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   Create a duplicate of the specified path.
  38
  39   @param  DevicePath Points to the source EFI device path.
  40
  41   @retval Pointer    A pointer to the duplicate device path.
  42   @retval NULL       insufficient memory or DevicePath is NULL
  43
  44 **/
  45 typedef
  46 EFI_DEVICE_PATH_PROTOCOL *
  47 (EFIAPI *EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH)(
  48   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
  49   );
  50
  51 /**
  52   Create a new path by appending the second device path to the first.
  53   If Src1 is NULL and Src2 is non-NULL, then a duplicate of Src2 is returned.
  54   If Src1 is non-NULL and Src2 is NULL, then a duplicate of Src1 is returned.
  55   If Src1 and Src2 are both NULL, then a copy of an end-of-device-path is returned.
  56
  57   @param  Src1 Points to the first device path.
  58   @param  Src2 Points to the second device path.
  59
  60   @retval Pointer  A pointer to the newly created device path.
  61   @retval NULL     Memory could not be allocated
  62
  63 **/
  64 typedef
  65 EFI_DEVICE_PATH_PROTOCOL *
  66 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_PATH)(
  67   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src1,
  68   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src2
  69   );
  70
  71 /**
  72   Creates a new path by appending the device node to the device path.
  73   If DeviceNode is NULL then a copy of DevicePath is returned.
  74   If DevicePath is NULL then a copy of DeviceNode, followed by an end-of-device path device node is returned.
  75   If both DeviceNode and DevicePath are NULL then a copy of an end-of-device-path device node is returned.
  76
  77   @param  DevicePath Points to the device path.
  78   @param  DeviceNode Points to the device node.
  79
  80   @retval Pointer    A pointer to the allocated device node.
  81   @retval NULL       There was insufficient memory.
  82
  83 **/
  84 typedef
  85 EFI_DEVICE_PATH_PROTOCOL *
  86 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_NODE)(
  87   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
  88   IN CONST EFI_DEVICE_PATH_PROTOCOL *DeviceNode
  89   );
  90
  91 /**
  92   Creates a new path by appending the specified device path instance to the specified device path.
  93
  94   @param  DevicePath         Points to the device path. If NULL, then ignored.
  95   @param  DevicePathInstance Points to the device path instance.
  96
  97   @retval Pointer            A pointer to the newly created device path
  98   @retval NULL               Memory could not be allocated or DevicePathInstance is NULL.
  99
 100 **/
 101 typedef
 102 EFI_DEVICE_PATH_PROTOCOL *
 103 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE)(
 104   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 105   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance
 106   );
 107
 108 /**
 109   Creates a copy of the current device path instance and returns a pointer to the next device path
 110   instance.
 111
 112   @param  DevicePathInstance     On input, this holds the pointer to the current device path
 113                                  instance. On output, this holds the pointer to the next
 114                                  device path instance or NULL if there are no more device
 115                                  path instances in the device path.
 116   @param  DevicePathInstanceSize On output, this holds the size of the device path instance,
 117                                  in bytes or zero, if DevicePathInstance is NULL.
 118                                  If NULL, then the instance size is not output.
 119
 120   @retval Pointer                A pointer to the copy of the current device path instance.
 121   @retval NULL                   DevicePathInstace was NULL on entry or there was insufficient memory.
 122
 123 **/
 124 typedef
 125 EFI_DEVICE_PATH_PROTOCOL *
 126 (EFIAPI *EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE)(
 127   IN  OUT EFI_DEVICE_PATH_PROTOCOL  **DevicePathInstance,
 128   OUT UINTN                         *DevicePathInstanceSize
 129   );
 130
 131 /**
 132   Creates a device node
 133
 134   @param  NodeType    NodeType is the device node type (EFI_DEVICE_PATH.Type) for
 135                       the new device node.
 136   @param  NodeSubType NodeSubType is the device node sub-type
 137                       EFI_DEVICE_PATH.SubType) for the new device node.
 138   @param  NodeLength  NodeLength is the length of the device node
 139                       (EFI_DEVICE_PATH.Length) for the new device node.
 140
 141   @retval Pointer     A pointer to the newly created device node.
 142   @retval NULL        NodeLength is less than
 143                       the size of the header or there was insufficient memory.
 144
 145 **/
 146 typedef
 147 EFI_DEVICE_PATH_PROTOCOL *
 148 (EFIAPI *EFI_DEVICE_PATH_UTILS_CREATE_NODE)(
 149   IN UINT8                          NodeType,
 150   IN UINT8                          NodeSubType,
 151   IN UINT16                         NodeLength
 152   );
 153
 154 /**
 155   Returns whether a device path is multi-instance.
 156
 157   @param  DevicePath Points to the device path. If NULL, then ignored.
 158
 159   @retval TRUE       The device path has more than one instance
 160   @retval FALSE      The device path is empty or contains only a single instance.
 161
 162 **/
 163 typedef
 164 BOOLEAN
 165 (EFIAPI *EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE)(
 166   IN CONST EFI_DEVICE_PATH_PROTOCOL         *DevicePath
 167   );
 168
 169 ///
 170 /// This protocol is used to creates and manipulates device paths and device nodes.
 171 ///
 172 typedef struct {
 173   EFI_DEVICE_PATH_UTILS_GET_DEVICE_PATH_SIZE    GetDevicePathSize;
 174   EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH         DuplicateDevicePath;
 175   EFI_DEVICE_PATH_UTILS_APPEND_PATH             AppendDevicePath;
 176   EFI_DEVICE_PATH_UTILS_APPEND_NODE             AppendDeviceNode;
 177   EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE         AppendDevicePathInstance;
 178   EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE       GetNextDevicePathInstance;
 179   EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE       IsDevicePathMultiInstance;
 180   EFI_DEVICE_PATH_UTILS_CREATE_NODE             CreateDeviceNode;
 181 } EFI_DEVICE_PATH_UTILITIES_PROTOCOL;
 182
 183 extern EFI_GUID  gEfiDevicePathUtilitiesProtocolGuid;
 184
 185 #endif