dropbear/libtommath/bn_s_mp_get_bit.c
Steffen Jaeckel b4bd23b4d2
Update LibTomMath to 1.2.0 (#84)
* update C files

* update other files

* update headers

* update makefiles

* remove mp_set/get_double()

* use ltm 1.2.0 API

* update ltm_desc

* use bundled tommath if system-tommath is too old

* XMALLOC etc. were changed to MP_MALLOC etc.
2020-05-26 23:36:47 +08:00

22 lines
521 B
C

#include "tommath_private.h"
#ifdef BN_S_MP_GET_BIT_C
/* LibTomMath, multiple-precision integer library -- Tom St Denis */
/* SPDX-License-Identifier: Unlicense */
/* Get bit at position b and return MP_YES if the bit is 1, MP_NO if it is 0 */
mp_bool s_mp_get_bit(const mp_int *a, unsigned int b)
{
mp_digit bit;
int limb = (int)(b / MP_DIGIT_BIT);
if (limb >= a->used) {
return MP_NO;
}
bit = (mp_digit)1 << (b % MP_DIGIT_BIT);
return ((a->dp[limb] & bit) != 0u) ? MP_YES : MP_NO;
}
#endif