Subversion Repositories planix.SVN

#include "os.h"
#include <mp.h>
#include "dat.h"

mpint*
mprand(int bits, void (*gen)(uchar*, int), mpint *b)
{
        mpdigit mask;

        if(b == nil){
                b = mpnew(bits);
                setmalloctag(b, getcallerpc(&bits));
        }else
                mpbits(b, bits);

        b->sign = 1;
        b->top = DIGITS(bits);
        (*gen)((uchar*)b->p, b->top*Dbytes);

        mask = ((mpdigit)1 << (bits%Dbits))-1;
        if(mask != 0)
                b->p[b->top-1] &= mask;

        return mpnorm(b);
}