release/src/router/dropbear/libtommath/bn_mp_clear.c

   1 #include <tommath.h>
   2 #ifdef BN_MP_CLEAR_C
   3 /* LibTomMath, multiple-precision integer library -- Tom St Denis
   4  *
   5  * LibTomMath is a library that provides multiple-precision
   6  * integer arithmetic as well as number theoretic functionality.
   7  *
   8  * The library was designed directly after the MPI library by
   9  * Michael Fromberger but has been written from scratch with
  10  * additional optimizations in place.
  11  *
  12  * The library is free for all purposes without any express
  13  * guarantee it works.
  14  *
  15  * Tom St Denis, tomstdenis@gmail.com, http://math.libtomcrypt.com
  16  */
  17
  18 /* clear one (frees)  */
  19 void
  20 mp_clear (mp_int * a)
  21 {
  22   volatile mp_digit *p;
  23   int len;
  24
  25   /* only do anything if a hasn't been freed previously */
  26   if (a->dp != NULL) {
  27     /* first zero the digits */
  28         len = a->alloc;
  29         p = a->dp;
  30         while (len--) {
  31                 *p++ = 0;
  32         }
  33
  34     /* free ram */
  35     XFREE(a->dp);
  36
  37     /* reset members to make debugging easier */
  38     a->dp    = NULL;
  39     a->alloc = a->used = 0;
  40     a->sign  = MP_ZPOS;
  41   }
  42 }
  43 #endif
  44
  45 /* $Source: /cvs/libtom/libtommath/bn_mp_clear.c,v $ */
  46 /* $Revision: 1.3 $ */
  47 /* $Date: 2006/03/31 14:18:44 $ */