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#include <tommath.h>
#ifdef BN_MP_GET_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@iahu.ca, http://math.libtomcrypt.org
*/
/* get the lower 32-bits of an mp_int */
unsigned long mp_get_int(mp_int * a)
{
int i;
unsigned long res;
if (a->used == 0) {
return 0;
}
/* get number of digits of the lsb we have to read */
i = MIN(a->used,(int)((sizeof(unsigned long)*CHAR_BIT+DIGIT_BIT-1)/DIGIT_BIT))-1;
/* get most significant digit of result */
res = DIGIT(a,i);
while (--i >= 0) {
res = (res << DIGIT_BIT) | DIGIT(a,i);
}
/* force result to 32-bits always so it is consistent on non 32-bit platforms */
return res & 0xFFFFFFFFUL;
}
#endif
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