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edk2/ShellPkg/Library/UefiShellMyWriteCommandsLib/UefiShellMyWriteCommandsLib.inf

##  @file
# Provides shell my write functions
#
#
#
##

[Defines]
  INF_VERSION                    = 0x00010006
  BASE_NAME                      = UefiShellMyWriteCommandsLib
  FILE_GUID                      = 9A933F7E-3861-45ce-87AB-7221219AE255
  MODULE_TYPE                    = UEFI_APPLICATION
  VERSION_STRING                 = 1.0
  LIBRARY_CLASS                  = NULL|UEFI_APPLICATION UEFI_DRIVER
  CONSTRUCTOR                    = ShellMyWriteCommandsLibConstructor
  DESTRUCTOR                     = ShellMyWriteCommandsLibDestructor

[Sources.common]
  MyWriteCmd.c
  UefiShellMyWriteCommandsLib.uni
  UefiShellMyWriteCommandsLib.c
  UefiShellMyWriteCommandsLib.h

[Packages]
  MdePkg/MdePkg.dec
  ShellPkg/ShellPkg.dec
  MdeModulePkg/MdeModulePkg.dec

[LibraryClasses]
  MemoryAllocationLib
  BaseLib
  BaseMemoryLib
  DebugLib
  ShellCommandLib
  ShellLib
  UefiLib
  UefiRuntimeServicesTableLib
  UefiBootServicesTableLib
  PcdLib
  HiiLib
  FileHandleLib

[Pcd]
  gEfiShellPkgTokenSpaceGuid.PcdShellProfileMask ## CONSUMES

[Protocols]
 

[Guids]
  gShellMyWriteHiiGuid                         ## SOMETIMES_CONSUMES ## HII

edk2/ShellPkg/Library/UefiShellMyWriteCommandsLib/UefiShellMyWriteCommandsLib.c

/** @file
  Main file for NULL named library for My Write shell command functions.
**
**
**/

#include "UefiShellMyWriteCommandsLib.h"


#include "UefiShellMyWriteCommandsLib.h"

CONST CHAR16 gShelMyWriteFileName[] = L"ShellMyWriteCommands";
EFI_HII_HANDLE gShellMyWriteHiiHandle = NULL;

/**
  return the file name of the help text file if not using HII.

  @return The string pointer to the file name.
**/
CONST CHAR16*
EFIAPI
ShellCommandGetManFileNameMyWrite (
  VOID
  )
{
  return (gShelMyWriteFileName);
}

/**
  Constructor for the Shell My Write Commands library.

  Install the handlers for My Write UEFI Shell 2.0 profile commands.

  @param ImageHandle            The image handle of the process.
  @param SystemTable            The EFI System Table pointer.

  @retval EFI_SUCCESS           The shell command handlers were installed sucessfully.
  @retval EFI_UNSUPPORTED       The shell level required was not found.
**/
EFI_STATUS
EFIAPI
ShellMyWriteCommandsLibConstructor (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  gShellMyWriteHiiHandle = NULL;

  //
  // check our bit of the profiles mask
  //
  if ((PcdGet8(PcdShellProfileMask) & BIT3) == 0) {
    return (EFI_SUCCESS);
  }

  gShellMyWriteHiiHandle = HiiAddPackages (
                             &gShellMyWriteHiiGuid,
                             gImageHandle,
                             UefiShellMyWriteCommandsLibStrings,
                             NULL
                             );
  if (gShellMyWriteHiiHandle == NULL) {
    return (EFI_DEVICE_ERROR);
  }
  //
  // install our shell command handlers
  //
  ShellCommandRegisterCommandName(
    L"MyWriteCmd",    
    ShellCommandRunMyWrite,
    ShellCommandGetManFileNameMyWrite,
    0,
    L"MyWriteCmd",
    TRUE,
    gShellMyWriteHiiHandle,
    STRING_TOKEN(STR_MY_WRITE_HELP_PING)
    );

  return (EFI_SUCCESS);
}

/**
  Destructor for the library.  free any resources.

  @param ImageHandle            The image handle of the process.
  @param SystemTable            The EFI System Table pointer.
**/
EFI_STATUS
EFIAPI
ShellMyWriteCommandsLibDestructor (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  )
{
  if (gShellMyWriteHiiHandle != NULL) {
    HiiRemovePackages(gShellMyWriteHiiHandle);
  }
  return (EFI_SUCCESS);
}

edk2/ShellPkg/Library/UefiShellMyWriteCommandsLib/UefiShellMyWriteCommandsLib.h

/** @file
  header file for NULL named library for my write shell command functions.

**/

#ifndef _UEFI_SHELL_MYWRITE_COMMANDS_LIB_H_
#define _UEFI_SHELL_MYWRITE_COMMANDS_LIB_H_

#include <Uefi.h>

#include <Guid/ShellLibHiiGuid.h>

#include <Protocol/Cpu.h>
#include <Protocol/ServiceBinding.h>
#include <Protocol/Arp.h>

#include <Library/BaseLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/PcdLib.h>
#include <Library/ShellCommandLib.h>
#include <Library/ShellLib.h>
#include <Library/SortLib.h>
#include <Library/UefiLib.h>
#include <Library/UefiRuntimeServicesTableLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/HiiLib.h>
#include <Library/DevicePathLib.h>
#include <Library/PrintLib.h>

extern EFI_HII_HANDLE gShellMyWriteHiiHandle;

/**
  Function for 'ping' command.

  @param[in] ImageHandle  Handle to the Image (NULL if Internal).
  @param[in] SystemTable  Pointer to the System Table (NULL if Internal).
**/
SHELL_STATUS
EFIAPI
ShellCommandRunMyWrite (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  );

#endif

edk2/ShellPkg/Library/UefiShellMyWriteCommandsLib/UefiShellMyWriteCommandsLib.uni

// /**
//
//
//
//
// String definitions for UEFI Shell 2.0 my write commands
//
//
// **/

/=#

#langdef   en-US "english"

#string STR_MY_WRITE_HELP_PING         #language en-US ""
"------------------------------------------\r\n"
"------------------------------------------\r\n"
"test write uefi shell cmd for help !!! ...\r\n"
"------------------------------------------\r\n"
"------------------------------------------\r\n"

edk2/ShellPkg/Library/UefiShellMyWriteCommandsLib/MyWriteCmd.c

/** @file
  The implementation for Shell command my write

  (C) Copyright 2013-2015 Hewlett-Packard Development Company, L.P.<BR>
  Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>

  SPDX-License-Identifier: BSD-2-Clause-Patent

**/

#include "UefiShellMyWriteCommandsLib.h"

STATIC CONST SHELL_PARAM_ITEM ParamList[] = {
  {L"-v", TypeValue},
  {L"-h", TypeValue},
  {NULL, TypeMax}
  };

/**
  Function for my write command.

  @param[in]  ImageHandle           Handle to the Image (NULL if Internal).
  @param[in]  SystemTable           Pointer to the System Table (NULL if Internal).

  @retval  SHELL_SUCCESS            The command completed successfully.
  @retval  Others                   The command failed.

**/
SHELL_STATUS
EFIAPI
ShellCommandRunMyWrite (
  IN  EFI_HANDLE                    ImageHandle,
  IN  EFI_SYSTEM_TABLE              *SystemTable
  )
{
  EFI_STATUS                      Status;
  LIST_ENTRY                      *CheckPackage;
  CHAR16                  *ProblemParam;

  Status = ShellInitialize ();
  ASSERT_EFI_ERROR (Status);

  Status = ShellCommandLineParse (ParamList, &CheckPackage, &ProblemParam, TRUE);
  ASSERT_EFI_ERROR (Status);

  if (ShellCommandLineGetFlag (CheckPackage, L"-v")) {
    ShellPrintEx (-1, -1, L"%V v1.0 %N\r\n");
    return SHELL_SUCCESS;
  }
 
  if (ShellCommandLineGetFlag (CheckPackage, L"-h")) {
      //ShellPrintEx (-1, -1, L"%V my write cmd for help... %N\r\n");
      ShellPrintHiiEx (-1, -1, NULL, STRING_TOKEN (STR_MY_WRITE_HELP_PING), gShellMyWriteHiiHandle, L"MyWriteCmd");
      return SHELL_SUCCESS;
  }

  Print (L"this is my write cmd !\n");

  return SHELL_SUCCESS;
}

edk2/OvmfPkg/OvmfPkgX64.dsc

    <LibraryClasses>
      ShellCommandLib|ShellPkg/Library/UefiShellCommandLib/UefiShellCommandLib.inf
      NULL|ShellPkg/Library/UefiShellLevel2CommandsLib/UefiShellLevel2CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellLevel1CommandsLib/UefiShellLevel1CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellLevel3CommandsLib/UefiShellLevel3CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellDriver1CommandsLib/UefiShellDriver1CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellDebug1CommandsLib/UefiShellDebug1CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellInstall1CommandsLib/UefiShellInstall1CommandsLib.inf
      NULL|ShellPkg/Library/UefiShellNetwork1CommandsLib/UefiShellNetwork1CommandsLib.inf

#my write ...
      NULL|ShellPkg/Library/UefiShellMyWriteCommandsLib/UefiShellMyWriteCommandsLib.inf
#my write ....