#define _XOPEN_SOURCE 700

#include <stdio.h>

#include <stdlib.h>

#include "test.h"

/* naive statistical checks */

/* error p ~ 1.6e-6 */

static int chkmissing(long *x)

{

	int d[8] = {0};

	int i;

	for (i = 0; i < 100; i++)

		d[x[i]%8]++;

	for (i = 0; i < 8; i++)

		if (d[i]==0)

			return 1;

	return 0;

}

/* error p ~ 4e-6 */

static int chkrepeat(long *x)

{

	int i, j;

	for (i = 0; i < 100; i++)

		for (j = 0; j < i; j++)

			if (x[i] == x[j])

				return 1;

	return 0;

}

/* error p ~ 1e-6 */

static unsigned orx;

static int chkones(long *x)

{

	int i;

	orx = 0;

	for (i = 0; i < 20; i++)

		orx |= x[i];

	return orx != 0x7fffffff;

}

void checkseed(unsigned seed, long *x)

{

	int i;

	srandom(seed);

	for (i = 0; i < 100; i++)

		x[i] = random();

	if (chkmissing(x))

		t_error("weak seed %d, missing pattern in low bits\n", seed);

	if (chkrepeat(x))

		t_error("weak seed %d, exact repeats\n", seed);

	if (chkones(x))

		t_error("weak seed %d, or pattern: 0x%08x\n", seed, orx);

}

int main()

{

	long x[100];

	long y,z;

	int i;

	char state[128];

	char *p;

	char *q;

	for (i = 0; i < 100; i++)

		x[i] = random();

	p = initstate(1, state, sizeof state);

	for (i = 0; i < 100; i++)

		if (x[i] != (y = random()))

			t_error("initstate(1) is not default: (%d) default: %ld, seed1: %ld\n", i, x[i], y);

	for (i = 0; i < 10; i++) {

		z = random();

		q = setstate(p);

		if (z != (y = random()))

			t_error("setstate failed (%d) orig: %ld, reset: %ld\n", i, z, y);

		p = setstate(q);

	}

	srandom(1);

	for (i = 0; i < 100; i++)

		if (x[i] != (y = random()))

			t_error("srandom(1) is not default: (%d) default: %ld, seed1: %ld\n", i, x[i], y);

	checkseed(0x7fffffff, x);

	for (i = 0; i < 10; i++)

		checkseed(i, x);

	return t_status;

}