePathLibConvertTextToDeviceNode (TextDeviceNode);\r
}\r
\r
/**\r
  Convert text to the binary representation of a device path.\r
\r
\r
  @param TextDevicePath  TextDevicePath points to the text representation of a device\r
                         path. Conversion starts with the first character and continues\r
                         until the first non-device node character.\r
\r
  @return A pointer to the allocated device path or NULL if TextDeviceNode is NULL or\r
          there was insufficient memory.\r
\r
**/\r
EFI_DEVICE_PATH_PROTOCOL *\r
EFIAPI\r
ConvertTextToDevicePath (\r
  IN CONST CHAR16 *TextDevicePath\r
  )\r
{\r
  if (mDevicePathLibDevicePathFromText == NULL) {\r
    mDevicePathLibDevicePathFromText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathFromTextProtocolGuid);\r
  }\r
  if (mDevicePathLibDevicePathFromText != NULL) {\r
    return mDevicePathLibDevicePathFromText->ConvertTextToDevicePath (TextDevicePath);\r
  }\r
\r
  return UefiDevicePathLibConvertTextToDevicePath (TextDevicePath);\r
}\r