diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 14:19:18 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 14:19:18 +0000 |
commit | 4035b1bfb1e5843a539a8b624d21952b756974d1 (patch) | |
tree | f1e9cd5bf548cbc57ff2fddfb2b4aa9ae95587e2 /src/VBox/Runtime/common/string/memcmp.cpp | |
parent | Initial commit. (diff) | |
download | virtualbox-4035b1bfb1e5843a539a8b624d21952b756974d1.tar.xz virtualbox-4035b1bfb1e5843a539a8b624d21952b756974d1.zip |
Adding upstream version 6.1.22-dfsg.upstream/6.1.22-dfsgupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/Runtime/common/string/memcmp.cpp')
-rw-r--r-- | src/VBox/Runtime/common/string/memcmp.cpp | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/src/VBox/Runtime/common/string/memcmp.cpp b/src/VBox/Runtime/common/string/memcmp.cpp new file mode 100644 index 00000000..de7c3a27 --- /dev/null +++ b/src/VBox/Runtime/common/string/memcmp.cpp @@ -0,0 +1,86 @@ +/* $Id: memcmp.cpp $ */ +/** @file + * IPRT - CRT Strings, memcmp(). + */ + +/* + * Copyright (C) 2006-2020 Oracle Corporation + * + * This file is part of VirtualBox Open Source Edition (OSE), as + * available from http://www.virtualbox.org. This file is free software; + * you can redistribute it and/or modify it under the terms of the GNU + * General Public License (GPL) as published by the Free Software + * Foundation, in version 2 as it comes in the "COPYING" file of the + * VirtualBox OSE distribution. VirtualBox OSE is distributed in the + * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. + * + * The contents of this file may alternatively be used under the terms + * of the Common Development and Distribution License Version 1.0 + * (CDDL) only, as it comes in the "COPYING.CDDL" file of the + * VirtualBox OSE distribution, in which case the provisions of the + * CDDL are applicable instead of those of the GPL. + * + * You may elect to license modified versions of this file under the + * terms and conditions of either the GPL or the CDDL or both. + */ + + +/********************************************************************************************************************************* +* Header Files * +*********************************************************************************************************************************/ +#include <iprt/string.h> +#include <iprt/types.h> + + +/** + * Copies a memory. + * + * @returns 0 if pvDst and pvSrc are equal + * @returns <0 if pvDst is 'smaller' than pvSrc. + * @returns >0 if pvDst is 'larger' than pvSrc. + * + * @param pvDst Pointer to the target block. + * @param pvSrc Pointer to the source block. + * @param cb The size of the block. + */ +#ifdef _MSC_VER +# if _MSC_VER >= 1400 +__checkReturn int __cdecl memcmp(__in_bcount_opt(_Size) const void * pvDst, __in_bcount_opt(_Size) const void * pvSrc, __in size_t cb) +# else +int __cdecl memcmp(const void *pvDst, const void *pvSrc, size_t cb) +# endif +#else +int memcmp(const void *pvDst, const void *pvSrc, size_t cb) +#endif +{ + register union + { + uint8_t const *pu8; + uint32_t const *pu32; + void const *pv; + } uDst, uSrc; + uDst.pv = pvDst; + uSrc.pv = pvSrc; + + /* 32-bit word compare. */ + register size_t c = cb >> 2; + while (c-- > 0) + { + /* ASSUMES int is at least 32-bit! */ + register int32_t iDiff = *uDst.pu32++ - *uSrc.pu32++; + if (iDiff) + return iDiff; + } + + /* Remaining byte moves. */ + c = cb & 3; + while (c-- > 0) + { + register int8_t iDiff = *uDst.pu8++ - *uSrc.pu8++; + if (iDiff) + return iDiff; + } + + return 0; +} + |