|
142
|
1 #include <tommath.h> |
|
|
2 #ifdef BN_MP_COPY_C |
|
2
|
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, [email protected], http://math.libtomcrypt.org |
|
|
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 } |
|
142
|
64 #endif |
