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Add global unihash table; use universal hashing instead of CRC.
[mLib] / crc32.c
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1/* -*-c-*-
2 *
3 * $Id: crc32.c,v 1.5 2000/07/21 19:01:33 mdw Exp $
4 *
5 * Calculating cyclic redundancy values (non-cryptographic!)
6 *
7 * (c) 1998 Straylight/Edgeware
8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30/*----- Revision history --------------------------------------------------*
31 *
32 * $Log: crc32.c,v $
33 * Revision 1.5 2000/07/21 19:01:33 mdw
34 * Generate the CRC table rather than hardcoding it.
35 *
36 * Revision 1.4 1999/06/01 09:47:22 mdw
37 * Make the return type of `crc32' a `uint32' now that we have `bits.h'.
38 *
39 * Revision 1.3 1999/05/06 19:51:35 mdw
40 * Reformatted the LGPL notice a little bit.
41 *
42 * Revision 1.2 1999/05/05 18:50:31 mdw
43 * Change licensing conditions to LGPL.
44 *
45 * Revision 1.1.1.1 1998/06/17 23:44:42 mdw
46 * Initial version of mLib
47 *
48 */
49
50/*----- Header files ------------------------------------------------------*/
51
52/* --- ANSI headers --- */
53
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57
58/* --- Local headers --- */
59
60#include "bits.h"
61#include "crc32.h"
62
63/*----- Functionc provided ------------------------------------------------*/
64
65/* --- @crc32@ --- *
66 *
67 * Arguments: @uint32 crc@ = carryover from previous call, or zero
68 * @const void *buf@ = pointer to buffer to check
69 * @size_t sz@ = size of the buffer
70 *
71 * Returns: The CRC updated by the new buffer.
72 *
73 * Use: A restartable CRC calculator. This is just a function
74 * wrapper for the macro version.
75 */
76
77uint32 crc32(uint32 crc, const void *buf, size_t sz)
78{
79 uint32 c;
80 CRC32(c, crc, buf, sz);
81 return (c);
82}
83
84/*----- Test driver -------------------------------------------------------*/
85
86#ifdef TEST_RIG
87
88#include <stdio.h>
89
90int main(void)
91{
92 uint32 crc = 0;
93 char buf[BUFSIZ];
94 int r;
95
96 do {
97 r = fread(buf, 1, sizeof(buf), stdin);
98 if (r > 0)
99 crc = crc32(crc, buf, r);
100 } while (r == sizeof(buf));
101
102 printf("crc32(stdin) = %08lx\n", (unsigned long)crc);
103 return (0);
104}
105
106#endif
107
108/*----- That's all, folks -------------------------------------------------*/