xsum.c

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/****************************************************************
Copyright 1990, 1993, 1994, 2000 by AT&T, Lucent Technologies and Bellcore.

Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that the copyright notice and this permission notice and warranty
disclaimer appear in supporting documentation, and that the names of
AT&T, Bell Laboratories, Lucent or Bellcore or any of their entities
not be used in advertising or publicity pertaining to distribution of
the software without specific, written prior permission.

AT&T, Lucent and Bellcore disclaim all warranties with regard to this
software, including all implied warranties of merchantability and
fitness.  In no event shall AT&T or Bellcore be liable for any
special, indirect or consequential damages or any damages whatsoever
resulting from loss of use, data or profits, whether in an action of
contract, negligence or other tortious action, arising out of or in
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****************************************************************/

#undef  _POSIX_SOURCE
#define _POSIX_SOURCE
#include "stdio.h"
#ifndef KR_headers
#include "stdlib.h"
#include "sys/types.h"
#ifndef MSDOS
#include "unistd.h"     /* for read, close */
#endif
#include "fcntl.h"      /* for declaration of open, O_RDONLY */
#endif
#ifdef MSDOS
#include "io.h"
#endif
#ifndef O_RDONLY
#define O_RDONLY 0
#endif
#ifndef O_BINARY
#define O_BINARY O_RDONLY
#endif



 char *progname;
 static int ignore_cr;

 void
#ifdef KR_headers
usage(rc)
#else
usage(int rc)
#endif
{
        fprintf(stderr, "usage: %s [-r] [file [file...]]\n\
        option -r ignores carriage return characters\n", progname);
        exit(rc);
        }

typedef unsigned char Uchar;

 long
#ifdef KR_headers
sum32(sum, x, n)
 register long sum;
 register Uchar *x;
 int n;
#else
sum32(register long sum, register Uchar *x, int n)
#endif
{
        register Uchar *xe;
        static long crc_table[256] = {
                0,              151466134,      302932268,      453595578,
                -9583591,       -160762737,     -312236747,     -463170141,
                -19167182,      -136529756,     -321525474,     -439166584,
                28724267,       145849533,      330837255,      448732561,
                -38334364,      -189783822,     -273059512,     -423738914,
                47895677,       199091435,      282375505,      433292743,
                57448534,       174827712,      291699066,      409324012,
                -67019697,      -184128295,     -300991133,     -418902539,
                -76668728,      -227995554,     -379567644,     -530091662,
                67364049,       218420295,      369985021,      520795499,
                95791354,       213031020,      398182870,      515701056,
                -86479645,      -203465611,     -388624945,     -506380967,
                114897068,      266207290,      349655424,      500195606,
                -105581387,     -256654301,     -340093543,     -490887921,
                -134039394,     -251295736,     -368256590,     -485758684,
                124746887,      241716241,      358686123,      476458301,
                -153337456,     -2395898,       -455991108,     -304803798,
                162629001,      11973919,       465560741,      314102835,
                134728098,      16841012,       436840590,      319723544,
                -144044613,     -26395347,      -446403433,     -329032703,
                191582708,      40657250,       426062040,      274858062,
                -200894995,     -50223749,      -435620671,     -284179369,
                -172959290,     -55056048,      -406931222,     -289830788,
                182263263,      64630089,       416513267,      299125861,
                229794136,      78991822,       532414580,      381366498,
                -220224191,     -69691945,      -523123603,     -371788549,
                -211162774,     -93398532,      -513308602,     -396314416,
                201600371,      84090341,       503991391,      386759881,
                -268078788,     -117292630,     -502591472,     -351526778,
                258520357,      107972019,      493278217,      341959839,
                249493774,      131713432,      483432482,      366454964,
                -239911657,     -122417791,     -474129349,     -356881235,
                -306674912,     -457198666,     -4791796,       -156118374,
                315967289,      466778031,      14362133,       165418627,
                325258002,      442776452,      23947838,       141187752,
                -334573813,     -452329571,     -33509849,      -150495567,
                269456196,      419996626,      33682024,       184992510,
                -278767779,     -429561909,     -43239823,      -194312473,
                -288089226,     -405591072,     -52790694,      -170046772,
                297394031,      415166457,      62373443,       179343061,
                383165416,      533828478,      81314500,       232780370,
                -373594127,     -524527769,     -72022307,      -223201717,
                -401789990,     -519431348,     -100447498,     -217810336,
                392228803,      510123861,      91131631,       208256633,
                -345918580,     -496598246,     -110112096,     -261561802,
                336361365,      487278339,      100800185,      251995695,
                364526526,      482151208,      129260178,      246639108,
                -354943065,     -472854735,     -119955829,     -237064675,
                459588272,      308539942,      157983644,      7181066,
                -469170519,     -317835713,     -167286907,     -16754925,
                -440448382,     -323454444,     -139383890,     -21619912,
                450006683,      332774925,      148697015,      31186721,
                -422325548,     -271261118,     -186797064,     -36011154,
                431888077,      280569435,      196114401,      45565815,
                403200742,      286222960,      168180682,      50400092,
                -412770561,     -295522711,     -177471533,     -59977915,
                -536157576,     -384970002,     -234585260,     -83643454,
                526853729,      375396087,      225003341,      74348507,
                517040714,      399923932,      215944038,      98057200,
                -507728301,     -390357307,     -206385281,     -88735767,
                498987548,      347783818,      263426864,      112501670,
                -489671163,     -338229613,     -253864151,     -103192641,
                -479823314,     -362722632,     -244835582,     -126932076,
                470531639,      353144481,      235265819,      117632909
                };

        xe = x + n;
        while(x < xe)
                sum = crc_table[(sum ^ *x++) & 0xff] ^ (sum >> 8 & 0xffffff);
        return sum;
        }

 int
#ifdef KR_headers
cr_purge(buf, n)
 Uchar *buf;
 int n;
#else
cr_purge(Uchar *buf, int n)
#endif
{
        register Uchar *b, *b1, *be;
        b = buf;
        be = b + n;
        while(b < be)
                if (*b++ == '\r') {
                        b1 = b - 1;
                        while(b < be)
                                if ((*b1 = *b++) != '\r')
                                        b1++;
                        return b1 - buf;
                        }
        return n;
        }

static Uchar Buf[16*1024];

 void
#ifdef KR_headers
process(s, x)
 char *s;
 int x;
#else
process(char *s, int x)
#endif

#if _MSC_VER
#define read _read
#define close _close
#endif

{
        register int n;
        long fsize, sum;

        sum = 0;
        fsize = 0;
        while((n = read(x, (char *)Buf, sizeof(Buf))) > 0) {
                if (ignore_cr)
                        n = cr_purge(Buf, n);
                fsize += n;
                sum = sum32(sum, Buf, n);
                }
        sum &= 0xffffffff;
        if (n==0)
                printf("%s\t%lx\t%ld\n", s, sum & 0xffffffff, fsize);
        else { perror(s); }
        close(x);
        }

#ifdef KR_headers
main(argc, argv)
 char **argv;
#else
main(int argc, char **argv)
#endif
{
        int x;
        char *s;
        static int rc;

        progname = *argv;
        argc = argc;            /* turn off "not used" warning */
        s = *++argv;
        if (s && *s == '-') {
                switch(s[1]) {
                        case '?':
                                usage(0);
                        case 'r':
                                ignore_cr = 1;
                        case '-':
                                break;
                        default:
                                fprintf(stderr, "invalid option %s\n", s);
                                usage(1);
                        }
                s = *++argv;
                }
        if (s) do {
                x = open(s, O_RDONLY|O_BINARY);
                if (x < 0) {
                        fprintf(stderr, "%s: can't open %s\n", progname, s);
                        rc |= 1;
                        }
                else
                        process(s, x);
                }
                while(s = *++argv);
        else {
                process("/dev/stdin", fileno(stdin));
                }
        return rc;
        }

---