Search for primitive elements using prime-search equipment.

diff --git a/prim.c b/prim.c
new file mode 100644 (file)
index 0000000..bdad98b
--- /dev/null
+++ b/prim.c
@@ -0,0 +1,107 @@
+/* -*-c-*-
+ *
+ * $Id: prim.c,v 1.1 1999/12/22 15:58:59 mdw Exp $
+ *
+ * Finding primitive elements
+ *
+ * (c) 1999 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------* 
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ * 
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Revision history --------------------------------------------------* 
+ *
+ * $Log: prim.c,v $
+ * Revision 1.1  1999/12/22 15:58:59  mdw
+ * Search for primitive elements using prime-search equipment.
+ *
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include "mp.h"
+#include "mpint.h"
+#include "mpmont.h"
+#include "mprand.h"
+#include "pgen.h"
+#include "prim.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @prim_test@ --- */
+
+int prim_test(int rq, pgen_event *ev, void *p)
+{
+  prim_ctx *c = p;
+  int rc = rq;
+
+  switch (rq) {
+    case PGEN_BEGIN:
+      return (PGEN_TRY);
+    case PGEN_TRY: {
+      mp *x = MP_NEW;
+      mp *f = c->f;
+      rc = PGEN_FAIL;
+
+      x = mpmont_exp(&c->mm, x, ev->m, f);
+      if (MP_CMP(x, ==, MP_ONE))
+       goto done;
+      if (c->n == 0) {
+       mp_drop(ev->m);
+       ev->m = MP_COPY(x);
+      } else {
+       size_t n = c->n - 1;
+       f++;
+       while (n) {
+         x = mpmont_exp(&c->mm, x, ev->m, f);
+         if (MP_CMP(x, ==, MP_ONE))
+           goto done;
+         n--; f++;
+       }
+      }
+      rc = PGEN_DONE;
+    done:
+      mp_drop(x);
+    } break;
+  }
+
+  return (rc);
+}
+
+/* --- Trivial stepping functions -----------------------------------------*/
+
+/* --- @prim_step@ --- */
+
+int prim_step(int rq, pgen_event *ev, void *p)
+{
+  unsigned *i = p;
+  switch (rq) {
+    case PGEN_BEGIN:
+    case PGEN_TRY:
+      if (*i >= NPRIME)
+       return PGEN_FAIL;
+      ev->m = mp_fromint(ev->m, primetab[(*i)++]);
+      return (PGEN_TRY);
+  }
+  return (0);
+}
+
+/*----- That's all, folks -------------------------------------------------*/

diff --git a/prim.h b/prim.h
new file mode 100644 (file)
index 0000000..30392cd
--- /dev/null
+++ b/prim.h
@@ -0,0 +1,91 @@
+/* -*-c-*-
+ *
+ * $Id: prim.h,v 1.1 1999/12/22 15:58:59 mdw Exp $
+ *
+ * Finding primitive elements
+ *
+ * (c) 1999 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------* 
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ * 
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Library General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Revision history --------------------------------------------------* 
+ *
+ * $Log: prim.h,v $
+ * Revision 1.1  1999/12/22 15:58:59  mdw
+ * Search for primitive elements using prime-search equipment.
+ *
+ */
+
+#ifndef CATACOMB_PRIM_H
+#define CATACOMB_PRIM_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <stddef.h>
+
+#ifndef CATACOMB_MP_H
+#  include "mp.h"
+#endif
+
+#ifndef CATACOMB_MPMONT_H
+#  include "mpmont.h"
+#endif
+
+#ifndef CATACOMB_PGEN_H
+#  include "pgen.h"
+#endif
+
+/*----- Data structures ---------------------------------------------------*/
+
+/* --- @prim_ctx@ --- *
+ *
+ * All fields must be configured by the client.  Set @n@ to zero to discover
+ * generators of the subgroup of order %$m / f$%.
+ */
+
+typedef struct prim_ctx {
+  mpmont mm;                           /* Montgomery context for modulus */
+  mp *f;                               /* Array of factors */
+  size_t n;                            /* Number of factors */
+} prim_ctx;
+
+/*----- Functions provided ------------------------------------------------*/
+
+/* --- @prim_test@ --- */
+
+extern int prim_test(int /*rq*/, pgen_event */*ev*/, void */*p*/);
+
+/* --- @prim_step@ --- */
+
+extern int prim_step(int /*rq*/, pgen_event */*ev*/, void */*p*/);
+
+/*----- That's all, folks -------------------------------------------------*/
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif