1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
|
/* $Id$ */
/** @file
* IPRT - CRC-32 on top of zlib (very fast).
*/
/*
* Copyright (C) 2009-2022 Oracle and/or its affiliates.
*
* This file is part of VirtualBox base platform packages, as
* available from https://www.virtualbox.org.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, in version 3 of the
* License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses>.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
* in the VirtualBox 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.
*
* SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
*/
/*********************************************************************************************************************************
* Header Files *
*********************************************************************************************************************************/
#include "internal/iprt.h"
#include <iprt/crc.h>
#include <zlib.h>
/** @todo Check if we can't just use the zlib code directly here. */
/**
* Deal with blocks that are too big for the uInt type.
*/
static uint32_t rtCrc32ProcessTooBig(uint32_t uCRC32, const void *pv, size_t cb)
{
const Bytef *pb = (const Bytef *)pv;
do
{
uInt const cbChunk = cb <= ~(uInt)0 ? (uInt)cb : ~(uInt)0;
uCRC32 = crc32(uCRC32, pb, cbChunk);
pb += cbChunk;
cb -= cbChunk;
} while (!cb);
return uCRC32;
}
RTDECL(uint32_t) RTCrc32(const void *pv, size_t cb)
{
uint32_t uCrc = crc32(0, NULL, 0);
if (RT_UNLIKELY((uInt)cb == cb))
uCrc = crc32(uCrc, (const Bytef *)pv, (uInt)cb);
else
uCrc = rtCrc32ProcessTooBig(uCrc, pv, cb);
return uCrc;
}
RT_EXPORT_SYMBOL(RTCrc32);
RTDECL(uint32_t) RTCrc32Start(void)
{
return crc32(0, NULL, 0);
}
RT_EXPORT_SYMBOL(RTCrc32Start);
RTDECL(uint32_t) RTCrc32Process(uint32_t uCRC32, const void *pv, size_t cb)
{
if (RT_UNLIKELY((uInt)cb == cb))
uCRC32 = crc32(uCRC32, (const Bytef *)pv, (uInt)cb);
else
uCRC32 = rtCrc32ProcessTooBig(uCRC32, pv, cb);
return uCRC32;
}
RT_EXPORT_SYMBOL(RTCrc32Process);
RTDECL(uint32_t) RTCrc32Finish(uint32_t uCRC32)
{
return uCRC32;
}
RT_EXPORT_SYMBOL(RTCrc32Finish);
|