1 /*	$NetBSD: bn_mp_set_int.c,v 1.1.1.1 2011/04/13 18:14:54 elric Exp $	*/
2 
3 #include <tommath.h>
4 #ifdef BN_MP_SET_INT_C
5 /* LibTomMath, multiple-precision integer library -- Tom St Denis
6  *
7  * LibTomMath is a library that provides multiple-precision
8  * integer arithmetic as well as number theoretic functionality.
9  *
10  * The library was designed directly after the MPI library by
11  * Michael Fromberger but has been written from scratch with
12  * additional optimizations in place.
13  *
14  * The library is free for all purposes without any express
15  * guarantee it works.
16  *
17  * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
18  */
19 
20 /* set a 32-bit const */
21 int mp_set_int (mp_int * a, unsigned long b)
22 {
23   int     x, res;
24 
25   mp_zero (a);
26 
27   /* set four bits at a time */
28   for (x = 0; x < 8; x++) {
29     /* shift the number up four bits */
30     if ((res = mp_mul_2d (a, 4, a)) != MP_OKAY) {
31       return res;
32     }
33 
34     /* OR in the top four bits of the source */
35     a->dp[0] |= (b >> 28) & 15;
36 
37     /* shift the source up to the next four bits */
38     b <<= 4;
39 
40     /* ensure that digits are not clamped off */
41     a->used += 1;
42   }
43   mp_clamp (a);
44   return MP_OKAY;
45 }
46 #endif
47 
48 /* Source: /cvs/libtom/libtommath/bn_mp_set_int.c,v */
49 /* Revision: 1.4 */
50 /* Date: 2006/12/28 01:25:13 */
51