struct hash *hash_new(unsigned int n_buckets,
void (*free_value)(void *value))
{
struct hash *hash;
n_buckets = ALIGN_POWER2(n_buckets);
hash = calloc(1, sizeof(struct hash) +
n_buckets * sizeof(struct hash_bucket));
if (hash == NULL)
return NULL;
hash->n_buckets = n_buckets;
hash->free_value = free_value;
hash->step = n_buckets / 32;
if (hash->step == 0)
hash->step = 4;
else if (hash->step > 64)
hash->step = 64;
return hash;
}
static void test_align_power2(void) {
unsigned long i, p2;
log_info("/* %s */", __func__);
assert_se(ALIGN_POWER2(0) == 0);
assert_se(ALIGN_POWER2(1) == 1);
assert_se(ALIGN_POWER2(2) == 2);
assert_se(ALIGN_POWER2(3) == 4);
assert_se(ALIGN_POWER2(12) == 16);
assert_se(ALIGN_POWER2(ULONG_MAX) == 0);
assert_se(ALIGN_POWER2(ULONG_MAX - 1) == 0);
assert_se(ALIGN_POWER2(ULONG_MAX - 1024) == 0);
assert_se(ALIGN_POWER2(ULONG_MAX / 2) == ULONG_MAX / 2 + 1);
assert_se(ALIGN_POWER2(ULONG_MAX + 1) == 0);
for (i = 1; i < 131071; ++i) {
for (p2 = 1; p2 < i; p2 <<= 1)
/* empty */ ;
assert_se(ALIGN_POWER2(i) == p2);
}
for (i = ULONG_MAX - 1024; i < ULONG_MAX; ++i) {
for (p2 = 1; p2 && p2 < i; p2 <<= 1)
/* empty */ ;
assert_se(ALIGN_POWER2(i) == p2);
}
}
