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#include "tommath_private.h"
#ifdef BN_MP_RADIX_SIZE_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
*/
/* returns size of ASCII reprensentation */
int mp_radix_size(const mp_int *a, int radix, int *size)
{
int res, digs;
mp_int t;
mp_digit d;
*size = 0;
/* make sure the radix is in range */
if ((radix < 2) || (radix > 64)) {
return MP_VAL;
}
if (mp_iszero(a) == MP_YES) {
*size = 2;
return MP_OKAY;
}
/* special case for binary */
if (radix == 2) {
*size = mp_count_bits(a) + ((a->sign == MP_NEG) ? 1 : 0) + 1;
return MP_OKAY;
}
/* digs is the digit count */
digs = 0;
/* if it's negative add one for the sign */
if (a->sign == MP_NEG) {
++digs;
}
/* init a copy of the input */
if ((res = mp_init_copy(&t, a)) != MP_OKAY) {
return res;
}
/* force temp to positive */
t.sign = MP_ZPOS;
/* fetch out all of the digits */
while (mp_iszero(&t) == MP_NO) {
if ((res = mp_div_d(&t, (mp_digit)radix, &t, &d)) != MP_OKAY) {
mp_clear(&t);
return res;
}
++digs;
}
mp_clear(&t);
/* return digs + 1, the 1 is for the NULL byte that would be required. */
*size = digs + 1;
return MP_OKAY;
}
#endif
/* ref: HEAD -> master, tag: v1.1.0 */
/* git commit: 08549ad6bc8b0cede0b357a9c341c5c6473a9c55 */
/* commit time: 2019-01-28 20:32:32 +0100 */
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