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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 14:19:18 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 14:19:18 +0000
commit4035b1bfb1e5843a539a8b624d21952b756974d1 (patch)
treef1e9cd5bf548cbc57ff2fddfb2b4aa9ae95587e2 /src/VBox/Runtime/common/string/memcmp.cpp
parentInitial commit. (diff)
downloadvirtualbox-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.cpp86
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
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--- /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;
+}
+