Files
edk2-upstream/MdeModulePkg/Include/Library/CpuExceptionHandlerLib.h
Michael Kubacki 7a934d0bef MdeModulePkg: 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

100 lines
4.1 KiB
C

/** @file
CPU Exception library provides the default CPU interrupt/exception handler.
It also provides capability to register user interrupt/exception handler.
Copyright (c) 2012 - 2022, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#pragma once
#include <Ppi/VectorHandoffInfo.h>
#include <Protocol/Cpu.h>
/**
Initializes all CPU exceptions entries and provides the default exception handlers.
Caller should try to get an array of interrupt and/or exception vectors that are in use and need to
persist by EFI_VECTOR_HANDOFF_INFO defined in PI 1.3 specification.
If caller cannot get reserved vector list or it does not exists, set VectorInfo to NULL.
If VectorInfo is not NULL, the exception vectors will be initialized per vector attribute accordingly.
@param[in] VectorInfo Pointer to reserved vector list.
@retval EFI_SUCCESS CPU Exception Entries have been successfully initialized
with default exception handlers.
@retval EFI_INVALID_PARAMETER VectorInfo includes the invalid content if VectorInfo is not NULL.
@retval EFI_UNSUPPORTED This function is not supported.
**/
EFI_STATUS
EFIAPI
InitializeCpuExceptionHandlers (
IN EFI_VECTOR_HANDOFF_INFO *VectorInfo OPTIONAL
);
/**
Setup separate stacks for certain exception handlers.
If the input Buffer and BufferSize are both NULL, use global variable if possible.
@param[in] Buffer Point to buffer used to separate exception stack.
@param[in, out] BufferSize On input, it indicates the byte size of Buffer.
If the size is not enough, the return status will
be EFI_BUFFER_TOO_SMALL, and output BufferSize
will be the size it needs.
@retval EFI_SUCCESS The stacks are assigned successfully.
@retval EFI_UNSUPPORTED This function is not supported.
@retval EFI_BUFFER_TOO_SMALL This BufferSize is too small.
**/
EFI_STATUS
EFIAPI
InitializeSeparateExceptionStacks (
IN VOID *Buffer,
IN OUT UINTN *BufferSize
);
/**
Registers a function to be called from the processor interrupt handler.
This function registers and enables the handler specified by InterruptHandler for a processor
interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the
handler for the processor interrupt or exception type specified by InterruptType is uninstalled.
The installed handler is called once for each processor interrupt or exception.
NOTE: This function should be invoked after InitializeCpuExceptionHandlers() is invoked,
otherwise EFI_UNSUPPORTED returned.
@param[in] InterruptType Defines which interrupt or exception to hook.
@param[in] InterruptHandler A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
when a processor interrupt occurs. If this parameter is NULL, then the handler
will be uninstalled.
@retval EFI_SUCCESS The handler for the processor interrupt was successfully installed or uninstalled.
@retval EFI_ALREADY_STARTED InterruptHandler is not NULL, and a handler for InterruptType was
previously installed.
@retval EFI_INVALID_PARAMETER InterruptHandler is NULL, and a handler for InterruptType was not
previously installed.
@retval EFI_UNSUPPORTED The interrupt specified by InterruptType is not supported,
or this function is not supported.
**/
EFI_STATUS
EFIAPI
RegisterCpuInterruptHandler (
IN EFI_EXCEPTION_TYPE InterruptType,
IN EFI_CPU_INTERRUPT_HANDLER InterruptHandler
);
/**
Display processor context.
@param[in] ExceptionType Exception type.
@param[in] SystemContext Processor context to be display.
**/
VOID
EFIAPI
DumpCpuContext (
IN EFI_EXCEPTION_TYPE ExceptionType,
IN EFI_SYSTEM_CONTEXT SystemContext
);