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#include "tommath_private.h"
#ifdef BN_MP_GET_LONG_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.
*/
/* get the lower unsigned long of an mp_int, platform dependent */
unsigned long mp_get_long(const 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);
#if (ULONG_MAX != 0xffffffffuL) || (DIGIT_BIT < 32)
while (--i >= 0) {
res = (res << DIGIT_BIT) | DIGIT(a, i);
}
#endif
return res;
}
#endif
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