#include "tommath_private.h"

#ifdef BN_MP_GROW_C

/* LibTomMath, multiple-precision integer library -- Tom St Denis */

/* SPDX-License-Identifier: Unlicense */

/* grow as required */

mp_err mp_grow(mp_int *a, int size)

{

   int     i;

   mp_digit *tmp;

   /* if the alloc size is smaller alloc more ram */

   if (a->alloc < size) {

      /* reallocate the array a->dp

       *

       * We store the return in a temporary variable

       * in case the operation failed we don't want

       * to overwrite the dp member of a.

       */

      tmp = (mp_digit *) MP_REALLOC(a->dp,

                                    (size_t)a->alloc * sizeof(mp_digit),

                                    (size_t)size * sizeof(mp_digit));

      if (tmp == NULL) {

         /* reallocation failed but "a" is still valid [can be freed] */

         return MP_MEM;

      }

      /* reallocation succeeded so set a->dp */

      a->dp = tmp;

      /* zero excess digits */

      i        = a->alloc;

      a->alloc = size;

      MP_ZERO_DIGITS(a->dp + i, a->alloc - i);

   }

   return MP_OKAY;

}

#endif