blob: eb68c0280e2f3a21f49dbbb4f5240777083de4d3 (
plain)
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
|
/* adler32.c
* Compute the Adler32 checksum (RFC 1950)
* 2003 Tomas Kukosa
* Based on code from RFC 1950 (Chapter 9. Appendix: Sample code)
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <string.h>
#include <glib.h>
#include <wsutil/adler32.h>
#define BASE 65521 /* largest prime smaller than 65536 */
/*--- update_adler32 --------------------------------------------------------*/
guint32 update_adler32(guint32 adler, const guint8 *buf, size_t len)
{
guint32 s1 = adler & 0xffff;
guint32 s2 = (adler >> 16) & 0xffff;
size_t n;
for (n = 0; n < len; n++) {
s1 = (s1 + buf[n]) % BASE;
s2 = (s2 + s1) % BASE;
}
return (s2 << 16) + s1;
}
/*--- adler32 ---------------------------------------------------------------*/
guint32 adler32_bytes(const guint8 *buf, size_t len)
{
return update_adler32(1, buf, len);
}
/*--- adler32_str -----------------------------------------------------------*/
guint32 adler32_str(const char *buf)
{
return update_adler32(1, (const guint8*)buf, strlen(buf));
}
/*---------------------------------------------------------------------------*/
/*
* Editor modelines - http://www.wireshark.org/tools/modelines.html
*
* Local Variables:
* c-basic-offset: 2
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=2 tabstop=8 expandtab:
* :indentSize=2:tabSize=8:noTabs=true:
*/
|
