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/* cksum -- calculate and print POSIX.2 checksums and sizes of files
Copyright (C) 92, 1995-1999 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by Q. Frank Xia, qx@math.columbia.edu.
Cosmetic changes and reorganization by David MacKenzie, djm@gnu.ai.mit.edu.
Usage: cksum [file...]
The code segment between "#ifdef CRCTAB" and "#else" is the code
which calculates the "crctab". It is included for those who want
verify the correctness of the "crctab". To recreate the "crctab",
do following:
cc -DCRCTAB -o crctab cksum.c
crctab > crctab.h
As Bruce Evans pointed out to me, the crctab in the sample C code
in 4.9.10 Rationale of P1003.2/D11.2 is represented in reversed order.
Namely, 0x01 is represented as 0x80, 0x02 is represented as 0x40, etc.
The generating polynomial is crctab[0x80]=0xedb88320 instead of
crctab[1]=0x04C11DB7. But the code works only for a non-reverse order
crctab. Therefore, the sample implementation is wrong.
This software is compatible with neither the System V nor the BSD
`sum' program. It is supposed to conform to P1003.2/D11.2,
except foreign language interface (4.9.5.3 of P1003.2/D11.2) support.
Any inconsistency with the standard except 4.9.5.3 is a bug. */
#include <config.h>
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "cksum"
#define AUTHORS "Q. Frank Xia"
#ifdef CRCTAB
# include <stdio.h>
# define BIT(x) ( (unsigned long)1 << (x) )
# define SBIT BIT(31)
/* The generating polynomial is
32 26 23 22 16 12 11 10 8 7 5 4 2 1
G(X)=X + X + X + X + X + X + X + X + X + X + X + X + X + X + 1
The i bit in GEN is set if X^i is a summand of G(X) except X^32. */
# define GEN (BIT(26)|BIT(23)|BIT(22)|BIT(16)|BIT(12)|BIT(11)|BIT(10)\
|BIT(8) |BIT(7) |BIT(5) |BIT(4) |BIT(2) |BIT(1) |BIT(0));
static unsigned long r[8];
static void
fill_r ()
{
int i;
r[0] = GEN;
for (i = 1; i < 8; i++)
r[i] = (r[i - 1] & SBIT) ? (r[i - 1] << 1) ^ r[0] : r[i - 1] << 1;
}
static unsigned long
remainder (m)
int m;
{
unsigned long rem = 0;
int i;
for (i = 0; i < 8; i++)
if (BIT (i) & m)
rem = rem ^ r[i];
return rem & 0xFFFFFFFF; /* Make it run on 64-bit machine. */
}
int
main ()
{
int i;
fill_r ();
printf ("unsigned long crctab[256] = {\n 0x0");
for (i = 0; i < 51; i++)
{
printf (",\n 0x%08X, 0x%08X, 0x%08X, 0x%08X, 0x%08X",
remainder (i * 5 + 1), remainder (i * 5 + 2), remainder (i * 5 + 3),
remainder (i * 5 + 4), remainder (i * 5 + 5));
}
printf ("\n};\n");
exit (EXIT_SUCCESS);
}
#else /* !CRCTAB */
# include <stdio.h>
# include <getopt.h>
# include <sys/types.h>
# include "system.h"
# include "long-options.h"
# include "error.h"
/* Number of bytes to read at once. */
# define BUFLEN (1 << 16)
/* The name this program was run with. */
char *program_name;
static struct option const long_options[] =
{
{0, 0, 0, 0}
};
static unsigned long const crctab[256] =
{
0x0,
0x04C11DB7, 0x09823B6E, 0x0D4326D9, 0x130476DC, 0x17C56B6B,
0x1A864DB2, 0x1E475005, 0x2608EDB8, 0x22C9F00F, 0x2F8AD6D6,
0x2B4BCB61, 0x350C9B64, 0x31CD86D3, 0x3C8EA00A, 0x384FBDBD,
0x4C11DB70, 0x48D0C6C7, 0x4593E01E, 0x4152FDA9, 0x5F15ADAC,
0x5BD4B01B, 0x569796C2, 0x52568B75, 0x6A1936C8, 0x6ED82B7F,
0x639B0DA6, 0x675A1011, 0x791D4014, 0x7DDC5DA3, 0x709F7B7A,
0x745E66CD, 0x9823B6E0, 0x9CE2AB57, 0x91A18D8E, 0x95609039,
0x8B27C03C, 0x8FE6DD8B, 0x82A5FB52, 0x8664E6E5, 0xBE2B5B58,
0xBAEA46EF, 0xB7A96036, 0xB3687D81, 0xAD2F2D84, 0xA9EE3033,
0xA4AD16EA, 0xA06C0B5D, 0xD4326D90, 0xD0F37027, 0xDDB056FE,
0xD9714B49, 0xC7361B4C, 0xC3F706FB, 0xCEB42022, 0xCA753D95,
0xF23A8028, 0xF6FB9D9F, 0xFBB8BB46, 0xFF79A6F1, 0xE13EF6F4,
0xE5FFEB43, 0xE8BCCD9A, 0xEC7DD02D, 0x34867077, 0x30476DC0,
0x3D044B19, 0x39C556AE, 0x278206AB, 0x23431B1C, 0x2E003DC5,
0x2AC12072, 0x128E9DCF, 0x164F8078, 0x1B0CA6A1, 0x1FCDBB16,
0x018AEB13, 0x054BF6A4, 0x0808D07D, 0x0CC9CDCA, 0x7897AB07,
0x7C56B6B0, 0x71159069, 0x75D48DDE, 0x6B93DDDB, 0x6F52C06C,
0x6211E6B5, 0x66D0FB02, 0x5E9F46BF, 0x5A5E5B08, 0x571D7DD1,
0x53DC6066, 0x4D9B3063, 0x495A2DD4, 0x44190B0D, 0x40D816BA,
0xACA5C697, 0xA864DB20, 0xA527FDF9, 0xA1E6E04E, 0xBFA1B04B,
0xBB60ADFC, 0xB6238B25, 0xB2E29692, 0x8AAD2B2F, 0x8E6C3698,
0x832F1041, 0x87EE0DF6, 0x99A95DF3, 0x9D684044, 0x902B669D,
0x94EA7B2A, 0xE0B41DE7, 0xE4750050, 0xE9362689, 0xEDF73B3E,
0xF3B06B3B, 0xF771768C, 0xFA325055, 0xFEF34DE2, 0xC6BCF05F,
0xC27DEDE8, 0xCF3ECB31, 0xCBFFD686, 0xD5B88683, 0xD1799B34,
0xDC3ABDED, 0xD8FBA05A, 0x690CE0EE, 0x6DCDFD59, 0x608EDB80,
0x644FC637, 0x7A089632, 0x7EC98B85, 0x738AAD5C, 0x774BB0EB,
0x4F040D56, 0x4BC510E1, 0x46863638, 0x42472B8F, 0x5C007B8A,
0x58C1663D, 0x558240E4, 0x51435D53, 0x251D3B9E, 0x21DC2629,
0x2C9F00F0, 0x285E1D47, 0x36194D42, 0x32D850F5, 0x3F9B762C,
0x3B5A6B9B, 0x0315D626, 0x07D4CB91, 0x0A97ED48, 0x0E56F0FF,
0x1011A0FA, 0x14D0BD4D, 0x19939B94, 0x1D528623, 0xF12F560E,
0xF5EE4BB9, 0xF8AD6D60, 0xFC6C70D7, 0xE22B20D2, 0xE6EA3D65,
0xEBA91BBC, 0xEF68060B, 0xD727BBB6, 0xD3E6A601, 0xDEA580D8,
0xDA649D6F, 0xC423CD6A, 0xC0E2D0DD, 0xCDA1F604, 0xC960EBB3,
0xBD3E8D7E, 0xB9FF90C9, 0xB4BCB610, 0xB07DABA7, 0xAE3AFBA2,
0xAAFBE615, 0xA7B8C0CC, 0xA379DD7B, 0x9B3660C6, 0x9FF77D71,
0x92B45BA8, 0x9675461F, 0x8832161A, 0x8CF30BAD, 0x81B02D74,
0x857130C3, 0x5D8A9099, 0x594B8D2E, 0x5408ABF7, 0x50C9B640,
0x4E8EE645, 0x4A4FFBF2, 0x470CDD2B, 0x43CDC09C, 0x7B827D21,
0x7F436096, 0x7200464F, 0x76C15BF8, 0x68860BFD, 0x6C47164A,
0x61043093, 0x65C52D24, 0x119B4BE9, 0x155A565E, 0x18197087,
0x1CD86D30, 0x029F3D35, 0x065E2082, 0x0B1D065B, 0x0FDC1BEC,
0x3793A651, 0x3352BBE6, 0x3E119D3F, 0x3AD08088, 0x2497D08D,
0x2056CD3A, 0x2D15EBE3, 0x29D4F654, 0xC5A92679, 0xC1683BCE,
0xCC2B1D17, 0xC8EA00A0, 0xD6AD50A5, 0xD26C4D12, 0xDF2F6BCB,
0xDBEE767C, 0xE3A1CBC1, 0xE760D676, 0xEA23F0AF, 0xEEE2ED18,
0xF0A5BD1D, 0xF464A0AA, 0xF9278673, 0xFDE69BC4, 0x89B8FD09,
0x8D79E0BE, 0x803AC667, 0x84FBDBD0, 0x9ABC8BD5, 0x9E7D9662,
0x933EB0BB, 0x97FFAD0C, 0xAFB010B1, 0xAB710D06, 0xA6322BDF,
0xA2F33668, 0xBCB4666D, 0xB8757BDA, 0xB5365D03, 0xB1F740B4
};
/* Nonzero if any of the files read were the standard input. */
static int have_read_stdin;
/* Calculate and print the checksum and length in bytes
of file FILE, or of the standard input if FILE is "-".
If PRINT_NAME is nonzero, print FILE next to the checksum and size.
Return 0 if successful, -1 if an error occurs. */
static int
cksum (char *file, int print_name)
{
unsigned char buf[BUFLEN];
unsigned long crc = 0;
long length = 0;
long bytes_read;
register FILE *fp;
if (STREQ (file, "-"))
{
fp = stdin;
have_read_stdin = 1;
}
else
{
fp = fopen (file, "r");
if (fp == NULL)
{
error (0, errno, "%s", file);
return -1;
}
}
/* Read input in BINARY mode, unless it is a console device. */
SET_BINARY (fileno (fp));
while ((bytes_read = fread (buf, 1, BUFLEN, fp)) > 0)
{
unsigned char *cp = buf;
length += bytes_read;
while (bytes_read--)
crc = (crc << 8) ^ crctab[((crc >> 24) ^ *(cp++)) & 0xFF];
}
if (ferror (fp))
{
error (0, errno, "%s", file);
if (!STREQ (file, "-"))
fclose (fp);
return -1;
}
if (!STREQ (file, "-") && fclose (fp) == EOF)
{
error (0, errno, "%s", file);
return -1;
}
bytes_read = length;
while (bytes_read > 0)
{
crc = (crc << 8) ^ crctab[((crc >> 24) ^ bytes_read) & 0xFF];
bytes_read >>= 8;
}
crc = ~crc & 0xFFFFFFFF;
printf ("%lu %ld", crc, length);
if (print_name)
printf (" %s", file);
putchar ('\n');
return 0;
}
void
usage (int status)
{
if (status != 0)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("\
Usage: %s [OPTION]... [FILE]...\n\
"),
program_name);
printf (_("\
Print CRC checksum and byte counts of each FILE.\n\
\n\
--help display this help and exit\n\
--version output version information and exit\n\
"));
puts (_("\nReport bugs to <bug-textutils@gnu.org>."));
}
exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
}
int
main (int argc, char **argv)
{
int i, c;
int errors = 0;
program_name = argv[0];
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
parse_long_options (argc, argv, PROGRAM_NAME, GNU_PACKAGE, VERSION,
"Q. Frank Xia", usage);
have_read_stdin = 0;
while ((c = getopt_long (argc, argv, "", long_options, NULL)) != -1)
{
switch (c)
{
case 0:
break;
default:
usage (1);
}
}
if (optind >= argc)
{
if (cksum ("-", 0) < 0)
errors = 1;
}
else
{
for (i = optind; i < argc; i++)
if (cksum (argv[i], 1) < 0)
errors = 1;
}
if (have_read_stdin && fclose (stdin) == EOF)
error (EXIT_FAILURE, errno, "-");
exit (errors == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
}
#endif /* !CRCTAB */
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