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-rw-r--r--libtommath/bn_mp_gcd.c54
1 files changed, 21 insertions, 33 deletions
diff --git a/libtommath/bn_mp_gcd.c b/libtommath/bn_mp_gcd.c
index 05030c2..53029ba 100644
--- a/libtommath/bn_mp_gcd.c
+++ b/libtommath/bn_mp_gcd.c
@@ -1,37 +1,29 @@
#include "tommath_private.h"
#ifdef BN_MP_GCD_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.
- *
- * SPDX-License-Identifier: Unlicense
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
/* Greatest Common Divisor using the binary method */
-int mp_gcd(const mp_int *a, const mp_int *b, mp_int *c)
+mp_err mp_gcd(const mp_int *a, const mp_int *b, mp_int *c)
{
mp_int u, v;
- int k, u_lsb, v_lsb, res;
+ int k, u_lsb, v_lsb;
+ mp_err err;
/* either zero than gcd is the largest */
- if (mp_iszero(a) == MP_YES) {
+ if (MP_IS_ZERO(a)) {
return mp_abs(b, c);
}
- if (mp_iszero(b) == MP_YES) {
+ if (MP_IS_ZERO(b)) {
return mp_abs(a, c);
}
/* get copies of a and b we can modify */
- if ((res = mp_init_copy(&u, a)) != MP_OKAY) {
- return res;
+ if ((err = mp_init_copy(&u, a)) != MP_OKAY) {
+ return err;
}
- if ((res = mp_init_copy(&v, b)) != MP_OKAY) {
+ if ((err = mp_init_copy(&v, b)) != MP_OKAY) {
goto LBL_U;
}
@@ -41,33 +33,33 @@ int mp_gcd(const mp_int *a, const mp_int *b, mp_int *c)
/* B1. Find the common power of two for u and v */
u_lsb = mp_cnt_lsb(&u);
v_lsb = mp_cnt_lsb(&v);
- k = MIN(u_lsb, v_lsb);
+ k = MP_MIN(u_lsb, v_lsb);
if (k > 0) {
/* divide the power of two out */
- if ((res = mp_div_2d(&u, k, &u, NULL)) != MP_OKAY) {
+ if ((err = mp_div_2d(&u, k, &u, NULL)) != MP_OKAY) {
goto LBL_V;
}
- if ((res = mp_div_2d(&v, k, &v, NULL)) != MP_OKAY) {
+ if ((err = mp_div_2d(&v, k, &v, NULL)) != MP_OKAY) {
goto LBL_V;
}
}
/* divide any remaining factors of two out */
if (u_lsb != k) {
- if ((res = mp_div_2d(&u, u_lsb - k, &u, NULL)) != MP_OKAY) {
+ if ((err = mp_div_2d(&u, u_lsb - k, &u, NULL)) != MP_OKAY) {
goto LBL_V;
}
}
if (v_lsb != k) {
- if ((res = mp_div_2d(&v, v_lsb - k, &v, NULL)) != MP_OKAY) {
+ if ((err = mp_div_2d(&v, v_lsb - k, &v, NULL)) != MP_OKAY) {
goto LBL_V;
}
}
- while (mp_iszero(&v) == MP_NO) {
+ while (!MP_IS_ZERO(&v)) {
/* make sure v is the largest */
if (mp_cmp_mag(&u, &v) == MP_GT) {
/* swap u and v to make sure v is >= u */
@@ -75,30 +67,26 @@ int mp_gcd(const mp_int *a, const mp_int *b, mp_int *c)
}
/* subtract smallest from largest */
- if ((res = s_mp_sub(&v, &u, &v)) != MP_OKAY) {
+ if ((err = s_mp_sub(&v, &u, &v)) != MP_OKAY) {
goto LBL_V;
}
/* Divide out all factors of two */
- if ((res = mp_div_2d(&v, mp_cnt_lsb(&v), &v, NULL)) != MP_OKAY) {
+ if ((err = mp_div_2d(&v, mp_cnt_lsb(&v), &v, NULL)) != MP_OKAY) {
goto LBL_V;
}
}
/* multiply by 2**k which we divided out at the beginning */
- if ((res = mp_mul_2d(&u, k, c)) != MP_OKAY) {
+ if ((err = mp_mul_2d(&u, k, c)) != MP_OKAY) {
goto LBL_V;
}
c->sign = MP_ZPOS;
- res = MP_OKAY;
+ err = MP_OKAY;
LBL_V:
mp_clear(&u);
LBL_U:
mp_clear(&v);
- return res;
+ return err;
}
#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */