CryptoPkg: 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.

Does not include updates to OpenSSL generated header files checked
into the repo. Those in `CryptoPkg\Library\OpensslLib\OpensslGen\`.

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>

CryptoPkg/Include/Library/BaseCryptLib.h

@@ -10,8 +10,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __BASE_CRYPT_LIB_H__
-#define __BASE_CRYPT_LIB_H__
+#pragma once
 
 #include <Uefi/UefiBaseType.h>
 
@@ -4302,5 +4301,3 @@ EcDsaVerify (
   IN  CONST UINT8  *Signature,
   IN  UINTN        SigSize
   );
-
-#endif // __BASE_CRYPT_LIB_H__

CryptoPkg/Include/Library/HashApiLib.h

@@ -9,8 +9,7 @@
 
 **/
 
-#ifndef __HASH_API_LIB_H_
-#define __HASH_API_LIB_H_
+#pragma once
 
 typedef VOID *HASH_API_CONTEXT;
 
@@ -106,5 +105,3 @@ HashApiHashAll (
   IN  UINTN       DataToHashLen,
   OUT UINT8       *Digest
   );
-
-#endif

CryptoPkg/Include/Library/TlsLib.h

@@ -6,8 +6,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __TLS_LIB_H__
-#define __TLS_LIB_H__
+#pragma once
 
 /**
   Initializes the OpenSSL library.
@@ -968,5 +967,3 @@ TlsGetExportKey (
   OUT    VOID        *KeyBuffer,
   IN     UINTN       KeyBufferLen
   );
-
-#endif // __TLS_LIB_H__

CryptoPkg/Include/Pcd/PcdCryptoServiceFamilyEnable.h

@@ -28,8 +28,7 @@
 
 **/
 
-#ifndef __PCD_CRYPTO_SERVICE_FAMILY_ENABLE_H__
-#define __PCD_CRYPTO_SERVICE_FAMILY_ENABLE_H__
+#pragma once
 
 ///
 /// Define used to enable all the crypto services in a family
@@ -431,5 +430,3 @@ typedef struct {
     UINT32    Family;
   } Ec;
 } PCD_CRYPTO_SERVICE_FAMILY_ENABLE;
-
-#endif

CryptoPkg/Library/BaseCryptLib/Hash/CryptParallelHash.h

@@ -21,8 +21,7 @@ and related or neighboring rights to the source code in this file.
 http://creativecommons.org/publicdomain/zero/1.0/
 **/
 
-#ifndef CRYPT_PARALLEL_HASH_H_
-#define CRYPT_PARALLEL_HASH_H_
+#pragma once
 
 #include "InternalCryptLib.h"
 
@@ -228,5 +227,3 @@ EFIAPI
 DispatchBlockToAp (
   VOID
   );
-
-#endif // CRYPT_PARALLEL_HASH_H_

CryptoPkg/Library/BaseCryptLib/InternalCryptLib.h

@@ -6,8 +6,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __INTERNAL_CRYPT_LIB_H__
-#define __INTERNAL_CRYPT_LIB_H__
+#pragma once
 
 #undef _WIN32
 #undef _WIN64
@@ -60,5 +59,3 @@ WrapPkcs7Data (
   OUT UINT8        **WrapData,
   OUT UINTN        *WrapDataSize
   );
-
-#endif

CryptoPkg/Library/BaseCryptLibMbedTls/InternalCryptLib.h

@@ -6,8 +6,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef INTERNAL_CRYPT_LIB_H_
-#define INTERNAL_CRYPT_LIB_H_
+#pragma once
 
 #include <Library/BaseLib.h>
 #include <Library/BaseMemoryLib.h>
@@ -70,5 +69,3 @@ WrapPkcs7Data (
   OUT UINT8        **WrapData,
   OUT UINTN        *WrapDataSize
   );
-
-#endif

CryptoPkg/Library/BaseCryptLibMbedTls/Pk/CryptPkcs7Internal.h

@@ -9,8 +9,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef CRYPT_PKCS7_INTERNAL_H_
-#define CRYPT_PKCS7_INTERNAL_H_
+#pragma once
 
 #include "InternalCryptLib.h"
 
@@ -85,5 +84,3 @@ typedef struct MbedtlsPkcs7 {
         else                                            \
             (g) += Ret;                                 \
     } while( 0 )
-
-#endif

CryptoPkg/Library/BaseCryptLibNull/InternalCryptLib.h

@@ -6,11 +6,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __INTERNAL_CRYPT_LIB_H__
-#define __INTERNAL_CRYPT_LIB_H__
+#pragma once
 
 #include <Base.h>
 #include <Library/BaseCryptLib.h>
 #include <Library/DebugLib.h>
-
-#endif

CryptoPkg/Library/Include/CrtLibSupport.h

@@ -9,8 +9,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __CRT_LIB_SUPPORT_H__
-#define __CRT_LIB_SUPPORT_H__
+#pragma once
 
 #include <Library/BaseLib.h>
 #include <Library/BaseMemoryLib.h>
@@ -485,4 +484,3 @@ strpbrk (
 #else
 #define UINTPTR_MAX  0xFFFFFFFFUL
 #endif
-#endif

CryptoPkg/Library/Include/stdint.h

@@ -6,8 +6,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef CRYPTO_CRT_STDIO_H_
-#define CRYPTO_CRT_STDIO_H_
+#pragma once
+
 #include <CrtLibSupport.h>
 
 //
@@ -24,5 +24,3 @@ typedef INT64   int64_t;
 typedef UINT64  uint64_t;
 typedef UINTN   uintptr_t;
 #endif
-
-#endif

CryptoPkg/Library/TlsLib/InternalTlsLib.h

@@ -6,8 +6,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __INTERNAL_TLS_LIB_H__
-#define __INTERNAL_TLS_LIB_H__
+#pragma once
 
 #undef _WIN32
 #undef _WIN64
@@ -56,5 +55,3 @@ typedef struct {
   BIO      *BioDebug;
   INT32    Ack;
 } TLS_EXT_CTX;
-
-#endif

CryptoPkg/Library/TlsLibNull/InternalTlsLib.h

@@ -6,11 +6,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __INTERNAL_TLS_LIB_NULL_H__
-#define __INTERNAL_TLS_LIB_NULL_H__
+#pragma once
 
 #include <Library/BaseCryptLib.h>
 #include <Library/DebugLib.h>
 #include <Library/BaseLib.h>
-
-#endif

CryptoPkg/Private/Library/IntrinsicLib.h

@@ -6,11 +6,8 @@
 
 **/
 
-#ifndef INTRINSTIC_LIB_H_
-#define INTRINSTIC_LIB_H_
+#pragma once
 
 //
 // Compiler dependent intrinsic APIs.
 //
-
-#endif

CryptoPkg/Private/Library/MbedTlsLib.h

@@ -6,7 +6,4 @@
 
 **/
 
-#ifndef MBEDTLS_LIB_H_
-#define MBEDTLS_LIB_H_
-
-#endif
+#pragma once

CryptoPkg/Private/Library/OpensslLib.h

@@ -6,9 +6,6 @@
 
 **/
 
-#ifndef OPENSSL_LIB_H_
-#define OPENSSL_LIB_H_
+#pragma once
 
 #include <openssl/opensslv.h>
-
-#endif

CryptoPkg/Private/Ppi/Crypto.h

@@ -6,8 +6,7 @@
 
 **/
 
-#ifndef __EDKII_CRYPTO_PPI_H__
-#define __EDKII_CRYPTO_PPI_H__
+#pragma once
 
 #include <Protocol/Crypto.h>
 
@@ -17,5 +16,3 @@
 typedef EDKII_CRYPTO_PROTOCOL EDKII_CRYPTO_PPI;
 
 extern GUID  gEdkiiCryptoPpiGuid;
-
-#endif

CryptoPkg/Private/Protocol/Crypto.h

@@ -7,8 +7,7 @@
 
 **/
 
-#ifndef __EDKII_CRYPTO_PROTOCOL_H__
-#define __EDKII_CRYPTO_PROTOCOL_H__
+#pragma once
 
 #include <Base.h>
 #include <Library/BaseCryptLib.h>
@@ -5754,5 +5753,3 @@ struct _EDKII_CRYPTO_PROTOCOL {
 };
 
 extern GUID  gEdkiiCryptoProtocolGuid;
-
-#endif

CryptoPkg/Private/Protocol/SmmCrypto.h

@@ -6,8 +6,7 @@
 
 **/
 
-#ifndef __EDKII_SMM_CRYPTO_PROTOCOL_H__
-#define __EDKII_SMM_CRYPTO_PROTOCOL_H__
+#pragma once
 
 #include <Protocol/Crypto.h>
 
@@ -17,5 +16,3 @@
 typedef EDKII_CRYPTO_PROTOCOL EDKII_SMM_CRYPTO_PROTOCOL;
 
 extern GUID  gEdkiiSmmCryptoProtocolGuid;
-
-#endif

CryptoPkg/Test/UnitTest/Library/BaseCryptLib/TestBaseCryptLib.h

@@ -6,8 +6,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
-#ifndef __CRYPTEST_H__
-#define __CRYPTEST_H__
+#pragma once
 
 #include <PiPei.h>
 #include <Uefi.h>
@@ -168,5 +167,3 @@ EFIAPI
 UefiTestMain (
   VOID
   );
-
-#endif