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#include <tommath.h>
#ifdef BN_MP_SET_INT_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, tomstdenis@gmail.com, http://math.libtomcrypt.com
*/
/* set a 32-bit const */
int mp_set_int (mp_int * a, unsigned long b)
{
int x, res;
mp_zero (a);
/* set four bits at a time */
for (x = 0; x < 8; x++) {
/* shift the number up four bits */
if ((res = mp_mul_2d (a, 4, a)) != MP_OKAY) {
return res;
}
/* OR in the top four bits of the source */
a->dp[0] |= (b >> 28) & 15;
/* shift the source up to the next four bits */
b <<= 4;
/* ensure that digits are not clamped off */
a->used += 1;
}
mp_clamp (a);
return MP_OKAY;
}
#endif
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