VirtualBox

source: vbox/trunk/src/VBox/Runtime/common/string/memset.cpp@ 62477

Last change on this file since 62477 was 62477, checked in by vboxsync, 8 years ago

(C) 2016

  • Property svn:eol-style set to native
  • Property svn:keywords set to Id Revision
File size: 2.3 KB
Line 
1/* $Id: memset.cpp 62477 2016-07-22 18:27:37Z vboxsync $ */
2/** @file
3 * IPRT - CRT Strings, memset().
4 */
5
6/*
7 * Copyright (C) 2006-2016 Oracle Corporation
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 *
17 * The contents of this file may alternatively be used under the terms
18 * of the Common Development and Distribution License Version 1.0
19 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20 * VirtualBox OSE distribution, in which case the provisions of the
21 * CDDL are applicable instead of those of the GPL.
22 *
23 * You may elect to license modified versions of this file under the
24 * terms and conditions of either the GPL or the CDDL or both.
25 */
26
27
28/*********************************************************************************************************************************
29* Header Files *
30*********************************************************************************************************************************/
31#include <iprt/string.h>
32
33
34/**
35 * Fill a memory block with specific byte.
36 *
37 * @returns pvDst.
38 * @param pvDst Pointer to the block.
39 * @param ch The filler char.
40 * @param cb The size of the block.
41 */
42#ifdef _MSC_VER
43# if _MSC_VER >= 1400
44void * __cdecl memset(__out_bcount_full_opt(_Size) void *pvDst, __in int ch, __in size_t cb)
45# else
46void *memset(void *pvDst, int ch, size_t cb)
47# endif
48#else
49void *memset(void *pvDst, int ch, size_t cb)
50#endif
51{
52 register union
53 {
54 uint8_t *pu8;
55 uint32_t *pu32;
56 void *pvDst;
57 } u;
58 u.pvDst = pvDst;
59
60 /* 32-bit word moves. */
61 register uint32_t u32 = ch | (ch << 8);
62 u32 |= u32 << 16;
63 register size_t c = cb >> 2;
64 while (c-- > 0)
65 *u.pu32++ = u32;
66
67 /* Remaining byte moves. */
68 c = cb & 3;
69 while (c-- > 0)
70 *u.pu8++ = (uint8_t)u32;
71
72 return pvDst;
73}
74
Note: See TracBrowser for help on using the repository browser.

© 2024 Oracle Support Privacy / Do Not Sell My Info Terms of Use Trademark Policy Automated Access Etiquette