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Diffstat (limited to 'EDK/Foundation/Library/EdkIIGlueLib/Library/UefiDevicePathLib/UefiDevicePathLib.c')
| -rw-r--r-- | EDK/Foundation/Library/EdkIIGlueLib/Library/UefiDevicePathLib/UefiDevicePathLib.c | 533 |
1 files changed, 533 insertions, 0 deletions
diff --git a/EDK/Foundation/Library/EdkIIGlueLib/Library/UefiDevicePathLib/UefiDevicePathLib.c b/EDK/Foundation/Library/EdkIIGlueLib/Library/UefiDevicePathLib/UefiDevicePathLib.c new file mode 100644 index 0000000..a7f22bb --- /dev/null +++ b/EDK/Foundation/Library/EdkIIGlueLib/Library/UefiDevicePathLib/UefiDevicePathLib.c @@ -0,0 +1,533 @@ +/*++ + +Copyright (c) 2004 - 2006, Intel Corporation +All rights reserved. This program and the accompanying materials +are licensed and made available under the terms and conditions of the BSD License +which accompanies this distribution. The full text of the license may be found at +http://opensource.org/licenses/bsd-license.php + +THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, +WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. + + +Module Name: + + UefiDevicePathLib.c + +Abstract: + + Device Path services. The thing to remember is device paths are built out of + nodes. The device path is terminated by an end node that is length + sizeof(EFI_DEVICE_PATH_PROTOCOL). That would be why there is sizeof(EFI_DEVICE_PATH_PROTOCOL) + all over this file. + + The only place where multi-instance device paths are supported is in + environment varibles. Multi-instance device paths should never be placed + on a Handle. + +--*/ + +#include "EdkIIGlueUefi.h" +#include "Library\EdkIIGlueMemoryAllocationLib.h" + +/** + Returns the size of a device path in bytes. + + This function returns the size, in bytes, of the device path data structure specified by + DevicePath including the end of device path node. If DevicePath is NULL, then 0 is returned. + + @param DevicePath A pointer to a device path data structure. + + @return The size of a device path in bytes. + +**/ +UINTN +EFIAPI +GlueGetDevicePathSize ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath + ) +{ + CONST EFI_DEVICE_PATH_PROTOCOL *Start; + + if (DevicePath == NULL) { + return 0; + } + + // + // Search for the end of the device path structure + // + Start = DevicePath; + while (!EfiIsDevicePathEnd (DevicePath)) { + DevicePath = EfiNextDevicePathNode (DevicePath); + } + + // + // Compute the size and add back in the size of the end device path structure + // + return ((UINTN) DevicePath - (UINTN) Start) + sizeof (EFI_DEVICE_PATH_PROTOCOL); +} + +/** + Creates a new device path by appending a second device path to a first device path. + + This function allocates space for a new copy of the device path specified by DevicePath. If + DevicePath is NULL, then NULL is returned. If the memory is successfully allocated, then the + contents of DevicePath are copied to the newly allocated buffer, and a pointer to that buffer + is returned. Otherwise, NULL is returned. + + @param DevicePath A pointer to a device path data structure. + + @return A pointer to the duplicated device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueDuplicateDevicePath ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath + ) +{ + EFI_DEVICE_PATH_PROTOCOL *NewDevicePath; + UINTN Size; + + // + // Compute the size + // + Size = GetDevicePathSize (DevicePath); + if (Size == 0) { + return NULL; + } + + // + // Allocate space for duplicate device path + // + NewDevicePath = AllocateCopyPool (Size, DevicePath); + + return NewDevicePath; +} + +/** + Creates a new device path by appending a second device path to a first device path. + + This function creates a new device path by appending a copy of SecondDevicePath to a copy of + FirstDevicePath in a newly allocated buffer. Only the end-of-device-path device node from + SecondDevicePath is retained. The newly created device path is returned. + If FirstDevicePath is NULL, then it is ignored, and a duplicate of SecondDevicePath is returned. + If SecondDevicePath is NULL, then it is ignored, and a duplicate of FirstDevicePath is returned. + If both FirstDevicePath and SecondDevicePath are NULL, then NULL is returned. + If there is not enough memory for the newly allocated buffer, then NULL is returned. + The memory for the new device path is allocated from EFI boot services memory. It is the + responsibility of the caller to free the memory allocated. + + @param FirstDevicePath A pointer to a device path data structure. + @param SecondDevicePath A pointer to a device path data structure. + + @return A pointer to the new device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueAppendDevicePath ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *FirstDevicePath, OPTIONAL + IN CONST EFI_DEVICE_PATH_PROTOCOL *SecondDevicePath OPTIONAL + ) +{ + UINTN Size; + UINTN Size1; + UINTN Size2; + EFI_DEVICE_PATH_PROTOCOL *NewDevicePath; + EFI_DEVICE_PATH_PROTOCOL *DevicePath2; + + // + // If there's only 1 path, just duplicate it. + // + if (FirstDevicePath == NULL) { + return DuplicateDevicePath (SecondDevicePath); + } + + if (SecondDevicePath == NULL) { + return DuplicateDevicePath (FirstDevicePath); + } + + // + // Allocate space for the combined device path. It only has one end node of + // length EFI_DEVICE_PATH_PROTOCOL. + // + Size1 = GetDevicePathSize (FirstDevicePath); + Size2 = GetDevicePathSize (SecondDevicePath); + Size = Size1 + Size2 - sizeof (EFI_DEVICE_PATH_PROTOCOL); + + NewDevicePath = AllocatePool (Size); + + if (NewDevicePath != NULL) { + NewDevicePath = CopyMem (NewDevicePath, FirstDevicePath, Size1); + // + // Over write FirstDevicePath EndNode and do the copy + // + DevicePath2 = (EFI_DEVICE_PATH_PROTOCOL *) ((CHAR8 *) NewDevicePath + + (Size1 - sizeof (EFI_DEVICE_PATH_PROTOCOL))); + CopyMem (DevicePath2, SecondDevicePath, Size2); + } + + return NewDevicePath; +} + +/** + Creates a new path by appending the device node to the device path. + + This function creates a new device path by appending a copy of the device node specified by + DevicePathNode to a copy of the device path specified by DevicePath in an allocated buffer. + The end-of-device-path device node is moved after the end of the appended device node. + If DevicePath is NULL, then NULL is returned. + If DevicePathNode is NULL, then NULL is returned. + If there is not enough memory to allocate space for the new device path, then NULL is returned. + The memory is allocated from EFI boot services memory. It is the responsibility of the caller to + free the memory allocated. + + @param DevicePath A pointer to a device path data structure. + @param DevicePathNode A pointer to a single device path node. + + @return A pointer to the new device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueAppendDevicePathNode ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathNode OPTIONAL + ) +{ + EFI_DEVICE_PATH_PROTOCOL *TempDevicePath; + EFI_DEVICE_PATH_PROTOCOL *NextNode; + EFI_DEVICE_PATH_PROTOCOL *NewDevicePath; + UINTN NodeLength; + + if (DevicePath == NULL || DevicePathNode == NULL) { + return NULL; + } + // + // Build a Node that has a terminator on it + // + NodeLength = DevicePathNodeLength (DevicePathNode); + + TempDevicePath = AllocatePool (NodeLength + sizeof (EFI_DEVICE_PATH_PROTOCOL)); + if (TempDevicePath == NULL) { + return NULL; + } + TempDevicePath = CopyMem (TempDevicePath, DevicePathNode, NodeLength); + // + // Add and end device path node to convert Node to device path + // + NextNode = NextDevicePathNode (TempDevicePath); + SetDevicePathEndNode (NextNode); + // + // Append device paths + // + NewDevicePath = AppendDevicePath (DevicePath, TempDevicePath); + + FreePool (TempDevicePath); + + return NewDevicePath; +} + +/** + Creates a new device path by appending the specified device path instance to the specified device + path. + + This function creates a new device path by appending a copy of the device path instance specified + by DevicePathInstance to a copy of the device path secified by DevicePath in a allocated buffer. + The end-of-device-path device node is moved after the end of the appended device path instance + and a new end-of-device-path-instance node is inserted between. + If DevicePath is NULL, then a copy if DevicePathInstance is returned. + If DevicePathInstance is NULL, then NULL is returned. + If there is not enough memory to allocate space for the new device path, then NULL is returned. + The memory is allocated from EFI boot services memory. It is the responsibility of the caller to + free the memory allocated. + + @param DevicePath A pointer to a device path data structure. + @param DevicePathInstance A pointer to a device path instance. + + @return A pointer to the new device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueAppendDevicePathInstance ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath, OPTIONAL + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePathInstance OPTIONAL + ) +{ + EFI_DEVICE_PATH_PROTOCOL *NewDevicePath; + EFI_DEVICE_PATH_PROTOCOL *TempDevicePath; + UINTN SrcSize; + UINTN InstanceSize; + + if (DevicePath == NULL) { + return DuplicateDevicePath (DevicePathInstance); + } + + if (DevicePathInstance == NULL) { + return NULL; + } + + SrcSize = GetDevicePathSize (DevicePath); + InstanceSize = GetDevicePathSize (DevicePathInstance); + + NewDevicePath = AllocatePool (SrcSize + InstanceSize); + if (NewDevicePath != NULL) { + + TempDevicePath = CopyMem (NewDevicePath, DevicePath, SrcSize);; + + while (!IsDevicePathEnd (TempDevicePath)) { + TempDevicePath = NextDevicePathNode (TempDevicePath); + } + + TempDevicePath->SubType = END_INSTANCE_DEVICE_PATH_SUBTYPE; + TempDevicePath = NextDevicePathNode (TempDevicePath); + CopyMem (TempDevicePath, DevicePathInstance, InstanceSize); + } + + return NewDevicePath; +} + +/** + Creates a copy of the current device path instance and returns a pointer to the next device path + instance. + + This function creates a copy of the current device path instance. It also updates DevicePath to + point to the next device path instance in the device path (or NULL if no more) and updates Size + to hold the size of the device path instance copy. + If DevicePath is NULL, then NULL is returned. + If there is not enough memory to allocate space for the new device path, then NULL is returned. + The memory is allocated from EFI boot services memory. It is the responsibility of the caller to + free the memory allocated. + If Size is NULL, then ASSERT(). + + @param DevicePath On input, this holds the pointer to the current device path + instance. On output, this holds the pointer to the next device + path instance or NULL if there are no more device path + instances in the device path pointer to a device path data + structure. + @param Size On output, this holds the size of the device path instance, in + bytes or zero, if DevicePath is NULL. + + @return A pointer to the current device path instance. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueGetNextDevicePathInstance ( + IN OUT EFI_DEVICE_PATH_PROTOCOL **DevicePath, + OUT UINTN *Size + ) +{ + EFI_DEVICE_PATH_PROTOCOL *DevPath; + EFI_DEVICE_PATH_PROTOCOL *ReturnValue; + UINT8 Temp; + + ASSERT (Size != NULL); + + if (DevicePath == NULL || *DevicePath == NULL) { + *Size = 0; + return NULL; + } + + // + // Find the end of the device path instance + // + DevPath = *DevicePath; + while (!IsDevicePathEndType (DevPath)) { + DevPath = NextDevicePathNode (DevPath); + } + + // + // Compute the size of the device path instance + // + *Size = ((UINTN) DevPath - (UINTN) (*DevicePath)) + sizeof (EFI_DEVICE_PATH_PROTOCOL); + + // + // Make a copy and return the device path instance + // + Temp = DevPath->SubType; + DevPath->SubType = END_ENTIRE_DEVICE_PATH_SUBTYPE; + ReturnValue = DuplicateDevicePath (*DevicePath); + DevPath->SubType = Temp; + + // + // If DevPath is the end of an entire device path, then another instance + // does not follow, so *DevicePath is set to NULL. + // + if (DevicePathSubType (DevPath) == END_ENTIRE_DEVICE_PATH_SUBTYPE) { + *DevicePath = NULL; + } else { + *DevicePath = NextDevicePathNode (DevPath); + } + + return ReturnValue; +} + +/** + Creates a copy of the current device path instance and returns a pointer to the next device path + instance. + + This function creates a new device node in a newly allocated buffer of size NodeLength and + initializes the device path node header with NodeType and NodeSubType. The new device path node + is returned. + If NodeLength is smaller than a device path header, then NULL is returned. + If there is not enough memory to allocate space for the new device path, then NULL is returned. + The memory is allocated from EFI boot services memory. It is the responsibility of the caller to + free the memory allocated. + + @param NodeType The device node type for the new device node. + @param NodeSubType The device node sub-type for the new device node. + @param NodeLength The length of the new device node. + + @return The new device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +CreateDeviceNode ( + IN UINT8 NodeType, + IN UINT8 NodeSubType, + IN UINT16 NodeLength + ) +{ + EFI_DEVICE_PATH_PROTOCOL *DevicePath; + + if (NodeLength < sizeof (EFI_DEVICE_PATH_PROTOCOL)) { + // + // NodeLength is less than the size of the header. + // + return NULL; + } + + DevicePath = AllocatePool (NodeLength); + if (DevicePath != NULL) { + DevicePath->Type = NodeType; + DevicePath->SubType = NodeSubType; + SetDevicePathNodeLength (DevicePath, NodeLength); + } + + return DevicePath; +} + +/** + Determines if a device path is single or multi-instance. + + This function returns TRUE if the device path specified by DevicePath is multi-instance. + Otherwise, FALSE is returned. If DevicePath is NULL, then FALSE is returned. + + @param DevicePath A pointer to a device path data structure. + + @retval TRUE DevicePath is multi-instance. + @retval FALSE DevicePath is not multi-instance or DevicePath is NULL. + +**/ +BOOLEAN +EFIAPI +GlueIsDevicePathMultiInstance ( + IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath + ) +{ + CONST EFI_DEVICE_PATH_PROTOCOL *Node; + + if (DevicePath == NULL) { + return FALSE; + } + + Node = DevicePath; + while (!EfiIsDevicePathEnd (Node)) { + if (EfiIsDevicePathEndInstance (Node)) { + return TRUE; + } + + Node = EfiNextDevicePathNode (Node); + } + + return FALSE; +} + + +/** + Retrieves the device path protocol from a handle. + + This function returns the device path protocol from the handle specified by Handle. If Handle is + NULL or Handle does not contain a device path protocol, then NULL is returned. + + @param Handle The handle from which to retrieve the device path protocol. + + @return The device path protocol from the handle specified by Handle. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueDevicePathFromHandle ( + IN EFI_HANDLE Handle + ) +{ + EFI_DEVICE_PATH_PROTOCOL *DevicePath; + EFI_STATUS Status; + + Status = gBS->HandleProtocol ( + Handle, + &gEfiDevicePathProtocolGuid, + (VOID *) &DevicePath + ); + if (EFI_ERROR (Status)) { + DevicePath = NULL; + } + return DevicePath; +} + +/** + Allocates a device path for a file and appends it to an existing device path. + + If Device is a valid device handle that contains a device path protocol, then a device path for + the file specified by FileName is allocated and appended to the device path associated with the + handle Device. The allocated device path is returned. If Device is NULL or Device is a handle + that does not support the device path protocol, then a device path containing a single device + path node for the file specified by FileName is allocated and returned. + If FileName is NULL, then ASSERT(). + + @param Device A pointer to a device handle. This parameter is optional and + may be NULL. + @param FileName A pointer to a Null-terminated Unicode string. + + @return The allocated device path. + +**/ +EFI_DEVICE_PATH_PROTOCOL * +EFIAPI +GlueFileDevicePath ( + IN EFI_HANDLE Device, OPTIONAL + IN CONST CHAR16 *FileName + ) +{ + UINTN Size; + FILEPATH_DEVICE_PATH *FilePath; + EFI_DEVICE_PATH_PROTOCOL *DevicePath; + EFI_DEVICE_PATH_PROTOCOL *FileDevicePath; + + DevicePath = NULL; + + Size = StrSize (FileName); + FileDevicePath = AllocatePool (Size + SIZE_OF_FILEPATH_DEVICE_PATH + EFI_END_DEVICE_PATH_LENGTH); + if (FileDevicePath != NULL) { + FilePath = (FILEPATH_DEVICE_PATH *) FileDevicePath; + FilePath->Header.Type = MEDIA_DEVICE_PATH; + FilePath->Header.SubType = MEDIA_FILEPATH_DP; + CopyMem (&FilePath->PathName, FileName, Size); + SetDevicePathNodeLength (&FilePath->Header, Size + SIZE_OF_FILEPATH_DEVICE_PATH); + SetDevicePathEndNode (NextDevicePathNode (&FilePath->Header)); + + if (Device != NULL) { + DevicePath = DevicePathFromHandle (Device); + } + + DevicePath = AppendDevicePath (DevicePath, FileDevicePath); + FreePool (FileDevicePath); + } + + return DevicePath; +} + |