fixed problem with overflow

Author: czurnieden

s_mp_faster_to_radix.c

@@ -14,7 +14,7 @@ static int32_t s_floor_ilog2(int32_t value)
 }
 
 /* Exponentiation with small footprint */
-/*
+
 static int32_t s_pow(int32_t base, int32_t exponent)
 {
    int32_t result = 1;
@@ -23,11 +23,14 @@ static int32_t s_pow(int32_t base, int32_t exponent)
          result *= base;
       }
       exponent /= 2;
+      if (exponent == 0) {
+         break;
+      }
       base *= base;
    }
    return result;
 }
-*/
+
 static mp_err s_mp_to_radix_recursive(const mp_int *a, char **str, size_t *part_maxlen, size_t *part_written,
                                       int radix, int32_t k, int32_t t, bool pad, mp_int *P, mp_int *R)
 {
@@ -101,20 +104,13 @@ mp_err s_mp_faster_to_radix(const mp_int *a, char *str, size_t maxlen, size_t *w
    size_t part_written = 0;
    size_t part_maxlen = maxlen;
 
-   mp_int N;
-
    /* List of reciprocals */
    mp_int *R = NULL;
    /* List of moduli */
    mp_int *P = NULL;
 
    /* Denominator for the reciprocal: b^y */
-   /*n = s_pow((int32_t)radix, (int32_t)s_mp_radix_exponent_y[radix]);*/
-   /* FIXME: either do it full in bigint or fix the problem with the sanitizer */
-   if ((err = mp_init_i32(&N,(int32_t)radix)) != MP_OKAY)                                               goto LTM_ERR;
-   if ((err = mp_expt_n(&N, (int)s_mp_radix_exponent_y[radix], &N)) != MP_OKAY)                         goto LTM_ERR;
-   n = mp_get_i32(&N);
-   mp_clear(&N);
+   n = s_pow((int32_t)radix, (int32_t)s_mp_radix_exponent_y[radix]);
 
    /* Numerator of the reciprocal: ceil(log_2(n)) */
    k = s_floor_ilog2(n) + 1;

tommath_class.h

@@ -1069,7 +1069,6 @@
 #   define MP_DIV_2D_C
 #   define MP_DIV_C
 #   define MP_EXPT_N_C
-#   define MP_GET_I32_C
 #   define MP_INIT_C
 #   define MP_INIT_I32_C
 #   define MP_INIT_MULTI_C