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 - 2010, Intel Corporation. All rights reserved.<BR>
   6   This program and the accompanying materials
   7   are licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #ifndef __DEVICE_PATH_UTILITIES_PROTOCOL_H__
  17 #define __DEVICE_PATH_UTILITIES_PROTOCOL_H__
  18
  19 ///
  20 /// Device Path Utilities protocol
  21 ///
  22 #define EFI_DEVICE_PATH_UTILITIES_PROTOCOL_GUID \
  23   { \
  24     0x379be4e, 0xd706, 0x437d, {0xb0, 0x37, 0xed, 0xb8, 0x2f, 0xb7, 0x72, 0xa4 } \
  25   }
  26
  27 /**
  28   Returns the size of the device path, in bytes.
  29
  30   @param  DevicePath Points to the start of the EFI device path.
  31
  32   @return Size  Size of the specified device path, in bytes, including the end-of-path tag.
  33   @retval 0     DevicePath is NULL
  34
  35 **/
  36 typedef
  37 UINTN
  38 (EFIAPI *EFI_DEVICE_PATH_UTILS_GET_DEVICE_PATH_SIZE)(
  39   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
  40   );
  41
  42
  43 /**
  44   Create a duplicate of the specified path.
  45
  46   @param  DevicePath Points to the source EFI device path.
  47
  48   @retval Pointer    A pointer to the duplicate device path.
  49   @retval NULL       insufficient memory or DevicePath is NULL
  50
  51 **/
  52 typedef
  53 EFI_DEVICE_PATH_PROTOCOL*
  54 (EFIAPI *EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH)(
  55   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
  56   );
  57
  58 /**
  59   Create a new path by appending the second device path to the first.
  60   If Src1 is NULL and Src2 is non-NULL, then a duplicate of Src2 is returned.
  61   If Src1 is non-NULL and Src2 is NULL, then a duplicate of Src1 is returned.
  62   If Src1 and Src2 are both NULL, then a copy of an end-of-device-path is returned.
  63
  64   @param  Src1 Points to the first device path.
  65   @param  Src2 Points to the second device path.
  66
  67   @retval Pointer  A pointer to the newly created device path.
  68   @retval NULL     Memory could not be allocated
  69
  70 **/
  71 typedef
  72 EFI_DEVICE_PATH_PROTOCOL*
  73 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_PATH)(
  74   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src1,
  75   IN CONST EFI_DEVICE_PATH_PROTOCOL *Src2
  76   );
  77
  78 /**
  79   Creates a new path by appending the device node to the device path.
  80   If DeviceNode is NULL then a copy of DevicePath is returned.
  81   If DevicePath is NULL then a copy of DeviceNode, followed by an end-of-device path device node is returned.
  82   If both DeviceNode and DevicePath are NULL then a copy of an end-of-device-path device node is returned.
  83
  84   @param  DevicePath Points to the device path.
  85   @param  DeviceNode Points to the device node.
  86
  87   @retval Pointer    A pointer to the allocated device node.
  88   @retval NULL       There was insufficient memory.
  89
  90 **/
  91 typedef
  92 EFI_DEVICE_PATH_PROTOCOL*
  93 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_NODE)(
  94   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
  95   IN CONST EFI_DEVICE_PATH_PROTOCOL *DeviceNode
  96   );
  97
  98 /**
  99   Creates a new path by appending the specified device path instance to the specified device path.
 100
 101   @param  DevicePath         Points to the device path. If NULL, then ignored.
 102   @param  DevicePathInstance Points to the device path instance.
 103
 104   @retval Pointer            A pointer to the newly created device path
 105   @retval NULL               Memory could not be allocated or DevicePathInstance is NULL.
 106
 107 **/
 108 typedef
 109 EFI_DEVICE_PATH_PROTOCOL*
 110 (EFIAPI *EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE)(
 111   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 112   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance
 113   );
 114
 115 /**
 116   Creates a copy of the current device path instance and returns a pointer to the next device path
 117   instance.
 118
 119   @param  DevicePathInstance     On input, this holds the pointer to the current device path
 120                                  instance. On output, this holds the pointer to the next
 121                                  device path instance or NULL if there are no more device
 122                                  path instances in the device path.
 123   @param  DevicePathInstanceSize On output, this holds the size of the device path instance,
 124                                  in bytes or zero, if DevicePathInstance is NULL.
 125                                  If NULL, then the instance size is not output.
 126
 127   @retval Pointer                A pointer to the copy of the current device path instance.
 128   @retval NULL                   DevicePathInstace was NULL on entry or there was insufficient memory.
 129
 130 **/
 131 typedef
 132 EFI_DEVICE_PATH_PROTOCOL*
 133 (EFIAPI *EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE)(
 134   IN  OUT EFI_DEVICE_PATH_PROTOCOL  **DevicePathInstance,
 135   OUT UINTN                         *DevicePathInstanceSize
 136   );
 137
 138 /**
 139   Creates a device node
 140
 141   @param  NodeType    NodeType is the device node type (EFI_DEVICE_PATH.Type) for
 142                       the new device node.
 143   @param  NodeSubType NodeSubType is the device node sub-type
 144                       EFI_DEVICE_PATH.SubType) for the new device node.
 145   @param  NodeLength  NodeLength is the length of the device node
 146                       (EFI_DEVICE_PATH.Length) for the new device node.
 147
 148   @retval Pointer     A pointer to the newly created device node.
 149   @retval NULL        NodeLength is less than
 150                       the size of the header or there was insufficient memory.
 151
 152 **/
 153 typedef
 154 EFI_DEVICE_PATH_PROTOCOL*
 155 (EFIAPI *EFI_DEVICE_PATH_UTILS_CREATE_NODE)(
 156   IN UINT8                          NodeType,
 157   IN UINT8                          NodeSubType,
 158   IN UINT16                         NodeLength
 159 );
 160
 161 /**
 162   Returns whether a device path is multi-instance.
 163
 164   @param  DevicePath Points to the device path. If NULL, then ignored.
 165
 166   @retval TRUE       The device path has more than one instance
 167   @retval FALSE      The device path is empty or contains only a single instance.
 168
 169 **/
 170 typedef
 171 BOOLEAN
 172 (EFIAPI *EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE)(
 173   IN CONST EFI_DEVICE_PATH_PROTOCOL         *DevicePath
 174   );
 175
 176 ///
 177 /// This protocol is used to creates and manipulates device paths and device nodes.
 178 ///
 179 typedef struct {
 180   EFI_DEVICE_PATH_UTILS_GET_DEVICE_PATH_SIZE GetDevicePathSize;
 181   EFI_DEVICE_PATH_UTILS_DUP_DEVICE_PATH      DuplicateDevicePath;
 182   EFI_DEVICE_PATH_UTILS_APPEND_PATH          AppendDevicePath;
 183   EFI_DEVICE_PATH_UTILS_APPEND_NODE          AppendDeviceNode;
 184   EFI_DEVICE_PATH_UTILS_APPEND_INSTANCE      AppendDevicePathInstance;
 185   EFI_DEVICE_PATH_UTILS_GET_NEXT_INSTANCE    GetNextDevicePathInstance;
 186   EFI_DEVICE_PATH_UTILS_IS_MULTI_INSTANCE    IsDevicePathMultiInstance;
 187   EFI_DEVICE_PATH_UTILS_CREATE_NODE          CreateDeviceNode;
 188 } EFI_DEVICE_PATH_UTILITIES_PROTOCOL;
 189
 190 extern EFI_GUID gEfiDevicePathUtilitiesProtocolGuid;
 191
 192 #endif