MdePkg/Include/Protocol/DevicePathUtilities.h

   1 /** @file
   2   EFI_DEVICE_PATH_UTILITIES_PROTOCOL as defined in UEFI 2.0.
   3   Use to create and manipulate device paths and device nodes.
   4
   5   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #ifndef __DEVICE_PATH_UTILITIES_PROTOCOL_H__
  11 #define __DEVICE_PATH_UTILITIES_PROTOCOL_H__
  12
  13 ///
  14 /// Device Path Utilities protocol
  15 ///
  16 #define EFI_DEVICE_PATH_UTILITIES_PROTOCOL_GUID \
  17   { \
  18     0x379be4e, 0xd706, 0x437d, {0xb0, 0x37, 0xed, 0xb8, 0x2f, 0xb7, 0x72, 0xa4 } \
  19   }
  20
  21 /**
  22   Returns the size of the device path, in bytes.
  23
  24   @param  DevicePath Points to the start of the EFI device path.
  25
  26   @return Size  Size of the specified device path, in bytes, including the end-of-path tag.
  27   @retval 0     DevicePath is NULL
  28
  29 **/
  30 typedef
  31 UINTN
  32 (EFIAPI *EFI_DEVICE_PATH_UTILS_GET_DEVICE_PATH_SIZE)(
  33   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
  34   );
  35
  36
  37 /**
  38   Create a duplicate of the specified path.
  39
  40   @param  DevicePath Points to the source EFI device path.
  41
  42   @retval Pointer    A pointer to the duplicate device path.
  43   @retval NULL       insufficient memory or DevicePath is NULL
  44
  45 **/
  46 typedef
  47 EFI_DEVICE_PATH_PROTOCOL*
  48 (EFIAPI *EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH)(
  49   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
  50   );
  51
  52 /**
  53   Create a new path by appending the second device path to the first.
  54   If Src1 is NULL and Src2 is non-NULL, then a duplicate of Src2 is returned.
  55   If Src1 is non-NULL and Src2 is NULL, then a duplicate of Src1 is returned.
  56   If Src1 and Src2 are both NULL, then a copy of an end-of-device-path is returned.
  57
  58   @param  Src1 Points to the first device path.
  59   @param  Src2 Points to the second device path.
  60
  61   @retval Pointer  A pointer to the newly created device path.
  62   @retval NULL     Memory could not be allocated
  63
  64 **/
  65 typedef
  66 EFI_DEVICE_PATH_PROTOCOL*
  67 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_PATH)(
  68   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src1,
  69   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src2
  70   );
  71
  72 /**
  73   Creates a new path by appending the device node to the device path.
  74   If DeviceNode is NULL then a copy of DevicePath is returned.
  75   If DevicePath is NULL then a copy of DeviceNode, followed by an end-of-device path device node is returned.
  76   If both DeviceNode and DevicePath are NULL then a copy of an end-of-device-path device node is returned.
  77
  78   @param  DevicePath Points to the device path.
  79   @param  DeviceNode Points to the device node.
  80
  81   @retval Pointer    A pointer to the allocated device node.
  82   @retval NULL       There was insufficient memory.
  83
  84 **/
  85 typedef
  86 EFI_DEVICE_PATH_PROTOCOL*
  87 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_NODE)(
  88   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
  89   IN CONST EFI_DEVICE_PATH_PROTOCOL *DeviceNode
  90   );
  91
  92 /**
  93   Creates a new path by appending the specified device path instance to the specified device path.
  94
  95   @param  DevicePath         Points to the device path. If NULL, then ignored.
  96   @param  DevicePathInstance Points to the device path instance.
  97
  98   @retval Pointer            A pointer to the newly created device path
  99   @retval NULL               Memory could not be allocated or DevicePathInstance is NULL.
 100
 101 **/
 102 typedef
 103 EFI_DEVICE_PATH_PROTOCOL*
 104 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE)(
 105   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 106   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance
 107   );
 108
 109 /**
 110   Creates a copy of the current device path instance and returns a pointer to the next device path
 111   instance.
 112
 113   @param  DevicePathInstance     On input, this holds the pointer to the current device path
 114                                  instance. On output, this holds the pointer to the next
 115                                  device path instance or NULL if there are no more device
 116                                  path instances in the device path.
 117   @param  DevicePathInstanceSize On output, this holds the size of the device path instance,
 118                                  in bytes or zero, if DevicePathInstance is NULL.
 119                                  If NULL, then the instance size is not output.
 120
 121   @retval Pointer                A pointer to the copy of the current device path instance.
 122   @retval NULL                   DevicePathInstace was NULL on entry or there was insufficient memory.
 123
 124 **/
 125 typedef
 126 EFI_DEVICE_PATH_PROTOCOL*
 127 (EFIAPI *EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE)(
 128   IN  OUT EFI_DEVICE_PATH_PROTOCOL  **DevicePathInstance,
 129   OUT UINTN                         *DevicePathInstanceSize
 130   );
 131
 132 /**
 133   Creates a device node
 134
 135   @param  NodeType    NodeType is the device node type (EFI_DEVICE_PATH.Type) for
 136                       the new device node.
 137   @param  NodeSubType NodeSubType is the device node sub-type
 138                       EFI_DEVICE_PATH.SubType) for the new device node.
 139   @param  NodeLength  NodeLength is the length of the device node
 140                       (EFI_DEVICE_PATH.Length) for the new device node.
 141
 142   @retval Pointer     A pointer to the newly created device node.
 143   @retval NULL        NodeLength is less than
 144                       the size of the header or there was insufficient memory.
 145
 146 **/
 147 typedef
 148 EFI_DEVICE_PATH_PROTOCOL*
 149 (EFIAPI *EFI_DEVICE_PATH_UTILS_CREATE_NODE)(
 150   IN UINT8                          NodeType,
 151   IN UINT8                          NodeSubType,
 152   IN UINT16                         NodeLength
 153 );
 154
 155 /**
 156   Returns whether a device path is multi-instance.
 157
 158   @param  DevicePath Points to the device path. If NULL, then ignored.
 159
 160   @retval TRUE       The device path has more than one instance
 161   @retval FALSE      The device path is empty or contains only a single instance.
 162
 163 **/
 164 typedef
 165 BOOLEAN
 166 (EFIAPI *EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE)(
 167   IN CONST EFI_DEVICE_PATH_PROTOCOL         *DevicePath
 168   );
 169
 170 ///
 171 /// This protocol is used to creates and manipulates device paths and device nodes.
 172 ///
 173 typedef struct {
 174   EFI_DEVICE_PATH_UTILS_GET_DEVICE_PATH_SIZE GetDevicePathSize;
 175   EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH      DuplicateDevicePath;
 176   EFI_DEVICE_PATH_UTILS_APPEND_PATH          AppendDevicePath;
 177   EFI_DEVICE_PATH_UTILS_APPEND_NODE          AppendDeviceNode;
 178   EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE      AppendDevicePathInstance;
 179   EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE    GetNextDevicePathInstance;
 180   EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE    IsDevicePathMultiInstance;
 181   EFI_DEVICE_PATH_UTILS_CREATE_NODE          CreateDeviceNode;
 182 } EFI_DEVICE_PATH_UTILITIES_PROTOCOL;
 183
 184 extern EFI_GUID gEfiDevicePathUtilitiesProtocolGuid;
 185
 186 #endif