diff libtommath/bn_mp_copy.c @ 389:5ff8218bcee9

propagate from branch 'au.asn.ucc.matt.ltm.dropbear' (head 2af95f00ebd5bb7a28b3817db1218442c935388e) to branch 'au.asn.ucc.matt.dropbear' (head ecd779509ef23a8cdf64888904fc9b31d78aa933)
author Matt Johnston <matt@ucc.asn.au>
date Thu, 11 Jan 2007 03:14:55 +0000
parents eed26cff980b
children 60fc6476e044
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libtommath/bn_mp_copy.c	Thu Jan 11 03:14:55 2007 +0000
@@ -0,0 +1,68 @@
+#include <tommath.h>
+#ifdef BN_MP_COPY_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis
+ *
+ * LibTomMath is a library that provides multiple-precision
+ * integer arithmetic as well as number theoretic functionality.
+ *
+ * The library was designed directly after the MPI library by
+ * Michael Fromberger but has been written from scratch with
+ * additional optimizations in place.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, [email protected], http://math.libtomcrypt.com
+ */
+
+/* copy, b = a */
+int
+mp_copy (mp_int * a, mp_int * b)
+{
+  int     res, n;
+
+  /* if dst == src do nothing */
+  if (a == b) {
+    return MP_OKAY;
+  }
+
+  /* grow dest */
+  if (b->alloc < a->used) {
+     if ((res = mp_grow (b, a->used)) != MP_OKAY) {
+        return res;
+     }
+  }
+
+  /* zero b and copy the parameters over */
+  {
+    register mp_digit *tmpa, *tmpb;
+
+    /* pointer aliases */
+
+    /* source */
+    tmpa = a->dp;
+
+    /* destination */
+    tmpb = b->dp;
+
+    /* copy all the digits */
+    for (n = 0; n < a->used; n++) {
+      *tmpb++ = *tmpa++;
+    }
+
+    /* clear high digits */
+    for (; n < b->used; n++) {
+      *tmpb++ = 0;
+    }
+  }
+
+  /* copy used count and sign */
+  b->used = a->used;
+  b->sign = a->sign;
+  return MP_OKAY;
+}
+#endif
+
+/* $Source: /cvs/libtom/libtommath/bn_mp_copy.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2006/03/31 14:18:44 $ */