kc3-lang/libtommath/mp_radix_size.c

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• Hash : 1cc289d2
  Author :
  Date : 2019-11-09T20:23:03
  

  better use of mp_isneg() and mp_iszero()

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• mp_radix_size.c

• #include "tommath_private.h"
  #ifdef MP_RADIX_SIZE_C
  /* LibTomMath, multiple-precision integer library -- Tom St Denis */
  /* SPDX-License-Identifier: Unlicense */
  
  /* returns size of ASCII representation */
  mp_err mp_radix_size(const mp_int *a, int radix, size_t *size)
  {
     mp_err err;
     mp_int a_;
     uint32_t b;
  
     /* make sure the radix is in range */
     if ((radix < 2) || (radix > 64)) {
        return MP_VAL;
     }
  
     if (mp_iszero(a)) {
        *size = 2;
        return MP_OKAY;
     }
  
     a_ = *a;
     a_.sign = MP_ZPOS;
     if ((err = mp_log_u32(&a_, (uint32_t)radix, &b)) != MP_OKAY) {
        goto LBL_ERR;
     }
  
     /* mp_ilogb truncates to zero, hence we need one extra put on top and one for `\0`. */
     *size = (size_t)b + 2U + (mp_isneg(a) ? 1U : 0U);
  
  LBL_ERR:
     return err;
  }
  #endif
  

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