crypto/external/bsd/heimdal/dist/lib/hcrypto/libtommath/bn_mp_clamp.c

   1 /*      $NetBSD: bn_mp_clamp.c,v 1.1.1.2 2014/04/24 12:45:31 pettai Exp $       */
   2
   3 #include <tommath.h>
   4 #ifdef BN_MP_CLAMP_C
   5 /* LibTomMath, multiple-precision integer library -- Tom St Denis
   6  *
   7  * LibTomMath is a library that provides multiple-precision
   8  * integer arithmetic as well as number theoretic functionality.
   9  *
  10  * The library was designed directly after the MPI library by
  11  * Michael Fromberger but has been written from scratch with
  12  * additional optimizations in place.
  13  *
  14  * The library is free for all purposes without any express
  15  * guarantee it works.
  16  *
  17  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
  18  */
  19
  20 /* trim unused digits
  21  *
  22  * This is used to ensure that leading zero digits are
  23  * trimed and the leading "used" digit will be non-zero
  24  * Typically very fast.  Also fixes the sign if there
  25  * are no more leading digits
  26  */
  27 void
  28 mp_clamp (mp_int * a)
  29 {
  30   /* decrease used while the most significant digit is
  31    * zero.
  32    */
  33   while (a->used > 0 && a->dp[a->used - 1] == 0) {
  34     --(a->used);
  35   }
  36
  37   /* reset the sign flag if used == 0 */
  38   if (a->used == 0) {
  39     a->sign = MP_ZPOS;
  40   }
  41 }
  42 #endif
  43
  44 /* Source: /cvs/libtom/libtommath/bn_mp_clamp.c,v  */
  45 /* Revision: 1.4  */
  46 /* Date: 2006/12/28 01:25:13  */