libtommath/bn_mp_tc_div_2d.c
2019-02-02 07:39:23 +01:00

36 lines
905 B
C

#include "tommath_private.h"
#ifdef BN_MP_TC_DIV_2D_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
*/
/* two complement right shift */
int mp_tc_div_2d(const mp_int *a, int b, mp_int *c)
{
int res;
if (a->sign == MP_ZPOS) {
return mp_div_2d(a, b, c, NULL);
}
res = mp_add_d(a, 1uL, c);
if (res != MP_OKAY) {
return res;
}
res = mp_div_2d(c, b, c, NULL);
return (res == MP_OKAY) ? mp_sub_d(c, 1uL, c) : res;
}
#endif
/* ref: $Format:%D$ */
/* git commit: $Format:%H$ */
/* commit time: $Format:%ai$ */