mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-16 10:20:30 +00:00
ad64363769
Remove __STDC__ (which means we now use stdarg rather than vararg) Remove register Remove main prototype
212 lines
5.5 KiB
C
212 lines
5.5 KiB
C
/*
|
|
* Copyright (c) 1989, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Landon Curt Noll.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. All advertising materials mentioning features or use of this software
|
|
* must display the following acknowledgement:
|
|
* This product includes software developed by the University of
|
|
* California, Berkeley and its contributors.
|
|
* 4. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#ifndef lint
|
|
static const char copyright[] =
|
|
"@(#) Copyright (c) 1989, 1993\n\
|
|
The Regents of the University of California. All rights reserved.\n";
|
|
#endif /* not lint */
|
|
|
|
#ifndef lint
|
|
#if 0
|
|
static char sccsid[] = "@(#)factor.c 8.4 (Berkeley) 5/4/95";
|
|
#endif
|
|
static const char rcsid[] =
|
|
"$FreeBSD$";
|
|
#endif /* not lint */
|
|
|
|
/*
|
|
* factor - factor a number into primes
|
|
*
|
|
* By: Landon Curt Noll chongo@toad.com, ...!{sun,tolsoft}!hoptoad!chongo
|
|
*
|
|
* chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\
|
|
*
|
|
* usage:
|
|
* factor [number] ...
|
|
*
|
|
* The form of the output is:
|
|
*
|
|
* number: factor1 factor1 factor2 factor3 factor3 factor3 ...
|
|
*
|
|
* where factor1 < factor2 < factor3 < ...
|
|
*
|
|
* If no args are given, the list of numbers are read from stdin.
|
|
*/
|
|
|
|
#include <err.h>
|
|
#include <ctype.h>
|
|
#include <errno.h>
|
|
#include <limits.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#include "primes.h"
|
|
|
|
/*
|
|
* prime[i] is the (i-1)th prime.
|
|
*
|
|
* We are able to sieve 2^32-1 because this byte table yields all primes
|
|
* up to 65537 and 65537^2 > 2^32-1.
|
|
*/
|
|
extern ubig prime[];
|
|
extern ubig *pr_limit; /* largest prime in the prime array */
|
|
|
|
int hflag;
|
|
|
|
void pr_fact(ubig); /* print factors of a value */
|
|
void usage(void);
|
|
|
|
int
|
|
main(argc, argv)
|
|
int argc;
|
|
char *argv[];
|
|
{
|
|
ubig val;
|
|
int ch;
|
|
char *p, buf[100]; /* > max number of digits. */
|
|
|
|
while ((ch = getopt(argc, argv, "h")) != -1)
|
|
switch (ch) {
|
|
case 'h':
|
|
hflag++;
|
|
break;
|
|
case '?':
|
|
default:
|
|
usage();
|
|
}
|
|
argc -= optind;
|
|
argv += optind;
|
|
|
|
/* No args supplied, read numbers from stdin. */
|
|
if (argc == 0)
|
|
for (;;) {
|
|
if (fgets(buf, sizeof(buf), stdin) == NULL) {
|
|
if (ferror(stdin))
|
|
err(1, "stdin");
|
|
exit (0);
|
|
}
|
|
for (p = buf; isblank(*p); ++p);
|
|
if (*p == '\n' || *p == '\0')
|
|
continue;
|
|
if (*p == '-')
|
|
errx(1, "negative numbers aren't permitted.");
|
|
errno = 0;
|
|
val = strtoul(buf, &p, 0);
|
|
if (errno)
|
|
err(1, "%s", buf);
|
|
if (*p != '\n')
|
|
errx(1, "%s: illegal numeric format.", buf);
|
|
pr_fact(val);
|
|
}
|
|
/* Factor the arguments. */
|
|
else
|
|
for (; *argv != NULL; ++argv) {
|
|
if (argv[0][0] == '-')
|
|
errx(1, "negative numbers aren't permitted.");
|
|
errno = 0;
|
|
val = strtoul(argv[0], &p, 0);
|
|
if (errno)
|
|
err(1, "%s", argv[0]);
|
|
if (*p != '\0')
|
|
errx(1, "%s: illegal numeric format.", argv[0]);
|
|
pr_fact(val);
|
|
}
|
|
exit(0);
|
|
}
|
|
|
|
/*
|
|
* pr_fact - print the factors of a number
|
|
*
|
|
* If the number is 0 or 1, then print the number and return.
|
|
* If the number is < 0, print -1, negate the number and continue
|
|
* processing.
|
|
*
|
|
* Print the factors of the number, from the lowest to the highest.
|
|
* A factor will be printed multiple times if it divides the value
|
|
* multiple times.
|
|
*
|
|
* Factors are printed with leading tabs.
|
|
*/
|
|
void
|
|
pr_fact(val)
|
|
ubig val; /* Factor this value. */
|
|
{
|
|
ubig *fact; /* The factor found. */
|
|
|
|
/* Firewall - catch 0 and 1. */
|
|
if (val == 0) /* Historical practice; 0 just exits. */
|
|
exit(0);
|
|
if (val == 1) {
|
|
(void)printf("1: 1\n");
|
|
return;
|
|
}
|
|
|
|
/* Factor value. */
|
|
(void)printf(hflag ? "0x%lx:" : "%lu:", val);
|
|
for (fact = &prime[0]; val > 1; ++fact) {
|
|
/* Look for the smallest factor. */
|
|
do {
|
|
if (val % (long)*fact == 0)
|
|
break;
|
|
} while (++fact <= pr_limit);
|
|
|
|
/* Watch for primes larger than the table. */
|
|
if (fact > pr_limit) {
|
|
(void)printf(hflag ? " 0x%lx" : " %lu", val);
|
|
break;
|
|
}
|
|
|
|
/* Divide factor out until none are left. */
|
|
do {
|
|
(void)printf(hflag ? " 0x%lx" : " %lu", *fact);
|
|
val /= *fact;
|
|
} while ((val % *fact) == 0);
|
|
|
|
/* Let the user know we're doing something. */
|
|
(void)fflush(stdout);
|
|
}
|
|
(void)putchar('\n');
|
|
}
|
|
|
|
void
|
|
usage()
|
|
{
|
|
(void)fprintf(stderr, "usage: factor -h [value ...]\n");
|
|
exit (0);
|
|
}
|