/*
* Generate and munge a 64bit number.
*/
u64 rand64(void)
{
unsigned long r = 0;
if (rand_bool()) {
/* 32-bit ranges. */
r = rand32();
} else {
/* 33:64-bit ranges. */
switch (rand() % 7) {
case 0: r = rand_single_bit(64);
break;
case 1: r = randbits(64);
break;
case 2: r = rand32() | rand32() << 31;
break;
case 3: r = taviso();
break;
case 4: r = rand8x8();
break;
case 5: r = rept8(8);
break;
/* Sometimes pick a not-so-random number. */
case 6: return get_interesting_value();
}
/* limit the size */
switch (rand() % 4) {
case 0: r &= 0x000000ffffffffffULL;
break;
case 1: r &= 0x0000ffffffffffffULL;
break;
case 2: r &= 0x00ffffffffffffffULL;
break;
}
}
/* Sometimes invert the generated number. */
if (rand_bool())
r = ~r;
/* increase distribution in MSB */
if ((rand() % 10)) {
unsigned int i;
unsigned int rounds;
rounds = rand() % 4;
for (i = 0; i < rounds; i++)
r |= (1UL << ((__WORDSIZE - 1) - (rand() % 8)));
}
/* randomly flip sign bit. */
if (rand_bool())
r |= (1UL << (__WORDSIZE - 1));
return r;
}
/*
* Generate and munge a 64bit number.
*/
u64 rand64(void)
{
unsigned long r = 0;
if (RAND_BOOL()) {
/* 32-bit ranges. */
r = rand32();
} else {
/* 33:64-bit ranges. */
switch (rand() % 5) {
case 0: r = rand_single_bit(64);
break;
case 1: r = randbits(64);
break;
case 2: r = RAND_64();
break;
case 3: r = rept_byte();
break;
/* Sometimes pick a not-so-random number. */
case 4: return get_interesting_value();
}
/* limit the size */
switch (rand() % 4) {
case 0: r &= 0x000000ffffffffffULL;
break;
case 1: r &= 0x0000ffffffffffffULL;
break;
case 2: r &= 0x00ffffffffffffffULL;
break;
default: /* no limiting. */
break;
}
}
/* Sometimes invert the generated number. */
if (ONE_IN(25))
r = ~r;
/* increase distribution in MSB */
if (ONE_IN(10)) {
unsigned int i;
unsigned int rounds;
rounds = rand() % 4;
for (i = 0; i < rounds; i++)
r |= (1UL << ((__WORDSIZE - 1) - (rand() % 8)));
}
/* Sometimes flip sign */
if (ONE_IN(25))
r = ~r + 1;
return r;
}
/*
* Generate, and munge a 32bit number.
*/
unsigned int rand32(void)
{
unsigned long r = 0;
switch (rnd() % 7) {
case 0: r = RAND_BYTE();
break;
case 1: r = rand16();
break;
case 2: r = rand_single_bit(32);
break;
case 3: r = randbits(32);
break;
case 4: r = rnd();
break;
case 5: r = rept_byte();
break;
case 6: return get_interesting_value();
}
/* Sometimes deduct it from INT_MAX */
if (ONE_IN(25))
r = INT_MAX - r;
/* Sometimes flip sign */
if (ONE_IN(25))
r = ~r + 1;
/* we might get lucky if something is counting ints/longs etc. */
if (ONE_IN(4)) {
int _div = 1 << RAND_RANGE(1, 4); /* 2,4,8 or 16 */
r /= _div;
}
/* limit the size */
switch (rnd() % 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;
}
static void fabricate_onepage_struct(char *page)
{
unsigned int i;
void **ptr;
for (i = 0; i < page_size; ) {
ptr = (void*)&page[i];
switch (rand() % 4) {
case 0:
i += sizeof(unsigned int);
if (i > page_size)
return;
*(unsigned int *)ptr = get_interesting_32bit_value();
break;
case 1:
i += sizeof(unsigned long);
if (i > page_size)
return;
*(unsigned long *)ptr = get_interesting_value();
break;
case 2:
i += sizeof(void *);
if (i > page_size)
return;
*ptr = get_address();
break;
case 3:
i += sizeof(unsigned int);
if (i > page_size)
return;
*(unsigned int *)ptr = rand() % page_size;
break;
default:
BUG("unreachable!\n");
return;
}
}
}
