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-rw-r--r--security/nss/lib/freebl/mpi/utils/sieve.c265
1 files changed, 0 insertions, 265 deletions
diff --git a/security/nss/lib/freebl/mpi/utils/sieve.c b/security/nss/lib/freebl/mpi/utils/sieve.c
deleted file mode 100644
index 4dd20604c..000000000
--- a/security/nss/lib/freebl/mpi/utils/sieve.c
+++ /dev/null
@@ -1,265 +0,0 @@
-/*
- * sieve.c
- *
- * Finds prime numbers using the Sieve of Eratosthenes
- *
- * This implementation uses a bitmap to represent all odd integers in a
- * given range. We iterate over this bitmap, crossing off the
- * multiples of each prime we find. At the end, all the remaining set
- * bits correspond to prime integers.
- *
- * Here, we make two passes -- once we have generated a sieve-ful of
- * primes, we copy them out, reset the sieve using the highest
- * generated prime from the first pass as a base. Then we cross out
- * all the multiples of all the primes we found the first time through,
- * and re-sieve. In this way, we get double use of the memory we
- * allocated for the sieve the first time though. Since we also
- * implicitly ignore multiples of 2, this amounts to 4 times the
- * values.
- *
- * This could (and probably will) be generalized to re-use the sieve a
- * few more times.
- *
- * The contents of this file are subject to the Mozilla Public
- * License Version 1.1 (the "License"); you may not use this file
- * except in compliance with the License. You may obtain a copy of
- * the License at http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS
- * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
- * implied. See the License for the specific language governing
- * rights and limitations under the License.
- *
- * The Original Code is the MPI Arbitrary Precision Integer Arithmetic
- * library.
- *
- * The Initial Developer of the Original Code is Michael J. Fromberger.
- * Portions created by Michael J. Fromberger are
- * Copyright (C) 1998, 1999, 2000 Michael J. Fromberger.
- * All Rights Reserved.
- *
- * Contributor(s):
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License Version 2 or later (the
- * "GPL"), in which case the provisions of the GPL are applicable
- * instead of those above. If you wish to allow use of your
- * version of this file only under the terms of the GPL and not to
- * allow others to use your version of this file under the MPL,
- * indicate your decision by deleting the provisions above and
- * replace them with the notice and other provisions required by
- * the GPL. If you do not delete the provisions above, a recipient
- * may use your version of this file under either the MPL or the GPL.
- *
- * $Id$
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <limits.h>
-
-typedef unsigned char byte;
-
-typedef struct {
- int size;
- byte *bits;
- long base;
- int next;
- int nbits;
-} sieve;
-
-void sieve_init(sieve *sp, long base, int nbits);
-void sieve_grow(sieve *sp, int nbits);
-long sieve_next(sieve *sp);
-void sieve_reset(sieve *sp, long base);
-void sieve_cross(sieve *sp, long val);
-void sieve_clear(sieve *sp);
-
-#define S_ISSET(S, B) (((S)->bits[(B)/CHAR_BIT]>>((B)%CHAR_BIT))&1)
-#define S_SET(S, B) ((S)->bits[(B)/CHAR_BIT]|=(1<<((B)%CHAR_BIT)))
-#define S_CLR(S, B) ((S)->bits[(B)/CHAR_BIT]&=~(1<<((B)%CHAR_BIT)))
-#define S_VAL(S, B) ((S)->base+(2*(B)))
-#define S_BIT(S, V) (((V)-((S)->base))/2)
-
-int main(int argc, char *argv[])
-{
- sieve s;
- long pr, *p;
- int c, ix, cur = 0;
-
- if(argc < 2) {
- fprintf(stderr, "Usage: %s <width>\n", argv[0]);
- return 1;
- }
-
- c = atoi(argv[1]);
- if(c < 0) c = -c;
-
- fprintf(stderr, "%s: sieving to %d positions\n", argv[0], c);
-
- sieve_init(&s, 3, c);
-
- c = 0;
- while((pr = sieve_next(&s)) > 0) {
- ++c;
- }
-
- p = calloc(c, sizeof(long));
- if(!p) {
- fprintf(stderr, "%s: out of memory after first half\n", argv[0]);
- sieve_clear(&s);
- exit(1);
- }
-
- fprintf(stderr, "%s: half done ... \n", argv[0]);
-
- for(ix = 0; ix < s.nbits; ix++) {
- if(S_ISSET(&s, ix)) {
- p[cur] = S_VAL(&s, ix);
- printf("%ld\n", p[cur]);
- ++cur;
- }
- }
-
- sieve_reset(&s, p[cur - 1]);
- fprintf(stderr, "%s: crossing off %d found primes ... \n", argv[0], cur);
- for(ix = 0; ix < cur; ix++) {
- sieve_cross(&s, p[ix]);
- if(!(ix % 1000))
- fputc('.', stderr);
- }
- fputc('\n', stderr);
-
- free(p);
-
- fprintf(stderr, "%s: sieving again from %ld ... \n", argv[0], p[cur - 1]);
- c = 0;
- while((pr = sieve_next(&s)) > 0) {
- ++c;
- }
-
- fprintf(stderr, "%s: done!\n", argv[0]);
- for(ix = 0; ix < s.nbits; ix++) {
- if(S_ISSET(&s, ix)) {
- printf("%ld\n", S_VAL(&s, ix));
- }
- }
-
- sieve_clear(&s);
-
- return 0;
-}
-
-void sieve_init(sieve *sp, long base, int nbits)
-{
- sp->size = (nbits / CHAR_BIT);
-
- if(nbits % CHAR_BIT)
- ++sp->size;
-
- sp->bits = calloc(sp->size, sizeof(byte));
- memset(sp->bits, UCHAR_MAX, sp->size);
- if(!(base & 1))
- ++base;
- sp->base = base;
-
- sp->next = 0;
- sp->nbits = sp->size * CHAR_BIT;
-}
-
-void sieve_grow(sieve *sp, int nbits)
-{
- int ns = (nbits / CHAR_BIT);
-
- if(nbits % CHAR_BIT)
- ++ns;
-
- if(ns > sp->size) {
- byte *tmp;
- int ix;
-
- tmp = calloc(ns, sizeof(byte));
- if(tmp == NULL) {
- fprintf(stderr, "Error: out of memory in sieve_grow\n");
- return;
- }
-
- memcpy(tmp, sp->bits, sp->size);
- for(ix = sp->size; ix < ns; ix++) {
- tmp[ix] = UCHAR_MAX;
- }
-
- free(sp->bits);
- sp->bits = tmp;
- sp->size = ns;
-
- sp->nbits = sp->size * CHAR_BIT;
- }
-}
-
-long sieve_next(sieve *sp)
-{
- long out;
- int ix = 0;
- long val;
-
- if(sp->next > sp->nbits)
- return -1;
-
- out = S_VAL(sp, sp->next);
-#ifdef DEBUG
- fprintf(stderr, "Sieving %ld\n", out);
-#endif
-
- /* Sieve out all multiples of the current prime */
- val = out;
- while(ix < sp->nbits) {
- val += out;
- ix = S_BIT(sp, val);
- if((val & 1) && ix < sp->nbits) { /* && S_ISSET(sp, ix)) { */
- S_CLR(sp, ix);
-#ifdef DEBUG
- fprintf(stderr, "Crossing out %ld (bit %d)\n", val, ix);
-#endif
- }
- }
-
- /* Scan ahead to the next prime */
- ++sp->next;
- while(sp->next < sp->nbits && !S_ISSET(sp, sp->next))
- ++sp->next;
-
- return out;
-}
-
-void sieve_cross(sieve *sp, long val)
-{
- int ix = 0;
- long cur = val;
-
- while(cur < sp->base)
- cur += val;
-
- ix = S_BIT(sp, cur);
- while(ix < sp->nbits) {
- if(cur & 1)
- S_CLR(sp, ix);
- cur += val;
- ix = S_BIT(sp, cur);
- }
-}
-
-void sieve_reset(sieve *sp, long base)
-{
- memset(sp->bits, UCHAR_MAX, sp->size);
- sp->base = base;
- sp->next = 0;
-}
-
-void sieve_clear(sieve *sp)
-{
- if(sp->bits)
- free(sp->bits);
-
- sp->bits = NULL;
-}
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