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crc.c revision 1.14
      1  1.14  kleink /*	$NetBSD: crc.c,v 1.14 2003/12/20 23:41:38 kleink Exp $	*/
      2   1.5   glass 
      3   1.1     cgd /*-
      4   1.3     cgd  * Copyright (c) 1991, 1993
      5   1.3     cgd  *	The Regents of the University of California.  All rights reserved.
      6   1.1     cgd  *
      7   1.1     cgd  * This code is derived from software contributed to Berkeley by
      8   1.3     cgd  * James W. Williams of NASA Goddard Space Flight Center.
      9   1.1     cgd  *
     10   1.1     cgd  * Redistribution and use in source and binary forms, with or without
     11   1.1     cgd  * modification, are permitted provided that the following conditions
     12   1.1     cgd  * are met:
     13   1.1     cgd  * 1. Redistributions of source code must retain the above copyright
     14   1.1     cgd  *    notice, this list of conditions and the following disclaimer.
     15   1.1     cgd  * 2. Redistributions in binary form must reproduce the above copyright
     16   1.1     cgd  *    notice, this list of conditions and the following disclaimer in the
     17   1.1     cgd  *    documentation and/or other materials provided with the distribution.
     18  1.13     agc  * 3. Neither the name of the University nor the names of its contributors
     19   1.1     cgd  *    may be used to endorse or promote products derived from this software
     20   1.1     cgd  *    without specific prior written permission.
     21   1.1     cgd  *
     22   1.1     cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     23   1.1     cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24   1.1     cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25   1.1     cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     26   1.1     cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     27   1.1     cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     28   1.1     cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     29   1.1     cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     30   1.1     cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     31   1.1     cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     32   1.1     cgd  * SUCH DAMAGE.
     33   1.1     cgd  */
     34   1.1     cgd 
     35   1.8   lukem #include <sys/cdefs.h>
     36  1.12   bjh21 #if defined(__RCSID) && !defined(lint)
     37   1.5   glass #if 0
     38   1.5   glass static char sccsid[] = "@(#)crc.c	8.1 (Berkeley) 6/17/93";
     39   1.5   glass #else
     40  1.14  kleink __RCSID("$NetBSD: crc.c,v 1.14 2003/12/20 23:41:38 kleink Exp $");
     41   1.5   glass #endif
     42   1.1     cgd #endif /* not lint */
     43   1.1     cgd 
     44   1.1     cgd #include <sys/types.h>
     45   1.1     cgd #include <unistd.h>
     46   1.6     cgd 
     47   1.6     cgd #include "extern.h"
     48   1.1     cgd 
     49   1.7     jtc static const u_int32_t crctab[] = {
     50   1.3     cgd 	0x0,
     51   1.3     cgd 	0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b,
     52   1.3     cgd 	0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6,
     53   1.3     cgd 	0x2b4bcb61, 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
     54   1.3     cgd 	0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9, 0x5f15adac,
     55   1.3     cgd 	0x5bd4b01b, 0x569796c2, 0x52568b75, 0x6a1936c8, 0x6ed82b7f,
     56   1.3     cgd 	0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3, 0x709f7b7a,
     57   1.3     cgd 	0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
     58   1.3     cgd 	0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58,
     59   1.3     cgd 	0xbaea46ef, 0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033,
     60   1.3     cgd 	0xa4ad16ea, 0xa06c0b5d, 0xd4326d90, 0xd0f37027, 0xddb056fe,
     61   1.3     cgd 	0xd9714b49, 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
     62   1.3     cgd 	0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, 0xe13ef6f4,
     63   1.3     cgd 	0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0,
     64   1.3     cgd 	0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5,
     65   1.3     cgd 	0x2ac12072, 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
     66   1.3     cgd 	0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca, 0x7897ab07,
     67   1.3     cgd 	0x7c56b6b0, 0x71159069, 0x75d48dde, 0x6b93dddb, 0x6f52c06c,
     68   1.3     cgd 	0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1,
     69   1.3     cgd 	0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
     70   1.3     cgd 	0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b,
     71   1.3     cgd 	0xbb60adfc, 0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698,
     72   1.3     cgd 	0x832f1041, 0x87ee0df6, 0x99a95df3, 0x9d684044, 0x902b669d,
     73   1.3     cgd 	0x94ea7b2a, 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
     74   1.3     cgd 	0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, 0xc6bcf05f,
     75   1.3     cgd 	0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34,
     76   1.3     cgd 	0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80,
     77   1.3     cgd 	0x644fc637, 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
     78   1.3     cgd 	0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f, 0x5c007b8a,
     79   1.3     cgd 	0x58c1663d, 0x558240e4, 0x51435d53, 0x251d3b9e, 0x21dc2629,
     80   1.3     cgd 	0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5, 0x3f9b762c,
     81   1.3     cgd 	0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
     82   1.3     cgd 	0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e,
     83   1.3     cgd 	0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65,
     84   1.3     cgd 	0xeba91bbc, 0xef68060b, 0xd727bbb6, 0xd3e6a601, 0xdea580d8,
     85   1.3     cgd 	0xda649d6f, 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
     86   1.3     cgd 	0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, 0xae3afba2,
     87   1.3     cgd 	0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71,
     88   1.3     cgd 	0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74,
     89   1.3     cgd 	0x857130c3, 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
     90   1.3     cgd 	0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, 0x7b827d21,
     91   1.3     cgd 	0x7f436096, 0x7200464f, 0x76c15bf8, 0x68860bfd, 0x6c47164a,
     92   1.3     cgd 	0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e, 0x18197087,
     93   1.3     cgd 	0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
     94   1.3     cgd 	0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d,
     95   1.3     cgd 	0x2056cd3a, 0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce,
     96   1.3     cgd 	0xcc2b1d17, 0xc8ea00a0, 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb,
     97   1.3     cgd 	0xdbee767c, 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
     98   1.3     cgd 	0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, 0x89b8fd09,
     99   1.3     cgd 	0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662,
    100   1.3     cgd 	0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf,
    101   1.3     cgd 	0xa2f33668, 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
    102   1.1     cgd };
    103   1.1     cgd 
    104   1.1     cgd /*
    105   1.3     cgd  * Compute a POSIX 1003.2 checksum.  This routine has been broken out so that
    106   1.3     cgd  * other programs can use it.  It takes a file descriptor to read from and
    107   1.3     cgd  * locations to store the crc and the number of bytes read.  It returns 0 on
    108   1.3     cgd  * success and 1 on failure.  Errno is set on failure.
    109   1.1     cgd  */
    110   1.3     cgd int
    111  1.10  atatat crc(fd, cval, clen)
    112   1.1     cgd 	register int fd;
    113  1.14  kleink 	u_int32_t *cval;
    114  1.14  kleink 	off_t *clen;
    115   1.1     cgd {
    116   1.1     cgd 	register u_char *p;
    117   1.3     cgd 	register int nr;
    118  1.14  kleink 	register u_int32_t thecrc;
    119  1.14  kleink 	off_t len;
    120   1.3     cgd 	u_char buf[16 * 1024];
    121   1.3     cgd 
    122   1.3     cgd #define	COMPUTE(var, ch)	(var) = (var) << 8 ^ crctab[(var) >> 24 ^ (ch)]
    123   1.1     cgd 
    124  1.14  kleink 	thecrc = 0;
    125  1.14  kleink 	len = 0;
    126   1.1     cgd 	while ((nr = read(fd, buf, sizeof(buf))) > 0)
    127   1.3     cgd 		for (len += nr, p = buf; nr--; ++p) {
    128  1.10  atatat 			COMPUTE(thecrc, *p);
    129   1.1     cgd 		}
    130   1.1     cgd 	if (nr < 0)
    131   1.3     cgd 		return (1);
    132   1.3     cgd 
    133   1.3     cgd 	*clen = len;
    134   1.1     cgd 
    135   1.3     cgd 	/* Include the length of the file. */
    136   1.3     cgd 	for (; len != 0; len >>= 8) {
    137  1.10  atatat 		COMPUTE(thecrc, len & 0xff);
    138   1.3     cgd 	}
    139   1.3     cgd 
    140  1.10  atatat 	*cval = ~thecrc;
    141   1.3     cgd 	return (0);
    142   1.1     cgd }
    143