Add 4 APIs to DevicePathLib: ConvertDeviceNodeToText, ConvertDevicePathToText, ConvertTextToDeviceNode and ConvertTextToDevicePath.

Add a new instance of DevicePathLib which tries to locate the protocol and if it's not found, it uses the internal functions.

Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14504 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 484 insertions, 0 deletions

diff --git a/MdePkg/Library/UefiDevicePathLib/UefiDevicePathLibOptionalDevicePathProtocol.c b/MdePkg/Library/UefiDevicePathLib/UefiDevicePathLibOptionalDevicePathProtocol.c
new file mode 100644
index 0000000000..9580e397ff
--- /dev/null
+++ b/MdePkg/Library/UefiDevicePathLib/UefiDevicePathLibOptionalDevicePathProtocol.c
@@ -0,0 +1,484 @@
+/** @file

+  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.

+

+  Copyright (c) 2013, Intel Corporation. All rights reserved.<BR>

+  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.             

+

+**/

+

+

+#include "UefiDevicePathLib.h"

+

+GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_UTILITIES_PROTOCOL *mDevicePathLibDevicePathUtilities = NULL;

+GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_TO_TEXT_PROTOCOL   *mDevicePathLibDevicePathToText    = NULL;

+GLOBAL_REMOVE_IF_UNREFERENCED EFI_DEVICE_PATH_FROM_TEXT_PROTOCOL *mDevicePathLibDevicePathFromText  = NULL;

+

+/**

+  The constructor function caches the pointer to DevicePathUtilites protocol,

+  DevicePathToText protocol and DevicePathFromText protocol.

+  

+  The constructor function locates these three protocols from protocol database.

+  It will caches the pointer to local protocol instance if that operation fails

+  and it will always return EFI_SUCCESS. 

+

+  @param  ImageHandle   The firmware allocated handle for the EFI image.

+  @param  SystemTable   A pointer to the EFI System Table.

+  

+  @retval EFI_SUCCESS   The constructor always returns EFI_SUCCESS.

+

+**/

+EFI_STATUS

+EFIAPI

+UefiDevicePathLibOptionalDevicePathProtocolConstructor (

+  IN      EFI_HANDLE                ImageHandle,

+  IN      EFI_SYSTEM_TABLE          *SystemTable

+  )

+{

+  EFI_STATUS                        Status;

+

+  Status = gBS->LocateProtocol (

+                  &gEfiDevicePathUtilitiesProtocolGuid,

+                  NULL,

+                  (VOID**) &mDevicePathLibDevicePathUtilities

+                  );

+  ASSERT_EFI_ERROR (Status);

+  ASSERT (mDevicePathLibDevicePathUtilities != NULL);

+  return Status;

+}

+

+/**

+  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 or invalid, then 0 is returned.

+

+  @param  DevicePath  A pointer to a device path data structure.

+

+  @retval 0           If DevicePath is NULL or invalid.

+  @retval Others      The size of a device path in bytes.

+

+**/

+UINTN

+EFIAPI

+GetDevicePathSize (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->GetDevicePathSize (DevicePath);

+  } else {

+    return UefiDevicePathLibGetDevicePathSize (DevicePath);

+  }

+}

+

+/**

+  Creates a new copy of an existing 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.  

+  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  DevicePath    A pointer to a device path data structure.

+

+  @retval NULL          DevicePath is NULL or invalid.

+  @retval Others        A pointer to the duplicated device path.

+  

+**/

+EFI_DEVICE_PATH_PROTOCOL *

+EFIAPI

+DuplicateDevicePath (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->DuplicateDevicePath (DevicePath);

+  } else {

+    return UefiDevicePathLibDuplicateDevicePath (DevicePath);

+  }

+}

+

+/**

+  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 a copy of an end-of-device-path 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.

+  

+  @retval NULL      If there is not enough memory for the newly allocated buffer.

+  @retval NULL      If FirstDevicePath or SecondDevicePath is invalid.

+  @retval Others    A pointer to the new device path if success.

+                    Or a copy an end-of-device-path if both FirstDevicePath and SecondDevicePath are NULL.

+

+**/

+EFI_DEVICE_PATH_PROTOCOL *

+EFIAPI

+AppendDevicePath (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *FirstDevicePath,  OPTIONAL

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *SecondDevicePath  OPTIONAL

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->AppendDevicePath (FirstDevicePath, SecondDevicePath);

+  } else {

+    return UefiDevicePathLibAppendDevicePath (FirstDevicePath, SecondDevicePath);

+  }

+}

+

+/**

+  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 DevicePathNode is NULL then a copy of DevicePath is returned.

+  If DevicePath is NULL then a copy of DevicePathNode, followed by an end-of-device 

+  path device node is returned.

+  If both DevicePathNode and DevicePath are NULL then a copy of an end-of-device-path 

+  device node 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.

+

+  @retval NULL      If there is not enough memory for the new device path.

+  @retval Others    A pointer to the new device path if success.

+                    A copy of DevicePathNode followed by an end-of-device-path node 

+                    if both FirstDevicePath and SecondDevicePath are NULL.

+                    A copy of an end-of-device-path node if both FirstDevicePath 

+                    and SecondDevicePath are NULL.

+

+**/

+EFI_DEVICE_PATH_PROTOCOL *

+EFIAPI

+AppendDevicePathNode (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath,     OPTIONAL

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathNode  OPTIONAL

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->AppendDeviceNode (DevicePath, DevicePathNode);

+  } else {

+    return UefiDevicePathLibAppendDevicePathNode (DevicePath, DevicePathNode);

+  }

+}

+

+/**

+  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 specified 

+  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 DevicePath or DevicePathInstance is invalid, 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

+AppendDevicePathInstance (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath,        OPTIONAL

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePathInstance OPTIONAL

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->AppendDevicePathInstance (DevicePath, DevicePathInstance);

+  } else {

+    return UefiDevicePathLibAppendDevicePathInstance (DevicePath, DevicePathInstance);

+  }

+}

+

+/**

+  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 DevicePath points to a invalid device path, 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

+GetNextDevicePathInstance (

+  IN OUT EFI_DEVICE_PATH_PROTOCOL    **DevicePath,

+  OUT UINTN                          *Size

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->GetNextDevicePathInstance (DevicePath, Size);

+  } else {

+    return UefiDevicePathLibGetNextDevicePathInstance (DevicePath, Size);

+  }

+}

+

+/**

+  Creates a device node.

+

+  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

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->CreateDeviceNode (NodeType, NodeSubType, NodeLength);

+  } else {

+    return UefiDevicePathLibCreateDeviceNode (NodeType, NodeSubType, NodeLength);

+  }

+}

+

+/**

+  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 or invalid, 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 or invalid.

+

+**/

+BOOLEAN

+EFIAPI

+IsDevicePathMultiInstance (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DevicePath

+  )

+{

+  if (mDevicePathLibDevicePathUtilities != NULL) {

+    return mDevicePathLibDevicePathUtilities->IsDevicePathMultiInstance (DevicePath);

+  } else {

+    return UefiDevicePathLibIsDevicePathMultiInstance (DevicePath);

+  }

+}

+

+/**

+  Locate and return the protocol instance identified by the ProtocolGuid.

+

+  @param ProtocolGuid     The GUID of the protocol.

+

+  @return A pointer to the protocol instance or NULL when absent.

+**/

+VOID *

+UefiDevicePathLibLocateProtocol (

+  EFI_GUID                         *ProtocolGuid

+  )

+{

+  EFI_STATUS Status;

+  VOID       *Protocol;

+  Status = gBS->LocateProtocol (

+                  ProtocolGuid,

+                  NULL,

+                  (VOID**) &Protocol

+                  );

+  if (EFI_ERROR (Status)) {

+    return NULL;

+  } else {

+    return Protocol;

+  }

+}

+

+/**

+  Converts a device node to its string representation.

+

+  @param DeviceNode        A Pointer to the device node to be converted.

+  @param DisplayOnly       If DisplayOnly is TRUE, then the shorter text representation

+                           of the display node is used, where applicable. If DisplayOnly

+                           is FALSE, then the longer text representation of the display node

+                           is used.

+  @param AllowShortcuts    If AllowShortcuts is TRUE, then the shortcut forms of text

+                           representation for a device node can be used, where applicable.

+

+  @return A pointer to the allocated text representation of the device node or NULL if DeviceNode

+          is NULL or there was insufficient memory.

+

+**/

+CHAR16 *

+EFIAPI

+ConvertDeviceNodeToText (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL  *DeviceNode,

+  IN BOOLEAN                         DisplayOnly,

+  IN BOOLEAN                         AllowShortcuts

+  )

+{

+  if (mDevicePathLibDevicePathToText == NULL) {

+    mDevicePathLibDevicePathToText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathToTextProtocolGuid);

+  }

+  if (mDevicePathLibDevicePathToText != NULL) {

+    return mDevicePathLibDevicePathToText->ConvertDeviceNodeToText (DeviceNode, DisplayOnly, AllowShortcuts);

+  }

+

+  return UefiDevicePathLibConvertDeviceNodeToText (DeviceNode, DisplayOnly, AllowShortcuts);

+}

+

+/**

+  Converts a device path to its text representation.

+

+  @param DevicePath      A Pointer to the device to be converted.

+  @param DisplayOnly     If DisplayOnly is TRUE, then the shorter text representation

+                         of the display node is used, where applicable. If DisplayOnly

+                         is FALSE, then the longer text representation of the display node

+                         is used.

+  @param AllowShortcuts  If AllowShortcuts is TRUE, then the shortcut forms of text

+                         representation for a device node can be used, where applicable.

+

+  @return A pointer to the allocated text representation of the device path or

+          NULL if DeviceNode is NULL or there was insufficient memory.

+

+**/

+CHAR16 *

+EFIAPI

+ConvertDevicePathToText (

+  IN CONST EFI_DEVICE_PATH_PROTOCOL   *DevicePath,

+  IN BOOLEAN                          DisplayOnly,

+  IN BOOLEAN                          AllowShortcuts

+  )

+{

+  if (mDevicePathLibDevicePathToText == NULL) {

+    mDevicePathLibDevicePathToText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathToTextProtocolGuid);

+  }

+  if (mDevicePathLibDevicePathToText != NULL) {

+    return mDevicePathLibDevicePathToText->ConvertDevicePathToText (DevicePath, DisplayOnly, AllowShortcuts);

+  }

+

+  return UefiDevicePathLibConvertDevicePathToText (DevicePath, DisplayOnly, AllowShortcuts);

+}

+

+/**

+  Convert text to the binary representation of a device node.

+

+  @param TextDeviceNode  TextDeviceNode points to the text representation of a device

+                         node. Conversion starts with the first character and continues

+                         until the first non-device node character.

+

+  @return A pointer to the EFI device node or NULL if TextDeviceNode is NULL or there was

+          insufficient memory or text unsupported.

+

+**/

+EFI_DEVICE_PATH_PROTOCOL *

+EFIAPI

+ConvertTextToDeviceNode (

+  IN CONST CHAR16 *TextDeviceNode

+  )

+{

+  if (mDevicePathLibDevicePathFromText == NULL) {

+    mDevicePathLibDevicePathFromText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathFromTextProtocolGuid);

+  }

+  if (mDevicePathLibDevicePathFromText != NULL) {

+    return mDevicePathLibDevicePathFromText->ConvertTextToDeviceNode (TextDeviceNode);

+  }

+

+  return UefiDevicePathLibConvertTextToDeviceNode (TextDeviceNode);

+}

+

+/**

+  Convert text to the binary representation of a device path.

+

+

+  @param TextDevicePath  TextDevicePath points to the text representation of a device

+                         path. Conversion starts with the first character and continues

+                         until the first non-device node character.

+

+  @return A pointer to the allocated device path or NULL if TextDeviceNode is NULL or

+          there was insufficient memory.

+

+**/

+EFI_DEVICE_PATH_PROTOCOL *

+EFIAPI

+ConvertTextToDevicePath (

+  IN CONST CHAR16 *TextDevicePath

+  )

+{

+  if (mDevicePathLibDevicePathFromText == NULL) {

+    mDevicePathLibDevicePathFromText = UefiDevicePathLibLocateProtocol (&gEfiDevicePathFromTextProtocolGuid);

+  }

+  if (mDevicePathLibDevicePathFromText != NULL) {

+    return mDevicePathLibDevicePathFromText->ConvertTextToDevicePath (TextDevicePath);

+  }

+

+  return UefiDevicePathLibConvertTextToDevicePath (TextDevicePath);

+}

+