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-rw-r--r--libtommath/bn_mp_mod_2d.c73
1 files changed, 28 insertions, 45 deletions
diff --git a/libtommath/bn_mp_mod_2d.c b/libtommath/bn_mp_mod_2d.c
index 2bb86da..5bf57a1 100644
--- a/libtommath/bn_mp_mod_2d.c
+++ b/libtommath/bn_mp_mod_2d.c
@@ -1,55 +1,38 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_MP_MOD_2D_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, tstdenis82@gmail.com, http://libtom.org
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
/* calc a value mod 2**b */
-int
-mp_mod_2d (mp_int * a, int b, mp_int * c)
+mp_err mp_mod_2d(const mp_int *a, int b, mp_int *c)
{
- int x, res;
+ int x;
+ mp_err err;
- /* if b is <= 0 then zero the int */
- if (b <= 0) {
- mp_zero (c);
- return MP_OKAY;
- }
+ /* if b is <= 0 then zero the int */
+ if (b <= 0) {
+ mp_zero(c);
+ return MP_OKAY;
+ }
- /* if the modulus is larger than the value than return */
- if (b >= (int) (a->used * DIGIT_BIT)) {
- res = mp_copy (a, c);
- return res;
- }
+ /* if the modulus is larger than the value than return */
+ if (b >= (a->used * MP_DIGIT_BIT)) {
+ return mp_copy(a, c);
+ }
- /* copy */
- if ((res = mp_copy (a, c)) != MP_OKAY) {
- return res;
- }
+ /* copy */
+ if ((err = mp_copy(a, c)) != MP_OKAY) {
+ return err;
+ }
- /* zero digits above the last digit of the modulus */
- for (x = (b / DIGIT_BIT) + (((b % DIGIT_BIT) == 0) ? 0 : 1); x < c->used; x++) {
- c->dp[x] = 0;
- }
- /* clear the digit that is not completely outside/inside the modulus */
- c->dp[b / DIGIT_BIT] &=
- (mp_digit) ((((mp_digit) 1) << (((mp_digit) b) % DIGIT_BIT)) - ((mp_digit) 1));
- mp_clamp (c);
- return MP_OKAY;
+ /* zero digits above the last digit of the modulus */
+ x = (b / MP_DIGIT_BIT) + (((b % MP_DIGIT_BIT) == 0) ? 0 : 1);
+ MP_ZERO_DIGITS(c->dp + x, c->used - x);
+
+ /* clear the digit that is not completely outside/inside the modulus */
+ c->dp[b / MP_DIGIT_BIT] &=
+ ((mp_digit)1 << (mp_digit)(b % MP_DIGIT_BIT)) - (mp_digit)1;
+ mp_clamp(c);
+ return MP_OKAY;
}
#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */