1 /*
2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Landon Curt Noll.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1989, 1993\n\
36 The Regents of the University of California. All rights reserved.\n";
37 #endif /* not lint */
38
39 #ifndef lint
40 #if 0
41 static char sccsid[] = "@(#)primes.c 8.5 (Berkeley) 5/10/95";
42 #endif
43 static const char rcsid[] =
44 "$FreeBSD$";
45 #endif /* not lint */
46
47 /*
48 * primes - generate a table of primes between two values
49 *
50 * By: Landon Curt Noll [email protected], ...!{sun,tolsoft}!hoptoad!chongo
51 *
52 * chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\
53 *
54 * usage:
55 * primes [-h] [start [stop]]
56 *
57 * Print primes >= start and < stop. If stop is omitted,
58 * the value 4294967295 (2^32-1) is assumed. If start is
59 * omitted, start is read from standard input.
60 *
61 * validation check: there are 664579 primes between 0 and 10^7
62 */
63
64 #include <capsicum_helpers.h>
65 #include <ctype.h>
66 #include <err.h>
67 #include <errno.h>
68 #include <inttypes.h>
69 #include <limits.h>
70 #include <math.h>
71 #include <stdio.h>
72 #include <stdlib.h>
73 #include <string.h>
74 #include <nl_types.h>
75 #include <unistd.h>
76
77 #include "primes.h"
78
79 /*
80 * Eratosthenes sieve table
81 *
82 * We only sieve the odd numbers. The base of our sieve windows are always
83 * odd. If the base of table is 1, table[i] represents 2*i-1. After the
84 * sieve, table[i] == 1 if and only if 2*i-1 is prime.
85 *
86 * We make TABSIZE large to reduce the overhead of inner loop setup.
87 */
88 static char table[TABSIZE]; /* Eratosthenes sieve of odd numbers */
89
90 static int hflag;
91
92 static void primes(ubig, ubig);
93 static ubig read_num_buf(void);
94 static void usage(void);
95
96 int
main(int argc,char * argv[])97 main(int argc, char *argv[])
98 {
99 ubig start; /* where to start generating */
100 ubig stop; /* don't generate at or above this value */
101 int ch;
102 char *p;
103
104 caph_cache_catpages();
105 if (caph_enter() < 0)
106 err(1, "cap_enter");
107
108 while ((ch = getopt(argc, argv, "h")) != -1)
109 switch (ch) {
110 case 'h':
111 hflag++;
112 break;
113 case '?':
114 default:
115 usage();
116 }
117 argc -= optind;
118 argv += optind;
119
120 start = 0;
121 stop = (uint64_t)(-1);
122
123 /*
124 * Convert low and high args. Strtoumax(3) sets errno to
125 * ERANGE if the number is too large, but, if there's
126 * a leading minus sign it returns the negation of the
127 * result of the conversion, which we'd rather disallow.
128 */
129 switch (argc) {
130 case 2:
131 /* Start and stop supplied on the command line. */
132 if (argv[0][0] == '-' || argv[1][0] == '-')
133 errx(1, "negative numbers aren't permitted.");
134
135 errno = 0;
136 start = strtoumax(argv[0], &p, 0);
137 if (errno)
138 err(1, "%s", argv[0]);
139 if (*p != '\0')
140 errx(1, "%s: illegal numeric format.", argv[0]);
141
142 errno = 0;
143 stop = strtoumax(argv[1], &p, 0);
144 if (errno)
145 err(1, "%s", argv[1]);
146 if (*p != '\0')
147 errx(1, "%s: illegal numeric format.", argv[1]);
148 break;
149 case 1:
150 /* Start on the command line. */
151 if (argv[0][0] == '-')
152 errx(1, "negative numbers aren't permitted.");
153
154 errno = 0;
155 start = strtoumax(argv[0], &p, 0);
156 if (errno)
157 err(1, "%s", argv[0]);
158 if (*p != '\0')
159 errx(1, "%s: illegal numeric format.", argv[0]);
160 break;
161 case 0:
162 start = read_num_buf();
163 break;
164 default:
165 usage();
166 }
167
168 if (start > stop)
169 errx(1, "start value must be less than stop value.");
170 primes(start, stop);
171 return (0);
172 }
173
174 /*
175 * read_num_buf --
176 * This routine returns a number n, where 0 <= n && n <= BIG.
177 */
178 static ubig
read_num_buf(void)179 read_num_buf(void)
180 {
181 ubig val;
182 char *p, buf[LINE_MAX]; /* > max number of digits. */
183
184 for (;;) {
185 if (fgets(buf, sizeof(buf), stdin) == NULL) {
186 if (ferror(stdin))
187 err(1, "stdin");
188 exit(0);
189 }
190 for (p = buf; isblank(*p); ++p);
191 if (*p == '\n' || *p == '\0')
192 continue;
193 if (*p == '-')
194 errx(1, "negative numbers aren't permitted.");
195 errno = 0;
196 val = strtoumax(buf, &p, 0);
197 if (errno)
198 err(1, "%s", buf);
199 if (*p != '\n')
200 errx(1, "%s: illegal numeric format.", buf);
201 return (val);
202 }
203 }
204
205 /*
206 * primes - sieve and print primes from start up to and but not including stop
207 */
208 static void
primes(ubig start,ubig stop)209 primes(ubig start, ubig stop)
210 {
211 char *q; /* sieve spot */
212 ubig factor; /* index and factor */
213 char *tab_lim; /* the limit to sieve on the table */
214 const ubig *p; /* prime table pointer */
215 ubig fact_lim; /* highest prime for current block */
216 ubig mod; /* temp storage for mod */
217
218 /*
219 * A number of systems can not convert double values into unsigned
220 * longs when the values are larger than the largest signed value.
221 * We don't have this problem, so we can go all the way to BIG.
222 */
223 if (start < 3) {
224 start = (ubig)2;
225 }
226 if (stop < 3) {
227 stop = (ubig)2;
228 }
229 if (stop <= start) {
230 return;
231 }
232
233 /*
234 * be sure that the values are odd, or 2
235 */
236 if (start != 2 && (start&0x1) == 0) {
237 ++start;
238 }
239 if (stop != 2 && (stop&0x1) == 0) {
240 ++stop;
241 }
242
243 /*
244 * quick list of primes <= pr_limit
245 */
246 if (start <= *pr_limit) {
247 /* skip primes up to the start value */
248 for (p = &prime[0], factor = prime[0];
249 factor < stop && p <= pr_limit; factor = *(++p)) {
250 if (factor >= start) {
251 printf(hflag ? "%" PRIx64 "\n" : "%" PRIu64 "\n", factor);
252 }
253 }
254 /* return early if we are done */
255 if (p <= pr_limit) {
256 return;
257 }
258 start = *pr_limit+2;
259 }
260
261 /*
262 * we shall sieve a bytemap window, note primes and move the window
263 * upward until we pass the stop point
264 */
265 while (start < stop) {
266 /*
267 * factor out 3, 5, 7, 11 and 13
268 */
269 /* initial pattern copy */
270 factor = (start%(2*3*5*7*11*13))/2; /* starting copy spot */
271 memcpy(table, &pattern[factor], pattern_size-factor);
272 /* main block pattern copies */
273 for (fact_lim=pattern_size-factor;
274 fact_lim+pattern_size<=TABSIZE; fact_lim+=pattern_size) {
275 memcpy(&table[fact_lim], pattern, pattern_size);
276 }
277 /* final block pattern copy */
278 memcpy(&table[fact_lim], pattern, TABSIZE-fact_lim);
279
280 /*
281 * sieve for primes 17 and higher
282 */
283 /* note highest useful factor and sieve spot */
284 if (stop-start > TABSIZE+TABSIZE) {
285 tab_lim = &table[TABSIZE]; /* sieve it all */
286 fact_lim = sqrt(start+1.0+TABSIZE+TABSIZE);
287 } else {
288 tab_lim = &table[(stop-start)/2]; /* partial sieve */
289 fact_lim = sqrt(stop+1.0);
290 }
291 /* sieve for factors >= 17 */
292 factor = 17; /* 17 is first prime to use */
293 p = &prime[7]; /* 19 is next prime, pi(19)=7 */
294 do {
295 /* determine the factor's initial sieve point */
296 mod = start%factor;
297 if (mod & 0x1) {
298 q = &table[(factor-mod)/2];
299 } else {
300 q = &table[mod ? factor-(mod/2) : 0];
301 }
302 /* sive for our current factor */
303 for ( ; q < tab_lim; q += factor) {
304 *q = '\0'; /* sieve out a spot */
305 }
306 factor = *p++;
307 } while (factor <= fact_lim);
308
309 /*
310 * print generated primes
311 */
312 for (q = table; q < tab_lim; ++q, start+=2) {
313 if (*q) {
314 if (start > SIEVEMAX) {
315 if (!isprime(start))
316 continue;
317 }
318 printf(hflag ? "%" PRIx64 "\n" : "%" PRIu64 "\n", start);
319 }
320 }
321 }
322 }
323
324 static void
usage(void)325 usage(void)
326 {
327 fprintf(stderr, "usage: primes [-h] [start [stop]]\n");
328 exit(1);
329 }
330