1 #include <tommath.h> 2 #ifdef BN_MP_NEG_C 3 /* LibTomMath, multiple-precision integer library -- Tom St Denis 4 * 5 * LibTomMath is a library that provides multiple-precision 6 * integer arithmetic as well as number theoretic functionality. 7 * 8 * The library was designed directly after the MPI library by 9 * Michael Fromberger but has been written from scratch with 10 * additional optimizations in place. 11 * 12 * The library is free for all purposes without any express 13 * guarantee it works. 14 * 15 * Tom St Denis, tomstdenis (at) gmail.com, http://math.libtomcrypt.com 16 */ 17 18 /* b = -a */ 19 int mp_neg (mp_int * a, mp_int * b) 20 { 21 int res; 22 if (a != b) { 23 if ((res = mp_copy (a, b)) != MP_OKAY) { 24 return res; 25 } 26 } 27 28 if (mp_iszero(b) != MP_YES) { 29 b->sign = (a->sign == MP_ZPOS) ? MP_NEG : MP_ZPOS; 30 } else { 31 b->sign = MP_ZPOS; 32 } 33 34 return MP_OKAY; 35 } 36 #endif 37 38 /* $Source: /cvs/libtom/libtommath/bn_mp_neg.c,v $ */ 39 /* $Revision: 1.3 $ */ 40 /* $Date: 2006/03/31 14:18:44 $ */ 41
