1 /** @file 2 Device Path services. The thing to remember is device paths are built out of 3 nodes. The device path is terminated by an end node that is length 4 sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL) 5 all over this file. 6 7 The only place where multi-instance device paths are supported is in 8 environment varibles. Multi-instance device paths should never be placed 9 on a Handle. 10 11 Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR> 12 This program and the accompanying materials 13 are licensed and made available under the terms and conditions of the BSD License 14 which accompanies this distribution. The full text of the license may be found at 15 http://opensource.org/licenses/bsd-license.php. 16 17 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 18 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 19 20 **/ 21 22 23 #include "UefiDevicePathLib.h" 24 25 /** 26 Returns the size of a device path in bytes. 27 28 This function returns the size, in bytes, of the device path data structure 29 specified by DevicePath including the end of device path node. 30 If DevicePath is NULL or invalid, then 0 is returned. 31 32 @param DevicePath A pointer to a device path data structure. 33 34 @retval 0 If DevicePath is NULL or invalid. 35 @retval Others The size of a device path in bytes. 36 37 **/ 38 UINTN 39 EFIAPI 40 GetDevicePathSize ( 41 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath 42 ) 43 { 44 return UefiDevicePathLibGetDevicePathSize (DevicePath); 45 } 46 47 /** 48 Creates a new copy of an existing device path. 49 50 This function allocates space for a new copy of the device path specified by DevicePath. 51 If DevicePath is NULL, then NULL is returned. If the memory is successfully 52 allocated, then the contents of DevicePath are copied to the newly allocated 53 buffer, and a pointer to that buffer is returned. Otherwise, NULL is returned. 54 The memory for the new device path is allocated from EFI boot services memory. 55 It is the responsibility of the caller to free the memory allocated. 56 57 @param DevicePath A pointer to a device path data structure. 58 59 @retval NULL DevicePath is NULL or invalid. 60 @retval Others A pointer to the duplicated device path. 61 62 **/ 63 EFI_DEVICE_PATH_PROTOCOL * 64 EFIAPI 65 DuplicateDevicePath ( 66 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath 67 ) 68 { 69 return UefiDevicePathLibDuplicateDevicePath (DevicePath); 70 } 71 72 /** 73 Creates a new device path by appending a second device path to a first device path. 74 75 This function creates a new device path by appending a copy of SecondDevicePath 76 to a copy of FirstDevicePath in a newly allocated buffer. Only the end-of-device-path 77 device node from SecondDevicePath is retained. The newly created device path is 78 returned. If FirstDevicePath is NULL, then it is ignored, and a duplicate of 79 SecondDevicePath is returned. If SecondDevicePath is NULL, then it is ignored, 80 and a duplicate of FirstDevicePath is returned. If both FirstDevicePath and 81 SecondDevicePath are NULL, then a copy of an end-of-device-path is returned. 82 83 If there is not enough memory for the newly allocated buffer, then NULL is returned. 84 The memory for the new device path is allocated from EFI boot services memory. 85 It is the responsibility of the caller to free the memory allocated. 86 87 @param FirstDevicePath A pointer to a device path data structure. 88 @param SecondDevicePath A pointer to a device path data structure. 89 90 @retval NULL If there is not enough memory for the newly allocated buffer. 91 @retval NULL If FirstDevicePath or SecondDevicePath is invalid. 92 @retval Others A pointer to the new device path if success. 93 Or a copy an end-of-device-path if both FirstDevicePath and SecondDevicePath are NULL. 94 95 **/ 96 EFI_DEVICE_PATH_PROTOCOL * 97 EFIAPI 98 AppendDevicePath ( 99 IN CONST EFI_DEVICE_PATH_PROTOCOL *FirstDevicePath, OPTIONAL 100 IN CONST EFI_DEVICE_PATH_PROTOCOL *SecondDevicePath OPTIONAL 101 ) 102 { 103 return UefiDevicePathLibAppendDevicePath (FirstDevicePath, SecondDevicePath); 104 } 105 106 /** 107 Creates a new path by appending the device node to the device path. 108 109 This function creates a new device path by appending a copy of the device node 110 specified by DevicePathNode to a copy of the device path specified by DevicePath 111 in an allocated buffer. The end-of-device-path device node is moved after the 112 end of the appended device node. 113 If DevicePathNode is NULL then a copy of DevicePath is returned. 114 If DevicePath is NULL then a copy of DevicePathNode, followed by an end-of-device 115 path device node is returned. 116 If both DevicePathNode and DevicePath are NULL then a copy of an end-of-device-path 117 device node is returned. 118 If there is not enough memory to allocate space for the new device path, then 119 NULL is returned. 120 The memory is allocated from EFI boot services memory. It is the responsibility 121 of the caller to free the memory allocated. 122 123 @param DevicePath A pointer to a device path data structure. 124 @param DevicePathNode A pointer to a single device path node. 125 126 @retval NULL If there is not enough memory for the new device path. 127 @retval Others A pointer to the new device path if success. 128 A copy of DevicePathNode followed by an end-of-device-path node 129 if both FirstDevicePath and SecondDevicePath are NULL. 130 A copy of an end-of-device-path node if both FirstDevicePath 131 and SecondDevicePath are NULL. 132 133 **/ 134 EFI_DEVICE_PATH_PROTOCOL * 135 EFIAPI 136 AppendDevicePathNode ( 137 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL 138 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathNode OPTIONAL 139 ) 140 { 141 return UefiDevicePathLibAppendDevicePathNode (DevicePath, DevicePathNode); 142 } 143 144 /** 145 Creates a new device path by appending the specified device path instance to the specified device 146 path. 147 148 This function creates a new device path by appending a copy of the device path 149 instance specified by DevicePathInstance to a copy of the device path specified 150 by DevicePath in a allocated buffer. 151 The end-of-device-path device node is moved after the end of the appended device 152 path instance and a new end-of-device-path-instance node is inserted between. 153 If DevicePath is NULL, then a copy if DevicePathInstance is returned. 154 If DevicePathInstance is NULL, then NULL is returned. 155 If DevicePath or DevicePathInstance is invalid, then NULL is returned. 156 If there is not enough memory to allocate space for the new device path, then 157 NULL is returned. 158 The memory is allocated from EFI boot services memory. It is the responsibility 159 of the caller to free the memory allocated. 160 161 @param DevicePath A pointer to a device path data structure. 162 @param DevicePathInstance A pointer to a device path instance. 163 164 @return A pointer to the new device path. 165 166 **/ 167 EFI_DEVICE_PATH_PROTOCOL * 168 EFIAPI 169 AppendDevicePathInstance ( 170 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL 171 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance OPTIONAL 172 ) 173 { 174 return UefiDevicePathLibAppendDevicePathInstance (DevicePath, DevicePathInstance); 175 } 176 177 /** 178 Creates a copy of the current device path instance and returns a pointer to the next device path 179 instance. 180 181 This function creates a copy of the current device path instance. It also updates 182 DevicePath to point to the next device path instance in the device path (or NULL 183 if no more) and updates Size to hold the size of the device path instance copy. 184 If DevicePath is NULL, then NULL is returned. 185 If DevicePath points to a invalid device path, then NULL is returned. 186 If there is not enough memory to allocate space for the new device path, then 187 NULL is returned. 188 The memory is allocated from EFI boot services memory. It is the responsibility 189 of the caller to free the memory allocated. 190 If Size is NULL, then ASSERT(). 191 192 @param DevicePath On input, this holds the pointer to the current 193 device path instance. On output, this holds 194 the pointer to the next device path instance 195 or NULL if there are no more device path 196 instances in the device path pointer to a 197 device path data structure. 198 @param Size On output, this holds the size of the device 199 path instance, in bytes or zero, if DevicePath 200 is NULL. 201 202 @return A pointer to the current device path instance. 203 204 **/ 205 EFI_DEVICE_PATH_PROTOCOL * 206 EFIAPI 207 GetNextDevicePathInstance ( 208 IN OUT EFI_DEVICE_PATH_PROTOCOL **DevicePath, 209 OUT UINTN *Size 210 ) 211 { 212 return UefiDevicePathLibGetNextDevicePathInstance (DevicePath, Size); 213 } 214 215 /** 216 Creates a device node. 217 218 This function creates a new device node in a newly allocated buffer of size 219 NodeLength and initializes the device path node header with NodeType and NodeSubType. 220 The new device path node is returned. 221 If NodeLength is smaller than a device path header, then NULL is returned. 222 If there is not enough memory to allocate space for the new device path, then 223 NULL is returned. 224 The memory is allocated from EFI boot services memory. It is the responsibility 225 of the caller to free the memory allocated. 226 227 @param NodeType The device node type for the new device node. 228 @param NodeSubType The device node sub-type for the new device node. 229 @param NodeLength The length of the new device node. 230 231 @return The new device path. 232 233 **/ 234 EFI_DEVICE_PATH_PROTOCOL * 235 EFIAPI 236 CreateDeviceNode ( 237 IN UINT8 NodeType, 238 IN UINT8 NodeSubType, 239 IN UINT16 NodeLength 240 ) 241 { 242 return UefiDevicePathLibCreateDeviceNode (NodeType, NodeSubType, NodeLength); 243 } 244 245 /** 246 Determines if a device path is single or multi-instance. 247 248 This function returns TRUE if the device path specified by DevicePath is 249 multi-instance. 250 Otherwise, FALSE is returned. 251 If DevicePath is NULL or invalid, then FALSE is returned. 252 253 @param DevicePath A pointer to a device path data structure. 254 255 @retval TRUE DevicePath is multi-instance. 256 @retval FALSE DevicePath is not multi-instance, or DevicePath 257 is NULL or invalid. 258 259 **/ 260 BOOLEAN 261 EFIAPI 262 IsDevicePathMultiInstance ( 263 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath 264 ) 265 { 266 return UefiDevicePathLibIsDevicePathMultiInstance (DevicePath); 267 } 268 269 /** 270 Converts a device node to its string representation. 271 272 @param DeviceNode A Pointer to the device node to be converted. 273 @param DisplayOnly If DisplayOnly is TRUE, then the shorter text representation 274 of the display node is used, where applicable. If DisplayOnly 275 is FALSE, then the longer text representation of the display node 276 is used. 277 @param AllowShortcuts If AllowShortcuts is TRUE, then the shortcut forms of text 278 representation for a device node can be used, where applicable. 279 280 @return A pointer to the allocated text representation of the device node or NULL if DeviceNode 281 is NULL or there was insufficient memory. 282 283 **/ 284 CHAR16 * 285 EFIAPI 286 ConvertDeviceNodeToText ( 287 IN CONST EFI_DEVICE_PATH_PROTOCOL *DeviceNode, 288 IN BOOLEAN DisplayOnly, 289 IN BOOLEAN AllowShortcuts 290 ) 291 { 292 return UefiDevicePathLibConvertDeviceNodeToText (DeviceNode, DisplayOnly, AllowShortcuts); 293 } 294 295 /** 296 Converts a device path to its text representation. 297 298 @param DevicePath A Pointer to the device to be converted. 299 @param DisplayOnly If DisplayOnly is TRUE, then the shorter text representation 300 of the display node is used, where applicable. If DisplayOnly 301 is FALSE, then the longer text representation of the display node 302 is used. 303 @param AllowShortcuts If AllowShortcuts is TRUE, then the shortcut forms of text 304 representation for a device node can be used, where applicable. 305 306 @return A pointer to the allocated text representation of the device path or 307 NULL if DeviceNode is NULL or there was insufficient memory. 308 309 **/ 310 CHAR16 * 311 EFIAPI 312 ConvertDevicePathToText ( 313 IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, 314 IN BOOLEAN DisplayOnly, 315 IN BOOLEAN AllowShortcuts 316 ) 317 { 318 return UefiDevicePathLibConvertDevicePathToText (DevicePath, DisplayOnly, AllowShortcuts); 319 } 320 321 /** 322 Convert text to the binary representation of a device node. 323 324 @param TextDeviceNode TextDeviceNode points to the text representation of a device 325 node. Conversion starts with the first character and continues 326 until the first non-device node character. 327 328 @return A pointer to the EFI device node or NULL if TextDeviceNode is NULL or there was 329 insufficient memory or text unsupported. 330 331 **/ 332 EFI_DEVICE_PATH_PROTOCOL * 333 EFIAPI 334 ConvertTextToDeviceNode ( 335 IN CONST CHAR16 *TextDeviceNode 336 ) 337 { 338 return UefiDevicePathLibConvertTextToDeviceNode (TextDeviceNode); 339 } 340 341 /** 342 Convert text to the binary representation of a device path. 343 344 345 @param TextDevicePath TextDevicePath points to the text representation of a device 346 path. Conversion starts with the first character and continues 347 until the first non-device node character. 348 349 @return A pointer to the allocated device path or NULL if TextDeviceNode is NULL or 350 there was insufficient memory. 351 352 **/ 353 EFI_DEVICE_PATH_PROTOCOL * 354 EFIAPI 355 ConvertTextToDevicePath ( 356 IN CONST CHAR16 *TextDevicePath 357 ) 358 { 359 return UefiDevicePathLibConvertTextToDevicePath (TextDevicePath); 360 } 361