MdeModulePkg/Universal/DevicePathDxe/DevicePathUtilities.c

   1 /** @file
   2   Implementation file for Device Path Utilities Protocol
   3
   4 Copyright (c) 2006 - 2008, Intel Corporation. <BR>
   5 All rights reserved. This program and the accompanying materials
   6 are licensed and made available under the terms and conditions of the BSD License
   7 which accompanies this distribution.  The full text of the license may be found at
   8 http://opensource.org/licenses/bsd-license.php
   9
  10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "DevicePath.h"
  16
  17 /**
  18   Returns the size of a device path in bytes.
  19
  20   This function returns the size, in bytes, of the device path data structure specified by
  21   DevicePath including the end of device path node.  If DevicePath is NULL, then 0 is returned.
  22
  23   @param  DevicePath                 A pointer to a device path data structure.
  24
  25   @return The size of a device path in bytes.
  26
  27 **/
  28 UINTN
  29 EFIAPI
  30 GetDevicePathSizeProtocolInterface (
  31   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
  32   )
  33 {
  34   return GetDevicePathSize (DevicePath);
  35 }
  36
  37
  38 /**
  39   Creates a new device path by appending a second device path to a first device path.
  40
  41   This function allocates space for a new copy of the device path specified by DevicePath.  If
  42   DevicePath is NULL, then NULL is returned.  If the memory is successfully allocated, then the
  43   contents of DevicePath are copied to the newly allocated buffer, and a pointer to that buffer
  44   is returned.  Otherwise, NULL is returned.
  45
  46   @param  DevicePath                 A pointer to a device path data structure.
  47
  48   @return A pointer to the duplicated device path.
  49
  50 **/
  51 EFI_DEVICE_PATH_PROTOCOL *
  52 EFIAPI
  53 DuplicateDevicePathProtocolInterface (
  54   IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath
  55   )
  56 {
  57   return DuplicateDevicePath (DevicePath);
  58 }
  59
  60 /**
  61   Creates a new device path by appending a second device path to a first device path.
  62
  63   This function creates a new device path by appending a copy of SecondDevicePath to a copy of
  64   FirstDevicePath in a newly allocated buffer.  Only the end-of-device-path device node from
  65   SecondDevicePath is retained. The newly created device path is returned.
  66   If FirstDevicePath is NULL, then it is ignored, and a duplicate of SecondDevicePath is returned.
  67   If SecondDevicePath is NULL, then it is ignored, and a duplicate of FirstDevicePath is returned.
  68   If both FirstDevicePath and SecondDevicePath are NULL, then a copy of an end-of-device-path is
  69   returned.
  70   If there is not enough memory for the newly allocated buffer, then NULL is returned.
  71   The memory for the new device path is allocated from EFI boot services memory. It is the
  72   responsibility of the caller to free the memory allocated.
  73
  74   @param  FirstDevicePath            A pointer to a device path data structure.
  75   @param  SecondDevicePath           A pointer to a device path data structure.
  76
  77   @return A pointer to the new device path.
  78
  79 **/
  80 EFI_DEVICE_PATH_PROTOCOL *
  81 EFIAPI
  82 AppendDevicePathProtocolInterface (
  83   IN CONST EFI_DEVICE_PATH_PROTOCOL *FirstDevicePath,
  84   IN CONST EFI_DEVICE_PATH_PROTOCOL *SecondDevicePath
  85   )
  86 {
  87   return AppendDevicePath (FirstDevicePath, SecondDevicePath);
  88 }
  89
  90 /**
  91   Creates a new path by appending the device node to the device path.
  92
  93   This function creates a new device path by appending a copy of the device node specified by
  94   DevicePathNode to a copy of the device path specified by DevicePath in an allocated buffer.
  95   The end-of-device-path device node is moved after the end of the appended device node.
  96   If DevicePathNode is NULL then a copy of DevicePath is returned.
  97   If DevicePath is NULL then a copy of DevicePathNode, followed by an end-of-device path device
  98   node is returned.
  99   If both DevicePathNode and DevicePath are NULL then a copy of an end-of-device-path device node
 100   is returned.
 101   If there is not enough memory to allocate space for the new device path, then NULL is returned.
 102   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
 103   free the memory allocated.
 104
 105   @param  DevicePath                 A pointer to a device path data structure.
 106   @param  DevicePathNode             A pointer to a single device path node.
 107
 108   @return A pointer to the new device path.
 109
 110 **/
 111 EFI_DEVICE_PATH_PROTOCOL *
 112 EFIAPI
 113 AppendDeviceNodeProtocolInterface (
 114   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 115   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathNode
 116   )
 117 {
 118   return AppendDevicePathNode (DevicePath, DevicePathNode);
 119 }
 120
 121 /**
 122   Creates a new device path by appending the specified device path instance to the specified device
 123   path.
 124
 125   This function creates a new device path by appending a copy of the device path instance specified
 126   by DevicePathInstance to a copy of the device path specified by DevicePath in a allocated buffer.
 127   The end-of-device-path device node is moved after the end of the appended device path instance
 128   and a new end-of-device-path-instance node is inserted between.
 129   If DevicePath is NULL, then a copy if DevicePathInstance is returned.
 130   If DevicePathInstance is NULL, then NULL is returned.
 131   If there is not enough memory to allocate space for the new device path, then NULL is returned.
 132   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
 133   free the memory allocated.
 134
 135   @param  DevicePath                 A pointer to a device path data structure.
 136   @param  DevicePathInstance         A pointer to a device path instance.
 137
 138   @return A pointer to the new device path.
 139
 140 **/
 141 EFI_DEVICE_PATH_PROTOCOL *
 142 EFIAPI
 143 AppendDevicePathInstanceProtocolInterface (
 144   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
 145   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance
 146   )
 147 {
 148   return AppendDevicePathInstance (DevicePath, DevicePathInstance);
 149 }
 150
 151 /**
 152   Creates a copy of the current device path instance and returns a pointer to the next device path
 153   instance.
 154
 155   This function creates a copy of the current device path instance. It also updates DevicePath to
 156   point to the next device path instance in the device path (or NULL if no more) and updates Size
 157   to hold the size of the device path instance copy.
 158   If DevicePath is NULL, then NULL is returned.
 159   If there is not enough memory to allocate space for the new device path, then NULL is returned.
 160   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
 161   free the memory allocated.
 162   If Size is NULL, then ASSERT().
 163
 164   @param  DevicePath                 On input, this holds the pointer to the current device path
 165                                      instance. On output, this holds the pointer to the next device
 166                                      path instance or NULL if there are no more device path
 167                                      instances in the device path pointer to a device path data
 168                                      structure.
 169   @param  Size                       On output, this holds the size of the device path instance, in
 170                                      bytes or zero, if DevicePath is NULL.
 171
 172   @return A pointer to the current device path instance.
 173
 174 **/
 175 EFI_DEVICE_PATH_PROTOCOL *
 176 EFIAPI
 177 GetNextDevicePathInstanceProtocolInterface (
 178   IN OUT EFI_DEVICE_PATH_PROTOCOL   **DevicePath,
 179   OUT UINTN                         *Size
 180   )
 181 {
 182   return GetNextDevicePathInstance (DevicePath, Size);
 183 }
 184
 185 /**
 186   Determines if a device path is single or multi-instance.
 187
 188   This function returns TRUE if the device path specified by DevicePath is multi-instance.
 189   Otherwise, FALSE is returned.  If DevicePath is NULL, then FALSE is returned.
 190
 191   @param  DevicePath                 A pointer to a device path data structure.
 192
 193   @retval  TRUE                      DevicePath is multi-instance.
 194   @retval  FALSE                     DevicePath is not multi-instance or DevicePath is NULL.
 195
 196 **/
 197 BOOLEAN
 198 EFIAPI
 199 IsDevicePathMultiInstanceProtocolInterface (
 200   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath
 201   )
 202 {
 203   return IsDevicePathMultiInstance (DevicePath);
 204 }
 205
 206 /**
 207   Creates a copy of the current device path instance and returns a pointer to the next device path
 208   instance.
 209
 210   This function creates a new device node in a newly allocated buffer of size NodeLength and
 211   initializes the device path node header with NodeType and NodeSubType.  The new device path node
 212   is returned.
 213   If NodeLength is smaller than a device path header, then NULL is returned.
 214   If there is not enough memory to allocate space for the new device path, then NULL is returned.
 215   The memory is allocated from EFI boot services memory. It is the responsibility of the caller to
 216   free the memory allocated.
 217
 218   @param  NodeType                   The device node type for the new device node.
 219   @param  NodeSubType                The device node sub-type for the new device node.
 220   @param  NodeLength                 The length of the new device node.
 221
 222   @return The new device path.
 223
 224 **/
 225 EFI_DEVICE_PATH_PROTOCOL *
 226 EFIAPI
 227 CreateDeviceNodeProtocolInterface (
 228   IN UINT8  NodeType,
 229   IN UINT8  NodeSubType,
 230   IN UINT16 NodeLength
 231   )
 232 {
 233   return CreateDeviceNode (NodeType, NodeSubType, NodeLength);
 234 }