edk2/ShellPkg/Library/UefiShellDebug1CommandsLib/HexEdit/Misc.h
Michael Kubacki 8472271dae ShellPkg: Replace include guards with #pragma once
Replace traditional `#ifndef`/`#define`/`#endif` include guards with
`#pragma` once.

`#pragma once` is a widely supported preprocessor directive that
prevents header files from being included multiple times. It is
supported by all toolchains used to build edk2: GCC, Clang/LLVM, and
MSVC.

Compared to macro-based include guards, `#pragma once`:

- Eliminates the risk of macro name collisions or copy/paste errors
  where two headers inadvertently use the same guard macro.
- Eliminate inconsistency in the way include guard macros are named
  (e.g., some files use `__FILE_H__`, others use `FILE_H_`, etc.).
- Reduces boilerplate (three lines replaced by one).
- Avoids polluting the macro namespace with guard symbols.
- Can improve build times as the preprocessor can skip re-opening the
  file entirely, rather than re-reading it to find the matching
  `#endif` ("multiple-include optimization").
  - Note that some compilers may already optimize traditional include
    guards, by recognzining the idiomatic pattern.

This change is made acknowledging that overall portability of the
code will technically be reduced, as `#pragma once` is not part of the
C/C++ standards.

However, this is considered acceptable given:

1. edk2 already defines a subset of supported compilers in
   BaseTools/Conf/tools_def.template, all of which have supported
   `#pragma once` for over two decades.
2. There have been concerns raised to the project about inconsistent
   include guard naming and potential macro collisions.

Approximate compiler support dates:

- MSVC: Supported since Visual C++ 4.2 (1996)
- GCC: Supported since 3.4 (2004)
  (http://gnu.ist.utl.pt/software/gcc/gcc-3.4/changes.html)
- Clang (LLVM based): Since initial release in 2007

Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>
2026-02-23 21:01:28 +00:00

84 lines
1.6 KiB
C

/** @file
Definitions for various line and string routines
Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved. <BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#pragma once
#include "HexEditor.h"
/**
Advance/Retreat lines.
@param[in] Count The line number to advance/retreat.
>0 : advance
<0: retreat
@retval NULL An error occurred.
@return A pointer to the line after move.
**/
HEFI_EDITOR_LINE *
HMoveLine (
IN INTN Count
);
/**
Advance/Retreat lines and set CurrentLine in BufferImage to it.
@param[in] Count The line number to advance/retreat.
>0 : advance
<0: retreat
@retval NULL An error occurred.
@return A pointer to the line after move.
**/
HEFI_EDITOR_LINE *
HMoveCurrentLine (
IN INTN Count
);
/**
Free all the lines in HBufferImage.
Fields affected:
Lines
CurrentLine
NumLines
ListHead
@param[in] ListHead The list head.
@param[in] Lines The lines.
@retval EFI_SUCCESS The operation was successful.
**/
EFI_STATUS
HFreeLines (
IN LIST_ENTRY *ListHead,
IN HEFI_EDITOR_LINE *Lines
);
/**
Get the X information for the mouse.
@param[in] GuidX The change.
@return the new information.
**/
INT32
HGetTextX (
IN INT32 GuidX
);
/**
Get the Y information for the mouse.
@param[in] GuidY The change.
@return the new information.
**/
INT32
HGetTextY (
IN INT32 GuidY
);