edk2/MdeModulePkg/Include/Guid/RngAlgorithm.h

/** @file
  Rng Algorithm

  Copyright (c) 2023, Arm Limited. All rights reserved.<BR>
  SPDX-License-Identifier: BSD-2-Clause-Patent
**/

#pragma once

///
/// The implementation of a Random Number Generator might be unsafe, when using
/// a dummy implementation for instance. Allow identifying such implementation
/// with this GUID.
///
#define EDKII_RNG_ALGORITHM_UNSAFE \
  { \
    0x869f728c, 0x409d, 0x4ab4, {0xac, 0x03, 0x71, 0xd3, 0x09, 0xc1, 0xb3, 0xf4 } \
  }

extern EFI_GUID  gEdkiiRngAlgorithmUnSafe;
MdeModulePkg/Rng: Add GUID to describe unsafe Rng algorithms BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4441 The EFI_RNG_PROTOCOL can rely on the RngLib. The RngLib has multiple implementations, some of them are unsafe (e.g. BaseRngLibTimerLib). To allow the RngDxe to detect when such implementation is used, a GetRngGuid() function is added in a following patch. Prepare GetRngGuid() return values and add a gEdkiiRngAlgorithmUnSafe to describe an unsafe implementation, cf. the BaseRngLibTimerLib. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Reviewed-by: Sami Mujawar <sami.mujawar@arm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Kun Qin <kun.qin@microsoft.com> 2023-08-11 16:33:07 +02:00			`/** @file`
			`Rng Algorithm`

			`Copyright (c) 2023, Arm Limited. All rights reserved.<BR>`
			`SPDX-License-Identifier: BSD-2-Clause-Patent`
			`**/`

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> 2026-02-03 13:48:28 -05:00			`#pragma once`
MdeModulePkg/Rng: Add GUID to describe unsafe Rng algorithms BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4441 The EFI_RNG_PROTOCOL can rely on the RngLib. The RngLib has multiple implementations, some of them are unsafe (e.g. BaseRngLibTimerLib). To allow the RngDxe to detect when such implementation is used, a GetRngGuid() function is added in a following patch. Prepare GetRngGuid() return values and add a gEdkiiRngAlgorithmUnSafe to describe an unsafe implementation, cf. the BaseRngLibTimerLib. Signed-off-by: Pierre Gondois <pierre.gondois@arm.com> Reviewed-by: Sami Mujawar <sami.mujawar@arm.com> Acked-by: Ard Biesheuvel <ardb@kernel.org> Tested-by: Kun Qin <kun.qin@microsoft.com> 2023-08-11 16:33:07 +02:00
			`///`
			`/// The implementation of a Random Number Generator might be unsafe, when using`
			`/// a dummy implementation for instance. Allow identifying such implementation`
			`/// with this GUID.`
			`///`
			`#define EDKII_RNG_ALGORITHM_UNSAFE \`
			`{ \`
			`0x869f728c, 0x409d, 0x4ab4, {0xac, 0x03, 0x71, 0xd3, 0x09, 0xc1, 0xb3, 0xf4 } \`
			`}`

			`extern EFI_GUID gEdkiiRngAlgorithmUnSafe;`