Mercurial > dropbear
view libtommath/bn_mp_radix_size.c @ 1837:df7bfd2f7d45
Add "make test" target to run pytest
This will create a virtualenv if required.
There is a bit of churn here reverting to autoconf 2.59 in generated
config.h.in and configure
author | Matt Johnston <matt@codeconstruct.com.au> |
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date | Mon, 18 Oct 2021 14:24:32 +0800 |
parents | 1051e4eea25a |
children |
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#include "tommath_private.h" #ifdef BN_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, int *size) { mp_err err; int 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_IS_ZERO(a)) { *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 ((err = mp_init_copy(&t, a)) != MP_OKAY) { return err; } /* force temp to positive */ t.sign = MP_ZPOS; /* fetch out all of the digits */ while (!MP_IS_ZERO(&t)) { if ((err = mp_div_d(&t, (mp_digit)radix, &t, &d)) != MP_OKAY) { goto LBL_ERR; } ++digs; } /* return digs + 1, the 1 is for the NULL byte that would be required. */ *size = digs + 1; err = MP_OKAY; LBL_ERR: mp_clear(&t); return err; } #endif