/*
* Generate, and munge a 32bit number.
*/
unsigned int rand32(void)
{
unsigned long r = 0;
r = __rand32();
if (rand_bool()) {
unsigned int i;
unsigned int rounds;
/* mangle it. */
rounds = rand() % 3;
for (i = 0; i < rounds; i++) {
if (rand_bool())
r |= __rand32();
else
r ^= __rand32();
}
}
/* Sometimes deduct it from INT_MAX */
if (rand_bool())
r = INT_MAX - r;
/* Sometimes flip sign */
if (rand_bool())
r |= (1L << 31);
/* we might get lucky if something is counting ints/longs etc. */
if (rand() % 100 < 25) {
int _div = 1 << rand_range(1, 4); /* 2,4,8 or 16 */
r /= _div;
}
/* limit the size */
switch (rand() % 5) {
case 0: r &= 0xff;
break;
case 1: r &= 0xffff;
break;
case 2: r &= PAGE_MASK;
break;
case 3: r &= 0xffffff;
break;
case 4: // do nothing
break;
}
return r;
}
unsigned int rand32(void)
{
unsigned long r = 0;
r = __rand32();
if (rand_bool()) {
unsigned int i;
unsigned int rounds;
/* mangle it. */
rounds = rand() % 3;
for (i = 0; i < rounds; i++) {
switch (rand_bool()) {
case 0: r |= __rand32();
break;
case 1: r ^= __rand32();
break;
default:
break;
}
}
}
if (rand_bool())
r = INT_MAX - r;
if (rand_bool())
r |= (1L << 31);
/* limit the size */
switch (rand() % 4) {
case 0: r &= 0xff;
break;
case 1: r &= 0xffff;
break;
case 2: r &= 0xffffff;
break;
default:
break;
}
return r;
}
static void __init_rand32(struct taus88_state *state, unsigned int seed)
{
int cranks = 6;
#define LCG(x, seed) ((x) * 69069 ^ (seed))
state->s1 = __seed(LCG((2^31) + (2^17) + (2^7), seed), 1);
state->s2 = __seed(LCG(state->s1, seed), 7);
state->s3 = __seed(LCG(state->s2, seed), 15);
while (cranks--)
__rand32(state);
}
