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-rw-r--r--libtommath/bn_mp_mul_d.c102
1 files changed, 42 insertions, 60 deletions
diff --git a/libtommath/bn_mp_mul_d.c b/libtommath/bn_mp_mul_d.c
index 6954ed3..b56dfa3 100644
--- a/libtommath/bn_mp_mul_d.c
+++ b/libtommath/bn_mp_mul_d.c
@@ -1,79 +1,61 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_MP_MUL_D_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 */
/* multiply by a digit */
-int
-mp_mul_d (mp_int * a, mp_digit b, mp_int * c)
+mp_err mp_mul_d(const mp_int *a, mp_digit b, mp_int *c)
{
- mp_digit u, *tmpa, *tmpc;
- mp_word r;
- int ix, res, olduse;
+ mp_digit u, *tmpa, *tmpc;
+ mp_word r;
+ mp_err err;
+ int ix, olduse;
- /* make sure c is big enough to hold a*b */
- if (c->alloc < (a->used + 1)) {
- if ((res = mp_grow (c, a->used + 1)) != MP_OKAY) {
- return res;
- }
- }
+ /* make sure c is big enough to hold a*b */
+ if (c->alloc < (a->used + 1)) {
+ if ((err = mp_grow(c, a->used + 1)) != MP_OKAY) {
+ return err;
+ }
+ }
- /* get the original destinations used count */
- olduse = c->used;
+ /* get the original destinations used count */
+ olduse = c->used;
- /* set the sign */
- c->sign = a->sign;
+ /* set the sign */
+ c->sign = a->sign;
- /* alias for a->dp [source] */
- tmpa = a->dp;
+ /* alias for a->dp [source] */
+ tmpa = a->dp;
- /* alias for c->dp [dest] */
- tmpc = c->dp;
+ /* alias for c->dp [dest] */
+ tmpc = c->dp;
- /* zero carry */
- u = 0;
+ /* zero carry */
+ u = 0;
- /* compute columns */
- for (ix = 0; ix < a->used; ix++) {
- /* compute product and carry sum for this term */
- r = (mp_word)u + ((mp_word)*tmpa++ * (mp_word)b);
+ /* compute columns */
+ for (ix = 0; ix < a->used; ix++) {
+ /* compute product and carry sum for this term */
+ r = (mp_word)u + ((mp_word)*tmpa++ * (mp_word)b);
- /* mask off higher bits to get a single digit */
- *tmpc++ = (mp_digit) (r & ((mp_word) MP_MASK));
+ /* mask off higher bits to get a single digit */
+ *tmpc++ = (mp_digit)(r & (mp_word)MP_MASK);
- /* send carry into next iteration */
- u = (mp_digit) (r >> ((mp_word) DIGIT_BIT));
- }
+ /* send carry into next iteration */
+ u = (mp_digit)(r >> (mp_word)MP_DIGIT_BIT);
+ }
- /* store final carry [if any] and increment ix offset */
- *tmpc++ = u;
- ++ix;
+ /* store final carry [if any] and increment ix offset */
+ *tmpc++ = u;
+ ++ix;
- /* now zero digits above the top */
- while (ix++ < olduse) {
- *tmpc++ = 0;
- }
+ /* now zero digits above the top */
+ MP_ZERO_DIGITS(tmpc, olduse - ix);
- /* set used count */
- c->used = a->used + 1;
- mp_clamp(c);
+ /* set used count */
+ c->used = a->used + 1;
+ mp_clamp(c);
- return MP_OKAY;
+ return MP_OKAY;
}
#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */