denyhosts/clamscan/libclamav/tomsfastmath/mul/fp_mul_d.c
2022-10-22 18:41:00 +08:00

41 lines
908 B
C

/* TomsFastMath, a fast ISO C bignum library.
*
* This project is meant to fill in where LibTomMath
* falls short. That is speed ;-)
*
* This project is public domain and free for all purposes.
*
* Tom St Denis, tomstdenis@gmail.com
*/
#include "bignum_fast.h"
/* c = a * b */
void fp_mul_d(fp_int *a, fp_digit b, fp_int *c)
{
fp_word w;
int x, oldused;
oldused = c->used;
c->used = a->used;
c->sign = a->sign;
w = 0;
for (x = 0; x < a->used; x++) {
w = ((fp_word)a->dp[x]) * ((fp_word)b) + w;
c->dp[x] = (fp_digit)w;
w = w >> DIGIT_BIT;
}
if (w != 0 && (a->used != FP_SIZE)) {
c->dp[c->used++] = w;
++x;
}
for (; x < oldused; x++) {
c->dp[x] = 0;
}
fp_clamp(c);
}
/* $Source: /cvs/libtom/tomsfastmath/src/mul/fp_mul_d.c,v $ */
/* $Revision: 1.1 $ */
/* $Date: 2006/12/31 21:25:53 $ */