EdkCompatibilityPkg/Foundation/Library/Dxe/Include/RtDevicePath.h

   1 /*++
   2
   3 Copyright (c) 2006, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13
  14   RtDevicePath.h
  15
  16 Abstract:
  17
  18   Device Path services. The thing to remember is device paths are built out of
  19   nodes. The device path is terminated by an end node that is length
  20   sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL)
  21   all over this file.
  22
  23   The only place where multi-instance device paths are supported is in
  24   environment varibles. Multi-instance device paths should never be placed
  25   on a Handle.
  26
  27 --*/
  28 #ifndef _RT_DEVICE_PATH_H_
  29 #define _RT_DEVICE_PATH_H_
  30
  31 BOOLEAN
  32 RtEfiIsDevicePathMultiInstance (
  33   IN EFI_DEVICE_PATH_PROTOCOL  *DevicePath
  34   )
  35 /*++
  36
  37 Routine Description:
  38   Return TRUE is this is a multi instance device path.
  39
  40 Arguments:
  41   DevicePath  - A pointer to a device path data structure.
  42
  43
  44 Returns:
  45   TRUE - If DevicePath is multi instance.
  46   FALSE - If DevicePath is not multi instance.
  47
  48 --*/
  49 ;
  50
  51 EFI_DEVICE_PATH_PROTOCOL        *
  52 RtEfiDevicePathInstance (
  53   IN OUT EFI_DEVICE_PATH_PROTOCOL   **DevicePath,
  54   OUT UINTN                         *Size
  55   )
  56 /*++
  57
  58 Routine Description:
  59   Function retrieves the next device path instance from a device path data structure.
  60
  61 Arguments:
  62   DevicePath           - A pointer to a device path data structure.
  63
  64   Size                 - A pointer to the size of a device path instance in bytes.
  65
  66 Returns:
  67
  68   This function returns a pointer to the current device path instance.
  69   In addition, it returns the size in bytes of the current device path instance in Size,
  70   and a pointer to the next device path instance in DevicePath.
  71   If there are no more device path instances in DevicePath, then DevicePath will be set to NULL.
  72
  73 --*/
  74 ;
  75
  76 UINTN
  77 RtEfiDevicePathSize (
  78   IN EFI_DEVICE_PATH_PROTOCOL  *DevPath
  79   )
  80 /*++
  81
  82 Routine Description:
  83
  84   Calculate the size of a whole device path.
  85
  86 Arguments:
  87
  88   DevPath - The pointer to the device path data.
  89
  90 Returns:
  91
  92   Size of device path data structure..
  93
  94 --*/
  95 ;
  96
  97 EFI_DEVICE_PATH_PROTOCOL        *
  98 RtEfiAppendDevicePath (
  99   IN EFI_DEVICE_PATH_PROTOCOL  *Src1,
 100   IN EFI_DEVICE_PATH_PROTOCOL  *Src2
 101   )
 102 /*++
 103
 104 Routine Description:
 105   Function is used to append a Src1 and Src2 together.
 106
 107 Arguments:
 108   Src1  - A pointer to a device path data structure.
 109
 110   Src2  - A pointer to a device path data structure.
 111
 112 Returns:
 113
 114   A pointer to the new device path is returned.
 115   NULL is returned if space for the new device path could not be allocated from pool.
 116   It is up to the caller to free the memory used by Src1 and Src2 if they are no longer needed.
 117
 118 --*/
 119 ;
 120
 121 EFI_DEVICE_PATH_PROTOCOL        *
 122 RtEfiDevicePathFromHandle (
 123   IN EFI_HANDLE       Handle
 124   )
 125 /*++
 126
 127 Routine Description:
 128
 129   Locate device path protocol interface on a device handle.
 130
 131 Arguments:
 132
 133   Handle  - The device handle
 134
 135 Returns:
 136
 137   Device path protocol interface located.
 138
 139 --*/
 140 ;
 141
 142 EFI_DEVICE_PATH_PROTOCOL        *
 143 RtEfiDuplicateDevicePath (
 144   IN EFI_DEVICE_PATH_PROTOCOL  *DevPath
 145   )
 146 /*++
 147
 148 Routine Description:
 149   Duplicate a new device path data structure from the old one.
 150
 151 Arguments:
 152   DevPath  - A pointer to a device path data structure.
 153
 154 Returns:
 155   A pointer to the new allocated device path data.
 156   Caller must free the memory used by DevicePath if it is no longer needed.
 157
 158 --*/
 159 ;
 160
 161 EFI_DEVICE_PATH_PROTOCOL        *
 162 RtEfiAppendDevicePathNode (
 163   IN EFI_DEVICE_PATH_PROTOCOL  *Src1,
 164   IN EFI_DEVICE_PATH_PROTOCOL  *Src2
 165   )
 166 /*++
 167
 168 Routine Description:
 169   Function is used to append a device path node to the end of another device path.
 170
 171 Arguments:
 172   Src1  - A pointer to a device path data structure.
 173
 174   Src2 - A pointer to a device path data structure.
 175
 176 Returns:
 177   This function returns a pointer to the new device path.
 178   If there is not enough temporary pool memory available to complete this function,
 179   then NULL is returned.
 180
 181
 182 --*/
 183 ;
 184
 185 EFI_DEVICE_PATH_PROTOCOL        *
 186 RtEfiFileDevicePath (
 187   IN EFI_HANDLE               Device  OPTIONAL,
 188   IN CHAR16                   *FileName
 189   )
 190 /*++
 191
 192 Routine Description:
 193   Create a device path that appends a MEDIA_DEVICE_PATH with
 194   FileNameGuid to the device path of DeviceHandle.
 195
 196 Arguments:
 197   Device   - Optional Device Handle to use as Root of the Device Path
 198
 199   FileName - FileName
 200
 201 Returns:
 202   EFI_DEVICE_PATH_PROTOCOL that was allocated from dynamic memory
 203   or NULL pointer.
 204
 205 --*/
 206 ;
 207
 208 EFI_DEVICE_PATH_PROTOCOL        *
 209 RtEfiAppendDevicePathInstance (
 210   IN EFI_DEVICE_PATH_PROTOCOL  *Src,
 211   IN EFI_DEVICE_PATH_PROTOCOL  *Instance
 212   )
 213 /*++
 214
 215 Routine Description:
 216
 217   Append a device path instance to another.
 218
 219 Arguments:
 220
 221   Src       - The device path instance to be appended with.
 222   Instance  - The device path instance appending the other.
 223
 224 Returns:
 225
 226   The contaction of these two.
 227
 228 --*/
 229 ;
 230
 231 #endif