1 #include <tommath.h> 2 #ifdef BN_MP_COPY_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 /* copy, b = a */ 19 int 20 mp_copy (mp_int * a, mp_int * b) 21 { 22 int res, n; 23 24 /* if dst == src do nothing */ 25 if (a == b) { 26 return MP_OKAY; 27 } 28 29 /* grow dest */ 30 if (b->alloc < a->used) { 31 if ((res = mp_grow (b, a->used)) != MP_OKAY) { 32 return res; 33 } 34 } 35 36 /* zero b and copy the parameters over */ 37 { 38 register mp_digit *tmpa, *tmpb; 39 40 /* pointer aliases */ 41 42 /* source */ 43 tmpa = a->dp; 44 45 /* destination */ 46 tmpb = b->dp; 47 48 /* copy all the digits */ 49 for (n = 0; n < a->used; n++) { 50 *tmpb++ = *tmpa++; 51 } 52 53 /* clear high digits */ 54 for (; n < b->used; n++) { 55 *tmpb++ = 0; 56 } 57 } 58 59 /* copy used count and sign */ 60 b->used = a->used; 61 b->sign = a->sign; 62 return MP_OKAY; 63 } 64 #endif 65 66 /* $Source: /cvs/libtom/libtommath/bn_mp_copy.c,v $ */ 67 /* $Revision: 1.3 $ */ 68 /* $Date: 2006/03/31 14:18:44 $ */ 69
