--- a/libtommath/bn_mp_montgomery_calc_normalization.c	Wed Feb 28 22:11:39 2018 +0800
+++ b/libtommath/bn_mp_montgomery_calc_normalization.c	Thu Oct 15 19:55:15 2020 +0800
@@ -1,19 +1,7 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
 #ifdef BN_MP_MONTGOMERY_CALC_NORMALIZATION_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://libtom.org
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
 
 /*
  * shifts with subtractions when the result is greater than b.
@@ -21,39 +9,36 @@
  * The method is slightly modified to shift B unconditionally upto just under
  * the leading bit of b.  This saves alot of multiple precision shifting.
  */
-int mp_montgomery_calc_normalization (mp_int * a, mp_int * b)
+mp_err mp_montgomery_calc_normalization(mp_int *a, const mp_int *b)
 {
-  int     x, bits, res;
+   int    x, bits;
+   mp_err err;
 
-  /* how many bits of last digit does b use */
-  bits = mp_count_bits (b) % DIGIT_BIT;
+   /* how many bits of last digit does b use */
+   bits = mp_count_bits(b) % MP_DIGIT_BIT;
 
-  if (b->used > 1) {
-     if ((res = mp_2expt (a, ((b->used - 1) * DIGIT_BIT) + bits - 1)) != MP_OKAY) {
-        return res;
-     }
-  } else {
-     mp_set(a, 1);
-     bits = 1;
-  }
+   if (b->used > 1) {
+      if ((err = mp_2expt(a, ((b->used - 1) * MP_DIGIT_BIT) + bits - 1)) != MP_OKAY) {
+         return err;
+      }
+   } else {
+      mp_set(a, 1uL);
+      bits = 1;
+   }
 
 
-  /* now compute C = A * B mod b */
-  for (x = bits - 1; x < (int)DIGIT_BIT; x++) {
-    if ((res = mp_mul_2 (a, a)) != MP_OKAY) {
-      return res;
-    }
-    if (mp_cmp_mag (a, b) != MP_LT) {
-      if ((res = s_mp_sub (a, b, a)) != MP_OKAY) {
-        return res;
+   /* now compute C = A * B mod b */
+   for (x = bits - 1; x < (int)MP_DIGIT_BIT; x++) {
+      if ((err = mp_mul_2(a, a)) != MP_OKAY) {
+         return err;
       }
-    }
-  }
+      if (mp_cmp_mag(a, b) != MP_LT) {
+         if ((err = s_mp_sub(a, b, a)) != MP_OKAY) {
+            return err;
+         }
+      }
+   }
 
-  return MP_OKAY;
+   return MP_OKAY;
 }
 #endif
-
-/* ref:         $Format:%D$ */
-/* git commit:  $Format:%H$ */
-/* commit time: $Format:%ai$ */