Mercurial > dropbear
view libtommath/bn_mp_toradix_n.c @ 1613:caa9bb54dfa0
fix #endif (#59)
author | François Perrad <francois.perrad@gadz.org> |
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date | Wed, 28 Feb 2018 15:10:14 +0100 |
parents | 8bba51a55704 |
children | f52919ffd3b1 |
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#include <tommath_private.h> #ifdef BN_MP_TORADIX_N_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. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, [email protected], http://libtom.org */ /* stores a bignum as a ASCII string in a given radix (2..64) * * Stores upto maxlen-1 chars and always a NULL byte */ int mp_toradix_n(mp_int * a, char *str, int radix, int maxlen) { int res, digs; mp_int t; mp_digit d; char *_s = str; /* check range of the maxlen, radix */ if ((maxlen < 2) || (radix < 2) || (radix > 64)) { return MP_VAL; } /* quick out if its zero */ if (mp_iszero(a) == MP_YES) { *str++ = '0'; *str = '\0'; return MP_OKAY; } if ((res = mp_init_copy (&t, a)) != MP_OKAY) { return res; } /* if it is negative output a - */ if (t.sign == MP_NEG) { /* we have to reverse our digits later... but not the - sign!! */ ++_s; /* store the flag and mark the number as positive */ *str++ = '-'; t.sign = MP_ZPOS; /* subtract a char */ --maxlen; } digs = 0; while (mp_iszero (&t) == MP_NO) { if (--maxlen < 1) { /* no more room */ break; } if ((res = mp_div_d (&t, (mp_digit) radix, &t, &d)) != MP_OKAY) { mp_clear (&t); return res; } *str++ = mp_s_rmap[d]; ++digs; } /* reverse the digits of the string. In this case _s points * to the first digit [exluding the sign] of the number */ bn_reverse ((unsigned char *)_s, digs); /* append a NULL so the string is properly terminated */ *str = '\0'; mp_clear (&t); return MP_OKAY; } #endif /* ref: $Format:%D$ */ /* git commit: $Format:%H$ */ /* commit time: $Format:%ai$ */