kc3-lang/libtommath/bn_mp_mod.c

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• Hash : 4534056c
  Author :
  Date : 2019-05-13T00:22:18
  

  use enums mp_err, mp_ord, mp_bool, mp_sign * MP_USE_ENUMS enables enums * Wc++-compat catches some implicit conversions if MP_USE_ENUMS is defined * 100% backwards compatible API/ABI if MP_USE_ENUMS is not defined

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• bn_mp_mod.c

• #include "tommath_private.h"
  #ifdef BN_MP_MOD_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* c = a mod b, 0 <= c < b if b > 0, b < c <= 0 if b < 0 */
  mp_err mp_mod(const mp_int *a, const mp_int *b, mp_int *c)
  {
     mp_int  t;
     mp_err  res;
  
     if ((res = mp_init_size(&t, b->used)) != MP_OKAY) {
        return res;
     }
  
     if ((res = mp_div(a, b, NULL, &t)) != MP_OKAY) {
        mp_clear(&t);
        return res;
     }
  
     if (MP_IS_ZERO(&t) || (t.sign == b->sign)) {
        res = MP_OKAY;
        mp_exch(&t, c);
     } else {
        res = mp_add(b, &t, c);
     }
  
     mp_clear(&t);
     return res;
  }
  #endif
  

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