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      1 /** @file
      2   EFI Shell protocol as defined in the UEFI Shell 2.0 specification including errata.
      3 
      4   (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
      5   Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
      6   This program and the accompanying materials
      7   are licensed and made available under the terms and conditions of the BSD License
      8   which accompanies this distribution.  The full text of the license may be found at
      9   http://opensource.org/licenses/bsd-license.php
     10 
     11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
     12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
     13 
     14 **/
     15 
     16 #ifndef __EFI_SHELL_PROTOCOL_H__
     17 #define __EFI_SHELL_PROTOCOL_H__
     18 
     19 #include <Guid/FileInfo.h>
     20 
     21 #define EFI_SHELL_PROTOCOL_GUID \
     22   { \
     23   0x6302d008, 0x7f9b, 0x4f30, { 0x87, 0xac, 0x60, 0xc9, 0xfe, 0xf5, 0xda, 0x4e } \
     24   }
     25 typedef VOID *SHELL_FILE_HANDLE;
     26 
     27 typedef enum {
     28   ///
     29   /// The operation completed successfully.
     30   ///
     31   SHELL_SUCCESS               = 0,
     32 
     33   ///
     34   /// The image failed to load.
     35   ///
     36   SHELL_LOAD_ERROR            = 1,
     37 
     38   ///
     39   /// The parameter was incorrect.
     40   ///
     41   SHELL_INVALID_PARAMETER     = 2,
     42 
     43   ///
     44   /// The operation is not supported.
     45   ///
     46   SHELL_UNSUPPORTED           = 3,
     47 
     48   ///
     49   /// The buffer was not the proper size for the request.
     50   ///
     51   SHELL_BAD_BUFFER_SIZE       = 4,
     52 
     53   ///
     54   /// The buffer was not large enough to hold the requested data.
     55   /// The required buffer size is returned in the appropriate
     56   /// parameter when this error occurs.
     57   ///
     58   SHELL_BUFFER_TOO_SMALL      = 5,
     59 
     60   ///
     61   /// There is no data pending upon return.
     62   ///
     63   SHELL_NOT_READY             = 6,
     64 
     65   ///
     66   /// The physical device reported an error while attempting the
     67   /// operation.
     68   ///
     69   SHELL_DEVICE_ERROR          = 7,
     70 
     71   ///
     72   /// The device cannot be written to.
     73   ///
     74   SHELL_WRITE_PROTECTED       = 8,
     75 
     76   ///
     77   /// The resource has run out.
     78   ///
     79   SHELL_OUT_OF_RESOURCES      = 9,
     80 
     81   ///
     82   /// An inconsistency was detected on the file system causing the
     83   /// operation to fail.
     84   ///
     85   SHELL_VOLUME_CORRUPTED      = 10,
     86 
     87   ///
     88   /// There is no more space on the file system.
     89   ///
     90   SHELL_VOLUME_FULL           = 11,
     91 
     92   ///
     93   /// The device does not contain any medium to perform the
     94   /// operation.
     95   ///
     96   SHELL_NO_MEDIA              = 12,
     97 
     98   ///
     99   /// The medium in the device has changed since the last
    100   /// access.
    101   ///
    102   SHELL_MEDIA_CHANGED         = 13,
    103 
    104   ///
    105   /// The item was not found.
    106   ///
    107   SHELL_NOT_FOUND             = 14,
    108 
    109   ///
    110   /// Access was denied.
    111   ///
    112   SHELL_ACCESS_DENIED         = 15,
    113 
    114   // note the skipping of 16 and 17
    115 
    116   ///
    117   /// A timeout time expired.
    118   ///
    119   SHELL_TIMEOUT               = 18,
    120 
    121   ///
    122   /// The protocol has not been started.
    123   ///
    124   SHELL_NOT_STARTED           = 19,
    125 
    126   ///
    127   /// The protocol has already been started.
    128   ///
    129   SHELL_ALREADY_STARTED       = 20,
    130 
    131   ///
    132   /// The operation was aborted.
    133   ///
    134   SHELL_ABORTED               = 21,
    135 
    136   // note the skipping of 22, 23, and 24
    137 
    138   ///
    139   /// A function encountered an internal version that was
    140   /// incompatible with a version requested by the caller.
    141   ///
    142   SHELL_INCOMPATIBLE_VERSION  = 25,
    143 
    144   ///
    145   /// The function was not performed due to a security violation.
    146   ///
    147   SHELL_SECURITY_VIOLATION    = 26,
    148 
    149   ///
    150   /// The function was performed and resulted in an unequal
    151   /// comparison..
    152   ///
    153   SHELL_NOT_EQUAL             = 27
    154 } SHELL_STATUS;
    155 
    156 
    157 // replaced EFI_LIST_ENTRY with LIST_ENTRY for simplicity.
    158 // they are identical outside of the name.
    159 typedef struct {
    160   LIST_ENTRY        Link;       ///< Linked list members.
    161   EFI_STATUS        Status;     ///< Status of opening the file.  Valid only if Handle != NULL.
    162   CONST CHAR16      *FullName;  ///< Fully qualified filename.
    163   CONST CHAR16      *FileName;  ///< name of this file.
    164   SHELL_FILE_HANDLE Handle;     ///< Handle for interacting with the opened file or NULL if closed.
    165   EFI_FILE_INFO     *Info;      ///< Pointer to the FileInfo struct for this file or NULL.
    166 } EFI_SHELL_FILE_INFO;
    167 
    168 /**
    169   Returns whether any script files are currently being processed.
    170 
    171   @retval TRUE                 There is at least one script file active.
    172   @retval FALSE                No script files are active now.
    173 
    174 **/
    175 typedef
    176 BOOLEAN
    177 (EFIAPI *EFI_SHELL_BATCH_IS_ACTIVE) (
    178   VOID
    179   );
    180 
    181 /**
    182   Closes the file handle.
    183 
    184   This function closes a specified file handle. All 'dirty' cached file data is
    185   flushed to the device, and the file is closed. In all cases, the handle is
    186   closed.
    187 
    188   @param[in] FileHandle         The file handle to be closed.
    189 
    190   @retval EFI_SUCCESS           The file closed sucessfully.
    191 **/
    192 typedef
    193 EFI_STATUS
    194 (EFIAPI *EFI_SHELL_CLOSE_FILE)(
    195   IN SHELL_FILE_HANDLE FileHandle
    196   );
    197 
    198 /**
    199   Creates a file or directory by name.
    200 
    201   This function creates an empty new file or directory with the specified attributes and
    202   returns the new file's handle. If the file already exists and is read-only, then
    203   EFI_INVALID_PARAMETER will be returned.
    204 
    205   If the file already existed, it is truncated and its attributes updated. If the file is
    206   created successfully, the FileHandle is the file's handle, else, the FileHandle is NULL.
    207 
    208   If the file name begins with >v, then the file handle which is returned refers to the
    209   shell environment variable with the specified name. If the shell environment variable
    210   already exists and is non-volatile then EFI_INVALID_PARAMETER is returned.
    211 
    212   @param[in] FileName           Pointer to NULL-terminated file path.
    213   @param[in] FileAttribs        The new file's attrbiutes.  The different attributes are
    214                                 described in EFI_FILE_PROTOCOL.Open().
    215   @param[out] FileHandle        On return, points to the created file handle or directory's handle.
    216 
    217   @retval EFI_SUCCESS           The file was opened.  FileHandle points to the new file's handle.
    218   @retval EFI_INVALID_PARAMETER One of the parameters has an invalid value.
    219   @retval EFI_UNSUPPORTED       The file path could not be opened.
    220   @retval EFI_NOT_FOUND         The specified file could not be found on the device, or could not
    221                                 file the file system on the device.
    222   @retval EFI_NO_MEDIA          The device has no medium.
    223   @retval EFI_MEDIA_CHANGED     The device has a different medium in it or the medium is no
    224                                 longer supported.
    225   @retval EFI_DEVICE_ERROR      The device reported an error or can't get the file path according
    226                                 the DirName.
    227   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
    228   @retval EFI_WRITE_PROTECTED   An attempt was made to create a file, or open a file for write
    229                                 when the media is write-protected.
    230   @retval EFI_ACCESS_DENIED     The service denied access to the file.
    231   @retval EFI_OUT_OF_RESOURCES  Not enough resources were available to open the file.
    232   @retval EFI_VOLUME_FULL       The volume is full.
    233 **/
    234 typedef
    235 EFI_STATUS
    236 (EFIAPI *EFI_SHELL_CREATE_FILE)(
    237   IN CONST CHAR16               *FileName,
    238   IN UINT64                     FileAttribs,
    239   OUT SHELL_FILE_HANDLE         *FileHandle
    240   );
    241 
    242 /**
    243   Deletes the file specified by the file handle.
    244 
    245   This function closes and deletes a file. In all cases, the file handle is closed. If the file
    246   cannot be deleted, the warning code EFI_WARN_DELETE_FAILURE is returned, but the
    247   handle is still closed.
    248 
    249   @param[in] FileHandle           The file handle to delete.
    250 
    251   @retval EFI_SUCCESS             The file was closed and deleted and the handle was closed.
    252   @retval EFI_WARN_DELETE_FAILURE The handle was closed but the file was not deleted.
    253 **/
    254 typedef
    255 EFI_STATUS
    256 (EFIAPI *EFI_SHELL_DELETE_FILE)(
    257   IN SHELL_FILE_HANDLE FileHandle
    258   );
    259 
    260 /**
    261   Deletes the file specified by the file name.
    262 
    263   This function deletes a file.
    264 
    265   @param[in] FileName             Points to the NULL-terminated file name.
    266 
    267   @retval EFI_SUCCESS             The file was deleted.
    268   @retval EFI_WARN_DELETE_FAILURE The handle was closed but the file was not deleted.
    269 **/
    270 typedef
    271 EFI_STATUS
    272 (EFIAPI *EFI_SHELL_DELETE_FILE_BY_NAME)(
    273   IN CONST CHAR16 *FileName
    274   );
    275 
    276 /**
    277   Disables the page break output mode.
    278 **/
    279 typedef
    280 VOID
    281 (EFIAPI *EFI_SHELL_DISABLE_PAGE_BREAK) (
    282   VOID
    283   );
    284 
    285 /**
    286   Enables the page break output mode.
    287 **/
    288 typedef
    289 VOID
    290 (EFIAPI *EFI_SHELL_ENABLE_PAGE_BREAK) (
    291   VOID
    292   );
    293 
    294 /**
    295   Execute the command line.
    296 
    297   This function creates a nested instance of the shell and executes the specified
    298   command (CommandLine) with the specified environment (Environment). Upon return,
    299   the status code returned by the specified command is placed in StatusCode.
    300 
    301   If Environment is NULL, then the current environment is used and all changes made
    302   by the commands executed will be reflected in the current environment. If the
    303   Environment is non-NULL, then the changes made will be discarded.
    304 
    305   The CommandLine is executed from the current working directory on the current
    306   device.
    307 
    308   @param[in] ParentImageHandle  A handle of the image that is executing the specified
    309                                 command line.
    310   @param[in] CommandLine        Points to the NULL-terminated UCS-2 encoded string
    311                                 containing the command line. If NULL then the command-
    312                                 line will be empty.
    313   @param[in] Environment        Points to a NULL-terminated array of environment
    314                                 variables with the format 'x=y', where x is the
    315                                 environment variable name and y is the value. If this
    316                                 is NULL, then the current shell environment is used.
    317   @param[out] ErrorCode         Points to the status code returned by the command.
    318 
    319   @retval EFI_SUCCESS           The command executed successfully. The  status code
    320                                 returned by the command is pointed to by StatusCode.
    321   @retval EFI_INVALID_PARAMETER The parameters are invalid.
    322   @retval EFI_OUT_OF_RESOURCES  Out of resources.
    323   @retval EFI_UNSUPPORTED       Nested shell invocations are not allowed.
    324 **/
    325 typedef
    326 EFI_STATUS
    327 (EFIAPI *EFI_SHELL_EXECUTE) (
    328   IN EFI_HANDLE                 *ParentImageHandle,
    329   IN CHAR16                     *CommandLine OPTIONAL,
    330   IN CHAR16                     **Environment OPTIONAL,
    331   OUT EFI_STATUS                *StatusCode OPTIONAL
    332   );
    333 
    334 /**
    335   Find files that match a specified pattern.
    336 
    337   This function searches for all files and directories that match the specified
    338   FilePattern. The FilePattern can contain wild-card characters. The resulting file
    339   information is placed in the file list FileList.
    340 
    341   The files in the file list are not opened. The OpenMode field is set to 0 and the FileInfo
    342   field is set to NULL.
    343 
    344   @param[in] FilePattern        Points to a NULL-terminated shell file path, including wildcards.
    345   @param[out] FileList          On return, points to the start of a file list containing the names
    346                                 of all matching files or else points to NULL if no matching files
    347                                 were found.
    348 
    349   @retval EFI_SUCCESS           Files found.
    350   @retval EFI_NOT_FOUND         No files found.
    351   @retval EFI_NO_MEDIA          The device has no media.
    352   @retval EFI_DEVICE_ERROR      The device reported an error.
    353   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
    354 **/
    355 typedef
    356 EFI_STATUS
    357 (EFIAPI *EFI_SHELL_FIND_FILES)(
    358   IN CONST CHAR16               *FilePattern,
    359   OUT EFI_SHELL_FILE_INFO       **FileList
    360   );
    361 
    362 /**
    363   Find all files in a specified directory.
    364 
    365   @param[in] FileDirHandle      Handle of the directory to search.
    366   @param[out] FileList          On return, points to the list of files in the directory
    367                                 or NULL if there are no files in the directory.
    368 
    369   @retval EFI_SUCCESS           File information was returned successfully.
    370   @retval EFI_VOLUME_CORRUPTED  The file system structures have been corrupted.
    371   @retval EFI_DEVICE_ERROR      The device reported an error.
    372   @retval EFI_NO_MEDIA          The device media is not present.
    373 **/
    374 typedef
    375 EFI_STATUS
    376 (EFIAPI *EFI_SHELL_FIND_FILES_IN_DIR)(
    377 IN SHELL_FILE_HANDLE            FileDirHandle,
    378 OUT EFI_SHELL_FILE_INFO         **FileList
    379 );
    380 
    381 /**
    382   Flushes data back to a device.
    383 
    384   This function flushes all modified data associated with a file to a device.
    385 
    386   @param[in] FileHandle         The handle of the file to flush.
    387 
    388   @retval EFI_SUCCESS           The data was flushed.
    389   @retval EFI_NO_MEDIA          The device has no medium.
    390   @retval EFI_DEVICE_ERROR      The device reported an error.
    391   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
    392   @retval EFI_WRITE_PROTECTED   The file or medium is write-protected.
    393   @retval EFI_ACCESS_DENIED     The file was opened read-only.
    394   @retval EFI_VOLUME_FULL       The volume is full.
    395 **/
    396 typedef
    397 EFI_STATUS
    398 (EFIAPI *EFI_SHELL_FLUSH_FILE)(
    399   IN SHELL_FILE_HANDLE FileHandle
    400   );
    401 
    402 /**
    403   Frees the file list.
    404 
    405   This function cleans up the file list and any related data structures. It has no
    406   impact on the files themselves.
    407 
    408   @param[in] FileList           The file list to free. Type EFI_SHELL_FILE_INFO is
    409                                 defined in OpenFileList().
    410 
    411   @retval EFI_SUCCESS           Free the file list successfully.
    412 **/
    413 typedef
    414 EFI_STATUS
    415 (EFIAPI *EFI_SHELL_FREE_FILE_LIST) (
    416   IN EFI_SHELL_FILE_INFO **FileList
    417   );
    418 
    419 /**
    420   Returns the current directory on the specified device.
    421 
    422   If FileSystemMapping is NULL, it returns the current working directory. If the
    423   FileSystemMapping is not NULL, it returns the current directory associated with the
    424   FileSystemMapping. In both cases, the returned name includes the file system
    425   mapping (i.e. fs0:\current-dir).
    426 
    427   Note that the current directory string should exclude the tailing backslash character.
    428 
    429   @param[in] FileSystemMapping  A pointer to the file system mapping. If NULL,
    430                                 then the current working directory is returned.
    431 
    432   @retval !=NULL                The current directory.
    433   @retval NULL                  Current directory does not exist.
    434 **/
    435 typedef
    436 CONST CHAR16 *
    437 (EFIAPI *EFI_SHELL_GET_CUR_DIR) (
    438   IN CONST CHAR16 *FileSystemMapping OPTIONAL
    439   );
    440 
    441 typedef UINT32 EFI_SHELL_DEVICE_NAME_FLAGS;
    442 #define EFI_DEVICE_NAME_USE_COMPONENT_NAME  0x00000001
    443 #define EFI_DEVICE_NAME_USE_DEVICE_PATH     0x00000002
    444 
    445 /**
    446   Gets the name of the device specified by the device handle.
    447 
    448   This function gets the user-readable name of the device specified by the device
    449   handle. If no user-readable name could be generated, then *BestDeviceName will be
    450   NULL and EFI_NOT_FOUND will be returned.
    451 
    452   If EFI_DEVICE_NAME_USE_COMPONENT_NAME is set, then the function will return the
    453   device's name using the EFI_COMPONENT_NAME2_PROTOCOL, if present on
    454   DeviceHandle.
    455 
    456   If EFI_DEVICE_NAME_USE_DEVICE_PATH is set, then the function will return the
    457   device's name using the EFI_DEVICE_PATH_PROTOCOL, if present on DeviceHandle.
    458   If both EFI_DEVICE_NAME_USE_COMPONENT_NAME and
    459   EFI_DEVICE_NAME_USE_DEVICE_PATH are set, then
    460   EFI_DEVICE_NAME_USE_COMPONENT_NAME will have higher priority.
    461 
    462   @param[in] DeviceHandle       The handle of the device.
    463   @param[in] Flags              Determines the possible sources of component names.
    464   @param[in] Language           A pointer to the language specified for the device
    465                                 name, in the same format as described in the UEFI
    466                                 specification, Appendix M.
    467   @param[out] BestDeviceName    On return, points to the callee-allocated NULL-
    468                                 terminated name of the device. If no device name
    469                                 could be found, points to NULL. The name must be
    470                                 freed by the caller...
    471 
    472   @retval EFI_SUCCESS           Get the name successfully.
    473   @retval EFI_NOT_FOUND         Fail to get the device name.
    474 **/
    475 typedef
    476 EFI_STATUS
    477 (EFIAPI *EFI_SHELL_GET_DEVICE_NAME) (
    478   IN EFI_HANDLE                   DeviceHandle,
    479   IN EFI_SHELL_DEVICE_NAME_FLAGS  Flags,
    480   IN CHAR8                        *Language,
    481   OUT CHAR16                      **BestDeviceName
    482   );
    483 
    484 /**
    485   Gets the device path from the mapping.
    486 
    487   This function gets the device path associated with a mapping.
    488 
    489   @param[in] Mapping                A pointer to the mapping
    490 
    491   @retval !=NULL                Pointer to the device path that corresponds to the
    492                                 device mapping. The returned pointer does not need
    493                                 to be freed.
    494   @retval NULL                  There is no device path associated with the
    495                                 specified mapping.
    496 **/
    497 typedef
    498 CONST EFI_DEVICE_PATH_PROTOCOL *
    499 (EFIAPI *EFI_SHELL_GET_DEVICE_PATH_FROM_MAP) (
    500   IN CONST CHAR16 *Mapping
    501   );
    502 
    503 /**
    504   Converts a file system style name to a device path.
    505 
    506   This function converts a file system style name to a device path, by replacing any
    507   mapping references to the associated device path.
    508 
    509   @param[in] Path               The pointer to the path.
    510 
    511   @return                       The pointer of the file path. The file path is callee
    512                                 allocated and should be freed by the caller.
    513 **/
    514 typedef
    515 EFI_DEVICE_PATH_PROTOCOL *
    516 (EFIAPI *EFI_SHELL_GET_DEVICE_PATH_FROM_FILE_PATH) (
    517   IN CONST CHAR16 *Path
    518   );
    519 
    520 /**
    521   Gets either a single or list of environment variables.
    522 
    523   If name is not NULL then this function returns the current value of the specified
    524   environment variable.
    525 
    526   If Name is NULL than a list of all environment variable names is returned.  Each a
    527   NULL terminated string with a double NULL terminating the list.
    528 
    529   @param[in] Name               A pointer to the environment variable name.  If
    530                                 Name is NULL, then the function will return all
    531                                 of the defined shell environment variables.  In
    532                                 the case where multiple environment variables are
    533                                 being returned, each variable will be terminated by
    534                                 a NULL, and the list will be terminated by a double
    535                                 NULL.
    536 
    537   @return                       A pointer to the returned string.
    538                                 The returned pointer does not need to be freed by the caller.
    539 
    540   @retval NULL                  The environment variable doesn't exist or there are
    541                                 no environment variables.
    542 **/
    543 typedef
    544 CONST CHAR16 *
    545 (EFIAPI *EFI_SHELL_GET_ENV) (
    546   IN CONST CHAR16 *Name OPTIONAL
    547   );
    548 
    549 /**
    550   Gets the environment variable and Attributes, or list of environment variables.  Can be
    551   used instead of GetEnv().
    552 
    553   This function returns the current value of the specified environment variable and
    554   the Attributes. If no variable name was specified, then all of the known
    555   variables will be returned.
    556 
    557   @param[in] Name               A pointer to the environment variable name. If Name is NULL,
    558                                 then the function will return all of the defined shell
    559                                 environment variables. In the case where multiple environment
    560                                 variables are being returned, each variable will be terminated
    561                                 by a NULL, and the list will be terminated by a double NULL.
    562   @param[out] Attributes        If not NULL, a pointer to the returned attributes bitmask for
    563                                 the environment variable. In the case where Name is NULL, and
    564                                 multiple environment variables are being returned, Attributes
    565                                 is undefined.
    566 
    567   @retval NULL                  The environment variable doesn't exist.
    568   @return                       The environment variable's value. The returned pointer does not
    569                                 need to be freed by the caller.
    570 **/
    571 typedef
    572 CONST CHAR16 *
    573 (EFIAPI *EFI_SHELL_GET_ENV_EX) (
    574   IN  CONST CHAR16 *Name,
    575   OUT       UINT32 *Attributes OPTIONAL
    576   );
    577 
    578 /**
    579   Gets the file information from an open file handle.
    580 
    581   This function allocates a buffer to store the file's information. It's the caller's
    582   responsibility to free the buffer.
    583 
    584   @param[in] FileHandle         A File Handle.
    585 
    586   @retval NULL                  Cannot get the file info.
    587   @return                       A pointer to a buffer with file information.
    588 **/
    589 typedef
    590 EFI_FILE_INFO *
    591 (EFIAPI *EFI_SHELL_GET_FILE_INFO)(
    592   IN SHELL_FILE_HANDLE FileHandle
    593   );
    594 
    595 /**
    596   Converts a device path to a file system-style path.
    597 
    598   This function converts a device path to a file system path by replacing part, or all, of
    599   the device path with the file-system mapping. If there are more than one application
    600   file system mappings, the one that most closely matches Path will be used.
    601 
    602   @param[in] Path               The pointer to the device path.
    603 
    604   @return                       The pointer of the NULL-terminated file path. The path
    605                                 is callee-allocated and should be freed by the caller.
    606 **/
    607 typedef
    608 CHAR16 *
    609 (EFIAPI *EFI_SHELL_GET_FILE_PATH_FROM_DEVICE_PATH) (
    610   IN CONST EFI_DEVICE_PATH_PROTOCOL *Path
    611   );
    612 
    613 /**
    614   Gets a file's current position.
    615 
    616   This function returns the current file position for the file handle. For directories, the
    617   current file position has no meaning outside of the file system driver and as such, the
    618   operation is not supported.
    619 
    620   @param[in] FileHandle         The file handle on which to get the current position.
    621   @param[out] Position          Byte position from the start of the file.
    622 
    623   @retval EFI_SUCCESS           Data was accessed.
    624   @retval EFI_UNSUPPORTED       The request is not valid on open directories.
    625 **/
    626 typedef
    627 EFI_STATUS
    628 (EFIAPI *EFI_SHELL_GET_FILE_POSITION)(
    629   IN SHELL_FILE_HANDLE FileHandle,
    630   OUT UINT64 *Position
    631   );
    632 
    633 /**
    634   Gets the size of a file.
    635 
    636   This function returns the size of the file specified by FileHandle.
    637 
    638   @param[in] FileHandle         The handle of the file.
    639   @param[out] Size              The size of this file.
    640 
    641   @retval EFI_SUCCESS           Get the file's size.
    642   @retval EFI_DEVICE_ERROR      Can't access the file.
    643 **/
    644 typedef
    645 EFI_STATUS
    646 (EFIAPI *EFI_SHELL_GET_FILE_SIZE)(
    647   IN SHELL_FILE_HANDLE FileHandle,
    648   OUT UINT64 *Size
    649   );
    650 
    651 /**
    652   Get the GUID value from a human readable name.
    653 
    654   If GuidName is a known GUID name, then update Guid to have the correct value for
    655   that GUID.
    656 
    657   This function is only available when the major and minor versions in the
    658   EfiShellProtocol are greater than or equal to 2 and 1, respectively.
    659 
    660   @param[in]  GuidName   A pointer to the localized name for the GUID being queried.
    661   @param[out] Guid       A pointer to the GUID structure to be filled in.
    662 
    663   @retval EFI_SUCCESS             The operation was successful.
    664   @retval EFI_INVALID_PARAMETER   Guid was NULL.
    665   @retval EFI_INVALID_PARAMETER   GuidName was NULL.
    666   @retval EFI_NOT_FOUND           GuidName is not a known GUID Name.
    667 **/
    668 typedef
    669 EFI_STATUS
    670 (EFIAPI *EFI_SHELL_GET_GUID_FROM_NAME)(
    671   IN  CONST CHAR16   *GuidName,
    672   OUT       EFI_GUID *Guid
    673   );
    674 
    675 /**
    676   Get the human readable name for a GUID from the value.
    677 
    678   If Guid is assigned a name, then update *GuidName to point to the name. The callee
    679   should not modify the value.
    680 
    681   This function is only available when the major and minor versions in the
    682   EfiShellProtocol are greater than or equal to 2 and 1, respectively.
    683 
    684   @param[in]  Guid       A pointer to the GUID being queried.
    685   @param[out] GuidName   A pointer to a pointer the localized to name for the GUID being requested
    686 
    687   @retval EFI_SUCCESS             The operation was successful.
    688   @retval EFI_INVALID_PARAMETER   Guid was NULL.
    689   @retval EFI_INVALID_PARAMETER   GuidName was NULL.
    690   @retval EFI_NOT_FOUND           Guid is not assigned a name.
    691 **/
    692 typedef
    693 EFI_STATUS
    694 (EFIAPI *EFI_SHELL_GET_GUID_NAME)(
    695   IN  CONST EFI_GUID *Guid,
    696   OUT CONST CHAR16   **GuidName
    697   );
    698 
    699 /**
    700   Return help information about a specific command.
    701 
    702   This function returns the help information for the specified command. The help text
    703   can be internal to the shell or can be from a UEFI Shell manual page.
    704 
    705   If Sections is specified, then each section name listed will be compared in a casesensitive
    706   manner, to the section names described in Appendix B. If the section exists,
    707   it will be appended to the returned help text. If the section does not exist, no
    708   information will be returned. If Sections is NULL, then all help text information
    709   available will be returned.
    710 
    711   @param[in] Command            Points to the NULL-terminated UEFI Shell command name.
    712   @param[in] Sections           Points to the NULL-terminated comma-delimited
    713                                 section names to return. If NULL, then all
    714                                 sections will be returned.
    715   @param[out] HelpText          On return, points to a callee-allocated buffer
    716                                 containing all specified help text.
    717 
    718   @retval EFI_SUCCESS           The help text was returned.
    719   @retval EFI_OUT_OF_RESOURCES  The necessary buffer could not be allocated to hold the
    720                                 returned help text.
    721   @retval EFI_INVALID_PARAMETER HelpText is NULL.
    722   @retval EFI_NOT_FOUND         There is no help text available for Command.
    723 **/
    724 typedef
    725 EFI_STATUS
    726 (EFIAPI *EFI_SHELL_GET_HELP_TEXT) (
    727   IN CONST CHAR16 *Command,
    728   IN CONST CHAR16 *Sections OPTIONAL,
    729   OUT CHAR16 **HelpText
    730   );
    731 
    732 /**
    733   Gets the mapping(s) that most closely matches the device path.
    734 
    735   This function gets the mapping which corresponds to the device path *DevicePath. If
    736   there is no exact match, then the mapping which most closely matches *DevicePath
    737   is returned, and *DevicePath is updated to point to the remaining portion of the
    738   device path. If there is an exact match, the mapping is returned and *DevicePath
    739   points to the end-of-device-path node.
    740 
    741   If there are multiple map names they will be semi-colon seperated in the
    742   NULL-terminated string.
    743 
    744   @param[in, out] DevicePath     On entry, points to a device path pointer. On
    745                                  exit, updates the pointer to point to the
    746                                  portion of the device path after the mapping.
    747 
    748   @retval NULL                  No mapping was found.
    749   @retval !=NULL                Pointer to NULL-terminated mapping. The buffer
    750                                 is callee allocated and should be freed by the caller.
    751 **/
    752 typedef
    753 CONST CHAR16 *
    754 (EFIAPI *EFI_SHELL_GET_MAP_FROM_DEVICE_PATH) (
    755   IN OUT EFI_DEVICE_PATH_PROTOCOL **DevicePath
    756   );
    757 
    758 /**
    759   Gets the enable status of the page break output mode.
    760 
    761   User can use this function to determine current page break mode.
    762 
    763   @retval TRUE                  The page break output mode is enabled.
    764   @retval FALSE                 The page break output mode is disabled.
    765 **/
    766 typedef
    767 BOOLEAN
    768 (EFIAPI *EFI_SHELL_GET_PAGE_BREAK) (
    769   VOID
    770   );
    771 
    772 /**
    773   Judges whether the active shell is the root shell.
    774 
    775   This function makes the user to know that whether the active Shell is the root shell.
    776 
    777   @retval TRUE                  The active Shell is the root Shell.
    778   @retval FALSE                 The active Shell is NOT the root Shell.
    779 **/
    780 typedef
    781 BOOLEAN
    782 (EFIAPI *EFI_SHELL_IS_ROOT_SHELL) (
    783 VOID
    784 );
    785 
    786 /**
    787   Opens a file or a directory by file name.
    788 
    789   This function opens the specified file in the specified OpenMode and returns a file
    790   handle.
    791   If the file name begins with '>v', then the file handle which is returned refers to the
    792   shell environment variable with the specified name. If the shell environment variable
    793   exists, is non-volatile and the OpenMode indicates EFI_FILE_MODE_WRITE, then
    794   EFI_INVALID_PARAMETER is returned.
    795 
    796   If the file name is '>i', then the file handle which is returned refers to the standard
    797   input. If the OpenMode indicates EFI_FILE_MODE_WRITE, then EFI_INVALID_PARAMETER
    798   is returned.
    799 
    800   If the file name is '>o', then the file handle which is returned refers to the standard
    801   output. If the OpenMode indicates EFI_FILE_MODE_READ, then EFI_INVALID_PARAMETER
    802   is returned.
    803 
    804   If the file name is '>e', then the file handle which is returned refers to the standard
    805   error. If the OpenMode indicates EFI_FILE_MODE_READ, then EFI_INVALID_PARAMETER
    806   is returned.
    807 
    808   If the file name is 'NUL', then the file handle that is returned refers to the standard NUL
    809   file. If the OpenMode indicates EFI_FILE_MODE_READ, then EFI_INVALID_PARAMETER is
    810   returned.
    811 
    812   If return EFI_SUCCESS, the FileHandle is the opened file's handle, else, the
    813   FileHandle is NULL.
    814 
    815   @param[in] FileName           Points to the NULL-terminated UCS-2 encoded file name.
    816   @param[out] FileHandle        On return, points to the file handle.
    817   @param[in] OpenMode           File open mode. Either EFI_FILE_MODE_READ or
    818                                 EFI_FILE_MODE_WRITE from section 12.4 of the UEFI
    819                                 Specification.
    820   @retval EFI_SUCCESS           The file was opened. FileHandle has the opened file's handle.
    821   @retval EFI_INVALID_PARAMETER One of the parameters has an invalid value. FileHandle is NULL.
    822   @retval EFI_UNSUPPORTED       Could not open the file path. FileHandle is NULL.
    823   @retval EFI_NOT_FOUND         The specified file could not be found on the device or the file
    824                                 system could not be found on the device. FileHandle is NULL.
    825   @retval EFI_NO_MEDIA          The device has no medium. FileHandle is NULL.
    826   @retval EFI_MEDIA_CHANGED     The device has a different medium in it or the medium is no
    827                                 longer supported. FileHandle is NULL.
    828   @retval EFI_DEVICE_ERROR      The device reported an error or can't get the file path according
    829                                 the FileName. FileHandle is NULL.
    830   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted. FileHandle is NULL.
    831   @retval EFI_WRITE_PROTECTED   An attempt was made to create a file, or open a file for write
    832                                 when the media is write-protected. FileHandle is NULL.
    833   @retval EFI_ACCESS_DENIED     The service denied access to the file. FileHandle is NULL.
    834   @retval EFI_OUT_OF_RESOURCES  Not enough resources were available to open the file. FileHandle
    835                                 is NULL.
    836   @retval EFI_VOLUME_FULL       The volume is full. FileHandle is NULL.
    837 **/
    838 typedef
    839 EFI_STATUS
    840 (EFIAPI *EFI_SHELL_OPEN_FILE_BY_NAME) (
    841   IN CONST CHAR16 *FileName,
    842   OUT SHELL_FILE_HANDLE *FileHandle,
    843   IN UINT64 OpenMode
    844   );
    845 
    846 /**
    847   Opens the files that match the path specified.
    848 
    849   This function opens all of the files specified by Path. Wildcards are processed
    850   according to the rules specified in UEFI Shell 2.0 spec section 3.7.1. Each
    851   matching file has an EFI_SHELL_FILE_INFO structure created in a linked list.
    852 
    853   @param[in] Path                A pointer to the path string.
    854   @param[in] OpenMode            Specifies the mode used to open each file, EFI_FILE_MODE_READ or
    855                                  EFI_FILE_MODE_WRITE.
    856   @param[in, out] FileList       Points to the start of a list of files opened.
    857 
    858   @retval EFI_SUCCESS           Create the file list successfully.
    859   @return                       Can't create the file list.
    860 **/
    861 typedef
    862 EFI_STATUS
    863 (EFIAPI *EFI_SHELL_OPEN_FILE_LIST) (
    864   IN CHAR16 *Path,
    865   IN UINT64 OpenMode,
    866   IN OUT EFI_SHELL_FILE_INFO **FileList
    867   );
    868 
    869 /**
    870   Opens the root directory of a device.
    871 
    872   This function opens the root directory of a device and returns a file handle to it.
    873 
    874   @param[in] DevicePath         Points to the device path corresponding to the device where the
    875                                 EFI_SIMPLE_FILE_SYSTEM_PROTOCOL is installed.
    876   @param[out] FileHandle        On exit, points to the file handle corresponding to the root directory on the
    877                                 device.
    878 
    879   @retval EFI_SUCCESS           Root opened successfully.
    880   @retval EFI_NOT_FOUND         EFI_SIMPLE_FILE_SYSTEM could not be found or the root directory
    881                                 could not be opened.
    882   @retval EFI_VOLUME_CORRUPTED  The data structures in the volume were corrupted.
    883   @retval EFI_DEVICE_ERROR      The device had an error.
    884 **/
    885 typedef
    886 EFI_STATUS
    887 (EFIAPI *EFI_SHELL_OPEN_ROOT)(
    888   IN EFI_DEVICE_PATH_PROTOCOL *DevicePath,
    889   OUT SHELL_FILE_HANDLE *FileHandle
    890   );
    891 
    892 /**
    893   Opens the root directory of a device on a handle.
    894 
    895   This function opens the root directory of a device and returns a file handle to it.
    896 
    897   @param[in] DeviceHandle       The handle of the device that contains the volume.
    898   @param[out] FileHandle        On exit, points to the file handle corresponding to the root directory on the
    899                                 device.
    900 
    901   @retval EFI_SUCCESS           Root opened successfully.
    902   @retval EFI_NOT_FOUND         EFI_SIMPLE_FILE_SYSTEM could not be found or the root directory
    903                                 could not be opened.
    904   @retval EFI_VOLUME_CORRUPTED  The data structures in the volume were corrupted.
    905   @retval EFI_DEVICE_ERROR      The device had an error.
    906 **/
    907 typedef
    908 EFI_STATUS
    909 (EFIAPI *EFI_SHELL_OPEN_ROOT_BY_HANDLE)(
    910   IN EFI_HANDLE DeviceHandle,
    911   OUT SHELL_FILE_HANDLE *FileHandle
    912   );
    913 
    914 /**
    915   Reads data from the file.
    916 
    917   If FileHandle is not a directory, the function reads the requested number of bytes
    918   from the file at the file's current position and returns them in Buffer. If the read goes
    919   beyond the end of the file, the read length is truncated to the end of the file. The file's
    920   current position is increased by the number of bytes returned.
    921   If FileHandle is a directory, then an error is returned.
    922 
    923   @param[in] FileHandle          The opened file handle for read.
    924   @param[in] ReadSize            On input, the size of Buffer, in bytes. On output, the amount of data read.
    925   @param[in, out] Buffer         The buffer in which data is read.
    926 
    927   @retval EFI_SUCCESS           Data was read.
    928   @retval EFI_NO_MEDIA          The device has no media.
    929   @retval EFI_DEVICE_ERROR      The device reported an error.
    930   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
    931   @retval EFI_BUFFER_TO_SMALL   Buffer is too small. ReadSize contains required size.
    932 **/
    933 typedef
    934 EFI_STATUS
    935 (EFIAPI *EFI_SHELL_READ_FILE) (
    936   IN SHELL_FILE_HANDLE FileHandle,
    937   IN OUT UINTN *ReadSize,
    938   IN OUT VOID *Buffer
    939   );
    940 
    941 /**
    942   Register a GUID and a localized human readable name for it.
    943 
    944   If Guid is not assigned a name, then assign GuidName to Guid.  This list of GUID
    945   names must be used whenever a shell command outputs GUID information.
    946 
    947   This function is only available when the major and minor versions in the
    948   EfiShellProtocol are greater than or equal to 2 and 1, respectively.
    949 
    950   @param[in] Guid       A pointer to the GUID being registered.
    951   @param[in] GuidName   A pointer to the localized name for the GUID being registered.
    952 
    953   @retval EFI_SUCCESS             The operation was successful.
    954   @retval EFI_INVALID_PARAMETER   Guid was NULL.
    955   @retval EFI_INVALID_PARAMETER   GuidName was NULL.
    956   @retval EFI_ACCESS_DENIED       Guid already is assigned a name.
    957 **/
    958 typedef
    959 EFI_STATUS
    960 (EFIAPI *EFI_SHELL_REGISTER_GUID_NAME)(
    961   IN CONST EFI_GUID *Guid,
    962   IN CONST CHAR16   *GuidName
    963   );
    964 
    965 /**
    966   Deletes the duplicate file names files in the given file list.
    967 
    968   @param[in] FileList           A pointer to the first entry in the file list.
    969 
    970   @retval EFI_SUCCESS           Always success.
    971 **/
    972 typedef
    973 EFI_STATUS
    974 (EFIAPI *EFI_SHELL_REMOVE_DUP_IN_FILE_LIST) (
    975   IN EFI_SHELL_FILE_INFO **FileList
    976   );
    977 
    978 /**
    979   Changes a shell command alias.
    980 
    981   This function creates an alias for a shell command.
    982 
    983   @param[in] Command            Points to the NULL-terminated shell command or existing alias.
    984   @param[in] Alias              Points to the NULL-terminated alias for the shell command. If this is NULL, and
    985                                 Command refers to an alias, that alias will be deleted.
    986   @param[in] Replace            If TRUE and the alias already exists, then the existing alias will be replaced. If
    987                                 FALSE and the alias already exists, then the existing alias is unchanged and
    988                                 EFI_ACCESS_DENIED is returned.
    989   @param[in] Volatile           if TRUE the Alias being set will be stored in a volatile fashion.  if FALSE the
    990                                 Alias being set will be stored in a non-volatile fashion.
    991 
    992   @retval EFI_SUCCESS           Alias created or deleted successfully.
    993   @retval EFI_ACCESS_DENIED     The alias is a built-in alias or already existed and Replace was set to
    994                                 FALSE.
    995 **/
    996 typedef
    997 EFI_STATUS
    998 (EFIAPI *EFI_SHELL_SET_ALIAS)(
    999   IN CONST CHAR16 *Command,
   1000   IN CONST CHAR16 *Alias,
   1001   IN BOOLEAN Replace,
   1002   IN BOOLEAN Volatile
   1003   );
   1004 
   1005 /**
   1006   This function returns the command associated with a alias or a list of all
   1007   alias'.
   1008 
   1009   @param[in] Alias              Points to the NULL-terminated shell alias.
   1010                                 If this parameter is NULL, then all
   1011                                 aliases will be returned in ReturnedData.
   1012   @param[out] Volatile          Upon return of a single command if TRUE indicates
   1013                                 this is stored in a volatile fashion.  FALSE otherwise.
   1014   @return                      	If Alias is not NULL, it will return a pointer to
   1015                                 the NULL-terminated command for that alias.
   1016                                 If Alias is NULL, ReturnedData points to a ';'
   1017                                 delimited list of alias (e.g.
   1018                                 ReturnedData = "dir;del;copy;mfp") that is NULL-terminated.
   1019   @retval NULL                  An error ocurred.
   1020   @retval NULL                  Alias was not a valid Alias.
   1021 **/
   1022 typedef
   1023 CONST CHAR16 *
   1024 (EFIAPI *EFI_SHELL_GET_ALIAS)(
   1025   IN  CONST CHAR16 *Alias,
   1026   OUT BOOLEAN      *Volatile OPTIONAL
   1027   );
   1028 
   1029 /**
   1030   Changes the current directory on the specified device.
   1031 
   1032   If the FileSystem is NULL, and the directory Dir does not contain a file system's
   1033   mapped name, this function changes the current working directory. If FileSystem is
   1034   NULL and the directory Dir contains a mapped name, then the current file system and
   1035   the current directory on that file system are changed.
   1036 
   1037   If FileSystem is not NULL, and Dir is NULL, then this changes the current working file
   1038   system.
   1039 
   1040   If FileSystem is not NULL and Dir is not NULL, then this function changes the current
   1041   directory on the specified file system.
   1042 
   1043   If the current working directory or the current working file system is changed then the
   1044   %cwd% environment variable will be updated.
   1045 
   1046   @param[in] FileSystem         A pointer to the file system's mapped name. If NULL, then the current working
   1047                                 directory is changed.
   1048   @param[in] Dir                Points to the NULL-terminated directory on the device specified by FileSystem.
   1049 
   1050   @retval NULL                  Current directory does not exist.
   1051   @return                       The current directory.
   1052 **/
   1053 typedef
   1054 EFI_STATUS
   1055 (EFIAPI *EFI_SHELL_SET_CUR_DIR) (
   1056   IN CONST CHAR16 *FileSystem OPTIONAL,
   1057   IN CONST CHAR16 *Dir
   1058   );
   1059 
   1060 /**
   1061   Sets the environment variable.
   1062 
   1063   This function changes the current value of the specified environment variable. If the
   1064   environment variable exists and the Value is an empty string, then the environment
   1065   variable is deleted. If the environment variable exists and the Value is not an empty
   1066   string, then the value of the environment variable is changed. If the environment
   1067   variable does not exist and the Value is an empty string, there is no action. If the
   1068   environment variable does not exist and the Value is a non-empty string, then the
   1069   environment variable is created and assigned the specified value.
   1070 
   1071   For a description of volatile and non-volatile environment variables, see UEFI Shell
   1072   2.0 specification section 3.6.1.
   1073 
   1074   @param[in] Name               Points to the NULL-terminated environment variable name.
   1075   @param[in] Value              Points to the NULL-terminated environment variable value. If the value is an
   1076                                 empty string then the environment variable is deleted.
   1077   @param[in] Volatile           Indicates whether the variable is non-volatile (FALSE) or volatile (TRUE).
   1078 
   1079   @retval EFI_SUCCESS           The environment variable was successfully updated.
   1080 **/
   1081 typedef
   1082 EFI_STATUS
   1083 (EFIAPI *EFI_SHELL_SET_ENV) (
   1084   IN CONST CHAR16 *Name,
   1085   IN CONST CHAR16 *Value,
   1086   IN BOOLEAN Volatile
   1087   );
   1088 
   1089 /**
   1090   Sets the file information to an opened file handle.
   1091 
   1092   This function changes file information.  All file information in the EFI_FILE_INFO
   1093   struct will be updated to the passed in data.
   1094 
   1095   @param[in] FileHandle         A file handle.
   1096   @param[in] FileInfo           Points to new file information.
   1097 
   1098   @retval EFI_SUCCESS           The information was set.
   1099   @retval EFI_NO_MEDIA          The device has no medium.
   1100   @retval EFI_DEVICE_ERROR      The device reported an error.
   1101   @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
   1102   @retval EFI_WRITE_PROTECTED   The file or medium is write-protected.
   1103   @retval EFI_ACCESS_DENIED     The file was opened read-only.
   1104   @retval EFI_VOLUME_FULL       The volume is full.
   1105   @retval EFI_BAD_BUFFER_SIZE   BufferSize is smaller than the size of EFI_FILE_INFO.
   1106 **/
   1107 typedef
   1108 EFI_STATUS
   1109 (EFIAPI *EFI_SHELL_SET_FILE_INFO)(
   1110   IN SHELL_FILE_HANDLE FileHandle,
   1111   IN CONST EFI_FILE_INFO *FileInfo
   1112   );
   1113 
   1114 /**
   1115   Sets a file's current position.
   1116 
   1117   This function sets the current file position for the handle to the position supplied. With
   1118   the exception of seeking to position 0xFFFFFFFFFFFFFFFF, only absolute positioning is
   1119   supported, and seeking past the end of the file is allowed (a subsequent write would
   1120   grow the file). Seeking to position 0xFFFFFFFFFFFFFFFF causes the current position
   1121   to be set to the end of the file.
   1122 
   1123   @param[in] FileHandle         The file handle on which requested position will be set.
   1124   @param[in] Position           Byte position from the start of the file.
   1125 
   1126   @retval EFI_SUCCESS           Data was written.
   1127   @retval EFI_UNSUPPORTED       The seek request for nonzero is not valid on open directories.
   1128 **/
   1129 typedef
   1130 EFI_STATUS
   1131 (EFIAPI *EFI_SHELL_SET_FILE_POSITION)(
   1132   IN SHELL_FILE_HANDLE FileHandle,
   1133   IN UINT64 Position
   1134   );
   1135 
   1136 /**
   1137   This function creates a mapping for a device path.
   1138 
   1139   @param[in] DevicePath         Points to the device path. If this is NULL and Mapping points to a valid mapping,
   1140                                 then the mapping will be deleted.
   1141   @param[in] Mapping            Points to the NULL-terminated mapping for the device path.
   1142 
   1143   @retval EFI_SUCCESS           Mapping created or deleted successfully.
   1144   @retval EFI_NO_MAPPING        There is no handle that corresponds exactly to DevicePath. See the
   1145                                 boot service function LocateDevicePath().
   1146   @retval EFI_ACCESS_DENIED     The mapping is a built-in alias.
   1147 **/
   1148 typedef
   1149 EFI_STATUS
   1150 (EFIAPI *EFI_SHELL_SET_MAP)(
   1151   IN CONST EFI_DEVICE_PATH_PROTOCOL *DevicePath,
   1152   IN CONST CHAR16 *Mapping
   1153   );
   1154 
   1155 /**
   1156   Writes data to the file.
   1157 
   1158   This function writes the specified number of bytes to the file at the current file position.
   1159   The current file position is advanced the actual number of bytes written, which is
   1160   returned in BufferSize. Partial writes only occur when there has been a data error
   1161   during the write attempt (such as "volume space full"). The file automatically grows to
   1162   hold the data, if required.
   1163 
   1164   Direct writes to opened directories are not supported.
   1165 
   1166   @param[in] FileHandle              The opened file handle for writing.
   1167   @param[in, out] BufferSize         On input, size of Buffer.
   1168   @param[in] Buffer                  The buffer in which data to write.
   1169 
   1170   @retval EFI_SUCCESS               Data was written.
   1171   @retval EFI_UNSUPPORTED           Writes to open directory are not supported.
   1172   @retval EFI_NO_MEDIA              The device has no media.
   1173   @retval EFI_DEVICE_ERROR          The device reported an error.
   1174   @retval EFI_VOLUME_CORRUPTED      The file system structures are corrupted.
   1175   @retval EFI_WRITE_PROTECTED       The device is write-protected.
   1176   @retval EFI_ACCESS_DENIED         The file was open for read only.
   1177   @retval EFI_VOLUME_FULL           The volume is full.
   1178 **/
   1179 typedef
   1180 EFI_STATUS
   1181 (EFIAPI *EFI_SHELL_WRITE_FILE)(
   1182   IN SHELL_FILE_HANDLE          FileHandle,
   1183   IN OUT UINTN                  *BufferSize,
   1184   IN VOID                       *Buffer
   1185   );
   1186 
   1187 //
   1188 // EFI_SHELL_PROTOCOL has been updated since UEFI Shell Spec 2.0
   1189 // Usage of this protocol will require version checking before attempting
   1190 // to use any new members.  There is no need to check the version for
   1191 // members that existed in UEFI Shell Spec 2.0.
   1192 //
   1193 // Update below for any future UEFI Shell spec changes to this protocol.
   1194 //
   1195 // Check EFI_SHELL_PROTOCOL MajorVersion and MinorVersion:
   1196 // if ((2 == gEfiShellProtocol->MajorVersion) &&
   1197 //     (0 == gEfiShellProtocol->MinorVersion)) {
   1198 //   //
   1199 //   // Cannot call:
   1200 //   // RegisterGuidName - UEFI Shell 2.1
   1201 //   // GetGuidName      - UEFI Shell 2.1
   1202 //   // GetGuidFromName  - UEFI Shell 2.1
   1203 //   // GetEnvEx         - UEFI Shell 2.1
   1204 //   //
   1205 // } else {
   1206 //   //
   1207 //   // Can use all members
   1208 //   //
   1209 // }
   1210 //
   1211 typedef struct _EFI_SHELL_PROTOCOL {
   1212   EFI_SHELL_EXECUTE                         Execute;
   1213   EFI_SHELL_GET_ENV                         GetEnv;
   1214   EFI_SHELL_SET_ENV                         SetEnv;
   1215   EFI_SHELL_GET_ALIAS                       GetAlias;
   1216   EFI_SHELL_SET_ALIAS                       SetAlias;
   1217   EFI_SHELL_GET_HELP_TEXT                   GetHelpText;
   1218   EFI_SHELL_GET_DEVICE_PATH_FROM_MAP        GetDevicePathFromMap;
   1219   EFI_SHELL_GET_MAP_FROM_DEVICE_PATH        GetMapFromDevicePath;
   1220   EFI_SHELL_GET_DEVICE_PATH_FROM_FILE_PATH  GetDevicePathFromFilePath;
   1221   EFI_SHELL_GET_FILE_PATH_FROM_DEVICE_PATH  GetFilePathFromDevicePath;
   1222   EFI_SHELL_SET_MAP                         SetMap;
   1223   EFI_SHELL_GET_CUR_DIR                     GetCurDir;
   1224   EFI_SHELL_SET_CUR_DIR                     SetCurDir;
   1225   EFI_SHELL_OPEN_FILE_LIST                  OpenFileList;
   1226   EFI_SHELL_FREE_FILE_LIST                  FreeFileList;
   1227   EFI_SHELL_REMOVE_DUP_IN_FILE_LIST         RemoveDupInFileList;
   1228   EFI_SHELL_BATCH_IS_ACTIVE                 BatchIsActive;
   1229   EFI_SHELL_IS_ROOT_SHELL                   IsRootShell;
   1230   EFI_SHELL_ENABLE_PAGE_BREAK               EnablePageBreak;
   1231   EFI_SHELL_DISABLE_PAGE_BREAK              DisablePageBreak;
   1232   EFI_SHELL_GET_PAGE_BREAK                  GetPageBreak;
   1233   EFI_SHELL_GET_DEVICE_NAME                 GetDeviceName;
   1234   EFI_SHELL_GET_FILE_INFO                   GetFileInfo;
   1235   EFI_SHELL_SET_FILE_INFO                   SetFileInfo;
   1236   EFI_SHELL_OPEN_FILE_BY_NAME               OpenFileByName;
   1237   EFI_SHELL_CLOSE_FILE                      CloseFile;
   1238   EFI_SHELL_CREATE_FILE                     CreateFile;
   1239   EFI_SHELL_READ_FILE                       ReadFile;
   1240   EFI_SHELL_WRITE_FILE                      WriteFile;
   1241   EFI_SHELL_DELETE_FILE                     DeleteFile;
   1242   EFI_SHELL_DELETE_FILE_BY_NAME             DeleteFileByName;
   1243   EFI_SHELL_GET_FILE_POSITION               GetFilePosition;
   1244   EFI_SHELL_SET_FILE_POSITION               SetFilePosition;
   1245   EFI_SHELL_FLUSH_FILE                      FlushFile;
   1246   EFI_SHELL_FIND_FILES                      FindFiles;
   1247   EFI_SHELL_FIND_FILES_IN_DIR               FindFilesInDir;
   1248   EFI_SHELL_GET_FILE_SIZE                   GetFileSize;
   1249   EFI_SHELL_OPEN_ROOT                       OpenRoot;
   1250   EFI_SHELL_OPEN_ROOT_BY_HANDLE             OpenRootByHandle;
   1251   EFI_EVENT                                 ExecutionBreak;
   1252   UINT32                                    MajorVersion;
   1253   UINT32                                    MinorVersion;
   1254   // Added for Shell 2.1
   1255   EFI_SHELL_REGISTER_GUID_NAME              RegisterGuidName;
   1256   EFI_SHELL_GET_GUID_NAME                   GetGuidName;
   1257   EFI_SHELL_GET_GUID_FROM_NAME              GetGuidFromName;
   1258   EFI_SHELL_GET_ENV_EX                      GetEnvEx;
   1259 } EFI_SHELL_PROTOCOL;
   1260 
   1261 extern EFI_GUID gEfiShellProtocolGuid;
   1262 
   1263 enum ShellVersion {
   1264   SHELL_MAJOR_VERSION = 2,
   1265   SHELL_MINOR_VERSION = 1
   1266 };
   1267 
   1268 #endif
   1269