+++ /dev/null
-/** @file\r
- Device Path services. The thing to remember is device paths are built out of\r
- nodes. The device path is terminated by an end node that is length\r
- sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL)\r
- all over this file.\r
-\r
- The only place where multi-instance device paths are supported is in\r
- environment varibles. Multi-instance device paths should never be placed\r
- on a Handle.\r
-\r
- Copyright (c) 2006, Intel Corporation \r
- All rights reserved. This program and the accompanying materials \r
- are licensed and made available under the terms and conditions of the BSD License \r
- which accompanies this distribution. The full text of the license may be found at \r
- http://opensource.org/licenses/bsd-license.php \r
-\r
- THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
- WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
-\r
- Module Name: UefiDevicePathLib.c\r
-\r
-**/\r
-\r
-/**\r
- Returns the size of a device path in bytes.\r
-\r
- This function returns the size, in bytes, of the device path data structure specified by\r
- DevicePath including the end of device path node. If DevicePath is NULL, then 0 is returned.\r
-\r
- @param DevicePath A pointer to a device path data structure.\r
-\r
- @return The size of a device path in bytes.\r
-\r
-**/\r
-UINTN\r
-EFIAPI\r
-GetDevicePathSize (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath\r
- )\r
-{\r
- CONST EFI_DEVICE_PATH_PROTOCOL *Start;\r
-\r
- if (DevicePath == NULL) {\r
- return 0;\r
- }\r
-\r
- //\r
- // Search for the end of the device path structure\r
- //\r
- Start = DevicePath;\r
- while (!EfiIsDevicePathEnd (DevicePath)) {\r
- DevicePath = EfiNextDevicePathNode (DevicePath);\r
- }\r
-\r
- //\r
- // Compute the size and add back in the size of the end device path structure\r
- //\r
- return ((UINTN) DevicePath - (UINTN) Start) + sizeof (EFI_DEVICE_PATH_PROTOCOL);\r
-}\r
-\r
-/**\r
- Creates a new device path by appending a second device path to a first device path.\r
-\r
- This function allocates space for a new copy of the device path specified by DevicePath. If\r
- DevicePath is NULL, then NULL is returned. If the memory is successfully allocated, then the\r
- contents of DevicePath are copied to the newly allocated buffer, and a pointer to that buffer\r
- is returned. Otherwise, NULL is returned. \r
- \r
- @param DevicePath A pointer to a device path data structure.\r
-\r
- @return A pointer to the duplicated device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-DuplicateDevicePath (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *NewDevicePath;\r
- UINTN Size;\r
-\r
- //\r
- // Compute the size\r
- //\r
- Size = GetDevicePathSize (DevicePath);\r
- if (Size == 0) {\r
- return NULL;\r
- }\r
-\r
- //\r
- // Allocate space for duplicate device path\r
- //\r
- NewDevicePath = AllocateCopyPool (Size, DevicePath);\r
-\r
- return NewDevicePath;\r
-}\r
-\r
-/**\r
- Creates a new device path by appending a second device path to a first device path.\r
-\r
- This function creates a new device path by appending a copy of SecondDevicePath to a copy of\r
- FirstDevicePath in a newly allocated buffer. Only the end-of-device-path device node from\r
- SecondDevicePath is retained. The newly created device path is returned. \r
- If FirstDevicePath is NULL, then it is ignored, and a duplicate of SecondDevicePath is returned. \r
- If SecondDevicePath is NULL, then it is ignored, and a duplicate of FirstDevicePath is returned. \r
- If both FirstDevicePath and SecondDevicePath are NULL, then NULL is returned. \r
- If there is not enough memory for the newly allocated buffer, then NULL is returned.\r
- The memory for the new device path is allocated from EFI boot services memory. It is the\r
- responsibility of the caller to free the memory allocated.\r
-\r
- @param FirstDevicePath A pointer to a device path data structure.\r
- @param SecondDevicePath A pointer to a device path data structure.\r
-\r
- @return A pointer to the new device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-AppendDevicePath (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *FirstDevicePath, OPTIONAL\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *SecondDevicePath OPTIONAL\r
- )\r
-{\r
- UINTN Size;\r
- UINTN Size1;\r
- UINTN Size2;\r
- EFI_DEVICE_PATH_PROTOCOL *NewDevicePath;\r
- EFI_DEVICE_PATH_PROTOCOL *DevicePath2;\r
-\r
- //\r
- // If there's only 1 path, just duplicate it.\r
- //\r
- if (FirstDevicePath == NULL) {\r
- return DuplicateDevicePath (SecondDevicePath);\r
- }\r
-\r
- if (SecondDevicePath == NULL) {\r
- return DuplicateDevicePath (FirstDevicePath);\r
- }\r
-\r
- //\r
- // Allocate space for the combined device path. It only has one end node of\r
- // length EFI_DEVICE_PATH_PROTOCOL.\r
- //\r
- Size1 = GetDevicePathSize (FirstDevicePath);\r
- Size2 = GetDevicePathSize (SecondDevicePath);\r
- Size = Size1 + Size2 - sizeof (EFI_DEVICE_PATH_PROTOCOL);\r
-\r
- NewDevicePath = AllocatePool (Size);\r
-\r
- if (NewDevicePath != NULL) {\r
- NewDevicePath = CopyMem (NewDevicePath, FirstDevicePath, Size1);\r
- //\r
- // Over write FirstDevicePath EndNode and do the copy\r
- //\r
- DevicePath2 = (EFI_DEVICE_PATH_PROTOCOL *) ((CHAR8 *) NewDevicePath +\r
- (Size1 - sizeof (EFI_DEVICE_PATH_PROTOCOL)));\r
- CopyMem (DevicePath2, SecondDevicePath, Size2);\r
- }\r
-\r
- return NewDevicePath;\r
-}\r
-\r
-/**\r
- Creates a new path by appending the device node to the device path.\r
-\r
- This function creates a new device path by appending a copy of the device node specified by\r
- DevicePathNode to a copy of the device path specified by DevicePath in an allocated buffer.\r
- The end-of-device-path device node is moved after the end of the appended device node.\r
- If DevicePath is NULL, then NULL is returned.\r
- If DevicePathNode is NULL, then NULL is returned.\r
- If there is not enough memory to allocate space for the new device path, then NULL is returned. \r
- The memory is allocated from EFI boot services memory. It is the responsibility of the caller to\r
- free the memory allocated.\r
-\r
- @param DevicePath A pointer to a device path data structure.\r
- @param DevicePathNode A pointer to a single device path node.\r
-\r
- @return A pointer to the new device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-AppendDevicePathNode (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathNode OPTIONAL\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *TempDevicePath;\r
- EFI_DEVICE_PATH_PROTOCOL *NextNode;\r
- EFI_DEVICE_PATH_PROTOCOL *NewDevicePath;\r
- UINTN NodeLength;\r
-\r
- if (DevicePath == NULL || DevicePathNode == NULL) {\r
- return NULL;\r
- }\r
- //\r
- // Build a Node that has a terminator on it\r
- //\r
- NodeLength = DevicePathNodeLength (DevicePathNode);\r
-\r
- TempDevicePath = AllocatePool (NodeLength + sizeof (EFI_DEVICE_PATH_PROTOCOL));\r
- if (TempDevicePath == NULL) {\r
- return NULL;\r
- }\r
- TempDevicePath = CopyMem (TempDevicePath, DevicePathNode, NodeLength);\r
- //\r
- // Add and end device path node to convert Node to device path\r
- //\r
- NextNode = NextDevicePathNode (TempDevicePath);\r
- SetDevicePathEndNode (NextNode);\r
- //\r
- // Append device paths\r
- //\r
- NewDevicePath = AppendDevicePath (DevicePath, TempDevicePath);\r
-\r
- FreePool (TempDevicePath);\r
-\r
- return NewDevicePath;\r
-}\r
-\r
-/**\r
- Creates a new device path by appending the specified device path instance to the specified device\r
- path.\r
- \r
- This function creates a new device path by appending a copy of the device path instance specified\r
- by DevicePathInstance to a copy of the device path secified by DevicePath in a allocated buffer.\r
- The end-of-device-path device node is moved after the end of the appended device path instance\r
- and a new end-of-device-path-instance node is inserted between. \r
- If DevicePath is NULL, then a copy if DevicePathInstance is returned.\r
- If DevicePathInstance is NULL, then NULL is returned.\r
- If there is not enough memory to allocate space for the new device path, then NULL is returned. \r
- The memory is allocated from EFI boot services memory. It is the responsibility of the caller to\r
- free the memory allocated.\r
- \r
- @param DevicePath A pointer to a device path data structure.\r
- @param DevicePathInstance A pointer to a device path instance.\r
-\r
- @return A pointer to the new device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-AppendDevicePathInstance (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance OPTIONAL\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *NewDevicePath;\r
- EFI_DEVICE_PATH_PROTOCOL *TempDevicePath;\r
- UINTN SrcSize;\r
- UINTN InstanceSize;\r
-\r
- if (DevicePath == NULL) {\r
- return DuplicateDevicePath (DevicePathInstance);\r
- }\r
-\r
- if (DevicePathInstance == NULL) {\r
- return NULL;\r
- }\r
-\r
- SrcSize = GetDevicePathSize (DevicePath);\r
- InstanceSize = GetDevicePathSize (DevicePathInstance);\r
-\r
- NewDevicePath = AllocatePool (SrcSize + InstanceSize);\r
- if (NewDevicePath != NULL) {\r
- \r
- TempDevicePath = CopyMem (NewDevicePath, DevicePath, SrcSize);;\r
- \r
- while (!IsDevicePathEnd (TempDevicePath)) {\r
- TempDevicePath = NextDevicePathNode (TempDevicePath);\r
- }\r
- \r
- TempDevicePath->SubType = END_INSTANCE_DEVICE_PATH_SUBTYPE;\r
- TempDevicePath = NextDevicePathNode (TempDevicePath);\r
- CopyMem (TempDevicePath, DevicePathInstance, InstanceSize);\r
- }\r
-\r
- return NewDevicePath;\r
-}\r
-\r
-/**\r
- Creates a copy of the current device path instance and returns a pointer to the next device path\r
- instance.\r
-\r
- This function creates a copy of the current device path instance. It also updates DevicePath to\r
- point to the next device path instance in the device path (or NULL if no more) and updates Size\r
- to hold the size of the device path instance copy.\r
- If DevicePath is NULL, then NULL is returned.\r
- If there is not enough memory to allocate space for the new device path, then NULL is returned. \r
- The memory is allocated from EFI boot services memory. It is the responsibility of the caller to\r
- free the memory allocated.\r
- If Size is NULL, then ASSERT().\r
- \r
- @param DevicePath On input, this holds the pointer to the current device path\r
- instance. On output, this holds the pointer to the next device\r
- path instance or NULL if there are no more device path\r
- instances in the device path pointer to a device path data\r
- structure.\r
- @param Size On output, this holds the size of the device path instance, in\r
- bytes or zero, if DevicePath is NULL.\r
-\r
- @return A pointer to the current device path instance.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-GetNextDevicePathInstance (\r
- IN OUT EFI_DEVICE_PATH_PROTOCOL **DevicePath,\r
- OUT UINTN *Size\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *DevPath;\r
- EFI_DEVICE_PATH_PROTOCOL *ReturnValue;\r
- UINT8 Temp;\r
-\r
- ASSERT (Size != NULL);\r
-\r
- if (DevicePath == NULL || *DevicePath == NULL) {\r
- *Size = 0;\r
- return NULL;\r
- }\r
-\r
- //\r
- // Find the end of the device path instance\r
- //\r
- DevPath = *DevicePath;\r
- while (!IsDevicePathEndType (DevPath)) {\r
- DevPath = NextDevicePathNode (DevPath);\r
- }\r
-\r
- //\r
- // Compute the size of the device path instance\r
- //\r
- *Size = ((UINTN) DevPath - (UINTN) (*DevicePath)) + sizeof (EFI_DEVICE_PATH_PROTOCOL);\r
- \r
- //\r
- // Make a copy and return the device path instance\r
- //\r
- Temp = DevPath->SubType;\r
- DevPath->SubType = END_ENTIRE_DEVICE_PATH_SUBTYPE;\r
- ReturnValue = DuplicateDevicePath (*DevicePath);\r
- DevPath->SubType = Temp;\r
-\r
- //\r
- // If DevPath is the end of an entire device path, then another instance\r
- // does not follow, so *DevicePath is set to NULL.\r
- //\r
- if (DevicePathSubType (DevPath) == END_ENTIRE_DEVICE_PATH_SUBTYPE) {\r
- *DevicePath = NULL;\r
- } else {\r
- *DevicePath = NextDevicePathNode (DevPath);\r
- }\r
-\r
- return ReturnValue;\r
-}\r
-\r
-/**\r
- Creates a copy of the current device path instance and returns a pointer to the next device path\r
- instance.\r
-\r
- This function creates a new device node in a newly allocated buffer of size NodeLength and\r
- initializes the device path node header with NodeType and NodeSubType. The new device path node\r
- is returned.\r
- If NodeLength is smaller than a device path header, then NULL is returned. \r
- If there is not enough memory to allocate space for the new device path, then NULL is returned. \r
- The memory is allocated from EFI boot services memory. It is the responsibility of the caller to\r
- free the memory allocated.\r
-\r
- @param NodeType The device node type for the new device node.\r
- @param NodeSubType The device node sub-type for the new device node.\r
- @param NodeLength The length of the new device node.\r
-\r
- @return The new device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-CreateDeviceNode (\r
- IN UINT8 NodeType,\r
- IN UINT8 NodeSubType,\r
- IN UINT16 NodeLength\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *DevicePath;\r
-\r
- if (NodeLength < sizeof (EFI_DEVICE_PATH_PROTOCOL)) {\r
- //\r
- // NodeLength is less than the size of the header.\r
- //\r
- return NULL;\r
- }\r
- \r
- DevicePath = AllocatePool (NodeLength);\r
- if (DevicePath != NULL) {\r
- DevicePath->Type = NodeType;\r
- DevicePath->SubType = NodeSubType;\r
- SetDevicePathNodeLength (DevicePath, NodeLength);\r
- }\r
-\r
- return DevicePath;\r
-}\r
-\r
-/**\r
- Determines if a device path is single or multi-instance.\r
-\r
- This function returns TRUE if the device path specified by DevicePath is multi-instance.\r
- Otherwise, FALSE is returned. If DevicePath is NULL, then FALSE is returned.\r
-\r
- @param DevicePath A pointer to a device path data structure.\r
-\r
- @retval TRUE DevicePath is multi-instance.\r
- @retval FALSE DevicePath is not multi-instance or DevicePath is NULL.\r
-\r
-**/\r
-BOOLEAN\r
-EFIAPI\r
-IsDevicePathMultiInstance (\r
- IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath\r
- )\r
-{\r
- CONST EFI_DEVICE_PATH_PROTOCOL *Node;\r
-\r
- if (DevicePath == NULL) {\r
- return FALSE;\r
- }\r
-\r
- Node = DevicePath;\r
- while (!EfiIsDevicePathEnd (Node)) {\r
- if (EfiIsDevicePathEndInstance (Node)) {\r
- return TRUE;\r
- }\r
-\r
- Node = EfiNextDevicePathNode (Node);\r
- }\r
-\r
- return FALSE;\r
-}\r
-\r
-\r
-/**\r
- Retrieves the device path protocol from a handle.\r
-\r
- This function returns the device path protocol from the handle specified by Handle. If Handle is\r
- NULL or Handle does not contain a device path protocol, then NULL is returned.\r
- \r
- @param Handle The handle from which to retrieve the device path protocol.\r
-\r
- @return The device path protocol from the handle specified by Handle.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-DevicePathFromHandle (\r
- IN EFI_HANDLE Handle\r
- )\r
-{\r
- EFI_DEVICE_PATH_PROTOCOL *DevicePath;\r
- EFI_STATUS Status;\r
-\r
- Status = gBS->HandleProtocol (\r
- Handle,\r
- &gEfiDevicePathProtocolGuid,\r
- (VOID *) &DevicePath\r
- );\r
- if (EFI_ERROR (Status)) {\r
- DevicePath = NULL;\r
- }\r
- return DevicePath;\r
-}\r
-\r
-/**\r
- Allocates a device path for a file and appends it to an existing device path.\r
-\r
- If Device is a valid device handle that contains a device path protocol, then a device path for\r
- the file specified by FileName is allocated and appended to the device path associated with the\r
- handle Device. The allocated device path is returned. If Device is NULL or Device is a handle\r
- that does not support the device path protocol, then a device path containing a single device\r
- path node for the file specified by FileName is allocated and returned.\r
- If FileName is NULL, then ASSERT().\r
-\r
- @param Device A pointer to a device handle. This parameter is optional and\r
- may be NULL.\r
- @param FileName A pointer to a Null-terminated Unicode string.\r
-\r
- @return The allocated device path.\r
-\r
-**/\r
-EFI_DEVICE_PATH_PROTOCOL *\r
-EFIAPI\r
-FileDevicePath (\r
- IN EFI_HANDLE Device, OPTIONAL\r
- IN CONST CHAR16 *FileName\r
- )\r
-{\r
- UINTN Size;\r
- FILEPATH_DEVICE_PATH *FilePath;\r
- EFI_DEVICE_PATH_PROTOCOL *DevicePath;\r
- EFI_DEVICE_PATH_PROTOCOL *FileDevicePath;\r
-\r
- DevicePath = NULL;\r
-\r
- Size = StrSize (FileName);\r
- FileDevicePath = AllocatePool (Size + SIZE_OF_FILEPATH_DEVICE_PATH + EFI_END_DEVICE_PATH_LENGTH);\r
- if (FileDevicePath != NULL) {\r
- FilePath = (FILEPATH_DEVICE_PATH *) FileDevicePath;\r
- FilePath->Header.Type = MEDIA_DEVICE_PATH;\r
- FilePath->Header.SubType = MEDIA_FILEPATH_DP;\r
- CopyMem (&FilePath->PathName, FileName, Size);\r
- SetDevicePathNodeLength (&FilePath->Header, Size + SIZE_OF_FILEPATH_DEVICE_PATH);\r
- SetDevicePathEndNode (NextDevicePathNode (&FilePath->Header));\r
-\r
- if (Device != NULL) {\r
- DevicePath = DevicePathFromHandle (Device);\r
- }\r
-\r
- DevicePath = AppendDevicePath (DevicePath, FileDevicePath);\r
- FreePool (FileDevicePath);\r
- }\r
-\r
- return DevicePath;\r
-}\r
-\r
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