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[xonotic/d0_blind_id.git] / d0_bignum-gmp.c

diff --git a/d0_bignum-gmp.c b/d0_bignum-gmp.c
index 45f46a2be7cf678a7de27743313c2ff18791858f..3b36b7da9ce384b9ed9f0f3afcd5da38260823fc 100644 (file)
--- a/d0_bignum-gmp.c
+++ b/d0_bignum-gmp.c
@@ -363,6 +363,13 @@ d0_bignum_t *d0_bignum_mod_add(d0_bignum_t *r, const d0_bignum_t *a, const d0_bi
        return r;
 }
 
+d0_bignum_t *d0_bignum_mod_sub(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b, const d0_bignum_t *m)
+{
+       r = d0_bignum_sub(r, a, b);
+       mpz_fdiv_r(r->z, r->z, m->z);
+       return r;
+}
+
 d0_bignum_t *d0_bignum_mod_mul(d0_bignum_t *r, const d0_bignum_t *a, const d0_bignum_t *b, const d0_bignum_t *m)
 {
        r = d0_bignum_mul(r, a, b);