/* -*-c-*-
*
- * $Id: pgen.c,v 1.8 2002/01/13 13:42:53 mdw Exp $
+ * $Id: pgen.c,v 1.10 2004/04/08 01:36:15 mdw Exp $
*
* Prime generation glue
*
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: pgen.c,v $
- * Revision 1.8 2002/01/13 13:42:53 mdw
- * More efficient Rabin-Miller test: with random witnesses, skip redundant
- * Montgomerization. (Being bijective, it can't affect the distribution.)
- *
- * Revision 1.7 2001/02/03 16:05:32 mdw
- * Now @mp_drop@ checks its argument is non-NULL before attempting to free
- * it. Note that the macro version @MP_DROP@ doesn't do this.
- *
- * Revision 1.6 2000/10/08 12:11:22 mdw
- * Use @MP_EQ@ instead of @MP_CMP@.
- *
- * Revision 1.5 2000/06/17 11:52:36 mdw
- * Signal a pgen abort if the jump and base share a common factor.
- *
- * Revision 1.4 1999/12/22 16:01:11 mdw
- * Same file, completely different code. Main interface for new prime-
- * search system.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <assert.h>
return (ev.m);
}
+/* --- @pgen_primep@ --- *
+ *
+ * Arguments: @mp *p@ = a number to check
+ * @grand *gr@ = a random number source
+ *
+ * Returns: Nonzero if @p@ is really prime.
+ */
+
+int pgen_primep(mp *p, grand *gr)
+{
+ int i = rabin_iters(mp_bits(p));
+ rabin r;
+ mp *x = MP_NEW;
+
+ if (MP_ISNEG(p)) return (0);
+ switch (pfilt_smallfactor(p)) {
+ case PGEN_DONE: return (1);
+ case PGEN_FAIL: return (0);
+ }
+ rabin_create(&r, p);
+ while (i) {
+ x = mprand_range(x, p, gr, 0);
+ if (rabin_rtest(&r, x) == PGEN_FAIL)
+ break;
+ i--;
+ }
+ MP_DROP(x);
+ rabin_destroy(&r);
+ return (!i);
+}
+
/*----- Test rig ----------------------------------------------------------*/
#ifdef TEST_RIG