#include "tommath_private.h" #ifdef BN_MP_ADD_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ /* high level addition (handles signs) */ int mp_add(const mp_int *a, const mp_int *b, mp_int *c) { int sa, sb, res; /* get sign of both inputs */ sa = a->sign; sb = b->sign; /* handle two cases, not four */ if (sa == sb) { /* both positive or both negative */ /* add their magnitudes, copy the sign */ c->sign = sa; res = s_mp_add(a, b, c); } else { /* one positive, the other negative */ /* subtract the one with the greater magnitude from */ /* the one of the lesser magnitude. The result gets */ /* the sign of the one with the greater magnitude. */ if (mp_cmp_mag(a, b) == MP_LT) { c->sign = sb; res = s_mp_sub(b, a, c); } else { c->sign = sa; res = s_mp_sub(a, b, c); } } return res; } #endif