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authorSteffen Jaeckel <s@jaeckel.eu>2020-05-26 17:36:47 +0200
committerGitHub <noreply@github.com>2020-05-26 23:36:47 +0800
commitb4bd23b4d2a4c640880b49069e02cd598dd03416 (patch)
treefb480b4e501cc69b305de95fb15259aa6afa1963 /libtommath/bn_s_mp_prime_is_divisible.c
parent724e61f8ae9e9f216b0252e41c5ebd5d64ad79a6 (diff)
Update LibTomMath to 1.2.0 (#84)
* update C files * update other files * update headers * update makefiles * remove mp_set/get_double() * use ltm 1.2.0 API * update ltm_desc * use bundled tommath if system-tommath is too old * XMALLOC etc. were changed to MP_MALLOC etc.
Diffstat (limited to 'libtommath/bn_s_mp_prime_is_divisible.c')
-rw-r--r--libtommath/bn_s_mp_prime_is_divisible.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/libtommath/bn_s_mp_prime_is_divisible.c b/libtommath/bn_s_mp_prime_is_divisible.c
new file mode 100644
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--- /dev/null
+++ b/libtommath/bn_s_mp_prime_is_divisible.c
@@ -0,0 +1,35 @@
+#include "tommath_private.h"
+#ifdef BN_S_MP_PRIME_IS_DIVISIBLE_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+/* determines if an integers is divisible by one
+ * of the first PRIME_SIZE primes or not
+ *
+ * sets result to 0 if not, 1 if yes
+ */
+mp_err s_mp_prime_is_divisible(const mp_int *a, mp_bool *result)
+{
+ int ix;
+ mp_err err;
+ mp_digit res;
+
+ /* default to not */
+ *result = MP_NO;
+
+ for (ix = 0; ix < PRIVATE_MP_PRIME_TAB_SIZE; ix++) {
+ /* what is a mod LBL_prime_tab[ix] */
+ if ((err = mp_mod_d(a, s_mp_prime_tab[ix], &res)) != MP_OKAY) {
+ return err;
+ }
+
+ /* is the residue zero? */
+ if (res == 0u) {
+ *result = MP_YES;
+ return MP_OKAY;
+ }
+ }
+
+ return MP_OKAY;
+}
+#endif