Commit 563da075 authored by Simon Josefsson's avatar Simon Josefsson

Add crc module.

parent 15ca72eb
2005-10-11 Simon Josefsson <jas@extundo.com>
* tests/test-crc.c: New file.
* modules/crc, modules/crc-tests: New files.
2005-10-10 Paul Eggert <eggert@cs.ucla.edu>
* modules/mempcpy (License): GPL -> LGPL.
......
2005-10-11 Simon Josefsson <jas@extundo.com>
* crc.h, crc.c: New files.
* gc.h (gc_hash_buffer): Add doc.
2005-10-11 Bruno Haible <bruno@clisp.org>
......
/* crc.c -- cyclic redundancy checks
Copyright (C) 2005 Free Software Foundation, Inc.
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; either version 2, or (at
your option) any later version.
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, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA. */
/* Written by Simon Josefsson. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "crc.h"
/* Table of CRCs of all 8-bit messages. Generated by running code
from RFC 1952 modified to print out the table. */
static const uint32_t crc32_table[256] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
/*
* The following function was extracted from RFC 1952 by Simon
* Josefsson. It was modified to avoid initial and final XOR, to use
* size_t for the buffer length, and to use the const keyword.
*/
uint32_t
crc32_update_no_xor (uint32_t crc, const char *buf, size_t len)
{
size_t n;
for (n = 0; n < len; n++)
crc = crc32_table[(crc ^ buf[n]) & 0xff] ^ (crc >> 8);
return crc;
}
uint32_t
crc32_no_xor (const char *buf, size_t len)
{
return crc32_update_no_xor (0L, buf, len);
}
uint32_t
crc32_update (uint32_t crc, const char *buf, size_t len)
{
return crc32_update_no_xor (0L ^ 0xffffffffL, buf, len) ^ 0xffffffffL;
}
uint32_t
crc32 (const char *buf, size_t len)
{
return crc32_update (0L, buf, len);
}
/* crc.h -- cyclic redundancy checks
Copyright (C) 2005 Free Software Foundation, Inc.
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; either version 2, or (at your option)
any later version.
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, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Simon Josefsson. */
#ifndef CRC_H
# define CRC_H 1
#include <stddef.h>
#if HAVE_INTTYPES_H
# include <inttypes.h>
#endif
#if HAVE_STDINT_H
# include <stdint.h>
#endif
/* Compute CRC-32 value of LEN bytes long BUF, and return it. */
extern uint32_t crc32 (const char *buf, size_t len);
/* Incrementally update CRC-32 value CRC using LEN bytes long BUF. In
the first call, use 0 as the value for CRC. Return the updated
CRC-32 value. */
extern uint32_t crc32_update (uint32_t crc, const char *buf, size_t len);
/* Compute modified-CRC-32 value of LEN bytes long BUF, and return it.
The "modification" is to avoid the initial and final XOR operation.
Due to historic implementation errors, this variant is sometimes
used (i.e., in RFC 3961). */
extern uint32_t crc32_no_xor (const char *buf, size_t len);
/* Incrementally update modified-CRC-32 value CRC using LEN bytes long
BUF. In the first call, use 0 as the value for CRC. Return the
updated modified-CRC-32 value. The "modification" is to avoid the
initial and final XOR operation. Due to historic implementation
errors, this variant is sometimes used (i.e., in RFC 3961). */
extern uint32_t
crc32_update_no_xor (uint32_t crc, const char *buf, size_t len);
#endif /* CRC_H */
2005-10-11 Simon Josefsson <jas@extundo.com>
* crc.m4: New file.
2005-10-07 Simon Josefsson <jas@extundo.com>
* memxor.m4: Remove gl_C_RESTRICT call.
......
# crc.m4 serial 1
dnl Copyright (C) 2005 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
AC_DEFUN([gl_CRC],
[
AC_LIBSOURCES([crc.h, crc.c])
AC_LIBOBJ([crc])
])
Description:
Compute cyclic redundancy codes.
Files:
lib/crc.h
lib/crc.c
m4/crc.m4
Depends-on:
stdint
configure.ac:
gl_CRC
Makefile.am:
Include:
"crc.h"
License:
LGPL
Maintainer:
Simon Josefsson
Files:
tests/test-crc.c
Depends-on:
configure.ac:
Makefile.am:
TESTS += test-crc
noinst_PROGRAMS += test-crc
test_crc_SOURCES = test-crc.c
/*
* Copyright (C) 2005 Free Software Foundation
*
* 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; either version 2, or (at your option)
* any later version.
*
* 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, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA. */
/* Written by Simon Josefsson. */
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include "crc.h"
#include <stdio.h>
int
main (int argc, char *argv[])
{
uint32_t p;
p = crc32_update_no_xor (42, "foo", 3);
if (p != 0x46e87f05)
{
printf ("cunx got %lx\n", p);
return 1;
}
p = crc32_no_xor ("foo", 3);
if (p != 0x7332bc33)
{
printf ("cnx got %lx\n", p);
return 1;
}
p = crc32_update (42, "foo", 3);
if (p != 0x8c736521)
{
printf ("cu got %lx\n", p);
return 1;
}
p = crc32 ("foo", 3);
if (p != 0x8c736521)
{
printf ("c got %lx\n", p);
return 1;
}
return 0;
}
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