view libtommath/bn_mp_signed_rsh.c @ 1811:7dc92355a986

Remove some obselete autoconf bits. Keeps autoconf 2.71 happy, though we leave the prereq version at 2.59
author Matt Johnston <matt@ucc.asn.au>
date Tue, 30 Mar 2021 20:42:04 +0800
parents 1051e4eea25a
children
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line source
#include "tommath_private.h"
#ifdef BN_MP_SIGNED_RSH_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */

/* shift right by a certain bit count with sign extension */
mp_err mp_signed_rsh(const mp_int *a, int b, mp_int *c)
{
   mp_err 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