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#include <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"
#include "longlong.h"
#include "mpfr.h"
/* Computes a random mpfr in [0, 1[ with precision PREC */
extern long random _PROTO((void));
extern int srandom _PROTO((unsigned int));
void
#if __STDC__
mpfr_random(mpfr_ptr x)
#else
mpfr_random(x)
mpfr_ptr x;
#endif
{
mp_limb_t *xp; unsigned long xs, i, cnt;
xp = MANT(x);
xs = ABSSIZE(x);
for (i = 0; i < xs; i++)
{
/* random() c/sh/ould be replaced by a homemade random number generator.
Indeed, if on Linux random is a good RNG, this is definitely not
the case in most Un*xes. */
xp[i] = random();
}
count_leading_zeros(cnt, xp[xs - 1]);
if (cnt) mpn_lshift(xp, xp, xs, cnt);
EXP(x) = -cnt;
mpfr_round_raw(xp, xp, PREC(x), (SIGN(x)<0), PREC(x), random()&3);
/* ignore any possible carry (this is sheer laziness). */
}
void
mpfr_srandom(unsigned long seed)
{
srandom(seed);
}
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