path: root/ShellPkg/Include/Library/ShellLib.h

/** @file
  Provides interface to shell functionality for shell commands and applications.

  Copyright (c) 2006 - 2010, Intel Corporation<BR>
  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.

**/

#if !defined(__SHELL_LIB__)
#define __SHELL_LIB__

#include <Uefi.h>
#include <Guid/FileInfo.h>
#include <Protocol/SimpleFileSystem.h>
#include <Protocol/LoadedImage.h>
#include <Protocol/EfiShellInterface.h>
#include <Protocol/EfiShellEnvironment2.h>
#include <Protocol/EfiShell.h>
#include <Protocol/EfiShellParameters.h>

/**
  This function will retrieve the information about the file for the handle 
  specified and store it in allocated pool memory.

  This function allocates a buffer to store the file's information. It is the 
  caller's responsibility to free the buffer.

  @param[in] FileHandle         The file handle of the file for which information is 
                                being requested.

  @retval NULL                  Information could not be retrieved.

  @return                       The information about the file.
**/
EFI_FILE_INFO*
EFIAPI
ShellGetFileInfo (
  IN EFI_FILE_HANDLE            FileHandle
  );

/**
  This function will set the information about the file for the opened handle 
  specified.

  @param[in]  FileHandle        The file handle of the file for which information 
                                is being set.

  @param[in] FileInfo           The infotmation to set.

  @retval EFI_SUCCESS	          The information was set.
  @retval EFI_UNSUPPORTED       The InformationType is not known.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED   The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellSetFileInfo (
  IN EFI_FILE_HANDLE  	        FileHandle,
  IN EFI_FILE_INFO              *FileInfo
  );

/**
  This function will open a file or directory referenced by DevicePath.

  This function opens a file with the open mode according to the file path. The 
  Attributes is valid only for EFI_FILE_MODE_CREATE.

  @param[in]  FilePath 		      On input the device path to the file.  On output 
                                the remaining device path.
  @param[out]  DeviceHandle  	  Pointer to the system device handle.
  @param[out]  FileHandle		    Pointer to the file handle.
  @param[in]  OpenMode	    	  The mode to open the file with.
  @param[in]  Attributes	  	  The file's file attributes.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found on 
                                the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellOpenFileByDevicePath(
  IN OUT EFI_DEVICE_PATH_PROTOCOL  	  **FilePath,
  OUT EFI_HANDLE                    	*DeviceHandle,
  OUT EFI_FILE_HANDLE               	*FileHandle,
  IN UINT64                          	OpenMode,
  IN UINT64                          	Attributes
  );

/**
  This function will open a file or directory referenced by filename.

  If return is EFI_SUCCESS, the Filehandle is the opened file's handle; 
  otherwise, the Filehandle is NULL. The Attributes is valid only for 
  EFI_FILE_MODE_CREATE.

  @param[in] FileName 		      Pointer to file name.
  @param[out] FileHandle		    Pointer to the file handle.
  @param[in] OpenMode		        The mode to open the file with.
  @param[in] Attributes		      The file's file attributes.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found 
                                on the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellOpenFileByName(
  IN CONST CHAR16		            *FilePath,
  OUT EFI_FILE_HANDLE           *FileHandle,
  IN UINT64                     OpenMode,
  IN UINT64                    	Attributes
  );

/**
  This function creates a directory.

  If return is EFI_SUCCESS, the Filehandle is the opened directory's handle; 
  otherwise, the Filehandle is NULL. If the directory already existed, this 
  function opens the existing directory.

  @param[in]  DirectoryName     Pointer to Directory name.
  @param[out] FileHandle        Pointer to the file handle.

  @retval EFI_SUCCESS		        The information was set.
  @retval EFI_INVALID_PARAMETER	One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED	      Could not open the file path.	
  @retval EFI_NOT_FOUND	        The specified file could not be found on the 
                                device or the file system could not be found 
                                on the device.
  @retval EFI_NO_MEDIA		      The device has no medium.
  @retval EFI_MEDIA_CHANGED	    The device has a different medium in it or the 
                                medium is no longer supported.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The file or medium is write protected.
  @retval EFI_ACCESS_DENIED	    The file was opened read only.
  @retval EFI_OUT_OF_RESOURCES	Not enough resources were available to open the 
                                file.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellCreateDirectory(
  IN CONST CHAR16             *DirectoryName,
  OUT EFI_FILE_HANDLE         *FileHandle
  );

/**
  This function reads information from an opened file.

  If FileHandle is not a directory, the function reads the requested number of 
  bytes from the file at the file's current position and returns them in Buffer. 
  If the read goes beyond the end of the file, the read length is truncated to the
  end of the file. The file's current position is increased by the number of bytes 
  returned.  If FileHandle is a directory, the function reads the directory entry 
  at the file's current position and returns the entry in Buffer. If the Buffer 
  is not large enough to hold the current directory entry, then 
  EFI_BUFFER_TOO_SMALL is returned and the current file position is not updated. 
  BufferSize is set to be the size of the buffer needed to read the entry. On 
  success, the current position is updated to the next directory entry. If there 
  are no more directory entries, the read returns a zero-length buffer. 
  EFI_FILE_INFO is the structure returned as the directory entry.

  @param[in] FileHandle         The opened file handle.
  @param[in] ReadSize           On input the size of buffer in bytes.  On return 
                                the number of bytes written.
  @param[out] Buffer            The buffer to put read data into.

  @retval EFI_SUCCESS	          Data was read.
  @retval EFI_NO_MEDIA	        The device has no media.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_BUFFER_TO_SMALL	  Buffer is too small. ReadSize contains required 
                                size.

**/
EFI_STATUS
EFIAPI
ShellReadFile(
  IN EFI_FILE_HANDLE            FileHandle,
  IN OUT UINTN                  *ReadSize,
  OUT VOID                      *Buffer
  );

/**
  Write data to a file.

  This function writes the specified number of bytes to the file at the current 
  file position. The current file position is advanced the actual number of bytes 
  written, which is returned in BufferSize. Partial writes only occur when there 
  has been a data error during the write attempt (such as "volume space full"). 
  The file is automatically grown to hold the data if required. Direct writes to 
  opened directories are not supported.

  @param[in] FileHandle         The opened file for writing.

  @param[in] BufferSize         On input the number of bytes in Buffer.  On output
                                the number of bytes written.

  @param[in] Buffer             The buffer containing data to write is stored.

  @retval EFI_SUCCESS	          Data was written.
  @retval EFI_UNSUPPORTED	      Writes to an open directory are not supported.
  @retval EFI_NO_MEDIA	        The device has no media.
  @retval EFI_DEVICE_ERROR	    The device reported an error.
  @retval EFI_VOLUME_CORRUPTED	The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED	  The device is write-protected.
  @retval EFI_ACCESS_DENIED	    The file was open for read only.
  @retval EFI_VOLUME_FULL	      The volume is full.
**/
EFI_STATUS
EFIAPI
ShellWriteFile(
  IN EFI_FILE_HANDLE            FileHandle,
  IN OUT UINTN                  *BufferSize,
  IN VOID                       *Buffer
  );

/** 
  Close an open file handle.

  This function closes a specified file handle. All "dirty" cached file data is 
  flushed to the device, and the file is closed. In all cases the handle is 
  closed.

  @param[in] FileHandle           The file handle to close.

  @retval EFI_SUCCESS             The file handle was closed sucessfully.
  @retval INVALID_PARAMETER      	One of the parameters has an invalid value.
**/
EFI_STATUS
EFIAPI
ShellCloseFile (
  IN EFI_FILE_HANDLE            *FileHandle
  );

/**
  Delete a file and close the handle

  This function closes and deletes a file. In all cases the file handle is closed.
  If the file cannot be deleted, the warning code EFI_WARN_DELETE_FAILURE is 
  returned, but the handle is still closed.

  @param[in] FileHandle             The file handle to delete.

  @retval EFI_SUCCESS               The file was closed sucessfully.
  @retval EFI_WARN_DELETE_FAILURE   The handle was closed, but the file was not 
                                    deleted.
  @retval INVALID_PARAMETER    	    One of the parameters has an invalid value.
**/
EFI_STATUS
EFIAPI
ShellDeleteFile (
  IN EFI_FILE_HANDLE		*FileHandle
  );

/**
  Set the current position in a file.

  This function sets the current file position for the handle to the position 
  supplied. With the exception of seeking to position 0xFFFFFFFFFFFFFFFF, only
  absolute positioning is supported, and seeking past the end of the file is 
  allowed (a subsequent write would grow the file). Seeking to position 
  0xFFFFFFFFFFFFFFFF causes the current position to be set to the end of the file.
  If FileHandle is a directory, the only position that may be set is zero. This 
  has the effect of starting the read process of the directory entries over.

  @param[in] FileHandle         The file handle on which the position is being set.

  @param[in] Position           Byte position from begining of file.

  @retval EFI_SUCCESS           Operation completed sucessfully.
  @retval EFI_UNSUPPORTED       The seek request for non-zero is not valid on 
                                directories.
  @retval INVALID_PARAMETER     One of the parameters has an invalid value.
**/
EFI_STATUS
EFIAPI
ShellSetFilePosition (
  IN EFI_FILE_HANDLE   	FileHandle,
  IN UINT64           	Position
  );

/** 
  Gets a file's current position

  This function retrieves the current file position for the file handle. For 
  directories, the current file position has no meaning outside of the file 
  system driver and as such the operation is not supported. An error is returned
  if FileHandle is a directory.

  @param[in] FileHandle         The open file handle on which to get the position.
  @param[out] Position          Byte position from begining of file.

  @retval EFI_SUCCESS           The operation completed sucessfully.
  @retval INVALID_PARAMETER     One of the parameters has an invalid value.
  @retval EFI_UNSUPPORTED       The request is not valid on directories.
**/
EFI_STATUS
EFIAPI
ShellGetFilePosition (
  IN EFI_FILE_HANDLE            FileHandle,
  OUT UINT64                    *Position
  );

/**
  Flushes data on a file
  
  This function flushes all modified data associated with a file to a device.

  @param[in] FileHandle         The file handle on which to flush data.

  @retval EFI_SUCCESS           The data was flushed.
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  @retval EFI_WRITE_PROTECTED   The file or medium is write protected.
  @retval EFI_ACCESS_DENIED     The file was opened for read only.
**/
EFI_STATUS
EFIAPI
ShellFlushFile (
  IN EFI_FILE_HANDLE            FileHandle
  );

/**
  Retrieves the first file from a directory

  This function takes an open directory handle and gets the first file 
  in the directory's info. Caller can use ShellFindNextFile() to get 
  subsequent files.

  Caller must use FreePool on *Buffer opon completion of all file searching.

  @param[in] DirHandle          The file handle of the directory to search
  @param[out] Buffer            Pointer to pointer to buffer for file's information

  @retval EFI_SUCCESS           Found the first file.
  @retval EFI_NOT_FOUND         Cannot find the directory.
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
  @return ShellReadFile
**/
EFI_STATUS
EFIAPI
ShellFindFirstFile (
  IN EFI_FILE_HANDLE            DirHandle,
  OUT EFI_FILE_INFO             **Buffer
  );

/**
  Retrieves the next file in a directory.

  To use this function, caller must call the ShellFindFirstFile() to get the 
  first file, and then use this function get other files. This function can be 
  called for several times to get each file's information in the directory. If 
  the call of ShellFindNextFile() got the last file in the directory, the next 
  call of this function has no file to get. *NoFile will be set to TRUE and the 
  data in Buffer is meaningless. 

  @param[in] DirHandle          The file handle of the directory.
  @param[out] Buffer			      Pointer to buffer for file's information.
  @param[out] NoFile			      Pointer to boolean when last file is found.

  @retval EFI_SUCCESS           Found the next file.
  @retval EFI_NO_MEDIA          The device has no media.
  @retval EFI_DEVICE_ERROR      The device reported an error.
  @retval EFI_VOLUME_CORRUPTED  The file system structures are corrupted.
**/
EFI_STATUS
EFIAPI
ShellFindNextFile(
  IN EFI_FILE_HANDLE             DirHandle,
  OUT EFI_FILE_INFO              *Buffer,
  OUT BOOLEAN                    *NoFile
  );

/**
  Retrieve the size of a file.

  This function extracts the file size info from the FileHandle's EFI_FILE_INFO 
  data.

  @param[in] FileHandle         The file handle from which size is retrieved.
  @param[out] Size              Pointer to size.

  @retval EFI_SUCCESS           The operation was completed sucessfully.
  @retval EFI_DEVICE_ERROR      Cannot access the file.
**/
EFI_STATUS
EFIAPI
ShellGetFileSize (
  IN EFI_FILE_HANDLE            FileHandle,
  OUT UINT64                    *Size
  );

/**
  Retrieves the status of the break execution flag

  This function is useful to check whether the application is being asked to halt by the shell.

  @retval TRUE                  the execution break is enabled
  @retval FALSE                 the execution break is not enabled
**/
BOOLEAN
EFIAPI
ShellGetExecutionBreakFlag(
  VOID
  );

/**
  Return the value of an environment variable.

  This function gets the value of the environment variable set by the 
  ShellSetEnvironmentVariable function.

  @param[in] EnvKey             The key name of the environment variable.

  @retval NULL                  The named environment variable does not exist.
  @return != NULL               pointer to the value of the environment variable.
**/
CONST CHAR16*
EFIAPI
ShellGetEnvironmentVariable (
  IN CONST CHAR16                *EnvKey
  );

/**
  Set the value of an environment variable.

  This function changes the current value of the specified environment variable. If the
  environment variable exists and the Value is an empty string, then the environment
  variable is deleted. If the environment variable exists and the Value is not an empty
  string, then the value of the environment variable is changed. If the environment
  variable does not exist and the Value is an empty string, there is no action. If the
  environment variable does not exist and the Value is a non-empty string, then the
  environment variable is created and assigned the specified value.

  This is not supported pre-UEFI Shell 2.0.

  @param[in] EnvKey             The key name of the environment variable.
  @param[in] EnvVal             The Value of the environment variable
  @param[in] Volatile           Indicates whether the variable is non-volatile (FALSE) or volatile (TRUE).

  @retval EFI_SUCCESS           the operation was completed sucessfully
  @retval EFI_UNSUPPORTED       This operation is not allowed in pre UEFI 2.0 Shell environments
**/
EFI_STATUS
EFIAPI
ShellSetEnvironmentVariable (
  IN CONST CHAR16               *EnvKey,
  IN CONST CHAR16               *EnvVal,
  IN BOOLEAN                    Volatile
  );

/**
  Cause the shell to parse and execute a command line.

  This function creates a nested instance of the shell and executes the specified
  command (CommandLine) with the specified environment (Environment). Upon return,
  the status code returned by the specified command is placed in StatusCode.
  If Environment is NULL, then the current environment is used and all changes made
  by the commands executed will be reflected in the current environment. If the
  Environment is non-NULL, then the changes made will be discarded.
  The CommandLine is executed from the current working directory on the current
  device.

  EnvironmentVariables and Status are only supported for UEFI Shell 2.0 (or later).
  Output is only supported for pre-UEFI Shell 2.0

  @param[in] ImageHandle          Parent image that is starting the operation.
  @param[in] CommandLine          Pointer to null terminated command line.
  @param[in] Output               True to display debug output.  False to hide it.
  @param[in] EnvironmentVariables Optional pointer to array of environment variables
                                  in the form "x=y".  If NULL current set is used.
  @param[out] Status              The status of the run command line.

  @retval EFI_SUCCESS             The operation completed sucessfully.  Status
                                  contains the status code returned.
  @retval EFI_INVALID_PARAMETER   A parameter contains an invalid value.
  @retval EFI_OUT_OF_RESOURCES    Out of resources.
  @retval EFI_UNSUPPORTED         The operation is not allowed.
**/
EFI_STATUS
EFIAPI
ShellExecute (
  IN EFI_HANDLE                 *ParentHandle,
  IN CHAR16                     *CommandLine,
  IN BOOLEAN                    Output,
  IN CHAR16                     **EnvironmentVariables,
  OUT EFI_STATUS                *Status
  );

/**
  Retreives the current directory path.

  If the DeviceName is NULL, it returns the current device's current directory 
  name. If the DeviceName is not NULL, it returns the current directory name 
  on specified drive.

  @param[in] DeviceName         The name of the file system to get directory on.

  @retval NULL                  The directory does not exist.
  @retval != NULL               The directory.
**/
CONST CHAR16*
EFIAPI
ShellGetCurrentDir (
  IN CHAR16                     *DeviceName OPTIONAL
  );

/**
  Sets (enabled or disabled) the page break mode.

  When page break mode is enabled the screen will stop scrolling 
  and wait for operator input before scrolling a subsequent screen.

  @param[in] CurrentState       TRUE to enable and FALSE to disable.
**/
VOID 
EFIAPI
ShellSetPageBreakMode (
  IN BOOLEAN                    CurrentState
  );

/**
  Opens a group of files based on a path.

  This function uses the Arg to open all the matching files. Each matched 
  file has a SHELL_FILE_ARG structure to record the file information. These 
  structures are placed on the list ListHead. Users can get the SHELL_FILE_ARG 
  structures from ListHead to access each file. This function supports wildcards
  and will process '?' and '*' as such.  The list must be freed with a call to 
  ShellCloseFileMetaArg().

  If you are NOT appending to an existing list *ListHead must be NULL.  If 
  *ListHead is NULL then it must be callee freed.

  @param[in] Arg                Pointer to path string.
  @param[in] OpenMode           Mode to open files with.
  @param[in] ListHead           Head of linked list of results.

  @retval EFI_SUCCESS           The operation was sucessful and the list head 
                                contains the list of opened files.
  @retval != EFI_SUCCESS        The operation failed.

  @sa InternalShellConvertFileListType
**/
EFI_STATUS
EFIAPI
ShellOpenFileMetaArg (
  IN CHAR16                     *Arg,
  IN UINT64                     OpenMode,
  IN OUT EFI_SHELL_FILE_INFO    **ListHead
  );

/**
  Free the linked list returned from ShellOpenFileMetaArg.

  @param[in] ListHead           The pointer to free.

  @retval EFI_SUCCESS           The operation was sucessful.
  @retval EFI_INVALID_PARAMETER A parameter was invalid.
**/
EFI_STATUS
EFIAPI
ShellCloseFileMetaArg (
  IN OUT EFI_SHELL_FILE_INFO    **ListHead
  );

/**
  Find a file by searching the CWD and then the path.

  If FileName is NULL, then ASSERT.

  If the return value is not NULL then the memory must be caller freed.

  @param[in] FileName           Filename string.

  @retval NULL                  The file was not found.
  @retval !NULL                 The path to the file.
**/
CHAR16 *
EFIAPI
ShellFindFilePath (
  IN CONST CHAR16 *FileName
  );

/**
  Find a file by searching the CWD and then the path with a variable set of file 
  extensions.  If the file is not found it will append each extension in the list 
  in the order provided and return the first one that is successful.

  If FileName is NULL, then ASSERT.
  If FileExtension is NULL, then behavior is identical to ShellFindFilePath.

  If the return value is not NULL then the memory must be caller freed.

  @param[in] FileName           Filename string.
  @param[in] FileExtension      Semi-colon delimeted list of possible extensions.

  @retval NULL                  The file was not found.
  @retval !NULL                 The path to the file.
**/
CHAR16 *
EFIAPI
ShellFindFilePathEx (
  IN CONST CHAR16 *FileName,
  IN CONST CHAR16 *FileExtension
  );

typedef enum {
  TypeFlag  = 0,    ///< A flag that is present or not present only (IE "-a").
  TypeValue,        ///< A flag that has some data following it with a space (IE "-a 1").
  TypePosition,     ///< Some data that did not follow a parameter (IE "filename.txt").
  TypeStart,        ///< A flag that has variable value appended to the end (IE "-ad", "-afd", "-adf", etc...).
  TypeDoubleValue,  ///< A flag that has 2 space seperated value data following it (IE "-a 1 2").
  TypeMaxValue,     ///< A flag followed by all the command line data before the next flag.
  TypeMax,
} ParamType;

typedef struct {
  CHAR16      *Name;
  ParamType   Type;
} SHELL_PARAM_ITEM;


/// Helper structure for no parameters (besides -? and -b)
extern SHELL_PARAM_ITEM EmptyParamList[];

/**
  Checks the command line arguments passed against the list of valid ones.  
  Optionally removes NULL values first.
  
  If no initialization is required, then return RETURN_SUCCESS.
  
  @param[in] CheckList          Pointer to list of parameters to check.
  @param[out] CheckPackage      Package of checked values.
  @param[out] ProblemParam      Optional pointer to pointer to unicode string for 
                                the paramater that caused failure.
  @param[in] AutoPageBreak      Will automatically set PageBreakEnabled.
  @param[in] AlwaysAllowNumbers Will never fail for number based flags.

  @retval EFI_SUCCESS           The operation completed sucessfully.
  @retval EFI_OUT_OF_RESOURCES  A memory allocation failed.
  @retval EFI_INVALID_PARAMETER A parameter was invalid.
  @retval EFI_VOLUME_CORRUPTED  The command line was corrupt.  An argument was 
                                duplicated.  The duplicated command line argument 
                                was returned in ProblemParam if provided.
  @retval EFI_DEVICE_ERROR      The commands contained 2 opposing arguments.  One
                                of the command line arguments was returned in 
                                ProblemParam if provided.
  @retval EFI_NOT_FOUND         A argument required a value that was missing.  
                                The invalid command line argument was returned in
                                ProblemParam if provided.
**/
EFI_STATUS
EFIAPI
ShellCommandLineParseEx (
  IN CONST SHELL_PARAM_ITEM     *CheckList,
  OUT LIST_ENTRY                **CheckPackage,
  OUT CHAR16                    **ProblemParam OPTIONAL,
  IN BOOLEAN                    AutoPageBreak,
  IN BOOLEAN                    AlwaysAllowNumbers
  );

/// Make it easy to upgrade from older versions of the shell library.
#define ShellCommandLineParse(CheckList,CheckPackage,ProblemParam,AutoPageBreak) ShellCommandLineParseEx(CheckList,CheckPackage,ProblemParam,AutoPageBreak,FALSE)

/**
  Frees shell variable list that was returned from ShellCommandLineParse.

  This function will free all the memory that was used for the CheckPackage
  list of postprocessed shell arguments.

  If CheckPackage is NULL, then return.

  @param[in] CheckPackage       The list to de-allocate.
  **/
VOID
EFIAPI
ShellCommandLineFreeVarList (
  IN LIST_ENTRY                 *CheckPackage
  );

/**
  Checks for presence of a flag parameter.

  Flag arguments are in the form of "-<Key>" or "/<Key>", but do not have a value following the key.

  If CheckPackage is NULL then return FALSE.
  If KeyString is NULL then ASSERT().
  
  @param[in] CheckPackage       The package of parsed command line arguments.
  @param[in] KeyString          The Key of the command line argument to check for.

  @retval TRUE                  The flag is on the command line.
  @retval FALSE                 The flag is not on the command line.
  **/
BOOLEAN
EFIAPI
ShellCommandLineGetFlag (
  IN CONST LIST_ENTRY              *CheckPackage,
  IN CHAR16                        *KeyString
  );

/**
  Returns value from command line argument.

  Value parameters are in the form of "-<Key> value" or "/<Key> value".
  
  If CheckPackage is NULL, then return NULL.

  @param[in] CheckPackage       The package of parsed command line arguments.
  @param[in] KeyString          The Key of the command line argument to check for.

  @retval NULL                  The flag is not on the command line.
  @retval !=NULL                Pointer to unicode string of the value.
  **/
CONST CHAR16*
EFIAPI
ShellCommandLineGetValue (
  IN CONST LIST_ENTRY              *CheckPackage,
  IN CHAR16                        *KeyString
  );

/**
  Returns raw value from command line argument.

  Raw value parameters are in the form of "value" in a specific position in the list.
  
  If CheckPackage is NULL, then return NULL.

  @param[in] CheckPackage       The package of parsed command line arguments.
  @param[in] Position           The position of the value.

  @retval NULL                  The flag is not on the command line.
  @retval !=NULL                Pointer to unicode string of the value.
  **/
CONST CHAR16*
EFIAPI
ShellCommandLineGetRawValue (
  IN CONST LIST_ENTRY              *CheckPackage,
  IN UINT32                        Position
  );

/**
  Returns the number of command line value parameters that were parsed.  
  
  This will not include flags.

  @retval (UINTN)-1     No parsing has ocurred.
  @return               The number of value parameters found.
**/
UINTN
EFIAPI
ShellCommandLineGetCount(
  VOID
  );

/**
  Determins if a parameter is duplicated.

  If Param is not NULL then it will point to a callee allocated string buffer 
  with the parameter value if a duplicate is found.

  If CheckPackage is NULL, then ASSERT.

  @param[in] CheckPackage       The package of parsed command line arguments.
  @param[out] Param             Upon finding one, a pointer to the duplicated parameter.

  @retval EFI_SUCCESS           No parameters were duplicated.
  @retval EFI_DEVICE_ERROR      A duplicate was found.
  **/
EFI_STATUS
EFIAPI
ShellCommandLineCheckDuplicate (
  IN CONST LIST_ENTRY              *CheckPackage,
  OUT CHAR16                       **Param
  );

/**
  This function causes the shell library to initialize itself.  If the shell library
  is already initialized it will de-initialize all the current protocol poitners and
  re-populate them again.

  When the library is used with PcdShellLibAutoInitialize set to true this function
  will return EFI_SUCCESS and perform no actions.

  This function is intended for internal access for shell commands only.

  @retval EFI_SUCCESS   the initialization was complete sucessfully

**/
EFI_STATUS
EFIAPI
ShellInitialize (
  VOID
  );

/**
  Print at a specific location on the screen.

  This function will move the cursor to a given screen location and print the specified string.
  
  If -1 is specified for either the Row or Col the current screen location for BOTH 
  will be used.

  If either Row or Col is out of range for the current console, then ASSERT.
  If Format is NULL, then ASSERT.

  In addition to the standard %-based flags as supported by UefiLib Print() this supports 
  the following additional flags:
    %N       -   Set output attribute to normal
    %H       -   Set output attribute to highlight
    %E       -   Set output attribute to error
    %B       -   Set output attribute to blue color
    %V       -   Set output attribute to green color

  Note: The background color is controlled by the shell command cls.

  @param[in] Row        The row to print at.
  @param[in] Col        The column to print at.
  @param[in] Format     The format string.

  @return The number of characters printed to the screen.
**/

UINTN
EFIAPI
ShellPrintEx(
  IN INT32                Col OPTIONAL,
  IN INT32                Row OPTIONAL,
  IN CONST CHAR16         *Format,
  ...
  );

/**
  Print at a specific location on the screen.

  This function will move the cursor to a given screen location and print the specified string.
  
  If -1 is specified for either the Row or Col the current screen location for BOTH 
  will be used.

  If either Row or Col is out of range for the current console, then ASSERT.
  If Format is NULL, then ASSERT.

  In addition to the standard %-based flags as supported by UefiLib Print() this supports 
  the following additional flags:
    %N       -   Set output attribute to normal.
    %H       -   Set output attribute to highlight.
    %E       -   Set output attribute to error.
    %B       -   Set output attribute to blue color.
    %V       -   Set output attribute to green color.

  Note: The background color is controlled by the shell command cls.

  @param[in] Row                The row to print at.
  @param[in] Col                The column to print at.
  @param[in] HiiFormatStringId  The format string Id for getting from Hii.
  @param[in] HiiFormatHandle    The format string Handle for getting from Hii.

  @return the number of characters printed to the screen.
**/
UINTN
EFIAPI
ShellPrintHiiEx(
  IN INT32                Col OPTIONAL,
  IN INT32                Row OPTIONAL,
  IN CONST EFI_STRING_ID  HiiFormatStringId,
  IN CONST EFI_HANDLE     HiiFormatHandle,
  ...
  );

/**
  Function to determine if a given filename represents a directory.

  If DirName is NULL, then ASSERT.

  @param[in] DirName      Path to directory to test.

  @retval EFI_SUCCESS     The Path represents a directory.
  @retval EFI_NOT_FOUND   The Path does not represent a directory.
  @retval other           The path failed to open.
**/
EFI_STATUS
EFIAPI
ShellIsDirectory(
  IN CONST CHAR16 *DirName
  );

/**
  Function to determine if a given filename represents a file.

  This will search the CWD only.

  If Name is NULL, then ASSERT.

  @param[in] Name         Path to file to test.

  @retval EFI_SUCCESS     The Path represents a file.
  @retval EFI_NOT_FOUND   The Path does not represent a file.
  @retval other           The path failed to open.
**/
EFI_STATUS
EFIAPI
ShellIsFile(
  IN CONST CHAR16 *Name
  );

/**
  Function to determine if a given filename represents a file.

  This will search the CWD and then the Path.

  If Name is NULL, then ASSERT.

  @param[in] Name         Path to file to test.

  @retval EFI_SUCCESS     The Path represents a file.
  @retval EFI_NOT_FOUND   The Path does not represent a file.
  @retval other           The path failed to open.
**/
EFI_STATUS
EFIAPI
ShellIsFileInPath(
  IN CONST CHAR16 *Name
  );

/**
  Function to determine whether a string is decimal or hex representation of a number 
  and return the number converted from the string.

  @param[in] String   String representation of a number

  @return             The unsigned integer result of the conversion.
**/
UINTN
EFIAPI
ShellStrToUintn(
  IN CONST CHAR16 *String
  );

/**
  Safely append with automatic string resizing given length of Destination and 
  desired length of copy from Source.

  Append the first D characters of Source to the end of Destination, where D is 
  the lesser of Count and the StrLen() of Source. If appending those D characters 
  will fit within Destination (whose Size is given as CurrentSize) and 
  still leave room for a null terminator, then those characters are appended, 
  starting at the original terminating null of Destination, and a new terminating 
  null is appended.

  If appending D characters onto Destination will result in a overflow of the size
  given in CurrentSize the string will be grown such that the copy can be performed
  and CurrentSize will be updated to the new size.

  If Source is NULL, there is nothing to append, just return the current buffer in 
  Destination.

  If Destination is NULL, then ASSERT().
  If Destination's current length (including NULL terminator) is already more than 
  CurrentSize, then ASSERT().

  @param[in,out] Destination    The String to append onto.
  @param[in,out] CurrentSize    On call the number of bytes in Destination.  On 
                                return possibly the new size (still in bytes).  If NULL
                                then allocate whatever is needed.
  @param[in]     Source         The String to append from.
  @param[in]     Count          Maximum number of characters to append.  If 0 then 
                                all are appended.

  @return                       The Destination after apending the Source.
**/
CHAR16* 
EFIAPI
StrnCatGrow (
  IN OUT CHAR16           **Destination,
  IN OUT UINTN            *CurrentSize,
  IN     CONST CHAR16     *Source,
  IN     UINTN            Count
  );

/**
  This is a find and replace function.  Upon successful return the NewString is a copy of 
  SourceString with each instance of FindTarget replaced with ReplaceWith.

  If SourceString and NewString overlap the behavior is undefined.

  If the string would grow bigger than NewSize it will halt and return error.

  @param[in] SourceString             String with source buffer.
  @param[in,out] NewString            String with resultant buffer.
  @param[in] NewSize                  Size in bytes of NewString.
  @param[in] FindTarget               String to look for.
  @param[in] ReplaceWith              String to replace FindTarget with.

  @retval EFI_INVALID_PARAMETER       SourceString was NULL.
  @retval EFI_INVALID_PARAMETER       NewString was NULL.
  @retval EFI_INVALID_PARAMETER       FindTarget was NULL.
  @retval EFI_INVALID_PARAMETER       ReplaceWith was NULL.
  @retval EFI_INVALID_PARAMETER       FindTarget had length < 1.
  @retval EFI_INVALID_PARAMETER       SourceString had length < 1.
  @retval EFI_BUFFER_TOO_SMALL        NewSize was less than the minimum size to hold 
                                      the new string (truncation occurred).
  @retval EFI_SUCCESS                 the string was sucessfully copied with replacement.
**/

EFI_STATUS
EFIAPI
ShellLibCopySearchAndReplace(
  IN CHAR16 CONST                     *SourceString,
  IN CHAR16                           *NewString,
  IN UINTN                            NewSize,
  IN CONST CHAR16                     *FindTarget,
  IN CONST CHAR16                     *ReplaceWith
  );

/**
  Check if a Unicode character is a hexadecimal character.

  This internal function checks if a Unicode character is a 
  decimal character.  The valid hexadecimal character is 
  L'0' to L'9', L'a' to L'f', or L'A' to L'F'.

  @param[in]  Char  The character to check.

  @retval TRUE      The Char is a hexadecmial character.
  @retval FALSE     The Char is not a hexadecmial character.

**/
BOOLEAN
EFIAPI
ShellLibIsHexaDecimalDigitCharacter (
  IN      CHAR16                    Char
  );

#endif // __SHELL_LIB__